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kernel/0001-apply-preempt-RT-patch.patch

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From 9ab4249a2de8f19956276e268b56739e2fdc68f9 Mon Sep 17 00:00:00 2001
From: zhangyu <zhangyu4@kylinos.cn>
Date: Tue, 19 Nov 2024 12:08:53 +0800
Subject: [PATCH 1/2] 20241119-rt1
---
.../Expedited-Grace-Periods.rst | 4 +-
.../RCU/Design/Requirements/Requirements.rst | 26 +-
Documentation/RCU/checklist.rst | 2 +-
Documentation/RCU/rcubarrier.rst | 6 +-
Documentation/RCU/stallwarn.rst | 4 +-
Documentation/RCU/whatisRCU.rst | 10 +-
.../admin-guide/kernel-parameters.txt | 11 +
Documentation/driver-api/io-mapping.rst | 92 +-
arch/Kconfig | 8 +-
arch/alpha/include/asm/kmap_types.h | 15 -
arch/alpha/include/asm/spinlock_types.h | 4 -
arch/arc/Kconfig | 1 +
arch/arc/include/asm/highmem.h | 26 +-
arch/arc/include/asm/kmap_types.h | 14 -
arch/arc/mm/highmem.c | 54 +-
arch/arm/Kconfig | 6 +-
arch/arm/include/asm/fixmap.h | 4 +-
arch/arm/include/asm/hardirq.h | 11 +-
arch/arm/include/asm/highmem.h | 34 +-
arch/arm/include/asm/irq.h | 2 +
arch/arm/include/asm/kmap_types.h | 10 -
arch/arm/include/asm/spinlock_types.h | 4 -
arch/arm/include/asm/thread_info.h | 5 +-
arch/arm/kernel/asm-offsets.c | 1 +
arch/arm/kernel/entry-armv.S | 19 +-
arch/arm/kernel/signal.c | 3 +-
arch/arm/kernel/smp.c | 2 -
arch/arm/mm/Makefile | 1 -
arch/arm/mm/cache-feroceon-l2.c | 6 +-
arch/arm/mm/cache-xsc3l2.c | 4 +-
arch/arm/mm/fault.c | 3 +
arch/arm/mm/highmem.c | 121 --
arch/arm64/Kconfig | 3 +
arch/arm64/include/asm/hardirq.h | 7 +-
arch/arm64/include/asm/preempt.h | 28 +-
arch/arm64/include/asm/spinlock_types.h | 4 -
arch/arm64/include/asm/thread_info.h | 8 +-
arch/arm64/kernel/asm-offsets.c | 1 +
arch/arm64/kernel/entry.S | 13 +-
arch/arm64/kernel/fpsimd.c | 13 +-
arch/arm64/kernel/ipi_nmi.c | 2 -
arch/arm64/kernel/signal.c | 2 +-
arch/arm64/kvm/arm.c | 6 +-
arch/csky/Kconfig | 1 +
arch/csky/include/asm/fixmap.h | 4 +-
arch/csky/include/asm/highmem.h | 6 +-
arch/csky/mm/highmem.c | 75 +-
arch/hexagon/include/asm/spinlock_types.h | 4 -
arch/ia64/include/asm/kmap_types.h | 13 -
arch/ia64/include/asm/spinlock_types.h | 4 -
arch/ia64/kernel/time.c | 20 +-
arch/microblaze/Kconfig | 1 +
arch/microblaze/include/asm/fixmap.h | 4 +-
arch/microblaze/include/asm/highmem.h | 6 +-
arch/microblaze/mm/Makefile | 1 -
arch/microblaze/mm/highmem.c | 78 -
arch/microblaze/mm/init.c | 6 -
arch/mips/Kconfig | 1 +
arch/mips/include/asm/fixmap.h | 4 +-
arch/mips/include/asm/highmem.h | 6 +-
arch/mips/include/asm/kmap_types.h | 13 -
arch/mips/kernel/crash_dump.c | 42 +-
arch/mips/mm/highmem.c | 77 -
arch/mips/mm/init.c | 4 -
arch/nds32/Kconfig.cpu | 1 +
arch/nds32/include/asm/fixmap.h | 4 +-
arch/nds32/include/asm/highmem.h | 22 +-
arch/nds32/mm/Makefile | 1 -
arch/nds32/mm/highmem.c | 48 -
arch/openrisc/mm/init.c | 1 -
arch/openrisc/mm/ioremap.c | 1 -
arch/parisc/include/asm/hardirq.h | 1 -
arch/parisc/include/asm/kmap_types.h | 13 -
arch/powerpc/Kconfig | 4 +
arch/powerpc/include/asm/cmpxchg.h | 2 +-
arch/powerpc/include/asm/fixmap.h | 4 +-
arch/powerpc/include/asm/highmem.h | 7 +-
arch/powerpc/include/asm/kmap_types.h | 13 -
.../include/asm/simple_spinlock_types.h | 2 +-
arch/powerpc/include/asm/spinlock_types.h | 4 -
arch/powerpc/include/asm/stackprotector.h | 4 +
arch/powerpc/include/asm/thread_info.h | 17 +-
arch/powerpc/kernel/asm-offsets.c | 1 +
arch/powerpc/kernel/entry_32.S | 23 +-
arch/powerpc/kernel/exceptions-64e.S | 16 +-
arch/powerpc/kernel/irq.c | 2 +
arch/powerpc/kernel/misc_32.S | 2 +
arch/powerpc/kernel/misc_64.S | 2 +
arch/powerpc/kernel/nvram_64.c | 12 +-
arch/powerpc/kernel/syscall_64.c | 10 +-
arch/powerpc/kernel/time.c | 56 +-
arch/powerpc/kernel/traps.c | 8 +-
arch/powerpc/kernel/watchdog.c | 5 -
arch/powerpc/kexec/crash.c | 3 -
arch/powerpc/kvm/Kconfig | 1 +
arch/powerpc/mm/Makefile | 1 -
arch/powerpc/mm/highmem.c | 67 -
arch/powerpc/mm/mem.c | 7 -
arch/powerpc/platforms/powernv/opal-kmsg.c | 3 +-
arch/powerpc/platforms/pseries/iommu.c | 31 +-
arch/powerpc/xmon/xmon.c | 6 +-
arch/s390/Kconfig | 1 +
arch/s390/include/asm/spinlock_types.h | 4 -
arch/s390/include/asm/vtime.h | 1 -
arch/s390/kernel/vtime.c | 51 +-
arch/sh/include/asm/fixmap.h | 8 -
arch/sh/include/asm/hardirq.h | 14 +-
arch/sh/include/asm/kmap_types.h | 15 -
arch/sh/include/asm/spinlock_types.h | 4 -
arch/sh/kernel/irq.c | 4 +-
arch/sh/kernel/traps.c | 2 +-
arch/sh/mm/init.c | 8 -
arch/sparc/Kconfig | 1 +
arch/sparc/include/asm/highmem.h | 8 +-
arch/sparc/include/asm/kmap_types.h | 11 -
arch/sparc/include/asm/vaddrs.h | 4 +-
arch/sparc/kernel/irq_64.c | 2 +
arch/sparc/mm/Makefile | 3 -
arch/sparc/mm/highmem.c | 115 --
arch/sparc/mm/srmmu.c | 2 -
arch/um/include/asm/fixmap.h | 1 -
arch/um/include/asm/hardirq.h | 17 +-
arch/um/include/asm/kmap_types.h | 13 -
arch/um/kernel/kmsg_dump.c | 13 +-
arch/x86/Kconfig | 3 +
arch/x86/crypto/aesni-intel_glue.c | 22 +-
arch/x86/crypto/cast5_avx_glue.c | 21 +-
arch/x86/crypto/glue_helper.c | 26 +-
arch/x86/include/asm/fixmap.h | 5 +-
arch/x86/include/asm/fpu/api.h | 24 +-
arch/x86/include/asm/highmem.h | 13 +-
arch/x86/include/asm/iomap.h | 13 +-
arch/x86/include/asm/kmap_types.h | 13 -
arch/x86/include/asm/paravirt_types.h | 1 -
arch/x86/include/asm/preempt.h | 37 +-
arch/x86/include/asm/signal.h | 13 +
arch/x86/include/asm/stackprotector.h | 8 +-
arch/x86/include/asm/thread_info.h | 11 +
arch/x86/kernel/crash_dump_32.c | 48 +-
arch/x86/kernel/fpu/core.c | 12 +
arch/x86/kernel/irq_32.c | 2 +
arch/x86/kernel/irq_64.c | 2 +
arch/x86/kvm/x86.c | 8 +
arch/x86/mm/highmem_32.c | 59 -
arch/x86/mm/init_32.c | 15 -
arch/x86/mm/iomap_32.c | 57 +-
arch/xtensa/Kconfig | 1 +
arch/xtensa/include/asm/fixmap.h | 4 +-
arch/xtensa/include/asm/highmem.h | 12 +-
arch/xtensa/include/asm/spinlock_types.h | 4 -
arch/xtensa/mm/highmem.c | 46 +-
block/blk-mq.c | 124 +-
crypto/cryptd.c | 15 +-
drivers/atm/eni.c | 2 +-
drivers/block/zram/zram_drv.c | 36 +
drivers/block/zram/zram_drv.h | 1 +
drivers/char/tpm/tpm-dev-common.c | 1 -
drivers/char/tpm/tpm_tis.c | 29 +-
drivers/firewire/ohci.c | 4 +-
drivers/firmware/efi/efi.c | 5 +-
drivers/gpu/drm/i915/display/intel_sprite.c | 15 +-
.../gpu/drm/i915/gem/i915_gem_execbuffer.c | 7 +-
drivers/gpu/drm/i915/gt/intel_breadcrumbs.c | 5 +-
drivers/gpu/drm/i915/gt/intel_engine_pm.c | 8 +-
drivers/gpu/drm/i915/i915_gem.c | 40 +-
drivers/gpu/drm/i915/i915_irq.c | 2 +
drivers/gpu/drm/i915/i915_trace.h | 6 +-
drivers/gpu/drm/i915/selftests/i915_gem.c | 4 +-
drivers/gpu/drm/i915/selftests/i915_gem_gtt.c | 8 +-
.../drm/nouveau/nvkm/subdev/devinit/fbmem.h | 8 +-
drivers/gpu/drm/qxl/qxl_image.c | 18 +-
drivers/gpu/drm/qxl/qxl_ioctl.c | 27 +-
drivers/gpu/drm/qxl/qxl_object.c | 12 +-
drivers/gpu/drm/qxl/qxl_object.h | 4 +-
drivers/gpu/drm/qxl/qxl_release.c | 4 +-
drivers/gpu/drm/radeon/radeon_display.c | 2 +
drivers/gpu/drm/ttm/ttm_bo_util.c | 20 +-
drivers/gpu/drm/vmwgfx/vmwgfx_blit.c | 30 +-
drivers/hv/hyperv_vmbus.h | 1 +
drivers/hv/vmbus_drv.c | 8 +-
drivers/irqchip/irq-gic-v4.c | 2 +-
drivers/leds/trigger/Kconfig | 1 +
drivers/md/raid5.c | 7 +-
drivers/md/raid5.h | 1 +
drivers/mtd/mtdoops.c | 5 +-
drivers/net/ethernet/chelsio/cxgb/common.h | 6 +-
drivers/net/ethernet/chelsio/cxgb/cxgb2.c | 54 +-
drivers/net/ethernet/chelsio/cxgb/sge.c | 53 +-
drivers/net/ethernet/chelsio/cxgb/sge.h | 3 +-
drivers/net/ethernet/chelsio/cxgb/subr.c | 64 +-
drivers/net/ethernet/dlink/sundance.c | 2 +-
drivers/net/ethernet/jme.c | 10 +-
drivers/net/ethernet/jme.h | 2 +-
drivers/net/wireless/ath/ath9k/beacon.c | 2 +-
drivers/pci/controller/pci-hyperv.c | 2 +-
drivers/scsi/fcoe/fcoe.c | 16 +-
drivers/scsi/fcoe/fcoe_ctlr.c | 4 +-
drivers/scsi/libfc/fc_exch.c | 4 +-
drivers/tty/serial/8250/8250.h | 47 +-
drivers/tty/serial/8250/8250_core.c | 17 +-
drivers/tty/serial/8250/8250_fsl.c | 9 +
drivers/tty/serial/8250/8250_ingenic.c | 7 +
drivers/tty/serial/8250/8250_mtk.c | 29 +-
drivers/tty/serial/8250/8250_port.c | 92 +-
drivers/tty/serial/amba-pl011.c | 17 +-
drivers/tty/serial/omap-serial.c | 12 +-
drivers/tty/tty_buffer.c | 4 +-
fs/afs/dir_silly.c | 2 +-
fs/aio.c | 3 +-
fs/btrfs/ctree.h | 1 -
fs/cifs/readdir.c | 2 +-
fs/dcache.c | 39 +-
fs/eventfd.c | 8 +-
fs/fscache/internal.h | 1 -
fs/fscache/main.c | 6 -
fs/fscache/object.c | 13 +-
fs/fuse/readdir.c | 2 +-
fs/inode.c | 2 +-
fs/namei.c | 4 +-
fs/namespace.c | 8 +-
fs/nfs/dir.c | 4 +-
fs/nfs/unlink.c | 4 +-
fs/proc/array.c | 4 +-
fs/proc/base.c | 4 +-
fs/proc/proc_sysctl.c | 2 +-
fs/pstore/platform.c | 5 +-
include/asm-generic/Kbuild | 2 +-
include/asm-generic/hardirq.h | 6 +-
include/asm-generic/kmap_size.h | 12 +
include/asm-generic/kmap_types.h | 11 -
include/asm-generic/preempt.h | 3 +
include/linux/blkdev.h | 2 +-
include/linux/bottom_half.h | 8 +-
include/linux/console.h | 11 +
include/linux/cpuhotplug.h | 1 +
include/linux/cpumask.h | 6 +
include/linux/dcache.h | 4 +-
include/linux/debug_locks.h | 3 +-
include/linux/delay.h | 6 +
include/linux/entry-common.h | 3 +-
include/linux/eventfd.h | 11 +-
include/linux/fs.h | 2 +-
include/linux/hardirq.h | 7 +-
include/linux/highmem-internal.h | 222 ++
include/linux/highmem.h | 294 +--
include/linux/interrupt.h | 34 +-
include/linux/io-mapping.h | 28 +-
include/linux/irq_cpustat.h | 28 -
include/linux/irq_work.h | 8 +
include/linux/irqdesc.h | 1 +
include/linux/irqflags.h | 23 +-
include/linux/kernel.h | 26 +-
include/linux/kmsg_dump.h | 52 +-
include/linux/local_lock_internal.h | 111 +-
include/linux/mm_types.h | 4 +
include/linux/mutex.h | 34 +-
include/linux/mutex_rt.h | 130 ++
include/linux/nfs_xdr.h | 2 +-
include/linux/notifier.h | 6 +-
include/linux/pid.h | 1 +
include/linux/preempt.h | 192 +-
include/linux/printk.h | 30 +-
include/linux/rbtree.h | 27 +-
include/linux/rbtree_type.h | 31 +
include/linux/rcupdate.h | 10 +-
include/linux/rtmutex.h | 46 +-
include/linux/rwlock_rt.h | 109 +
include/linux/rwlock_types.h | 4 +
include/linux/rwlock_types_rt.h | 56 +
include/linux/rwsem-rt.h | 70 +
include/linux/rwsem.h | 12 +
include/linux/sched.h | 127 +-
include/linux/sched/hotplug.h | 2 +
include/linux/sched/mm.h | 11 +
include/linux/sched/rt.h | 8 -
include/linux/sched/wake_q.h | 13 +-
include/linux/serial_8250.h | 5 +
include/linux/shmem_fs.h | 2 +-
include/linux/signal.h | 1 +
include/linux/skbuff.h | 7 +
include/linux/smp.h | 3 +
include/linux/spinlock.h | 12 +-
include/linux/spinlock_api_smp.h | 4 +-
include/linux/spinlock_rt.h | 155 ++
include/linux/spinlock_types.h | 92 +-
include/linux/spinlock_types_nort.h | 39 +
include/linux/spinlock_types_raw.h | 65 +
include/linux/spinlock_types_rt.h | 38 +
include/linux/spinlock_types_up.h | 2 +-
include/linux/stop_machine.h | 5 +
include/linux/thread_info.h | 12 +-
include/linux/trace_events.h | 65 +-
include/linux/u64_stats_sync.h | 42 +-
include/linux/vmstat.h | 4 +
include/linux/vtime.h | 42 +-
include/linux/wait.h | 1 +
include/linux/ww_mutex.h | 8 +
include/net/gen_stats.h | 11 +-
include/net/net_seq_lock.h | 15 +
include/net/netns/xfrm.h | 2 +-
include/net/sch_generic.h | 27 +-
include/trace/events/sched.h | 12 +
init/Kconfig | 7 +-
kernel/Kconfig.locks | 2 +-
kernel/Kconfig.preempt | 7 +
kernel/cgroup/cpuset.c | 86 +-
kernel/cgroup/rstat.c | 5 +-
kernel/cpu.c | 9 +-
kernel/debug/kdb/kdb_main.c | 10 +-
kernel/entry/common.c | 14 +-
kernel/exit.c | 2 +-
kernel/fork.c | 28 +-
kernel/futex/core.c | 87 +-
kernel/irq/handle.c | 8 +
kernel/irq/manage.c | 16 +-
kernel/irq/spurious.c | 8 +
kernel/irq_work.c | 134 +-
kernel/kexec_core.c | 1 -
kernel/ksysfs.c | 12 +
kernel/kthread.c | 16 +-
kernel/locking/Makefile | 10 +-
kernel/locking/lockdep.c | 2 +
kernel/locking/mutex-rt.c | 224 ++
kernel/locking/rtmutex-debug.c | 102 -
kernel/locking/rtmutex-debug.h | 11 -
kernel/locking/rtmutex.c | 934 +++++++--
kernel/locking/rtmutex.h | 7 -
kernel/locking/rtmutex_common.h | 36 +-
kernel/locking/rwlock-rt.c | 334 +++
kernel/locking/rwsem-rt.c | 317 +++
kernel/locking/rwsem.c | 6 +
kernel/locking/spinlock.c | 7 +
kernel/locking/spinlock_debug.c | 5 +
kernel/notifier.c | 12 +-
kernel/panic.c | 32 +-
kernel/printk/Makefile | 1 -
kernel/printk/internal.h | 4 -
kernel/printk/printk.c | 1796 +++++++++--------
kernel/printk/printk_safe.c | 349 +---
kernel/ptrace.c | 32 +-
kernel/rcu/Kconfig | 4 +-
kernel/rcu/tree.c | 4 +-
kernel/rcu/update.c | 4 +-
kernel/sched/core.c | 1276 +++++++++---
kernel/sched/cpudeadline.c | 4 +-
kernel/sched/cpupri.c | 4 +-
kernel/sched/cputime.c | 36 +-
kernel/sched/deadline.c | 47 +-
kernel/sched/fair.c | 16 +-
kernel/sched/features.h | 8 +
kernel/sched/rt.c | 83 +-
kernel/sched/sched.h | 72 +-
kernel/sched/swait.c | 1 +
kernel/sched/topology.c | 3 +-
kernel/signal.c | 105 +-
kernel/smp.c | 14 +-
kernel/softirq.c | 431 +++-
kernel/stop_machine.c | 27 +-
kernel/time/hrtimer.c | 30 +
kernel/time/tick-sched.c | 2 +-
kernel/time/timer.c | 8 +-
kernel/trace/trace.c | 93 +-
kernel/trace/trace.h | 19 -
kernel/trace/trace_events.c | 2 +
kernel/trace/trace_output.c | 19 +-
kernel/workqueue.c | 8 +-
lib/Kconfig.debug | 2 +-
lib/bug.c | 1 +
lib/cpumask.c | 18 +
lib/debugobjects.c | 4 +-
lib/dump_stack.c | 2 +
lib/irq_poll.c | 5 +
lib/locking-selftest.c | 51 +
lib/nmi_backtrace.c | 6 -
lib/scatterlist.c | 2 +-
lib/smp_processor_id.c | 5 +
lib/test_lockup.c | 16 +
mm/Kconfig | 5 +-
mm/highmem.c | 262 ++-
mm/memcontrol.c | 67 +-
mm/page_alloc.c | 180 +-
mm/shmem.c | 31 +-
mm/slab.c | 90 +-
mm/slab.h | 2 +-
mm/slub.c | 148 +-
mm/vmalloc.c | 13 +-
mm/vmstat.c | 12 +
mm/workingset.c | 5 +-
mm/z3fold.c | 17 +-
mm/zsmalloc.c | 85 +-
net/Kconfig | 2 +-
net/core/dev.c | 33 +-
net/core/gen_estimator.c | 6 +-
net/core/gen_stats.c | 12 +-
net/core/sock.c | 6 +-
net/sched/sch_api.c | 2 +-
net/sched/sch_generic.c | 10 +
net/sunrpc/svc_xprt.c | 4 +-
net/xfrm/xfrm_state.c | 3 +-
399 files changed, 8957 insertions(+), 4853 deletions(-)
delete mode 100644 arch/alpha/include/asm/kmap_types.h
delete mode 100644 arch/arc/include/asm/kmap_types.h
delete mode 100644 arch/arm/include/asm/kmap_types.h
delete mode 100644 arch/arm/mm/highmem.c
delete mode 100644 arch/ia64/include/asm/kmap_types.h
delete mode 100644 arch/microblaze/mm/highmem.c
delete mode 100644 arch/mips/include/asm/kmap_types.h
delete mode 100644 arch/nds32/mm/highmem.c
delete mode 100644 arch/parisc/include/asm/kmap_types.h
delete mode 100644 arch/powerpc/include/asm/kmap_types.h
delete mode 100644 arch/powerpc/mm/highmem.c
delete mode 100644 arch/sh/include/asm/kmap_types.h
delete mode 100644 arch/sparc/include/asm/kmap_types.h
delete mode 100644 arch/sparc/mm/highmem.c
delete mode 100644 arch/um/include/asm/kmap_types.h
delete mode 100644 arch/x86/include/asm/kmap_types.h
create mode 100644 include/asm-generic/kmap_size.h
delete mode 100644 include/asm-generic/kmap_types.h
create mode 100644 include/linux/highmem-internal.h
delete mode 100644 include/linux/irq_cpustat.h
create mode 100644 include/linux/mutex_rt.h
create mode 100644 include/linux/rbtree_type.h
create mode 100644 include/linux/rwlock_rt.h
create mode 100644 include/linux/rwlock_types_rt.h
create mode 100644 include/linux/rwsem-rt.h
create mode 100644 include/linux/spinlock_rt.h
create mode 100644 include/linux/spinlock_types_nort.h
create mode 100644 include/linux/spinlock_types_raw.h
create mode 100644 include/linux/spinlock_types_rt.h
create mode 100644 include/net/net_seq_lock.h
create mode 100644 kernel/locking/mutex-rt.c
create mode 100644 kernel/locking/rwlock-rt.c
create mode 100644 kernel/locking/rwsem-rt.c
diff --git a/Documentation/RCU/Design/Expedited-Grace-Periods/Expedited-Grace-Periods.rst b/Documentation/RCU/Design/Expedited-Grace-Periods/Expedited-Grace-Periods.rst
index 72f0f6fbd..6f89cf1e5 100644
--- a/Documentation/RCU/Design/Expedited-Grace-Periods/Expedited-Grace-Periods.rst
+++ b/Documentation/RCU/Design/Expedited-Grace-Periods/Expedited-Grace-Periods.rst
@@ -38,7 +38,7 @@ sections.
RCU-preempt Expedited Grace Periods
===================================
-``CONFIG_PREEMPT=y`` kernels implement RCU-preempt.
+``CONFIG_PREEMPTION=y`` kernels implement RCU-preempt.
The overall flow of the handling of a given CPU by an RCU-preempt
expedited grace period is shown in the following diagram:
@@ -112,7 +112,7 @@ things.
RCU-sched Expedited Grace Periods
---------------------------------
-``CONFIG_PREEMPT=n`` kernels implement RCU-sched. The overall flow of
+``CONFIG_PREEMPTION=n`` kernels implement RCU-sched. The overall flow of
the handling of a given CPU by an RCU-sched expedited grace period is
shown in the following diagram:
diff --git a/Documentation/RCU/Design/Requirements/Requirements.rst b/Documentation/RCU/Design/Requirements/Requirements.rst
index 1ae79a10a..17d38480e 100644
--- a/Documentation/RCU/Design/Requirements/Requirements.rst
+++ b/Documentation/RCU/Design/Requirements/Requirements.rst
@@ -78,7 +78,7 @@ RCU treats a nested set as one big RCU read-side critical section.
Production-quality implementations of ``rcu_read_lock()`` and
``rcu_read_unlock()`` are extremely lightweight, and in fact have
exactly zero overhead in Linux kernels built for production use with
-``CONFIG_PREEMPT=n``.
+``CONFIG_PREEMPTION=n``.
This guarantee allows ordering to be enforced with extremely low
overhead to readers, for example:
@@ -1182,7 +1182,7 @@ and has become decreasingly so as memory sizes have expanded and memory
costs have plummeted. However, as I learned from Matt Mackall's
`bloatwatch <http://elinux.org/Linux_Tiny-FAQ>`__ efforts, memory
footprint is critically important on single-CPU systems with
-non-preemptible (``CONFIG_PREEMPT=n``) kernels, and thus `tiny
+non-preemptible (``CONFIG_PREEMPTION=n``) kernels, and thus `tiny
RCU <https://lkml.kernel.org/g/20090113221724.GA15307@linux.vnet.ibm.com>`__
was born. Josh Triplett has since taken over the small-memory banner
with his `Linux kernel tinification <https://tiny.wiki.kernel.org/>`__
@@ -1498,7 +1498,7 @@ limitations.
Implementations of RCU for which ``rcu_read_lock()`` and
``rcu_read_unlock()`` generate no code, such as Linux-kernel RCU when
-``CONFIG_PREEMPT=n``, can be nested arbitrarily deeply. After all, there
+``CONFIG_PREEMPTION=n``, can be nested arbitrarily deeply. After all, there
is no overhead. Except that if all these instances of
``rcu_read_lock()`` and ``rcu_read_unlock()`` are visible to the
compiler, compilation will eventually fail due to exhausting memory,
@@ -1771,7 +1771,7 @@ implementation can be a no-op.
However, once the scheduler has spawned its first kthread, this early
boot trick fails for ``synchronize_rcu()`` (as well as for
-``synchronize_rcu_expedited()``) in ``CONFIG_PREEMPT=y`` kernels. The
+``synchronize_rcu_expedited()``) in ``CONFIG_PREEMPTION=y`` kernels. The
reason is that an RCU read-side critical section might be preempted,
which means that a subsequent ``synchronize_rcu()`` really does have to
wait for something, as opposed to simply returning immediately.
@@ -2010,7 +2010,7 @@ the following:
5 rcu_read_unlock();
6 do_something_with(v, user_v);
-If the compiler did make this transformation in a ``CONFIG_PREEMPT=n`` kernel
+If the compiler did make this transformation in a ``CONFIG_PREEMPTION=n`` kernel
build, and if ``get_user()`` did page fault, the result would be a quiescent
state in the middle of an RCU read-side critical section. This misplaced
quiescent state could result in line 4 being a use-after-free access,
@@ -2289,10 +2289,10 @@ decides to throw at it.
The Linux kernel is used for real-time workloads, especially in
conjunction with the `-rt
-patchset <https://rt.wiki.kernel.org/index.php/Main_Page>`__. The
+patchset <https://wiki.linuxfoundation.org/realtime/>`__. The
real-time-latency response requirements are such that the traditional
approach of disabling preemption across RCU read-side critical sections
-is inappropriate. Kernels built with ``CONFIG_PREEMPT=y`` therefore use
+is inappropriate. Kernels built with ``CONFIG_PREEMPTION=y`` therefore use
an RCU implementation that allows RCU read-side critical sections to be
preempted. This requirement made its presence known after users made it
clear that an earlier `real-time
@@ -2414,7 +2414,7 @@ includes ``rcu_read_lock_bh()``, ``rcu_read_unlock_bh()``,
``call_rcu_bh()``, ``rcu_barrier_bh()``, and
``rcu_read_lock_bh_held()``. However, the update-side APIs are now
simple wrappers for other RCU flavors, namely RCU-sched in
-CONFIG_PREEMPT=n kernels and RCU-preempt otherwise.
+CONFIG_PREEMPTION=n kernels and RCU-preempt otherwise.
Sched Flavor (Historical)
~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -2432,11 +2432,11 @@ not have this property, given that any point in the code outside of an
RCU read-side critical section can be a quiescent state. Therefore,
*RCU-sched* was created, which follows “classic” RCU in that an
RCU-sched grace period waits for pre-existing interrupt and NMI
-handlers. In kernels built with ``CONFIG_PREEMPT=n``, the RCU and
+handlers. In kernels built with ``CONFIG_PREEMPTION=n``, the RCU and
RCU-sched APIs have identical implementations, while kernels built with
-``CONFIG_PREEMPT=y`` provide a separate implementation for each.
+``CONFIG_PREEMPTION=y`` provide a separate implementation for each.
-Note well that in ``CONFIG_PREEMPT=y`` kernels,
+Note well that in ``CONFIG_PREEMPTION=y`` kernels,
``rcu_read_lock_sched()`` and ``rcu_read_unlock_sched()`` disable and
re-enable preemption, respectively. This means that if there was a
preemption attempt during the RCU-sched read-side critical section,
@@ -2599,10 +2599,10 @@ userspace execution also delimit tasks-RCU read-side critical sections.
The tasks-RCU API is quite compact, consisting only of
``call_rcu_tasks()``, ``synchronize_rcu_tasks()``, and
-``rcu_barrier_tasks()``. In ``CONFIG_PREEMPT=n`` kernels, trampolines
+``rcu_barrier_tasks()``. In ``CONFIG_PREEMPTION=n`` kernels, trampolines
cannot be preempted, so these APIs map to ``call_rcu()``,
``synchronize_rcu()``, and ``rcu_barrier()``, respectively. In
-``CONFIG_PREEMPT=y`` kernels, trampolines can be preempted, and these
+``CONFIG_PREEMPTION=y`` kernels, trampolines can be preempted, and these
three APIs are therefore implemented by separate functions that check
for voluntary context switches.
diff --git a/Documentation/RCU/checklist.rst b/Documentation/RCU/checklist.rst
index 2efed9926..7ed495604 100644
--- a/Documentation/RCU/checklist.rst
+++ b/Documentation/RCU/checklist.rst
@@ -214,7 +214,7 @@ over a rather long period of time, but improvements are always welcome!
the rest of the system.
7. As of v4.20, a given kernel implements only one RCU flavor,
- which is RCU-sched for PREEMPT=n and RCU-preempt for PREEMPT=y.
+ which is RCU-sched for PREEMPTION=n and RCU-preempt for PREEMPTION=y.
If the updater uses call_rcu() or synchronize_rcu(),
then the corresponding readers my use rcu_read_lock() and
rcu_read_unlock(), rcu_read_lock_bh() and rcu_read_unlock_bh(),
diff --git a/Documentation/RCU/rcubarrier.rst b/Documentation/RCU/rcubarrier.rst
index f64f4413a..3b4a24877 100644
--- a/Documentation/RCU/rcubarrier.rst
+++ b/Documentation/RCU/rcubarrier.rst
@@ -9,7 +9,7 @@ RCU (read-copy update) is a synchronization mechanism that can be thought
of as a replacement for read-writer locking (among other things), but with
very low-overhead readers that are immune to deadlock, priority inversion,
and unbounded latency. RCU read-side critical sections are delimited
-by rcu_read_lock() and rcu_read_unlock(), which, in non-CONFIG_PREEMPT
+by rcu_read_lock() and rcu_read_unlock(), which, in non-CONFIG_PREEMPTION
kernels, generate no code whatsoever.
This means that RCU writers are unaware of the presence of concurrent
@@ -329,10 +329,10 @@ Answer: This cannot happen. The reason is that on_each_cpu() has its last
to smp_call_function() and further to smp_call_function_on_cpu(),
causing this latter to spin until the cross-CPU invocation of
rcu_barrier_func() has completed. This by itself would prevent
- a grace period from completing on non-CONFIG_PREEMPT kernels,
+ a grace period from completing on non-CONFIG_PREEMPTION kernels,
since each CPU must undergo a context switch (or other quiescent
state) before the grace period can complete. However, this is
- of no use in CONFIG_PREEMPT kernels.
+ of no use in CONFIG_PREEMPTION kernels.
Therefore, on_each_cpu() disables preemption across its call
to smp_call_function() and also across the local call to
diff --git a/Documentation/RCU/stallwarn.rst b/Documentation/RCU/stallwarn.rst
index d53856cc6..7148e9be0 100644
--- a/Documentation/RCU/stallwarn.rst
+++ b/Documentation/RCU/stallwarn.rst
@@ -25,7 +25,7 @@ warnings:
- A CPU looping with bottom halves disabled.
-- For !CONFIG_PREEMPT kernels, a CPU looping anywhere in the kernel
+- For !CONFIG_PREEMPTION kernels, a CPU looping anywhere in the kernel
without invoking schedule(). If the looping in the kernel is
really expected and desirable behavior, you might need to add
some calls to cond_resched().
@@ -44,7 +44,7 @@ warnings:
result in the ``rcu_.*kthread starved for`` console-log message,
which will include additional debugging information.
-- A CPU-bound real-time task in a CONFIG_PREEMPT kernel, which might
+- A CPU-bound real-time task in a CONFIG_PREEMPTION kernel, which might
happen to preempt a low-priority task in the middle of an RCU
read-side critical section. This is especially damaging if
that low-priority task is not permitted to run on any other CPU,
diff --git a/Documentation/RCU/whatisRCU.rst b/Documentation/RCU/whatisRCU.rst
index fb3ff76c3..3b2b1479f 100644
--- a/Documentation/RCU/whatisRCU.rst
+++ b/Documentation/RCU/whatisRCU.rst
@@ -684,7 +684,7 @@ Quick Quiz #1:
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This section presents a "toy" RCU implementation that is based on
"classic RCU". It is also short on performance (but only for updates) and
-on features such as hotplug CPU and the ability to run in CONFIG_PREEMPT
+on features such as hotplug CPU and the ability to run in CONFIG_PREEMPTION
kernels. The definitions of rcu_dereference() and rcu_assign_pointer()
are the same as those shown in the preceding section, so they are omitted.
::
@@ -740,7 +740,7 @@ Quick Quiz #2:
Quick Quiz #3:
If it is illegal to block in an RCU read-side
critical section, what the heck do you do in
- PREEMPT_RT, where normal spinlocks can block???
+ CONFIG_PREEMPT_RT, where normal spinlocks can block???
:ref:`Answers to Quick Quiz <8_whatisRCU>`
@@ -1094,7 +1094,7 @@ Quick Quiz #2:
overhead is **negative**.
Answer:
- Imagine a single-CPU system with a non-CONFIG_PREEMPT
+ Imagine a single-CPU system with a non-CONFIG_PREEMPTION
kernel where a routing table is used by process-context
code, but can be updated by irq-context code (for example,
by an "ICMP REDIRECT" packet). The usual way of handling
@@ -1121,10 +1121,10 @@ Answer:
Quick Quiz #3:
If it is illegal to block in an RCU read-side
critical section, what the heck do you do in
- PREEMPT_RT, where normal spinlocks can block???
+ CONFIG_PREEMPT_RT, where normal spinlocks can block???
Answer:
- Just as PREEMPT_RT permits preemption of spinlock
+ Just as CONFIG_PREEMPT_RT permits preemption of spinlock
critical sections, it permits preemption of RCU
read-side critical sections. It also permits
spinlocks blocking while in RCU read-side critical
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 1bcc53b0c..b5249966e 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -4431,6 +4431,10 @@
value, meaning that RCU_SOFTIRQ is used by default.
Specify rcutree.use_softirq=0 to use rcuc kthreads.
+ But note that CONFIG_PREEMPT_RT=y kernels disable
+ this kernel boot parameter, forcibly setting it
+ to zero.
+
rcutree.rcu_fanout_exact= [KNL]
Disable autobalancing of the rcu_node combining
tree. This is used by rcutorture, and might
@@ -4815,6 +4819,13 @@
only normal grace-period primitives. No effect
on CONFIG_TINY_RCU kernels.
+ But note that CONFIG_PREEMPT_RT=y kernels enables
+ this kernel boot parameter, forcibly setting
+ it to the value one, that is, converting any
+ post-boot attempt at an expedited RCU grace
+ period to instead use normal non-expedited
+ grace-period processing.
+
rcupdate.rcu_task_ipi_delay= [KNL]
Set time in jiffies during which RCU tasks will
avoid sending IPIs, starting with the beginning
diff --git a/Documentation/driver-api/io-mapping.rst b/Documentation/driver-api/io-mapping.rst
index a966239f0..a7830c594 100644
--- a/Documentation/driver-api/io-mapping.rst
+++ b/Documentation/driver-api/io-mapping.rst
@@ -20,78 +20,64 @@ A mapping object is created during driver initialization using::
mappable, while 'size' indicates how large a mapping region to
enable. Both are in bytes.
-This _wc variant provides a mapping which may only be used
-with the io_mapping_map_atomic_wc or io_mapping_map_wc.
+This _wc variant provides a mapping which may only be used with
+io_mapping_map_local_wc() or io_mapping_map_wc().
-With this mapping object, individual pages can be mapped either atomically
-or not, depending on the necessary scheduling environment. Of course, atomic
-maps are more efficient::
+With this mapping object, individual pages can be mapped either temporarily
+or long term, depending on the requirements. Of course, temporary maps are
+more efficient.
- void *io_mapping_map_atomic_wc(struct io_mapping *mapping,
- unsigned long offset)
+ void *io_mapping_map_local_wc(struct io_mapping *mapping,
+ unsigned long offset)
-'offset' is the offset within the defined mapping region.
-Accessing addresses beyond the region specified in the
-creation function yields undefined results. Using an offset
-which is not page aligned yields an undefined result. The
-return value points to a single page in CPU address space.
+'offset' is the offset within the defined mapping region. Accessing
+addresses beyond the region specified in the creation function yields
+undefined results. Using an offset which is not page aligned yields an
+undefined result. The return value points to a single page in CPU address
+space.
-This _wc variant returns a write-combining map to the
-page and may only be used with mappings created by
-io_mapping_create_wc
+This _wc variant returns a write-combining map to the page and may only be
+used with mappings created by io_mapping_create_wc()
-Note that the task may not sleep while holding this page
-mapped.
+Temporary mappings are only valid in the context of the caller. The mapping
+is not guaranteed to be globaly visible.
-::
+io_mapping_map_local_wc() has a side effect on X86 32bit as it disables
+migration to make the mapping code work. No caller can rely on this side
+effect.
- void io_mapping_unmap_atomic(void *vaddr)
+Nested mappings need to be undone in reverse order because the mapping
+code uses a stack for keeping track of them::
-'vaddr' must be the value returned by the last
-io_mapping_map_atomic_wc call. This unmaps the specified
-page and allows the task to sleep once again.
+ addr1 = io_mapping_map_local_wc(map1, offset1);
+ addr2 = io_mapping_map_local_wc(map2, offset2);
+ ...
+ io_mapping_unmap_local(addr2);
+ io_mapping_unmap_local(addr1);
-If you need to sleep while holding the lock, you can use the non-atomic
-variant, although they may be significantly slower.
+The mappings are released with::
-::
+ void io_mapping_unmap_local(void *vaddr)
+
+'vaddr' must be the value returned by the last io_mapping_map_local_wc()
+call. This unmaps the specified mapping and undoes eventual side effects of
+the mapping function.
+
+If you need to sleep while holding a mapping, you can use the regular
+variant, although this may be significantly slower::
void *io_mapping_map_wc(struct io_mapping *mapping,
unsigned long offset)
-This works like io_mapping_map_atomic_wc except it allows
-the task to sleep while holding the page mapped.
+This works like io_mapping_map_local_wc() except it has no side effects and
+the pointer is globaly visible.
-
-::
+The mappings are released with::
void io_mapping_unmap(void *vaddr)
-This works like io_mapping_unmap_atomic, except it is used
-for pages mapped with io_mapping_map_wc.
+Use for pages mapped with io_mapping_map_wc().
At driver close time, the io_mapping object must be freed::
void io_mapping_free(struct io_mapping *mapping)
-
-Current Implementation
-======================
-
-The initial implementation of these functions uses existing mapping
-mechanisms and so provides only an abstraction layer and no new
-functionality.
-
-On 64-bit processors, io_mapping_create_wc calls ioremap_wc for the whole
-range, creating a permanent kernel-visible mapping to the resource. The
-map_atomic and map functions add the requested offset to the base of the
-virtual address returned by ioremap_wc.
-
-On 32-bit processors with HIGHMEM defined, io_mapping_map_atomic_wc uses
-kmap_atomic_pfn to map the specified page in an atomic fashion;
-kmap_atomic_pfn isn't really supposed to be used with device pages, but it
-provides an efficient mapping for this usage.
-
-On 32-bit processors without HIGHMEM defined, io_mapping_map_atomic_wc and
-io_mapping_map_wc both use ioremap_wc, a terribly inefficient function which
-performs an IPI to inform all processors about the new mapping. This results
-in a significant performance penalty.
diff --git a/arch/Kconfig b/arch/Kconfig
index 0fc9c6d59..0a371be43 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -50,6 +50,7 @@ config OPROFILE
tristate "OProfile system profiling"
depends on PROFILING
depends on HAVE_OPROFILE
+ depends on !PREEMPT_RT
select RING_BUFFER
select RING_BUFFER_ALLOW_SWAP
help
@@ -686,6 +687,12 @@ config HAVE_TIF_NOHZ
config HAVE_VIRT_CPU_ACCOUNTING
bool
+config HAVE_VIRT_CPU_ACCOUNTING_IDLE
+ bool
+ help
+ Architecture has its own way to account idle CPU time and therefore
+ doesn't implement vtime_account_idle().
+
config ARCH_HAS_SCALED_CPUTIME
bool
@@ -700,7 +707,6 @@ config HAVE_VIRT_CPU_ACCOUNTING_GEN
some 32-bit arches may require multiple accesses, so proper
locking is needed to protect against concurrent accesses.
-
config HAVE_IRQ_TIME_ACCOUNTING
bool
help
diff --git a/arch/alpha/include/asm/kmap_types.h b/arch/alpha/include/asm/kmap_types.h
deleted file mode 100644
index 651714b45..000000000
--- a/arch/alpha/include/asm/kmap_types.h
+++ /dev/null
@@ -1,15 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_KMAP_TYPES_H
-#define _ASM_KMAP_TYPES_H
-
-/* Dummy header just to define km_type. */
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-#define __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif
diff --git a/arch/alpha/include/asm/spinlock_types.h b/arch/alpha/include/asm/spinlock_types.h
index 1d5716bc0..6883bc952 100644
--- a/arch/alpha/include/asm/spinlock_types.h
+++ b/arch/alpha/include/asm/spinlock_types.h
@@ -2,10 +2,6 @@
#ifndef _ALPHA_SPINLOCK_TYPES_H
#define _ALPHA_SPINLOCK_TYPES_H
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
typedef struct {
volatile unsigned int lock;
} arch_spinlock_t;
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index 0a89cc9de..d8804001d 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -507,6 +507,7 @@ config LINUX_RAM_BASE
config HIGHMEM
bool "High Memory Support"
select ARCH_DISCONTIGMEM_ENABLE
+ select KMAP_LOCAL
help
With ARC 2G:2G address split, only upper 2G is directly addressable by
kernel. Enable this to potentially allow access to rest of 2G and PAE
diff --git a/arch/arc/include/asm/highmem.h b/arch/arc/include/asm/highmem.h
index 6e5eafb3a..a6b8e2c35 100644
--- a/arch/arc/include/asm/highmem.h
+++ b/arch/arc/include/asm/highmem.h
@@ -9,17 +9,29 @@
#ifdef CONFIG_HIGHMEM
#include <uapi/asm/page.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
+
+#define FIXMAP_SIZE PGDIR_SIZE
+#define PKMAP_SIZE PGDIR_SIZE
/* start after vmalloc area */
#define FIXMAP_BASE (PAGE_OFFSET - FIXMAP_SIZE - PKMAP_SIZE)
-#define FIXMAP_SIZE PGDIR_SIZE /* only 1 PGD worth */
-#define KM_TYPE_NR ((FIXMAP_SIZE >> PAGE_SHIFT)/NR_CPUS)
-#define FIXMAP_ADDR(nr) (FIXMAP_BASE + ((nr) << PAGE_SHIFT))
+
+#define FIX_KMAP_SLOTS (KM_MAX_IDX * NR_CPUS)
+#define FIX_KMAP_BEGIN (0UL)
+#define FIX_KMAP_END ((FIX_KMAP_BEGIN + FIX_KMAP_SLOTS) - 1)
+
+#define FIXADDR_TOP (FIXMAP_BASE + (FIX_KMAP_END << PAGE_SHIFT))
+
+/*
+ * This should be converted to the asm-generic version, but of course this
+ * is needlessly different from all other architectures. Sigh - tglx
+ */
+#define __fix_to_virt(x) (FIXADDR_TOP - ((x) << PAGE_SHIFT))
+#define __virt_to_fix(x) (((FIXADDR_TOP - ((x) & PAGE_MASK))) >> PAGE_SHIFT)
/* start after fixmap area */
#define PKMAP_BASE (FIXMAP_BASE + FIXMAP_SIZE)
-#define PKMAP_SIZE PGDIR_SIZE
#define LAST_PKMAP (PKMAP_SIZE >> PAGE_SHIFT)
#define LAST_PKMAP_MASK (LAST_PKMAP - 1)
#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
@@ -29,11 +41,13 @@
extern void kmap_init(void);
+#define arch_kmap_local_post_unmap(vaddr) \
+ local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE)
+
static inline void flush_cache_kmaps(void)
{
flush_cache_all();
}
-
#endif
#endif
diff --git a/arch/arc/include/asm/kmap_types.h b/arch/arc/include/asm/kmap_types.h
deleted file mode 100644
index fecf7851e..000000000
--- a/arch/arc/include/asm/kmap_types.h
+++ /dev/null
@@ -1,14 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (C) 2015 Synopsys, Inc. (www.synopsys.com)
- */
-
-#ifndef _ASM_KMAP_TYPES_H
-#define _ASM_KMAP_TYPES_H
-
-/*
- * We primarily need to define KM_TYPE_NR here but that in turn
- * is a function of PGDIR_SIZE etc.
- * To avoid circular deps issue, put everything in asm/highmem.h
- */
-#endif
diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c
index 1b9f473c6..c79912a6b 100644
--- a/arch/arc/mm/highmem.c
+++ b/arch/arc/mm/highmem.c
@@ -36,9 +36,8 @@
* This means each only has 1 PGDIR_SIZE worth of kvaddr mappings, which means
* 2M of kvaddr space for typical config (8K page and 11:8:13 traversal split)
*
- * - fixmap anyhow needs a limited number of mappings. So 2M kvaddr == 256 PTE
- * slots across NR_CPUS would be more than sufficient (generic code defines
- * KM_TYPE_NR as 20).
+ * - The fixed KMAP slots for kmap_local/atomic() require KM_MAX_IDX slots per
+ * CPU. So the number of CPUs sharing a single PTE page is limited.
*
* - pkmap being preemptible, in theory could do with more than 256 concurrent
* mappings. However, generic pkmap code: map_new_virtual(), doesn't traverse
@@ -47,48 +46,6 @@
*/
extern pte_t * pkmap_page_table;
-static pte_t * fixmap_page_table;
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
- int idx, cpu_idx;
- unsigned long vaddr;
-
- cpu_idx = kmap_atomic_idx_push();
- idx = cpu_idx + KM_TYPE_NR * smp_processor_id();
- vaddr = FIXMAP_ADDR(idx);
-
- set_pte_at(&init_mm, vaddr, fixmap_page_table + idx,
- mk_pte(page, prot));
-
- return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kv)
-{
- unsigned long kvaddr = (unsigned long)kv;
-
- if (kvaddr >= FIXMAP_BASE && kvaddr < (FIXMAP_BASE + FIXMAP_SIZE)) {
-
- /*
- * Because preemption is disabled, this vaddr can be associated
- * with the current allocated index.
- * But in case of multiple live kmap_atomic(), it still relies on
- * callers to unmap in right order.
- */
- int cpu_idx = kmap_atomic_idx();
- int idx = cpu_idx + KM_TYPE_NR * smp_processor_id();
-
- WARN_ON(kvaddr != FIXMAP_ADDR(idx));
-
- pte_clear(&init_mm, kvaddr, fixmap_page_table + idx);
- local_flush_tlb_kernel_range(kvaddr, kvaddr + PAGE_SIZE);
-
- kmap_atomic_idx_pop();
- }
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
static noinline pte_t * __init alloc_kmap_pgtable(unsigned long kvaddr)
{
@@ -108,10 +65,9 @@ void __init kmap_init(void)
{
/* Due to recursive include hell, we can't do this in processor.h */
BUILD_BUG_ON(PAGE_OFFSET < (VMALLOC_END + FIXMAP_SIZE + PKMAP_SIZE));
+ BUILD_BUG_ON(LAST_PKMAP > PTRS_PER_PTE);
+ BUILD_BUG_ON(FIX_KMAP_SLOTS > PTRS_PER_PTE);
- BUILD_BUG_ON(KM_TYPE_NR > PTRS_PER_PTE);
pkmap_page_table = alloc_kmap_pgtable(PKMAP_BASE);
-
- BUILD_BUG_ON(LAST_PKMAP > PTRS_PER_PTE);
- fixmap_page_table = alloc_kmap_pgtable(FIXMAP_BASE);
+ alloc_kmap_pgtable(FIXMAP_BASE);
}
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 370b9048e..0b80f42f5 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -32,6 +32,7 @@ config ARM
select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if CPU_V7
select ARCH_SUPPORTS_ATOMIC_RMW
+ select ARCH_SUPPORTS_RT if HAVE_POSIX_CPU_TIMERS_TASK_WORK
select ARCH_USE_BUILTIN_BSWAP
select ARCH_USE_CMPXCHG_LOCKREF
select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
@@ -67,7 +68,7 @@ config ARM
select HARDIRQS_SW_RESEND
select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT
select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
- select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
+ select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU && !PREEMPT_RT
select HAVE_ARCH_KFENCE if MMU
select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL
@@ -110,6 +111,7 @@ config ARM
select HAVE_PERF_EVENTS
select HAVE_PERF_REGS
select HAVE_PERF_USER_STACK_DUMP
+ select HAVE_PREEMPT_LAZY
select MMU_GATHER_RCU_TABLE_FREE if SMP && ARM_LPAE
select HAVE_REGS_AND_STACK_ACCESS_API
select HAVE_RSEQ
@@ -125,6 +127,7 @@ config ARM
select OLD_SIGSUSPEND3
select PCI_SYSCALL if PCI
select PERF_USE_VMALLOC
+ select HAVE_POSIX_CPU_TIMERS_TASK_WORK if !KVM
select RTC_LIB
select SET_FS
select SYS_SUPPORTS_APM_EMULATION
@@ -1521,6 +1524,7 @@ config HAVE_ARCH_PFN_VALID
config HIGHMEM
bool "High Memory Support"
depends on MMU
+ select KMAP_LOCAL
help
The address space of ARM processors is only 4 Gigabytes large
and it has to accommodate user address space, kernel address
diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h
index 9575b4040..707068f85 100644
--- a/arch/arm/include/asm/fixmap.h
+++ b/arch/arm/include/asm/fixmap.h
@@ -7,14 +7,14 @@
#define FIXADDR_TOP (FIXADDR_END - PAGE_SIZE)
#include <linux/pgtable.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
enum fixed_addresses {
FIX_EARLYCON_MEM_BASE,
__end_of_permanent_fixed_addresses,
FIX_KMAP_BEGIN = __end_of_permanent_fixed_addresses,
- FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
+ FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
/* Support writing RO kernel text via kprobes, jump labels, etc. */
FIX_TEXT_POKE0,
diff --git a/arch/arm/include/asm/hardirq.h b/arch/arm/include/asm/hardirq.h
index b95848ed2..706efafbf 100644
--- a/arch/arm/include/asm/hardirq.h
+++ b/arch/arm/include/asm/hardirq.h
@@ -2,16 +2,11 @@
#ifndef __ASM_HARDIRQ_H
#define __ASM_HARDIRQ_H
-#include <linux/cache.h>
-#include <linux/threads.h>
#include <asm/irq.h>
-typedef struct {
- unsigned int __softirq_pending;
-} ____cacheline_aligned irq_cpustat_t;
-
-#include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
-
#define __ARCH_IRQ_EXIT_IRQS_DISABLED 1
+#define ack_bad_irq ack_bad_irq
+
+#include <asm-generic/hardirq.h>
#endif /* __ASM_HARDIRQ_H */
diff --git a/arch/arm/include/asm/highmem.h b/arch/arm/include/asm/highmem.h
index 31811be38..b22dffa8c 100644
--- a/arch/arm/include/asm/highmem.h
+++ b/arch/arm/include/asm/highmem.h
@@ -2,7 +2,8 @@
#ifndef _ASM_HIGHMEM_H
#define _ASM_HIGHMEM_H
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
+#include <asm/fixmap.h>
#define PKMAP_BASE (PAGE_OFFSET - PMD_SIZE)
#define LAST_PKMAP PTRS_PER_PTE
@@ -46,19 +47,32 @@ extern pte_t *pkmap_page_table;
#ifdef ARCH_NEEDS_KMAP_HIGH_GET
extern void *kmap_high_get(struct page *page);
-#else
+
+static inline void *arch_kmap_local_high_get(struct page *page)
+{
+ if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !cache_is_vivt())
+ return NULL;
+ return kmap_high_get(page);
+}
+#define arch_kmap_local_high_get arch_kmap_local_high_get
+
+#else /* ARCH_NEEDS_KMAP_HIGH_GET */
static inline void *kmap_high_get(struct page *page)
{
return NULL;
}
-#endif
+#endif /* !ARCH_NEEDS_KMAP_HIGH_GET */
-/*
- * The following functions are already defined by <linux/highmem.h>
- * when CONFIG_HIGHMEM is not set.
- */
-#ifdef CONFIG_HIGHMEM
-extern void *kmap_atomic_pfn(unsigned long pfn);
-#endif
+#define arch_kmap_local_post_map(vaddr, pteval) \
+ local_flush_tlb_kernel_page(vaddr)
+
+#define arch_kmap_local_pre_unmap(vaddr) \
+do { \
+ if (cache_is_vivt()) \
+ __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE); \
+} while (0)
+
+#define arch_kmap_local_post_unmap(vaddr) \
+ local_flush_tlb_kernel_page(vaddr)
#endif
diff --git a/arch/arm/include/asm/irq.h b/arch/arm/include/asm/irq.h
index 54b0180c8..36d040c68 100644
--- a/arch/arm/include/asm/irq.h
+++ b/arch/arm/include/asm/irq.h
@@ -31,6 +31,8 @@ void handle_IRQ(unsigned int, struct pt_regs *);
void init_IRQ(void);
#ifdef CONFIG_SMP
+#include <linux/cpumask.h>
+
extern bool arch_trigger_cpumask_backtrace(const cpumask_t *mask,
bool exclude_self);
#define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace
diff --git a/arch/arm/include/asm/kmap_types.h b/arch/arm/include/asm/kmap_types.h
deleted file mode 100644
index 5590940ee..000000000
--- a/arch/arm/include/asm/kmap_types.h
+++ /dev/null
@@ -1,10 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __ARM_KMAP_TYPES_H
-#define __ARM_KMAP_TYPES_H
-
-/*
- * This is the "bare minimum". AIO seems to require this.
- */
-#define KM_TYPE_NR 16
-
-#endif
diff --git a/arch/arm/include/asm/spinlock_types.h b/arch/arm/include/asm/spinlock_types.h
index 597695864..a37c08039 100644
--- a/arch/arm/include/asm/spinlock_types.h
+++ b/arch/arm/include/asm/spinlock_types.h
@@ -2,10 +2,6 @@
#ifndef __ASM_SPINLOCK_TYPES_H
#define __ASM_SPINLOCK_TYPES_H
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
#define TICKET_SHIFT 16
typedef struct {
diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h
index 16bcc6f36..ac682026a 100644
--- a/arch/arm/include/asm/thread_info.h
+++ b/arch/arm/include/asm/thread_info.h
@@ -55,6 +55,7 @@ struct cpu_context_save {
struct thread_info {
unsigned long flags; /* low level flags */
int preempt_count; /* 0 => preemptable, <0 => bug */
+ int preempt_lazy_count; /* 0 => preemptable, <0 => bug */
mm_segment_t addr_limit; /* address limit */
struct task_struct *task; /* main task structure */
__u32 cpu; /* cpu */
@@ -145,6 +146,7 @@ extern int vfp_restore_user_hwstate(struct user_vfp *,
#define TIF_NOTIFY_RESUME 2 /* callback before returning to user */
#define TIF_UPROBE 3 /* breakpointed or singlestepping */
#define TIF_NOTIFY_SIGNAL 4 /* signal notifications exist */
+#define TIF_NEED_RESCHED_LAZY 7
#define TIF_PATCH_PENDING 8 /* pending live patching update */
#define TIF_USING_IWMMXT 17
@@ -159,6 +161,7 @@ extern int vfp_restore_user_hwstate(struct user_vfp *,
#define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
#define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
+#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY)
#define _TIF_UPROBE (1 << TIF_UPROBE)
#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
#define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
@@ -176,7 +179,7 @@ extern int vfp_restore_user_hwstate(struct user_vfp *,
* Change these and you break ASM code in entry-common.S
*/
#define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
- _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
+ _TIF_NOTIFY_RESUME | _TIF_UPROBE | _TIF_NEED_RESCHED_LAZY | \
_TIF_NOTIFY_SIGNAL)
#endif /* __KERNEL__ */
diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
index 70993af22..024c65c3a 100644
--- a/arch/arm/kernel/asm-offsets.c
+++ b/arch/arm/kernel/asm-offsets.c
@@ -43,6 +43,7 @@ int main(void)
BLANK();
DEFINE(TI_FLAGS, offsetof(struct thread_info, flags));
DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count));
+ DEFINE(TI_PREEMPT_LAZY, offsetof(struct thread_info, preempt_lazy_count));
DEFINE(TI_ADDR_LIMIT, offsetof(struct thread_info, addr_limit));
DEFINE(TI_TASK, offsetof(struct thread_info, task));
DEFINE(TI_CPU, offsetof(struct thread_info, cpu));
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index 4332e5950..efb2d0755 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -207,11 +207,18 @@ __irq_svc:
#ifdef CONFIG_PREEMPTION
ldr r8, [tsk, #TI_PREEMPT] @ get preempt count
- ldr r0, [tsk, #TI_FLAGS] @ get flags
teq r8, #0 @ if preempt count != 0
+ bne 1f @ return from exeption
+ ldr r0, [tsk, #TI_FLAGS] @ get flags
+ tst r0, #_TIF_NEED_RESCHED @ if NEED_RESCHED is set
+ blne svc_preempt @ preempt!
+
+ ldr r8, [tsk, #TI_PREEMPT_LAZY] @ get preempt lazy count
+ teq r8, #0 @ if preempt lazy count != 0
movne r0, #0 @ force flags to 0
- tst r0, #_TIF_NEED_RESCHED
+ tst r0, #_TIF_NEED_RESCHED_LAZY
blne svc_preempt
+1:
#endif
svc_exit r5, irq = 1 @ return from exception
@@ -226,8 +233,14 @@ svc_preempt:
1: bl preempt_schedule_irq @ irq en/disable is done inside
ldr r0, [tsk, #TI_FLAGS] @ get new tasks TI_FLAGS
tst r0, #_TIF_NEED_RESCHED
+ bne 1b
+ tst r0, #_TIF_NEED_RESCHED_LAZY
reteq r8 @ go again
- b 1b
+ ldr r0, [tsk, #TI_PREEMPT_LAZY] @ get preempt lazy count
+ teq r0, #0 @ if preempt lazy count != 0
+ beq 1b
+ ret r8 @ go again
+
#endif
__und_fault:
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index a3a38d0a4..f04ccf19a 100644
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -649,7 +649,8 @@ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall)
*/
trace_hardirqs_off();
do {
- if (likely(thread_flags & _TIF_NEED_RESCHED)) {
+ if (likely(thread_flags & (_TIF_NEED_RESCHED |
+ _TIF_NEED_RESCHED_LAZY))) {
schedule();
} else {
if (unlikely(!user_mode(regs)))
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index d94e39a21..44383bfbf 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -671,9 +671,7 @@ static void do_handle_IPI(int ipinr)
break;
case IPI_CPU_BACKTRACE:
- printk_nmi_enter();
nmi_cpu_backtrace(get_irq_regs());
- printk_nmi_exit();
break;
default:
diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile
index 4536159bc..3510503bc 100644
--- a/arch/arm/mm/Makefile
+++ b/arch/arm/mm/Makefile
@@ -21,7 +21,6 @@ KASAN_SANITIZE_physaddr.o := n
obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o
obj-$(CONFIG_ALIGNMENT_TRAP) += alignment.o
-obj-$(CONFIG_HIGHMEM) += highmem.o
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
obj-$(CONFIG_ARM_PV_FIXUP) += pv-fixup-asm.o
diff --git a/arch/arm/mm/cache-feroceon-l2.c b/arch/arm/mm/cache-feroceon-l2.c
index 10f909744..fd9e3e740 100644
--- a/arch/arm/mm/cache-feroceon-l2.c
+++ b/arch/arm/mm/cache-feroceon-l2.c
@@ -49,9 +49,9 @@ static inline unsigned long l2_get_va(unsigned long paddr)
* we simply install a virtual mapping for it only for the
* TLB lookup to occur, hence no need to flush the untouched
* memory mapping afterwards (note: a cache flush may happen
- * in some circumstances depending on the path taken in kunmap_atomic).
+ * in some circumstances depending on the path taken in kunmap_local).
*/
- void *vaddr = kmap_atomic_pfn(paddr >> PAGE_SHIFT);
+ void *vaddr = kmap_local_pfn(paddr >> PAGE_SHIFT);
return (unsigned long)vaddr + (paddr & ~PAGE_MASK);
#else
return __phys_to_virt(paddr);
@@ -61,7 +61,7 @@ static inline unsigned long l2_get_va(unsigned long paddr)
static inline void l2_put_va(unsigned long vaddr)
{
#ifdef CONFIG_HIGHMEM
- kunmap_atomic((void *)vaddr);
+ kunmap_local((void *)vaddr);
#endif
}
diff --git a/arch/arm/mm/cache-xsc3l2.c b/arch/arm/mm/cache-xsc3l2.c
index 581473165..f34845da3 100644
--- a/arch/arm/mm/cache-xsc3l2.c
+++ b/arch/arm/mm/cache-xsc3l2.c
@@ -59,7 +59,7 @@ static inline void l2_unmap_va(unsigned long va)
{
#ifdef CONFIG_HIGHMEM
if (va != -1)
- kunmap_atomic((void *)va);
+ kunmap_local((void *)va);
#endif
}
@@ -75,7 +75,7 @@ static inline unsigned long l2_map_va(unsigned long pa, unsigned long prev_va)
* in place for it.
*/
l2_unmap_va(prev_va);
- va = (unsigned long)kmap_atomic_pfn(pa >> PAGE_SHIFT);
+ va = (unsigned long)kmap_local_pfn(pa >> PAGE_SHIFT);
}
return va + (pa_offset >> (32 - PAGE_SHIFT));
#else
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 4c64d9015..f068759a3 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -444,6 +444,9 @@ do_translation_fault(unsigned long addr, unsigned int fsr,
if (addr < TASK_SIZE)
return do_page_fault(addr, fsr, regs);
+ if (interrupts_enabled(regs))
+ local_irq_enable();
+
if (user_mode(regs))
goto bad_area;
diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
deleted file mode 100644
index 187fab227..000000000
--- a/arch/arm/mm/highmem.c
+++ /dev/null
@@ -1,121 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * arch/arm/mm/highmem.c -- ARM highmem support
- *
- * Author: Nicolas Pitre
- * Created: september 8, 2008
- * Copyright: Marvell Semiconductors Inc.
- */
-
-#include <linux/module.h>
-#include <linux/highmem.h>
-#include <linux/interrupt.h>
-#include <asm/fixmap.h>
-#include <asm/cacheflush.h>
-#include <asm/tlbflush.h>
-#include "mm.h"
-
-static inline void set_fixmap_pte(int idx, pte_t pte)
-{
- unsigned long vaddr = __fix_to_virt(idx);
- pte_t *ptep = virt_to_kpte(vaddr);
-
- set_pte_ext(ptep, pte, 0);
- local_flush_tlb_kernel_page(vaddr);
-}
-
-static inline pte_t get_fixmap_pte(unsigned long vaddr)
-{
- pte_t *ptep = virt_to_kpte(vaddr);
-
- return *ptep;
-}
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
- unsigned int idx;
- unsigned long vaddr;
- void *kmap;
- int type;
-
-#ifdef CONFIG_DEBUG_HIGHMEM
- /*
- * There is no cache coherency issue when non VIVT, so force the
- * dedicated kmap usage for better debugging purposes in that case.
- */
- if (!cache_is_vivt())
- kmap = NULL;
- else
-#endif
- kmap = kmap_high_get(page);
- if (kmap)
- return kmap;
-
- type = kmap_atomic_idx_push();
-
- idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
- vaddr = __fix_to_virt(idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
- /*
- * With debugging enabled, kunmap_atomic forces that entry to 0.
- * Make sure it was indeed properly unmapped.
- */
- BUG_ON(!pte_none(get_fixmap_pte(vaddr)));
-#endif
- /*
- * When debugging is off, kunmap_atomic leaves the previous mapping
- * in place, so the contained TLB flush ensures the TLB is updated
- * with the new mapping.
- */
- set_fixmap_pte(idx, mk_pte(page, prot));
-
- return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
- unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
- int idx, type;
-
- if (kvaddr >= (void *)FIXADDR_START) {
- type = kmap_atomic_idx();
- idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
-
- if (cache_is_vivt())
- __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);
-#ifdef CONFIG_DEBUG_HIGHMEM
- BUG_ON(vaddr != __fix_to_virt(idx));
- set_fixmap_pte(idx, __pte(0));
-#else
- (void) idx; /* to kill a warning */
-#endif
- kmap_atomic_idx_pop();
- } else if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) {
- /* this address was obtained through kmap_high_get() */
- kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)]));
- }
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
-
-void *kmap_atomic_pfn(unsigned long pfn)
-{
- unsigned long vaddr;
- int idx, type;
- struct page *page = pfn_to_page(pfn);
-
- preempt_disable();
- pagefault_disable();
- if (!PageHighMem(page))
- return page_address(page);
-
- type = kmap_atomic_idx_push();
- idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
- vaddr = __fix_to_virt(idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
- BUG_ON(!pte_none(get_fixmap_pte(vaddr)));
-#endif
- set_fixmap_pte(idx, pfn_pte(pfn, kmap_prot));
-
- return (void *)vaddr;
-}
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index c57dfa479..2fa733957 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -78,6 +78,7 @@ config ARM64
select ARCH_SUPPORTS_ATOMIC_RMW
select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && (GCC_VERSION >= 50000 || CC_IS_CLANG)
select ARCH_SUPPORTS_NUMA_BALANCING
+ select ARCH_SUPPORTS_RT if HAVE_POSIX_CPU_TIMERS_TASK_WORK
select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
select ARCH_WANT_DEFAULT_BPF_JIT
@@ -186,6 +187,7 @@ config ARM64
select HAVE_PERF_EVENTS
select HAVE_PERF_REGS
select HAVE_PERF_USER_STACK_DUMP
+ select HAVE_PREEMPT_LAZY
select HAVE_REGS_AND_STACK_ACCESS_API
select HAVE_FUNCTION_ARG_ACCESS_API
select HAVE_FUTEX_CMPXCHG if FUTEX
@@ -210,6 +212,7 @@ config ARM64
select PCI_DOMAINS_GENERIC if PCI
select PCI_ECAM if (ACPI && PCI)
select PCI_SYSCALL if PCI
+ select HAVE_POSIX_CPU_TIMERS_TASK_WORK if !KVM
select POWER_RESET
select POWER_SUPPLY
select SPARSE_IRQ
diff --git a/arch/arm64/include/asm/hardirq.h b/arch/arm64/include/asm/hardirq.h
index 5ffa4bacd..cbfa7b6f2 100644
--- a/arch/arm64/include/asm/hardirq.h
+++ b/arch/arm64/include/asm/hardirq.h
@@ -13,11 +13,8 @@
#include <asm/kvm_arm.h>
#include <asm/sysreg.h>
-typedef struct {
- unsigned int __softirq_pending;
-} ____cacheline_aligned irq_cpustat_t;
-
-#include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
+#define ack_bad_irq ack_bad_irq
+#include <asm-generic/hardirq.h>
#define __ARCH_IRQ_EXIT_IRQS_DISABLED 1
diff --git a/arch/arm64/include/asm/preempt.h b/arch/arm64/include/asm/preempt.h
index e83f0982b..7a5770d82 100644
--- a/arch/arm64/include/asm/preempt.h
+++ b/arch/arm64/include/asm/preempt.h
@@ -70,17 +70,43 @@ static inline bool __preempt_count_dec_and_test(void)
* interrupt occurring between the non-atomic READ_ONCE/WRITE_ONCE
* pair.
*/
- return !pc || !READ_ONCE(ti->preempt_count);
+ if (!pc || !READ_ONCE(ti->preempt_count))
+ return true;
+#ifdef CONFIG_PREEMPT_LAZY
+ if ((pc & ~PREEMPT_NEED_RESCHED))
+ return false;
+ if (current_thread_info()->preempt_lazy_count)
+ return false;
+ return test_thread_flag(TIF_NEED_RESCHED_LAZY);
+#else
+ return false;
+#endif
}
static inline bool should_resched(int preempt_offset)
{
+#ifdef CONFIG_PREEMPT_LAZY
+ u64 pc = READ_ONCE(current_thread_info()->preempt_count);
+ if (pc == preempt_offset)
+ return true;
+
+ if ((pc & ~PREEMPT_NEED_RESCHED) != preempt_offset)
+ return false;
+
+ if (current_thread_info()->preempt_lazy_count)
+ return false;
+ return test_thread_flag(TIF_NEED_RESCHED_LAZY);
+#else
u64 pc = READ_ONCE(current_thread_info()->preempt_count);
return pc == preempt_offset;
+#endif
}
#ifdef CONFIG_PREEMPTION
void preempt_schedule(void);
+#ifdef CONFIG_PREEMPT_RT
+void preempt_schedule_lock(void);
+#endif
#define __preempt_schedule() preempt_schedule()
void preempt_schedule_notrace(void);
#define __preempt_schedule_notrace() preempt_schedule_notrace()
diff --git a/arch/arm64/include/asm/spinlock_types.h b/arch/arm64/include/asm/spinlock_types.h
index 18782f0c4..6672b0535 100644
--- a/arch/arm64/include/asm/spinlock_types.h
+++ b/arch/arm64/include/asm/spinlock_types.h
@@ -5,10 +5,6 @@
#ifndef __ASM_SPINLOCK_TYPES_H
#define __ASM_SPINLOCK_TYPES_H
-#if !defined(__LINUX_SPINLOCK_TYPES_H) && !defined(__ASM_SPINLOCK_H)
-# error "please don't include this file directly"
-#endif
-
#include <asm-generic/qspinlock_types.h>
#include <asm-generic/qrwlock_types.h>
diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h
index 390d96125..531420502 100644
--- a/arch/arm64/include/asm/thread_info.h
+++ b/arch/arm64/include/asm/thread_info.h
@@ -27,6 +27,7 @@ struct thread_info {
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
u64 ttbr0; /* saved TTBR0_EL1 */
#endif
+ int preempt_lazy_count; /* 0 => preemptable, <0 => bug */
union {
u64 preempt_count; /* 0 => preemptible, <0 => bug */
struct {
@@ -70,6 +71,7 @@ void arch_release_task_struct(struct task_struct *tsk);
#define TIF_UPROBE 4 /* uprobe breakpoint or singlestep */
#define TIF_MTE_ASYNC_FAULT 5 /* MTE Asynchronous Tag Check Fault */
#define TIF_NOTIFY_SIGNAL 6 /* signal notifications exist */
+#define TIF_NEED_RESCHED_LAZY 7
#define TIF_SYSCALL_TRACE 8 /* syscall trace active */
#define TIF_SYSCALL_AUDIT 9 /* syscall auditing */
#define TIF_SYSCALL_TRACEPOINT 10 /* syscall tracepoint for ftrace */
@@ -104,6 +106,7 @@ void arch_release_task_struct(struct task_struct *tsk);
#define _TIF_32BIT (1 << TIF_32BIT)
#define _TIF_SVE (1 << TIF_SVE)
#define _TIF_MTE_ASYNC_FAULT (1 << TIF_MTE_ASYNC_FAULT)
+#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY)
#define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL)
#define _TIF_32BIT_AARCH64 (1 << TIF_32BIT_AARCH64)
#define _TIF_PATCH_PENDING (1 << TIF_PATCH_PENDING)
@@ -111,9 +114,12 @@ void arch_release_task_struct(struct task_struct *tsk);
#define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
_TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \
- _TIF_UPROBE | _TIF_MTE_ASYNC_FAULT | \
+ _TIF_UPROBE | _TIF_MTE_ASYNC_FAULT | _TIF_NEED_RESCHED_LAZY |\
_TIF_NOTIFY_SIGNAL)
+
+#define _TIF_NEED_RESCHED_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)
+
#define _TIF_SYSCALL_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
_TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \
_TIF_SYSCALL_EMU)
diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
index c247e1113..a15c83111 100644
--- a/arch/arm64/kernel/asm-offsets.c
+++ b/arch/arm64/kernel/asm-offsets.c
@@ -31,6 +31,7 @@ int main(void)
DEFINE(TSK_TI_CPU, offsetof(struct task_struct, thread_info.cpu));
DEFINE(TSK_TI_FLAGS, offsetof(struct task_struct, thread_info.flags));
DEFINE(TSK_TI_PREEMPT, offsetof(struct task_struct, thread_info.preempt_count));
+ DEFINE(TSK_TI_PREEMPT_LAZY, offsetof(struct task_struct, thread_info.preempt_lazy_count));
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
DEFINE(TSK_TI_TTBR0, offsetof(struct task_struct, thread_info.ttbr0));
#endif
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index eb4ba8308..cf0c9fbed 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -521,9 +521,18 @@ alternative_if ARM64_HAS_IRQ_PRIO_MASKING
orr x24, x24, x0
alternative_else_nop_endif
#endif
- cbnz x24, 1f // preempt count != 0 || NMI return path
- bl arm64_preempt_schedule_irq // irq en/disable is done inside
+
+ cbz x24, 1f // (need_resched + count) == 0
+ cbnz w24, 2f // count != 0
+
+ ldr w24, [tsk, #TSK_TI_PREEMPT_LAZY] // get preempt lazy count
+ cbnz w24, 2f // preempt lazy count != 0
+
+ ldr x0, [tsk, #TSK_TI_FLAGS] // get flags
+ tbz x0, #TIF_NEED_RESCHED_LAZY, 2f // needs rescheduling?
1:
+ bl arm64_preempt_schedule_irq // irq en/disable is done inside
+2:
#endif
mov x0, sp
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
index c2489a72b..131b2dda3 100644
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -313,6 +313,15 @@ void task_set_vl_onexec(struct task_struct *task, enum vec_type type,
* may disable TIF_SME and reenable traps.
*/
+static void *sve_free_atomic(struct task_struct *task)
+{
+ void *sve_state = task->thread.sve_state;
+
+ WARN_ON(test_tsk_thread_flag(task, TIF_SVE));
+
+ task->thread.sve_state = NULL;
+ return sve_state;
+}
/*
* TIF_SVE controls whether a task can use SVE without trapping while
@@ -1556,6 +1565,7 @@ static void fpsimd_flush_thread_vl(enum vec_type type)
void fpsimd_flush_thread(void)
{
+ void *mem = NULL;
if (!system_supports_fpsimd())
return;
@@ -1567,7 +1577,7 @@ void fpsimd_flush_thread(void)
if (system_supports_sve()) {
clear_thread_flag(TIF_SVE);
- sve_free(current);
+ mem = sve_free_atomic(current);
fpsimd_flush_thread_vl(ARM64_VEC_SVE);
}
@@ -1579,6 +1589,7 @@ void fpsimd_flush_thread(void)
}
put_cpu_fpsimd_context();
+ kfree(mem);
}
/*
diff --git a/arch/arm64/kernel/ipi_nmi.c b/arch/arm64/kernel/ipi_nmi.c
index 9a8f7c256..c0753dcdb 100644
--- a/arch/arm64/kernel/ipi_nmi.c
+++ b/arch/arm64/kernel/ipi_nmi.c
@@ -35,9 +35,7 @@ void arm64_send_nmi(cpumask_t *mask)
static void ipi_cpu_backtrace(void *info)
{
- printk_safe_enter();
nmi_cpu_backtrace(get_irq_regs());
- printk_safe_exit();
}
static DEFINE_PER_CPU(call_single_data_t, cpu_backtrace_csd) =
diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
index a0c85bb01..d315329ba 100644
--- a/arch/arm64/kernel/signal.c
+++ b/arch/arm64/kernel/signal.c
@@ -861,7 +861,7 @@ asmlinkage void do_notify_resume(struct pt_regs *regs,
unsigned long thread_flags)
{
do {
- if (thread_flags & _TIF_NEED_RESCHED) {
+ if (thread_flags & _TIF_NEED_RESCHED_MASK) {
/* Unmask Debug and SError for the next task */
local_daif_restore(DAIF_PROCCTX_NOIRQ);
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 11a2c3b0e..2683be020 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -957,7 +957,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
* involves poking the GIC, which must be done in a
* non-preemptible context.
*/
- preempt_disable();
+ migrate_disable();
kvm_pmu_flush_hwstate(vcpu);
#ifdef CONFIG_CVM_HOST
@@ -985,7 +985,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
kvm_timer_sync_user(vcpu);
kvm_vgic_sync_hwstate(vcpu);
local_irq_enable();
- preempt_enable();
+ migrate_enable();
continue;
}
@@ -1073,7 +1073,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
#ifdef CONFIG_CVM_HOST
}
#endif
- preempt_enable();
+ migrate_enable();
#ifdef CONFIG_CVM_HOST
if (pmu_stopped)
arm_pmu_set_phys_irq(true);
diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
index 7bf0a617e..c9f2533cc 100644
--- a/arch/csky/Kconfig
+++ b/arch/csky/Kconfig
@@ -286,6 +286,7 @@ config NR_CPUS
config HIGHMEM
bool "High Memory Support"
depends on !CPU_CK610
+ select KMAP_LOCAL
default y
config FORCE_MAX_ZONEORDER
diff --git a/arch/csky/include/asm/fixmap.h b/arch/csky/include/asm/fixmap.h
index 81f9477d5..4b589cc20 100644
--- a/arch/csky/include/asm/fixmap.h
+++ b/arch/csky/include/asm/fixmap.h
@@ -8,7 +8,7 @@
#include <asm/memory.h>
#ifdef CONFIG_HIGHMEM
#include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
#endif
enum fixed_addresses {
@@ -17,7 +17,7 @@ enum fixed_addresses {
#endif
#ifdef CONFIG_HIGHMEM
FIX_KMAP_BEGIN,
- FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
+ FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
#endif
__end_of_fixed_addresses
};
diff --git a/arch/csky/include/asm/highmem.h b/arch/csky/include/asm/highmem.h
index 14645e3d5..1f4ed3f4c 100644
--- a/arch/csky/include/asm/highmem.h
+++ b/arch/csky/include/asm/highmem.h
@@ -9,7 +9,7 @@
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/uaccess.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
#include <asm/cache.h>
/* undef for production */
@@ -32,10 +32,12 @@ extern pte_t *pkmap_page_table;
#define ARCH_HAS_KMAP_FLUSH_TLB
extern void kmap_flush_tlb(unsigned long addr);
-extern void *kmap_atomic_pfn(unsigned long pfn);
#define flush_cache_kmaps() do {} while (0)
+#define arch_kmap_local_post_map(vaddr, pteval) kmap_flush_tlb(vaddr)
+#define arch_kmap_local_post_unmap(vaddr) kmap_flush_tlb(vaddr)
+
extern void kmap_init(void);
#endif /* __KERNEL__ */
diff --git a/arch/csky/mm/highmem.c b/arch/csky/mm/highmem.c
index 89c10800a..4161df3c6 100644
--- a/arch/csky/mm/highmem.c
+++ b/arch/csky/mm/highmem.c
@@ -9,8 +9,6 @@
#include <asm/tlbflush.h>
#include <asm/cacheflush.h>
-static pte_t *kmap_pte;
-
unsigned long highstart_pfn, highend_pfn;
void kmap_flush_tlb(unsigned long addr)
@@ -19,67 +17,7 @@ void kmap_flush_tlb(unsigned long addr)
}
EXPORT_SYMBOL(kmap_flush_tlb);
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
- unsigned long vaddr;
- int idx, type;
-
- type = kmap_atomic_idx_push();
- idx = type + KM_TYPE_NR*smp_processor_id();
- vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
- BUG_ON(!pte_none(*(kmap_pte - idx)));
-#endif
- set_pte(kmap_pte-idx, mk_pte(page, prot));
- flush_tlb_one((unsigned long)vaddr);
-
- return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
- unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
- int idx;
-
- if (vaddr < FIXADDR_START)
- return;
-
-#ifdef CONFIG_DEBUG_HIGHMEM
- idx = KM_TYPE_NR*smp_processor_id() + kmap_atomic_idx();
-
- BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-
- pte_clear(&init_mm, vaddr, kmap_pte - idx);
- flush_tlb_one(vaddr);
-#else
- (void) idx; /* to kill a warning */
-#endif
- kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
-
-/*
- * This is the same as kmap_atomic() but can map memory that doesn't
- * have a struct page associated with it.
- */
-void *kmap_atomic_pfn(unsigned long pfn)
-{
- unsigned long vaddr;
- int idx, type;
-
- pagefault_disable();
-
- type = kmap_atomic_idx_push();
- idx = type + KM_TYPE_NR*smp_processor_id();
- vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
- set_pte(kmap_pte-idx, pfn_pte(pfn, PAGE_KERNEL));
- flush_tlb_one(vaddr);
-
- return (void *) vaddr;
-}
-
-static void __init kmap_pages_init(void)
+void __init kmap_init(void)
{
unsigned long vaddr;
pgd_t *pgd;
@@ -96,14 +34,3 @@ static void __init kmap_pages_init(void)
pte = pte_offset_kernel(pmd, vaddr);
pkmap_page_table = pte;
}
-
-void __init kmap_init(void)
-{
- unsigned long vaddr;
-
- kmap_pages_init();
-
- vaddr = __fix_to_virt(FIX_KMAP_BEGIN);
-
- kmap_pte = pte_offset_kernel((pmd_t *)pgd_offset_k(vaddr), vaddr);
-}
diff --git a/arch/hexagon/include/asm/spinlock_types.h b/arch/hexagon/include/asm/spinlock_types.h
index 19d233497..de72fb230 100644
--- a/arch/hexagon/include/asm/spinlock_types.h
+++ b/arch/hexagon/include/asm/spinlock_types.h
@@ -8,10 +8,6 @@
#ifndef _ASM_SPINLOCK_TYPES_H
#define _ASM_SPINLOCK_TYPES_H
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
typedef struct {
volatile unsigned int lock;
} arch_spinlock_t;
diff --git a/arch/ia64/include/asm/kmap_types.h b/arch/ia64/include/asm/kmap_types.h
deleted file mode 100644
index 5c268cf7c..000000000
--- a/arch/ia64/include/asm/kmap_types.h
+++ /dev/null
@@ -1,13 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_IA64_KMAP_TYPES_H
-#define _ASM_IA64_KMAP_TYPES_H
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-#define __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif /* _ASM_IA64_KMAP_TYPES_H */
diff --git a/arch/ia64/include/asm/spinlock_types.h b/arch/ia64/include/asm/spinlock_types.h
index 6e345fefc..681408d68 100644
--- a/arch/ia64/include/asm/spinlock_types.h
+++ b/arch/ia64/include/asm/spinlock_types.h
@@ -2,10 +2,6 @@
#ifndef _ASM_IA64_SPINLOCK_TYPES_H
#define _ASM_IA64_SPINLOCK_TYPES_H
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
typedef struct {
volatile unsigned int lock;
} arch_spinlock_t;
diff --git a/arch/ia64/kernel/time.c b/arch/ia64/kernel/time.c
index 7abc5f37b..733e0e332 100644
--- a/arch/ia64/kernel/time.c
+++ b/arch/ia64/kernel/time.c
@@ -138,12 +138,8 @@ void vtime_account_kernel(struct task_struct *tsk)
struct thread_info *ti = task_thread_info(tsk);
__u64 stime = vtime_delta(tsk);
- if ((tsk->flags & PF_VCPU) && !irq_count())
+ if (tsk->flags & PF_VCPU)
ti->gtime += stime;
- else if (hardirq_count())
- ti->hardirq_time += stime;
- else if (in_serving_softirq())
- ti->softirq_time += stime;
else
ti->stime += stime;
}
@@ -156,6 +152,20 @@ void vtime_account_idle(struct task_struct *tsk)
ti->idle_time += vtime_delta(tsk);
}
+void vtime_account_softirq(struct task_struct *tsk)
+{
+ struct thread_info *ti = task_thread_info(tsk);
+
+ ti->softirq_time += vtime_delta(tsk);
+}
+
+void vtime_account_hardirq(struct task_struct *tsk)
+{
+ struct thread_info *ti = task_thread_info(tsk);
+
+ ti->hardirq_time += vtime_delta(tsk);
+}
+
#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
static irqreturn_t
diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
index 33925ffed..7f6ca0ab4 100644
--- a/arch/microblaze/Kconfig
+++ b/arch/microblaze/Kconfig
@@ -155,6 +155,7 @@ config XILINX_UNCACHED_SHADOW
config HIGHMEM
bool "High memory support"
depends on MMU
+ select KMAP_LOCAL
help
The address space of Microblaze processors is only 4 Gigabytes large
and it has to accommodate user address space, kernel address
diff --git a/arch/microblaze/include/asm/fixmap.h b/arch/microblaze/include/asm/fixmap.h
index 0379ce522..e6e9288bf 100644
--- a/arch/microblaze/include/asm/fixmap.h
+++ b/arch/microblaze/include/asm/fixmap.h
@@ -20,7 +20,7 @@
#include <asm/page.h>
#ifdef CONFIG_HIGHMEM
#include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
#endif
#define FIXADDR_TOP ((unsigned long)(-PAGE_SIZE))
@@ -47,7 +47,7 @@ enum fixed_addresses {
FIX_HOLE,
#ifdef CONFIG_HIGHMEM
FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
- FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * num_possible_cpus()) - 1,
+ FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * num_possible_cpus()) - 1,
#endif
__end_of_fixed_addresses
};
diff --git a/arch/microblaze/include/asm/highmem.h b/arch/microblaze/include/asm/highmem.h
index 284ca8fb5..4418633fb 100644
--- a/arch/microblaze/include/asm/highmem.h
+++ b/arch/microblaze/include/asm/highmem.h
@@ -25,7 +25,6 @@
#include <linux/uaccess.h>
#include <asm/fixmap.h>
-extern pte_t *kmap_pte;
extern pte_t *pkmap_page_table;
/*
@@ -52,6 +51,11 @@ extern pte_t *pkmap_page_table;
#define flush_cache_kmaps() { flush_icache(); flush_dcache(); }
+#define arch_kmap_local_post_map(vaddr, pteval) \
+ local_flush_tlb_page(NULL, vaddr);
+#define arch_kmap_local_post_unmap(vaddr) \
+ local_flush_tlb_page(NULL, vaddr);
+
#endif /* __KERNEL__ */
#endif /* _ASM_HIGHMEM_H */
diff --git a/arch/microblaze/mm/Makefile b/arch/microblaze/mm/Makefile
index 1b16875ce..8ced71100 100644
--- a/arch/microblaze/mm/Makefile
+++ b/arch/microblaze/mm/Makefile
@@ -6,4 +6,3 @@
obj-y := consistent.o init.o
obj-$(CONFIG_MMU) += pgtable.o mmu_context.o fault.o
-obj-$(CONFIG_HIGHMEM) += highmem.o
diff --git a/arch/microblaze/mm/highmem.c b/arch/microblaze/mm/highmem.c
deleted file mode 100644
index 92e089041..000000000
--- a/arch/microblaze/mm/highmem.c
+++ /dev/null
@@ -1,78 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * highmem.c: virtual kernel memory mappings for high memory
- *
- * PowerPC version, stolen from the i386 version.
- *
- * Used in CONFIG_HIGHMEM systems for memory pages which
- * are not addressable by direct kernel virtual addresses.
- *
- * Copyright (C) 1999 Gerhard Wichert, Siemens AG
- * Gerhard.Wichert@pdb.siemens.de
- *
- *
- * Redesigned the x86 32-bit VM architecture to deal with
- * up to 16 Terrabyte physical memory. With current x86 CPUs
- * we now support up to 64 Gigabytes physical RAM.
- *
- * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
- *
- * Reworked for PowerPC by various contributors. Moved from
- * highmem.h by Benjamin Herrenschmidt (c) 2009 IBM Corp.
- */
-
-#include <linux/export.h>
-#include <linux/highmem.h>
-
-/*
- * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
- * gives a more generic (and caching) interface. But kmap_atomic can
- * be used in IRQ contexts, so in some (very limited) cases we need
- * it.
- */
-#include <asm/tlbflush.h>
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-
- unsigned long vaddr;
- int idx, type;
-
- type = kmap_atomic_idx_push();
- idx = type + KM_TYPE_NR*smp_processor_id();
- vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
- BUG_ON(!pte_none(*(kmap_pte-idx)));
-#endif
- set_pte_at(&init_mm, vaddr, kmap_pte-idx, mk_pte(page, prot));
- local_flush_tlb_page(NULL, vaddr);
-
- return (void *) vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
- unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
- int type;
- unsigned int idx;
-
- if (vaddr < __fix_to_virt(FIX_KMAP_END))
- return;
-
- type = kmap_atomic_idx();
-
- idx = type + KM_TYPE_NR * smp_processor_id();
-#ifdef CONFIG_DEBUG_HIGHMEM
- BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-#endif
- /*
- * force other mappings to Oops if they'll try to access
- * this pte without first remap it
- */
- pte_clear(&init_mm, vaddr, kmap_pte-idx);
- local_flush_tlb_page(NULL, vaddr);
-
- kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
diff --git a/arch/microblaze/mm/init.c b/arch/microblaze/mm/init.c
index 4a0c30ced..498eaa4d3 100644
--- a/arch/microblaze/mm/init.c
+++ b/arch/microblaze/mm/init.c
@@ -49,17 +49,11 @@ unsigned long lowmem_size;
EXPORT_SYMBOL(min_low_pfn);
EXPORT_SYMBOL(max_low_pfn);
-#ifdef CONFIG_HIGHMEM
-pte_t *kmap_pte;
-EXPORT_SYMBOL(kmap_pte);
-
static void __init highmem_init(void)
{
pr_debug("%x\n", (u32)PKMAP_BASE);
map_page(PKMAP_BASE, 0, 0); /* XXX gross */
pkmap_page_table = virt_to_kpte(PKMAP_BASE);
-
- kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
}
static void highmem_setup(void)
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 0b87c1819..94b679ba0 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -2728,6 +2728,7 @@ config WAR_MIPS34K_MISSED_ITLB
config HIGHMEM
bool "High Memory Support"
depends on 32BIT && CPU_SUPPORTS_HIGHMEM && SYS_SUPPORTS_HIGHMEM && !CPU_MIPS32_3_5_EVA
+ select KMAP_LOCAL
config CPU_SUPPORTS_HIGHMEM
bool
diff --git a/arch/mips/include/asm/fixmap.h b/arch/mips/include/asm/fixmap.h
index 743535be7..beea14761 100644
--- a/arch/mips/include/asm/fixmap.h
+++ b/arch/mips/include/asm/fixmap.h
@@ -17,7 +17,7 @@
#include <spaces.h>
#ifdef CONFIG_HIGHMEM
#include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
#endif
/*
@@ -52,7 +52,7 @@ enum fixed_addresses {
#ifdef CONFIG_HIGHMEM
/* reserved pte's for temporary kernel mappings */
FIX_KMAP_BEGIN = FIX_CMAP_END + 1,
- FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
+ FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
#endif
__end_of_fixed_addresses
};
diff --git a/arch/mips/include/asm/highmem.h b/arch/mips/include/asm/highmem.h
index 9f021cf51..1716181ea 100644
--- a/arch/mips/include/asm/highmem.h
+++ b/arch/mips/include/asm/highmem.h
@@ -24,7 +24,7 @@
#include <linux/interrupt.h>
#include <linux/uaccess.h>
#include <asm/cpu-features.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
/* declarations for highmem.c */
extern unsigned long highstart_pfn, highend_pfn;
@@ -48,11 +48,11 @@ extern pte_t *pkmap_page_table;
#define ARCH_HAS_KMAP_FLUSH_TLB
extern void kmap_flush_tlb(unsigned long addr);
-extern void *kmap_atomic_pfn(unsigned long pfn);
#define flush_cache_kmaps() BUG_ON(cpu_has_dc_aliases)
-extern void kmap_init(void);
+#define arch_kmap_local_post_map(vaddr, pteval) local_flush_tlb_one(vaddr)
+#define arch_kmap_local_post_unmap(vaddr) local_flush_tlb_one(vaddr)
#endif /* __KERNEL__ */
diff --git a/arch/mips/include/asm/kmap_types.h b/arch/mips/include/asm/kmap_types.h
deleted file mode 100644
index 16665dc24..000000000
--- a/arch/mips/include/asm/kmap_types.h
+++ /dev/null
@@ -1,13 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_KMAP_TYPES_H
-#define _ASM_KMAP_TYPES_H
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-#define __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif
diff --git a/arch/mips/kernel/crash_dump.c b/arch/mips/kernel/crash_dump.c
index 01b2bd95b..9aba83e1e 100644
--- a/arch/mips/kernel/crash_dump.c
+++ b/arch/mips/kernel/crash_dump.c
@@ -5,8 +5,6 @@
#include <linux/uaccess.h>
#include <linux/slab.h>
-static void *kdump_buf_page;
-
/**
* copy_oldmem_page - copy one page from "oldmem"
* @pfn: page frame number to be copied
@@ -17,51 +15,25 @@ static void *kdump_buf_page;
* @userbuf: if set, @buf is in user address space, use copy_to_user(),
* otherwise @buf is in kernel address space, use memcpy().
*
- * Copy a page from "oldmem". For this page, there is no pte mapped
+ * Copy a page from "oldmem". For this page, there might be no pte mapped
* in the current kernel.
- *
- * Calling copy_to_user() in atomic context is not desirable. Hence first
- * copying the data to a pre-allocated kernel page and then copying to user
- * space in non-atomic context.
*/
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
- size_t csize, unsigned long offset, int userbuf)
+ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
+ unsigned long offset, int userbuf)
{
void *vaddr;
if (!csize)
return 0;
- vaddr = kmap_atomic_pfn(pfn);
+ vaddr = kmap_local_pfn(pfn);
if (!userbuf) {
- memcpy(buf, (vaddr + offset), csize);
- kunmap_atomic(vaddr);
+ memcpy(buf, vaddr + offset, csize);
} else {
- if (!kdump_buf_page) {
- pr_warn("Kdump: Kdump buffer page not allocated\n");
-
- return -EFAULT;
- }
- copy_page(kdump_buf_page, vaddr);
- kunmap_atomic(vaddr);
- if (copy_to_user(buf, (kdump_buf_page + offset), csize))
- return -EFAULT;
+ if (copy_to_user(buf, vaddr + offset, csize))
+ csize = -EFAULT;
}
return csize;
}
-
-static int __init kdump_buf_page_init(void)
-{
- int ret = 0;
-
- kdump_buf_page = kmalloc(PAGE_SIZE, GFP_KERNEL);
- if (!kdump_buf_page) {
- pr_warn("Kdump: Failed to allocate kdump buffer page\n");
- ret = -ENOMEM;
- }
-
- return ret;
-}
-arch_initcall(kdump_buf_page_init);
diff --git a/arch/mips/mm/highmem.c b/arch/mips/mm/highmem.c
index 5fec7f45d..57e2f08f0 100644
--- a/arch/mips/mm/highmem.c
+++ b/arch/mips/mm/highmem.c
@@ -8,8 +8,6 @@
#include <asm/fixmap.h>
#include <asm/tlbflush.h>
-static pte_t *kmap_pte;
-
unsigned long highstart_pfn, highend_pfn;
void kmap_flush_tlb(unsigned long addr)
@@ -17,78 +15,3 @@ void kmap_flush_tlb(unsigned long addr)
flush_tlb_one(addr);
}
EXPORT_SYMBOL(kmap_flush_tlb);
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
- unsigned long vaddr;
- int idx, type;
-
- type = kmap_atomic_idx_push();
- idx = type + KM_TYPE_NR*smp_processor_id();
- vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
- BUG_ON(!pte_none(*(kmap_pte - idx)));
-#endif
- set_pte(kmap_pte-idx, mk_pte(page, prot));
- local_flush_tlb_one((unsigned long)vaddr);
-
- return (void*) vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
- unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
- int type __maybe_unused;
-
- if (vaddr < FIXADDR_START)
- return;
-
- type = kmap_atomic_idx();
-#ifdef CONFIG_DEBUG_HIGHMEM
- {
- int idx = type + KM_TYPE_NR * smp_processor_id();
-
- BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-
- /*
- * force other mappings to Oops if they'll try to access
- * this pte without first remap it
- */
- pte_clear(&init_mm, vaddr, kmap_pte-idx);
- local_flush_tlb_one(vaddr);
- }
-#endif
- kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
-
-/*
- * This is the same as kmap_atomic() but can map memory that doesn't
- * have a struct page associated with it.
- */
-void *kmap_atomic_pfn(unsigned long pfn)
-{
- unsigned long vaddr;
- int idx, type;
-
- preempt_disable();
- pagefault_disable();
-
- type = kmap_atomic_idx_push();
- idx = type + KM_TYPE_NR*smp_processor_id();
- vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
- set_pte(kmap_pte-idx, pfn_pte(pfn, PAGE_KERNEL));
- flush_tlb_one(vaddr);
-
- return (void*) vaddr;
-}
-
-void __init kmap_init(void)
-{
- unsigned long kmap_vstart;
-
- /* cache the first kmap pte */
- kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
- kmap_pte = virt_to_kpte(kmap_vstart);
-}
diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c
index 32e7b869a..f0fcf36dd 100644
--- a/arch/mips/mm/init.c
+++ b/arch/mips/mm/init.c
@@ -36,7 +36,6 @@
#include <asm/cachectl.h>
#include <asm/cpu.h>
#include <asm/dma.h>
-#include <asm/kmap_types.h>
#include <asm/maar.h>
#include <asm/mmu_context.h>
#include <asm/sections.h>
@@ -402,9 +401,6 @@ void __init paging_init(void)
pagetable_init();
-#ifdef CONFIG_HIGHMEM
- kmap_init();
-#endif
#ifdef CONFIG_ZONE_DMA
max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
#endif
diff --git a/arch/nds32/Kconfig.cpu b/arch/nds32/Kconfig.cpu
index f88a12fdf..c10759952 100644
--- a/arch/nds32/Kconfig.cpu
+++ b/arch/nds32/Kconfig.cpu
@@ -157,6 +157,7 @@ config HW_SUPPORT_UNALIGNMENT_ACCESS
config HIGHMEM
bool "High Memory Support"
depends on MMU && !CPU_CACHE_ALIASING
+ select KMAP_LOCAL
help
The address space of Andes processors is only 4 Gigabytes large
and it has to accommodate user address space, kernel address
diff --git a/arch/nds32/include/asm/fixmap.h b/arch/nds32/include/asm/fixmap.h
index 5a4bf11e5..2fa09a2de 100644
--- a/arch/nds32/include/asm/fixmap.h
+++ b/arch/nds32/include/asm/fixmap.h
@@ -6,7 +6,7 @@
#ifdef CONFIG_HIGHMEM
#include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
#endif
enum fixed_addresses {
@@ -14,7 +14,7 @@ enum fixed_addresses {
FIX_KMAP_RESERVED,
FIX_KMAP_BEGIN,
#ifdef CONFIG_HIGHMEM
- FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS),
+ FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
#endif
FIX_EARLYCON_MEM_BASE,
__end_of_fixed_addresses
diff --git a/arch/nds32/include/asm/highmem.h b/arch/nds32/include/asm/highmem.h
index fe986d0e6..16159a871 100644
--- a/arch/nds32/include/asm/highmem.h
+++ b/arch/nds32/include/asm/highmem.h
@@ -5,7 +5,6 @@
#define _ASM_HIGHMEM_H
#include <asm/proc-fns.h>
-#include <asm/kmap_types.h>
#include <asm/fixmap.h>
/*
@@ -45,11 +44,22 @@ extern pte_t *pkmap_page_table;
extern void kmap_init(void);
/*
- * The following functions are already defined by <linux/highmem.h>
- * when CONFIG_HIGHMEM is not set.
+ * FIXME: The below looks broken vs. a kmap_atomic() in task context which
+ * is interupted and another kmap_atomic() happens in interrupt context.
+ * But what do I know about nds32. -- tglx
*/
-#ifdef CONFIG_HIGHMEM
-extern void *kmap_atomic_pfn(unsigned long pfn);
-#endif
+#define arch_kmap_local_post_map(vaddr, pteval) \
+ do { \
+ __nds32__tlbop_inv(vaddr); \
+ __nds32__mtsr_dsb(vaddr, NDS32_SR_TLB_VPN); \
+ __nds32__tlbop_rwr(pteval); \
+ __nds32__isb(); \
+ } while (0)
+
+#define arch_kmap_local_pre_unmap(vaddr) \
+ do { \
+ __nds32__tlbop_inv(vaddr); \
+ __nds32__isb(); \
+ } while (0)
#endif
diff --git a/arch/nds32/mm/Makefile b/arch/nds32/mm/Makefile
index 897ecaf5c..14fb2e8eb 100644
--- a/arch/nds32/mm/Makefile
+++ b/arch/nds32/mm/Makefile
@@ -3,7 +3,6 @@ obj-y := extable.o tlb.o fault.o init.o mmap.o \
mm-nds32.o cacheflush.o proc.o
obj-$(CONFIG_ALIGNMENT_TRAP) += alignment.o
-obj-$(CONFIG_HIGHMEM) += highmem.o
ifdef CONFIG_FUNCTION_TRACER
CFLAGS_REMOVE_proc.o = $(CC_FLAGS_FTRACE)
diff --git a/arch/nds32/mm/highmem.c b/arch/nds32/mm/highmem.c
deleted file mode 100644
index 4284cd59e..000000000
--- a/arch/nds32/mm/highmem.c
+++ /dev/null
@@ -1,48 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-// Copyright (C) 2005-2017 Andes Technology Corporation
-
-#include <linux/export.h>
-#include <linux/highmem.h>
-#include <linux/sched.h>
-#include <linux/smp.h>
-#include <linux/interrupt.h>
-#include <linux/memblock.h>
-#include <asm/fixmap.h>
-#include <asm/tlbflush.h>
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
- unsigned int idx;
- unsigned long vaddr, pte;
- int type;
- pte_t *ptep;
-
- type = kmap_atomic_idx_push();
-
- idx = type + KM_TYPE_NR * smp_processor_id();
- vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
- pte = (page_to_pfn(page) << PAGE_SHIFT) | prot;
- ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
- set_pte(ptep, pte);
-
- __nds32__tlbop_inv(vaddr);
- __nds32__mtsr_dsb(vaddr, NDS32_SR_TLB_VPN);
- __nds32__tlbop_rwr(pte);
- __nds32__isb();
- return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
- if (kvaddr >= (void *)FIXADDR_START) {
- unsigned long vaddr = (unsigned long)kvaddr;
- pte_t *ptep;
- kmap_atomic_idx_pop();
- __nds32__tlbop_inv(vaddr);
- __nds32__isb();
- ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
- set_pte(ptep, 0);
- }
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
diff --git a/arch/openrisc/mm/init.c b/arch/openrisc/mm/init.c
index 5e88c351e..f3fa02b88 100644
--- a/arch/openrisc/mm/init.c
+++ b/arch/openrisc/mm/init.c
@@ -33,7 +33,6 @@
#include <asm/io.h>
#include <asm/tlb.h>
#include <asm/mmu_context.h>
-#include <asm/kmap_types.h>
#include <asm/fixmap.h>
#include <asm/tlbflush.h>
#include <asm/sections.h>
diff --git a/arch/openrisc/mm/ioremap.c b/arch/openrisc/mm/ioremap.c
index a978590d8..5aed97a18 100644
--- a/arch/openrisc/mm/ioremap.c
+++ b/arch/openrisc/mm/ioremap.c
@@ -15,7 +15,6 @@
#include <linux/io.h>
#include <linux/pgtable.h>
#include <asm/pgalloc.h>
-#include <asm/kmap_types.h>
#include <asm/fixmap.h>
#include <asm/bug.h>
#include <linux/sched.h>
diff --git a/arch/parisc/include/asm/hardirq.h b/arch/parisc/include/asm/hardirq.h
index 7f7039516..fad29aa6f 100644
--- a/arch/parisc/include/asm/hardirq.h
+++ b/arch/parisc/include/asm/hardirq.h
@@ -32,7 +32,6 @@ typedef struct {
DECLARE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
#define __ARCH_IRQ_STAT
-#define __IRQ_STAT(cpu, member) (irq_stat[cpu].member)
#define inc_irq_stat(member) this_cpu_inc(irq_stat.member)
#define __inc_irq_stat(member) __this_cpu_inc(irq_stat.member)
#define ack_bad_irq(irq) WARN(1, "unexpected IRQ trap at vector %02x\n", irq)
diff --git a/arch/parisc/include/asm/kmap_types.h b/arch/parisc/include/asm/kmap_types.h
deleted file mode 100644
index 3e70b5cd1..000000000
--- a/arch/parisc/include/asm/kmap_types.h
+++ /dev/null
@@ -1,13 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_KMAP_TYPES_H
-#define _ASM_KMAP_TYPES_H
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-#define __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index ed06e0c32..a0cf63581 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -146,6 +146,7 @@ config PPC
select ARCH_MIGHT_HAVE_PC_SERIO
select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
select ARCH_SUPPORTS_ATOMIC_RMW
+ select ARCH_SUPPORTS_RT if HAVE_POSIX_CPU_TIMERS_TASK_WORK
select ARCH_USE_BUILTIN_BSWAP
select ARCH_USE_CMPXCHG_LOCKREF if PPC64
select ARCH_USE_QUEUED_RWLOCKS if PPC_QUEUED_SPINLOCKS
@@ -234,6 +235,7 @@ config PPC
select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI && !HAVE_HARDLOCKUP_DETECTOR_ARCH
select HAVE_PERF_REGS
select HAVE_PERF_USER_STACK_DUMP
+ select HAVE_PREEMPT_LAZY
select MMU_GATHER_RCU_TABLE_FREE
select MMU_GATHER_PAGE_SIZE
select HAVE_REGS_AND_STACK_ACCESS_API
@@ -241,6 +243,7 @@ config PPC
select HAVE_SYSCALL_TRACEPOINTS
select HAVE_VIRT_CPU_ACCOUNTING
select HAVE_IRQ_TIME_ACCOUNTING
+ select HAVE_POSIX_CPU_TIMERS_TASK_WORK if !KVM
select HAVE_RSEQ
select IOMMU_HELPER if PPC64
select IRQ_DOMAIN
@@ -414,6 +417,7 @@ menu "Kernel options"
config HIGHMEM
bool "High memory support"
depends on PPC32
+ select KMAP_LOCAL
source "kernel/Kconfig.hz"
diff --git a/arch/powerpc/include/asm/cmpxchg.h b/arch/powerpc/include/asm/cmpxchg.h
index cf091c4c2..7371f7e23 100644
--- a/arch/powerpc/include/asm/cmpxchg.h
+++ b/arch/powerpc/include/asm/cmpxchg.h
@@ -5,7 +5,7 @@
#ifdef __KERNEL__
#include <linux/compiler.h>
#include <asm/synch.h>
-#include <linux/bug.h>
+#include <linux/bits.h>
#ifdef __BIG_ENDIAN
#define BITOFF_CAL(size, off) ((sizeof(u32) - size - off) * BITS_PER_BYTE)
diff --git a/arch/powerpc/include/asm/fixmap.h b/arch/powerpc/include/asm/fixmap.h
index 897cc6875..a832aeafe 100644
--- a/arch/powerpc/include/asm/fixmap.h
+++ b/arch/powerpc/include/asm/fixmap.h
@@ -20,7 +20,7 @@
#include <asm/page.h>
#ifdef CONFIG_HIGHMEM
#include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
#endif
#ifdef CONFIG_PPC64
@@ -61,7 +61,7 @@ enum fixed_addresses {
FIX_EARLY_DEBUG_BASE = FIX_EARLY_DEBUG_TOP+(ALIGN(SZ_128K, PAGE_SIZE)/PAGE_SIZE)-1,
#ifdef CONFIG_HIGHMEM
FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
- FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
+ FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
#endif
#ifdef CONFIG_PPC_8xx
/* For IMMR we need an aligned 512K area */
diff --git a/arch/powerpc/include/asm/highmem.h b/arch/powerpc/include/asm/highmem.h
index 104026f7d..80a5ae771 100644
--- a/arch/powerpc/include/asm/highmem.h
+++ b/arch/powerpc/include/asm/highmem.h
@@ -24,12 +24,10 @@
#ifdef __KERNEL__
#include <linux/interrupt.h>
-#include <asm/kmap_types.h>
#include <asm/cacheflush.h>
#include <asm/page.h>
#include <asm/fixmap.h>
-extern pte_t *kmap_pte;
extern pte_t *pkmap_page_table;
/*
@@ -60,6 +58,11 @@ extern pte_t *pkmap_page_table;
#define flush_cache_kmaps() flush_cache_all()
+#define arch_kmap_local_post_map(vaddr, pteval) \
+ local_flush_tlb_page(NULL, vaddr)
+#define arch_kmap_local_post_unmap(vaddr) \
+ local_flush_tlb_page(NULL, vaddr)
+
#endif /* __KERNEL__ */
#endif /* _ASM_HIGHMEM_H */
diff --git a/arch/powerpc/include/asm/kmap_types.h b/arch/powerpc/include/asm/kmap_types.h
deleted file mode 100644
index c8fa182d4..000000000
--- a/arch/powerpc/include/asm/kmap_types.h
+++ /dev/null
@@ -1,13 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-#ifndef _ASM_POWERPC_KMAP_TYPES_H
-#define _ASM_POWERPC_KMAP_TYPES_H
-
-#ifdef __KERNEL__
-
-/*
- */
-
-#define KM_TYPE_NR 16
-
-#endif /* __KERNEL__ */
-#endif /* _ASM_POWERPC_KMAP_TYPES_H */
diff --git a/arch/powerpc/include/asm/simple_spinlock_types.h b/arch/powerpc/include/asm/simple_spinlock_types.h
index 0f3cdd8fa..d45561e9e 100644
--- a/arch/powerpc/include/asm/simple_spinlock_types.h
+++ b/arch/powerpc/include/asm/simple_spinlock_types.h
@@ -2,7 +2,7 @@
#ifndef _ASM_POWERPC_SIMPLE_SPINLOCK_TYPES_H
#define _ASM_POWERPC_SIMPLE_SPINLOCK_TYPES_H
-#ifndef __LINUX_SPINLOCK_TYPES_H
+#if !defined(__LINUX_SPINLOCK_TYPES_H) && !defined(__LINUX_RT_MUTEX_H)
# error "please don't include this file directly"
#endif
diff --git a/arch/powerpc/include/asm/spinlock_types.h b/arch/powerpc/include/asm/spinlock_types.h
index c5d742f18..cc6922a01 100644
--- a/arch/powerpc/include/asm/spinlock_types.h
+++ b/arch/powerpc/include/asm/spinlock_types.h
@@ -2,10 +2,6 @@
#ifndef _ASM_POWERPC_SPINLOCK_TYPES_H
#define _ASM_POWERPC_SPINLOCK_TYPES_H
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
#ifdef CONFIG_PPC_QUEUED_SPINLOCKS
#include <asm-generic/qspinlock_types.h>
#include <asm-generic/qrwlock_types.h>
diff --git a/arch/powerpc/include/asm/stackprotector.h b/arch/powerpc/include/asm/stackprotector.h
index 1c8460e23..b1653c160 100644
--- a/arch/powerpc/include/asm/stackprotector.h
+++ b/arch/powerpc/include/asm/stackprotector.h
@@ -24,7 +24,11 @@ static __always_inline void boot_init_stack_canary(void)
unsigned long canary;
/* Try to get a semi random initial value. */
+#ifdef CONFIG_PREEMPT_RT
+ canary = (unsigned long)&canary;
+#else
canary = get_random_canary();
+#endif
canary ^= mftb();
canary ^= LINUX_VERSION_CODE;
canary &= CANARY_MASK;
diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h
index f4f4564c6..5b7e9bb9f 100644
--- a/arch/powerpc/include/asm/thread_info.h
+++ b/arch/powerpc/include/asm/thread_info.h
@@ -54,6 +54,8 @@
struct thread_info {
int preempt_count; /* 0 => preemptable,
<0 => BUG */
+ int preempt_lazy_count; /* 0 => preemptable,
+ <0 => BUG */
#ifdef CONFIG_SMP
unsigned int cpu;
#endif
@@ -107,11 +109,12 @@ void arch_setup_new_exec(void);
#define TIF_SINGLESTEP 8 /* singlestepping active */
#define TIF_NOHZ 9 /* in adaptive nohz mode */
#define TIF_SECCOMP 10 /* secure computing */
-#define TIF_RESTOREALL 11 /* Restore all regs (implies NOERROR) */
-#define TIF_NOERROR 12 /* Force successful syscall return */
+
+#define TIF_NEED_RESCHED_LAZY 11 /* lazy rescheduling necessary */
+#define TIF_SYSCALL_TRACEPOINT 12 /* syscall tracepoint instrumentation */
+
#define TIF_NOTIFY_RESUME 13 /* callback before returning to user */
#define TIF_UPROBE 14 /* breakpointed or single-stepping */
-#define TIF_SYSCALL_TRACEPOINT 15 /* syscall tracepoint instrumentation */
#define TIF_EMULATE_STACK_STORE 16 /* Is an instruction emulation
for stack store? */
#define TIF_MEMDIE 17 /* is terminating due to OOM killer */
@@ -120,6 +123,9 @@ void arch_setup_new_exec(void);
#endif
#define TIF_POLLING_NRFLAG 19 /* true if poll_idle() is polling TIF_NEED_RESCHED */
#define TIF_32BIT 20 /* 32 bit binary */
+#define TIF_RESTOREALL 21 /* Restore all regs (implies NOERROR) */
+#define TIF_NOERROR 22 /* Force successful syscall return */
+
/* as above, but as bit values */
#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
@@ -140,6 +146,7 @@ void arch_setup_new_exec(void);
#define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
#define _TIF_EMULATE_STACK_STORE (1<<TIF_EMULATE_STACK_STORE)
#define _TIF_NOHZ (1<<TIF_NOHZ)
+#define _TIF_NEED_RESCHED_LAZY (1<<TIF_NEED_RESCHED_LAZY)
#define _TIF_SYSCALL_EMU (1<<TIF_SYSCALL_EMU)
#define _TIF_SYSCALL_DOTRACE (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
_TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT | \
@@ -147,10 +154,12 @@ void arch_setup_new_exec(void);
#define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
_TIF_NOTIFY_RESUME | _TIF_UPROBE | \
- _TIF_RESTORE_TM | _TIF_PATCH_PENDING | \
+ _TIF_RESTORE_TM | _TIF_PATCH_PENDING | _TIF_NEED_RESCHED_LAZY | \
_TIF_NOTIFY_SIGNAL)
#define _TIF_PERSYSCALL_MASK (_TIF_RESTOREALL|_TIF_NOERROR)
+#define _TIF_NEED_RESCHED_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)
+
/* Bits in local_flags */
/* Don't move TLF_NAPPING without adjusting the code in entry_32.S */
#define TLF_NAPPING 0 /* idle thread enabled NAP mode */
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 760f656ef..0a351a99d 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -187,6 +187,7 @@ int main(void)
OFFSET(TI_FLAGS, thread_info, flags);
OFFSET(TI_LOCAL_FLAGS, thread_info, local_flags);
OFFSET(TI_PREEMPT, thread_info, preempt_count);
+ OFFSET(TI_PREEMPT_LAZY, thread_info, preempt_lazy_count);
#ifdef CONFIG_PPC64
OFFSET(DCACHEL1BLOCKSIZE, ppc64_caches, l1d.block_size);
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 459f5d00b..fc9517a97 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -414,7 +414,9 @@ ret_from_syscall:
mtmsr r10
lwz r9,TI_FLAGS(r2)
li r8,-MAX_ERRNO
- andi. r0,r9,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)
+ lis r0,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)@h
+ ori r0,r0, (_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)@l
+ and. r0,r9,r0
bne- syscall_exit_work
cmplw 0,r3,r8
blt+ syscall_exit_cont
@@ -530,13 +532,13 @@ syscall_dotrace:
b syscall_dotrace_cont
syscall_exit_work:
- andi. r0,r9,_TIF_RESTOREALL
+ andis. r0,r9,_TIF_RESTOREALL@h
beq+ 0f
REST_NVGPRS(r1)
b 2f
0: cmplw 0,r3,r8
blt+ 1f
- andi. r0,r9,_TIF_NOERROR
+ andis. r0,r9,_TIF_NOERROR@h
bne- 1f
lwz r11,_CCR(r1) /* Load CR */
neg r3,r3
@@ -545,12 +547,12 @@ syscall_exit_work:
1: stw r6,RESULT(r1) /* Save result */
stw r3,GPR3(r1) /* Update return value */
-2: andi. r0,r9,(_TIF_PERSYSCALL_MASK)
+2: andis. r0,r9,(_TIF_PERSYSCALL_MASK)@h
beq 4f
/* Clear per-syscall TIF flags if any are set. */
- li r11,_TIF_PERSYSCALL_MASK
+ lis r11,(_TIF_PERSYSCALL_MASK)@h
addi r12,r2,TI_FLAGS
3: lwarx r8,0,r12
andc r8,r8,r11
@@ -927,7 +929,14 @@ resume_kernel:
cmpwi 0,r0,0 /* if non-zero, just restore regs and return */
bne restore_kuap
andi. r8,r8,_TIF_NEED_RESCHED
+ bne+ 1f
+ lwz r0,TI_PREEMPT_LAZY(r2)
+ cmpwi 0,r0,0 /* if non-zero, just restore regs and return */
+ bne restore_kuap
+ lwz r0,TI_FLAGS(r2)
+ andi. r0,r0,_TIF_NEED_RESCHED_LAZY
beq+ restore_kuap
+1:
lwz r3,_MSR(r1)
andi. r0,r3,MSR_EE /* interrupts off? */
beq restore_kuap /* don't schedule if so */
@@ -1248,7 +1257,7 @@ global_dbcr0:
#endif /* !(CONFIG_4xx || CONFIG_BOOKE) */
do_work: /* r10 contains MSR_KERNEL here */
- andi. r0,r9,_TIF_NEED_RESCHED
+ andi. r0,r9,_TIF_NEED_RESCHED_MASK
beq do_user_signal
do_resched: /* r10 contains MSR_KERNEL here */
@@ -1267,7 +1276,7 @@ recheck:
LOAD_REG_IMMEDIATE(r10,MSR_KERNEL)
mtmsr r10 /* disable interrupts */
lwz r9,TI_FLAGS(r2)
- andi. r0,r9,_TIF_NEED_RESCHED
+ andi. r0,r9,_TIF_NEED_RESCHED_MASK
bne- do_resched
andi. r0,r9,_TIF_USER_WORK_MASK
beq restore_user
diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index e91d3ba1e..5ce64cfe6 100644
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S
@@ -1080,7 +1080,7 @@ _GLOBAL(ret_from_except_lite)
li r10, -1
mtspr SPRN_DBSR,r10
b restore
-1: andi. r0,r4,_TIF_NEED_RESCHED
+1: andi. r0,r4,_TIF_NEED_RESCHED_MASK
beq 2f
bl restore_interrupts
SCHEDULE_USER
@@ -1132,12 +1132,20 @@ resume_kernel:
bne- 0b
1:
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
/* Check if we need to preempt */
+ lwz r8,TI_PREEMPT(r9)
+ cmpwi 0,r8,0 /* if non-zero, just restore regs and return */
+ bne restore
andi. r0,r4,_TIF_NEED_RESCHED
+ bne+ check_count
+
+ andi. r0,r4,_TIF_NEED_RESCHED_LAZY
beq+ restore
+ lwz r8,TI_PREEMPT_LAZY(r9)
+
/* Check that preempt_count() == 0 and interrupts are enabled */
- lwz r8,TI_PREEMPT(r9)
+check_count:
cmpwi cr0,r8,0
bne restore
ld r0,SOFTE(r1)
@@ -1158,7 +1166,7 @@ resume_kernel:
* interrupted after loading SRR0/1.
*/
wrteei 0
-#endif /* CONFIG_PREEMPT */
+#endif /* CONFIG_PREEMPTION */
restore:
/*
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index e8a548447..5ad4f27cb 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -753,10 +753,12 @@ void *mcheckirq_ctx[NR_CPUS] __read_mostly;
void *softirq_ctx[NR_CPUS] __read_mostly;
void *hardirq_ctx[NR_CPUS] __read_mostly;
+#ifndef CONFIG_PREEMPT_RT
void do_softirq_own_stack(void)
{
call_do_softirq(softirq_ctx[smp_processor_id()]);
}
+#endif
irq_hw_number_t virq_to_hw(unsigned int virq)
{
diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index 717e658b9..08ee95ad6 100644
--- a/arch/powerpc/kernel/misc_32.S
+++ b/arch/powerpc/kernel/misc_32.S
@@ -31,6 +31,7 @@
* We store the saved ksp_limit in the unused part
* of the STACK_FRAME_OVERHEAD
*/
+#ifndef CONFIG_PREEMPT_RT
_GLOBAL(call_do_softirq)
mflr r0
stw r0,4(r1)
@@ -46,6 +47,7 @@ _GLOBAL(call_do_softirq)
stw r10,THREAD+KSP_LIMIT(r2)
mtlr r0
blr
+#endif
/*
* void call_do_irq(struct pt_regs *regs, void *sp);
diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
index 070465825..a6b33f7b3 100644
--- a/arch/powerpc/kernel/misc_64.S
+++ b/arch/powerpc/kernel/misc_64.S
@@ -27,6 +27,7 @@
.text
+#ifndef CONFIG_PREEMPT_RT
_GLOBAL(call_do_softirq)
mflr r0
std r0,16(r1)
@@ -37,6 +38,7 @@ _GLOBAL(call_do_softirq)
ld r0,16(r1)
mtlr r0
blr
+#endif
_GLOBAL(call_do_irq)
mflr r0
diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c
index 532f22637..1ef55f4b3 100644
--- a/arch/powerpc/kernel/nvram_64.c
+++ b/arch/powerpc/kernel/nvram_64.c
@@ -73,7 +73,8 @@ static const char *nvram_os_partitions[] = {
};
static void oops_to_nvram(struct kmsg_dumper *dumper,
- enum kmsg_dump_reason reason);
+ enum kmsg_dump_reason reason,
+ struct kmsg_dumper_iter *iter);
static struct kmsg_dumper nvram_kmsg_dumper = {
.dump = oops_to_nvram
@@ -643,7 +644,8 @@ void __init nvram_init_oops_partition(int rtas_partition_exists)
* partition. If that's too much, go back and capture uncompressed text.
*/
static void oops_to_nvram(struct kmsg_dumper *dumper,
- enum kmsg_dump_reason reason)
+ enum kmsg_dump_reason reason,
+ struct kmsg_dumper_iter *iter)
{
struct oops_log_info *oops_hdr = (struct oops_log_info *)oops_buf;
static unsigned int oops_count = 0;
@@ -681,13 +683,13 @@ static void oops_to_nvram(struct kmsg_dumper *dumper,
return;
if (big_oops_buf) {
- kmsg_dump_get_buffer(dumper, false,
+ kmsg_dump_get_buffer(iter, false,
big_oops_buf, big_oops_buf_sz, &text_len);
rc = zip_oops(text_len);
}
if (rc != 0) {
- kmsg_dump_rewind(dumper);
- kmsg_dump_get_buffer(dumper, false,
+ kmsg_dump_rewind(iter);
+ kmsg_dump_get_buffer(iter, false,
oops_data, oops_data_sz, &text_len);
err_type = ERR_TYPE_KERNEL_PANIC;
oops_hdr->version = cpu_to_be16(OOPS_HDR_VERSION);
diff --git a/arch/powerpc/kernel/syscall_64.c b/arch/powerpc/kernel/syscall_64.c
index 310bcd768..ae3212dcf 100644
--- a/arch/powerpc/kernel/syscall_64.c
+++ b/arch/powerpc/kernel/syscall_64.c
@@ -193,7 +193,7 @@ again:
ti_flags = READ_ONCE(*ti_flagsp);
while (unlikely(ti_flags & (_TIF_USER_WORK_MASK & ~_TIF_RESTORE_TM))) {
local_irq_enable();
- if (ti_flags & _TIF_NEED_RESCHED) {
+ if (ti_flags & _TIF_NEED_RESCHED_MASK) {
schedule();
} else {
/*
@@ -277,7 +277,7 @@ again:
ti_flags = READ_ONCE(*ti_flagsp);
while (unlikely(ti_flags & (_TIF_USER_WORK_MASK & ~_TIF_RESTORE_TM))) {
local_irq_enable(); /* returning to user: may enable */
- if (ti_flags & _TIF_NEED_RESCHED) {
+ if (ti_flags & _TIF_NEED_RESCHED_MASK) {
schedule();
} else {
if (ti_flags & _TIF_SIGPENDING)
@@ -361,11 +361,15 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs, unsign
/* Returning to a kernel context with local irqs enabled. */
WARN_ON_ONCE(!(regs->msr & MSR_EE));
again:
- if (IS_ENABLED(CONFIG_PREEMPT)) {
+ if (IS_ENABLED(CONFIG_PREEMPTION)) {
/* Return to preemptible kernel context */
if (unlikely(*ti_flagsp & _TIF_NEED_RESCHED)) {
if (preempt_count() == 0)
preempt_schedule_irq();
+ } else if (unlikely(*ti_flagsp & _TIF_NEED_RESCHED_LAZY)) {
+ if ((preempt_count() == 0) &&
+ (current_thread_info()->preempt_lazy_count == 0))
+ preempt_schedule_irq();
}
}
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index ba9b54d35..588e081ca 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -312,12 +312,11 @@ static unsigned long vtime_delta_scaled(struct cpu_accounting_data *acct,
return stime_scaled;
}
-static unsigned long vtime_delta(struct task_struct *tsk,
+static unsigned long vtime_delta(struct cpu_accounting_data *acct,
unsigned long *stime_scaled,
unsigned long *steal_time)
{
unsigned long now, stime;
- struct cpu_accounting_data *acct = get_accounting(tsk);
WARN_ON_ONCE(!irqs_disabled());
@@ -332,29 +331,30 @@ static unsigned long vtime_delta(struct task_struct *tsk,
return stime;
}
+static void vtime_delta_kernel(struct cpu_accounting_data *acct,
+ unsigned long *stime, unsigned long *stime_scaled)
+{
+ unsigned long steal_time;
+
+ *stime = vtime_delta(acct, stime_scaled, &steal_time);
+ *stime -= min(*stime, steal_time);
+ acct->steal_time += steal_time;
+}
+
void vtime_account_kernel(struct task_struct *tsk)
{
- unsigned long stime, stime_scaled, steal_time;
struct cpu_accounting_data *acct = get_accounting(tsk);
+ unsigned long stime, stime_scaled;
- stime = vtime_delta(tsk, &stime_scaled, &steal_time);
-
- stime -= min(stime, steal_time);
- acct->steal_time += steal_time;
+ vtime_delta_kernel(acct, &stime, &stime_scaled);
- if ((tsk->flags & PF_VCPU) && !irq_count()) {
+ if (tsk->flags & PF_VCPU) {
acct->gtime += stime;
#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
acct->utime_scaled += stime_scaled;
#endif
} else {
- if (hardirq_count())
- acct->hardirq_time += stime;
- else if (in_serving_softirq())
- acct->softirq_time += stime;
- else
- acct->stime += stime;
-
+ acct->stime += stime;
#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
acct->stime_scaled += stime_scaled;
#endif
@@ -367,10 +367,34 @@ void vtime_account_idle(struct task_struct *tsk)
unsigned long stime, stime_scaled, steal_time;
struct cpu_accounting_data *acct = get_accounting(tsk);
- stime = vtime_delta(tsk, &stime_scaled, &steal_time);
+ stime = vtime_delta(acct, &stime_scaled, &steal_time);
acct->idle_time += stime + steal_time;
}
+static void vtime_account_irq_field(struct cpu_accounting_data *acct,
+ unsigned long *field)
+{
+ unsigned long stime, stime_scaled;
+
+ vtime_delta_kernel(acct, &stime, &stime_scaled);
+ *field += stime;
+#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
+ acct->stime_scaled += stime_scaled;
+#endif
+}
+
+void vtime_account_softirq(struct task_struct *tsk)
+{
+ struct cpu_accounting_data *acct = get_accounting(tsk);
+ vtime_account_irq_field(acct, &acct->softirq_time);
+}
+
+void vtime_account_hardirq(struct task_struct *tsk)
+{
+ struct cpu_accounting_data *acct = get_accounting(tsk);
+ vtime_account_irq_field(acct, &acct->hardirq_time);
+}
+
static void vtime_flush_scaled(struct task_struct *tsk,
struct cpu_accounting_data *acct)
{
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 43d1a1e0f..b4973058e 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -173,7 +173,6 @@ extern void panic_flush_kmsg_start(void)
extern void panic_flush_kmsg_end(void)
{
- printk_safe_flush_on_panic();
kmsg_dump(KMSG_DUMP_PANIC);
bust_spinlocks(0);
debug_locks_off();
@@ -263,12 +262,17 @@ static char *get_mmu_str(void)
static int __die(const char *str, struct pt_regs *regs, long err)
{
+ const char *pr = "";
+
printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
+ if (IS_ENABLED(CONFIG_PREEMPTION))
+ pr = IS_ENABLED(CONFIG_PREEMPT_RT) ? " PREEMPT_RT" : " PREEMPT";
+
printk("%s PAGE_SIZE=%luK%s%s%s%s%s%s %s\n",
IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN) ? "LE" : "BE",
PAGE_SIZE / 1024, get_mmu_str(),
- IS_ENABLED(CONFIG_PREEMPT) ? " PREEMPT" : "",
+ pr,
IS_ENABLED(CONFIG_SMP) ? " SMP" : "",
IS_ENABLED(CONFIG_SMP) ? (" NR_CPUS=" __stringify(NR_CPUS)) : "",
debug_pagealloc_enabled() ? " DEBUG_PAGEALLOC" : "",
diff --git a/arch/powerpc/kernel/watchdog.c b/arch/powerpc/kernel/watchdog.c
index 75b2a6c4d..db40e20d0 100644
--- a/arch/powerpc/kernel/watchdog.c
+++ b/arch/powerpc/kernel/watchdog.c
@@ -185,11 +185,6 @@ static void watchdog_smp_panic(int cpu, u64 tb)
wd_smp_unlock(&flags);
- printk_safe_flush();
- /*
- * printk_safe_flush() seems to require another print
- * before anything actually goes out to console.
- */
if (sysctl_hardlockup_all_cpu_backtrace)
trigger_allbutself_cpu_backtrace();
diff --git a/arch/powerpc/kexec/crash.c b/arch/powerpc/kexec/crash.c
index c9a889880..d488311ef 100644
--- a/arch/powerpc/kexec/crash.c
+++ b/arch/powerpc/kexec/crash.c
@@ -311,9 +311,6 @@ void default_machine_crash_shutdown(struct pt_regs *regs)
unsigned int i;
int (*old_handler)(struct pt_regs *regs);
- /* Avoid hardlocking with irresponsive CPU holding logbuf_lock */
- printk_nmi_enter();
-
/*
* This function is only called after the system
* has panicked or is otherwise in a critical state.
diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig
index 549591d9a..efb5bfe93 100644
--- a/arch/powerpc/kvm/Kconfig
+++ b/arch/powerpc/kvm/Kconfig
@@ -178,6 +178,7 @@ config KVM_E500MC
config KVM_MPIC
bool "KVM in-kernel MPIC emulation"
depends on KVM && E500
+ depends on !PREEMPT_RT
select HAVE_KVM_IRQCHIP
select HAVE_KVM_IRQFD
select HAVE_KVM_IRQ_ROUTING
diff --git a/arch/powerpc/mm/Makefile b/arch/powerpc/mm/Makefile
index 55b4a8bd4..3b4e9e4e2 100644
--- a/arch/powerpc/mm/Makefile
+++ b/arch/powerpc/mm/Makefile
@@ -16,7 +16,6 @@ obj-$(CONFIG_NEED_MULTIPLE_NODES) += numa.o
obj-$(CONFIG_PPC_MM_SLICES) += slice.o
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
obj-$(CONFIG_NOT_COHERENT_CACHE) += dma-noncoherent.o
-obj-$(CONFIG_HIGHMEM) += highmem.o
obj-$(CONFIG_PPC_COPRO_BASE) += copro_fault.o
obj-$(CONFIG_PPC_PTDUMP) += ptdump/
obj-$(CONFIG_KASAN) += kasan/
diff --git a/arch/powerpc/mm/highmem.c b/arch/powerpc/mm/highmem.c
deleted file mode 100644
index 624b4438a..000000000
--- a/arch/powerpc/mm/highmem.c
+++ /dev/null
@@ -1,67 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * highmem.c: virtual kernel memory mappings for high memory
- *
- * PowerPC version, stolen from the i386 version.
- *
- * Used in CONFIG_HIGHMEM systems for memory pages which
- * are not addressable by direct kernel virtual addresses.
- *
- * Copyright (C) 1999 Gerhard Wichert, Siemens AG
- * Gerhard.Wichert@pdb.siemens.de
- *
- *
- * Redesigned the x86 32-bit VM architecture to deal with
- * up to 16 Terrabyte physical memory. With current x86 CPUs
- * we now support up to 64 Gigabytes physical RAM.
- *
- * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
- *
- * Reworked for PowerPC by various contributors. Moved from
- * highmem.h by Benjamin Herrenschmidt (c) 2009 IBM Corp.
- */
-
-#include <linux/highmem.h>
-#include <linux/module.h>
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
- unsigned long vaddr;
- int idx, type;
-
- type = kmap_atomic_idx_push();
- idx = type + KM_TYPE_NR*smp_processor_id();
- vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
- WARN_ON(IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !pte_none(*(kmap_pte - idx)));
- __set_pte_at(&init_mm, vaddr, kmap_pte-idx, mk_pte(page, prot), 1);
- local_flush_tlb_page(NULL, vaddr);
-
- return (void*) vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
- unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-
- if (vaddr < __fix_to_virt(FIX_KMAP_END))
- return;
-
- if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM)) {
- int type = kmap_atomic_idx();
- unsigned int idx;
-
- idx = type + KM_TYPE_NR * smp_processor_id();
- WARN_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-
- /*
- * force other mappings to Oops if they'll try to access
- * this pte without first remap it
- */
- pte_clear(&init_mm, vaddr, kmap_pte-idx);
- local_flush_tlb_page(NULL, vaddr);
- }
-
- kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 08e3422eb..1faa07898 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -63,11 +63,6 @@
unsigned long long memory_limit;
bool init_mem_is_free;
-#ifdef CONFIG_HIGHMEM
-pte_t *kmap_pte;
-EXPORT_SYMBOL(kmap_pte);
-#endif
-
pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
unsigned long size, pgprot_t vma_prot)
{
@@ -237,8 +232,6 @@ void __init paging_init(void)
map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */
pkmap_page_table = virt_to_kpte(PKMAP_BASE);
-
- kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
#endif /* CONFIG_HIGHMEM */
printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
diff --git a/arch/powerpc/platforms/powernv/opal-kmsg.c b/arch/powerpc/platforms/powernv/opal-kmsg.c
index 6c3bc4b4d..ec862846b 100644
--- a/arch/powerpc/platforms/powernv/opal-kmsg.c
+++ b/arch/powerpc/platforms/powernv/opal-kmsg.c
@@ -20,7 +20,8 @@
* message, it just ensures that OPAL completely flushes the console buffer.
*/
static void kmsg_dump_opal_console_flush(struct kmsg_dumper *dumper,
- enum kmsg_dump_reason reason)
+ enum kmsg_dump_reason reason,
+ struct kmsg_dumper_iter *iter)
{
/*
* Outside of a panic context the pollers will continue to run,
diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index 245f1f8df..f05555dde 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -24,6 +24,7 @@
#include <linux/of.h>
#include <linux/iommu.h>
#include <linux/rculist.h>
+#include <linux/local_lock.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/rtas.h>
@@ -190,7 +191,13 @@ static int tce_build_pSeriesLP(unsigned long liobn, long tcenum, long tceshift,
return ret;
}
-static DEFINE_PER_CPU(__be64 *, tce_page);
+struct tce_page {
+ __be64 * page;
+ local_lock_t lock;
+};
+static DEFINE_PER_CPU(struct tce_page, tce_page) = {
+ .lock = INIT_LOCAL_LOCK(lock),
+};
static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
long npages, unsigned long uaddr,
@@ -212,9 +219,10 @@ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
direction, attrs);
}
- local_irq_save(flags); /* to protect tcep and the page behind it */
+ /* to protect tcep and the page behind it */
+ local_lock_irqsave(&tce_page.lock, flags);
- tcep = __this_cpu_read(tce_page);
+ tcep = __this_cpu_read(tce_page.page);
/* This is safe to do since interrupts are off when we're called
* from iommu_alloc{,_sg}()
@@ -223,12 +231,12 @@ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
tcep = (__be64 *)__get_free_page(GFP_ATOMIC);
/* If allocation fails, fall back to the loop implementation */
if (!tcep) {
- local_irq_restore(flags);
+ local_unlock_irqrestore(&tce_page.lock, flags);
return tce_build_pSeriesLP(tbl->it_index, tcenum,
tbl->it_page_shift,
npages, uaddr, direction, attrs);
}
- __this_cpu_write(tce_page, tcep);
+ __this_cpu_write(tce_page.page, tcep);
}
rpn = __pa(uaddr) >> TCE_SHIFT;
@@ -258,7 +266,7 @@ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
tcenum += limit;
} while (npages > 0 && !rc);
- local_irq_restore(flags);
+ local_unlock_irqrestore(&tce_page.lock, flags);
if (unlikely(rc == H_NOT_ENOUGH_RESOURCES)) {
ret = (int)rc;
@@ -429,16 +437,17 @@ static int tce_setrange_multi_pSeriesLP(unsigned long start_pfn,
DMA_BIDIRECTIONAL, 0);
}
- local_irq_disable(); /* to protect tcep and the page behind it */
- tcep = __this_cpu_read(tce_page);
+ /* to protect tcep and the page behind it */
+ local_lock_irq(&tce_page.lock);
+ tcep = __this_cpu_read(tce_page.page);
if (!tcep) {
tcep = (__be64 *)__get_free_page(GFP_ATOMIC);
if (!tcep) {
- local_irq_enable();
+ local_unlock_irq(&tce_page.lock);
return -ENOMEM;
}
- __this_cpu_write(tce_page, tcep);
+ __this_cpu_write(tce_page.page, tcep);
}
proto_tce = TCE_PCI_READ | TCE_PCI_WRITE;
@@ -481,7 +490,7 @@ static int tce_setrange_multi_pSeriesLP(unsigned long start_pfn,
/* error cleanup: caller will clear whole range */
- local_irq_enable();
+ local_unlock_irq(&tce_page.lock);
return rc;
}
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index 3de2adc0a..2eef587bf 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -3003,7 +3003,7 @@ print_address(unsigned long addr)
static void
dump_log_buf(void)
{
- struct kmsg_dumper dumper = { .active = 1 };
+ struct kmsg_dumper_iter iter = { .active = 1 };
unsigned char buf[128];
size_t len;
@@ -3015,9 +3015,9 @@ dump_log_buf(void)
catch_memory_errors = 1;
sync();
- kmsg_dump_rewind_nolock(&dumper);
+ kmsg_dump_rewind(&iter);
xmon_start_pagination();
- while (kmsg_dump_get_line_nolock(&dumper, false, buf, sizeof(buf), &len)) {
+ while (kmsg_dump_get_line(&iter, false, buf, sizeof(buf), &len)) {
buf[len] = '\0';
printf("%s", buf);
}
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 7461318e1..517cbf603 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -183,6 +183,7 @@ config S390
select HAVE_RSEQ
select HAVE_SYSCALL_TRACEPOINTS
select HAVE_VIRT_CPU_ACCOUNTING
+ select HAVE_VIRT_CPU_ACCOUNTING_IDLE
select IOMMU_HELPER if PCI
select IOMMU_SUPPORT if PCI
select MODULES_USE_ELF_RELA
diff --git a/arch/s390/include/asm/spinlock_types.h b/arch/s390/include/asm/spinlock_types.h
index cfed272e4..8e28e8176 100644
--- a/arch/s390/include/asm/spinlock_types.h
+++ b/arch/s390/include/asm/spinlock_types.h
@@ -2,10 +2,6 @@
#ifndef __ASM_SPINLOCK_TYPES_H
#define __ASM_SPINLOCK_TYPES_H
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
typedef struct {
int lock;
} __attribute__ ((aligned (4))) arch_spinlock_t;
diff --git a/arch/s390/include/asm/vtime.h b/arch/s390/include/asm/vtime.h
index 3622d4ebc..fac6a6798 100644
--- a/arch/s390/include/asm/vtime.h
+++ b/arch/s390/include/asm/vtime.h
@@ -2,7 +2,6 @@
#ifndef _S390_VTIME_H
#define _S390_VTIME_H
-#define __ARCH_HAS_VTIME_ACCOUNT
#define __ARCH_HAS_VTIME_TASK_SWITCH
#endif /* _S390_VTIME_H */
diff --git a/arch/s390/kernel/vtime.c b/arch/s390/kernel/vtime.c
index 579ec3a8c..9b3c5978b 100644
--- a/arch/s390/kernel/vtime.c
+++ b/arch/s390/kernel/vtime.c
@@ -223,35 +223,50 @@ void vtime_flush(struct task_struct *tsk)
S390_lowcore.avg_steal_timer = avg_steal;
}
+static u64 vtime_delta(void)
+{
+ u64 timer = S390_lowcore.last_update_timer;
+
+ S390_lowcore.last_update_timer = get_vtimer();
+
+ return timer - S390_lowcore.last_update_timer;
+}
+
/*
* Update process times based on virtual cpu times stored by entry.S
* to the lowcore fields user_timer, system_timer & steal_clock.
*/
-void vtime_account_irq_enter(struct task_struct *tsk)
+void vtime_account_kernel(struct task_struct *tsk)
{
- u64 timer;
-
- timer = S390_lowcore.last_update_timer;
- S390_lowcore.last_update_timer = get_vtimer();
- timer -= S390_lowcore.last_update_timer;
+ u64 delta = vtime_delta();
- if ((tsk->flags & PF_VCPU) && (irq_count() == 0))
- S390_lowcore.guest_timer += timer;
- else if (hardirq_count())
- S390_lowcore.hardirq_timer += timer;
- else if (in_serving_softirq())
- S390_lowcore.softirq_timer += timer;
+ if (tsk->flags & PF_VCPU)
+ S390_lowcore.guest_timer += delta;
else
- S390_lowcore.system_timer += timer;
+ S390_lowcore.system_timer += delta;
- virt_timer_forward(timer);
+ virt_timer_forward(delta);
}
-EXPORT_SYMBOL_GPL(vtime_account_irq_enter);
-
-void vtime_account_kernel(struct task_struct *tsk)
-__attribute__((alias("vtime_account_irq_enter")));
EXPORT_SYMBOL_GPL(vtime_account_kernel);
+void vtime_account_softirq(struct task_struct *tsk)
+{
+ u64 delta = vtime_delta();
+
+ S390_lowcore.softirq_timer += delta;
+
+ virt_timer_forward(delta);
+}
+
+void vtime_account_hardirq(struct task_struct *tsk)
+{
+ u64 delta = vtime_delta();
+
+ S390_lowcore.hardirq_timer += delta;
+
+ virt_timer_forward(delta);
+}
+
/*
* Sorted add to a list. List is linear searched until first bigger
* element is found.
diff --git a/arch/sh/include/asm/fixmap.h b/arch/sh/include/asm/fixmap.h
index f38adc189..b07fbc7f7 100644
--- a/arch/sh/include/asm/fixmap.h
+++ b/arch/sh/include/asm/fixmap.h
@@ -13,9 +13,6 @@
#include <linux/kernel.h>
#include <linux/threads.h>
#include <asm/page.h>
-#ifdef CONFIG_HIGHMEM
-#include <asm/kmap_types.h>
-#endif
/*
* Here we define all the compile-time 'special' virtual
@@ -53,11 +50,6 @@ enum fixed_addresses {
FIX_CMAP_BEGIN,
FIX_CMAP_END = FIX_CMAP_BEGIN + (FIX_N_COLOURS * NR_CPUS) - 1,
-#ifdef CONFIG_HIGHMEM
- FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
- FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
-#endif
-
#ifdef CONFIG_IOREMAP_FIXED
/*
* FIX_IOREMAP entries are useful for mapping physical address
diff --git a/arch/sh/include/asm/hardirq.h b/arch/sh/include/asm/hardirq.h
index edaea3559..9fe4495a8 100644
--- a/arch/sh/include/asm/hardirq.h
+++ b/arch/sh/include/asm/hardirq.h
@@ -2,16 +2,10 @@
#ifndef __ASM_SH_HARDIRQ_H
#define __ASM_SH_HARDIRQ_H
-#include <linux/threads.h>
-#include <linux/irq.h>
-
-typedef struct {
- unsigned int __softirq_pending;
- unsigned int __nmi_count; /* arch dependent */
-} ____cacheline_aligned irq_cpustat_t;
-
-#include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
-
extern void ack_bad_irq(unsigned int irq);
+#define ack_bad_irq ack_bad_irq
+#define ARCH_WANTS_NMI_IRQSTAT
+
+#include <asm-generic/hardirq.h>
#endif /* __ASM_SH_HARDIRQ_H */
diff --git a/arch/sh/include/asm/kmap_types.h b/arch/sh/include/asm/kmap_types.h
deleted file mode 100644
index b78107f92..000000000
--- a/arch/sh/include/asm/kmap_types.h
+++ /dev/null
@@ -1,15 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __SH_KMAP_TYPES_H
-#define __SH_KMAP_TYPES_H
-
-/* Dummy header just to define km_type. */
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-#define __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif
diff --git a/arch/sh/include/asm/spinlock_types.h b/arch/sh/include/asm/spinlock_types.h
index e82369f28..22ca9a98b 100644
--- a/arch/sh/include/asm/spinlock_types.h
+++ b/arch/sh/include/asm/spinlock_types.h
@@ -2,10 +2,6 @@
#ifndef __ASM_SH_SPINLOCK_TYPES_H
#define __ASM_SH_SPINLOCK_TYPES_H
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
typedef struct {
volatile unsigned int lock;
} arch_spinlock_t;
diff --git a/arch/sh/kernel/irq.c b/arch/sh/kernel/irq.c
index 5717c7cbd..5db7af565 100644
--- a/arch/sh/kernel/irq.c
+++ b/arch/sh/kernel/irq.c
@@ -44,7 +44,7 @@ int arch_show_interrupts(struct seq_file *p, int prec)
seq_printf(p, "%*s: ", prec, "NMI");
for_each_online_cpu(j)
- seq_printf(p, "%10u ", nmi_count(j));
+ seq_printf(p, "%10u ", per_cpu(irq_stat.__nmi_count, j));
seq_printf(p, " Non-maskable interrupts\n");
seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
@@ -148,6 +148,7 @@ void irq_ctx_exit(int cpu)
hardirq_ctx[cpu] = NULL;
}
+#ifndef CONFIG_PREEMPT_RT
void do_softirq_own_stack(void)
{
struct thread_info *curctx;
@@ -175,6 +176,7 @@ void do_softirq_own_stack(void)
"r5", "r6", "r7", "r8", "r9", "r15", "t", "pr"
);
}
+#endif
#else
static inline void handle_one_irq(unsigned int irq)
{
diff --git a/arch/sh/kernel/traps.c b/arch/sh/kernel/traps.c
index 9c3d32b80..f5beecdac 100644
--- a/arch/sh/kernel/traps.c
+++ b/arch/sh/kernel/traps.c
@@ -186,7 +186,7 @@ BUILD_TRAP_HANDLER(nmi)
arch_ftrace_nmi_enter();
nmi_enter();
- nmi_count(cpu)++;
+ this_cpu_inc(irq_stat.__nmi_count);
switch (notify_die(DIE_NMI, "NMI", regs, 0, vec & 0xff, SIGINT)) {
case NOTIFY_OK:
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index 3348e0c4d..0db6919af 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -362,9 +362,6 @@ void __init mem_init(void)
mem_init_print_info(NULL);
pr_info("virtual kernel memory layout:\n"
" fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n"
-#ifdef CONFIG_HIGHMEM
- " pkmap : 0x%08lx - 0x%08lx (%4ld kB)\n"
-#endif
" vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n"
" lowmem : 0x%08lx - 0x%08lx (%4ld MB) (cached)\n"
#ifdef CONFIG_UNCACHED_MAPPING
@@ -376,11 +373,6 @@ void __init mem_init(void)
FIXADDR_START, FIXADDR_TOP,
(FIXADDR_TOP - FIXADDR_START) >> 10,
-#ifdef CONFIG_HIGHMEM
- PKMAP_BASE, PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
- (LAST_PKMAP*PAGE_SIZE) >> 10,
-#endif
-
(unsigned long)VMALLOC_START, VMALLOC_END,
(VMALLOC_END - VMALLOC_START) >> 20,
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 7e2ce4c8d..1a6e4b187 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -140,6 +140,7 @@ config MMU
config HIGHMEM
bool
default y if SPARC32
+ select KMAP_LOCAL
config ZONE_DMA
bool
diff --git a/arch/sparc/include/asm/highmem.h b/arch/sparc/include/asm/highmem.h
index 6c35f0d27..875116209 100644
--- a/arch/sparc/include/asm/highmem.h
+++ b/arch/sparc/include/asm/highmem.h
@@ -24,7 +24,6 @@
#include <linux/interrupt.h>
#include <linux/pgtable.h>
#include <asm/vaddrs.h>
-#include <asm/kmap_types.h>
#include <asm/pgtsrmmu.h>
/* declarations for highmem.c */
@@ -33,8 +32,6 @@ extern unsigned long highstart_pfn, highend_pfn;
#define kmap_prot __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE)
extern pte_t *pkmap_page_table;
-void kmap_init(void) __init;
-
/*
* Right now we initialize only a single pte table. It can be extended
* easily, subsequent pte tables have to be allocated in one physical
@@ -53,6 +50,11 @@ void kmap_init(void) __init;
#define flush_cache_kmaps() flush_cache_all()
+/* FIXME: Use __flush_tlb_one(vaddr) instead of flush_cache_all() -- Anton */
+#define arch_kmap_local_post_map(vaddr, pteval) flush_cache_all()
+#define arch_kmap_local_post_unmap(vaddr) flush_cache_all()
+
+
#endif /* __KERNEL__ */
#endif /* _ASM_HIGHMEM_H */
diff --git a/arch/sparc/include/asm/kmap_types.h b/arch/sparc/include/asm/kmap_types.h
deleted file mode 100644
index 55a99b6bd..000000000
--- a/arch/sparc/include/asm/kmap_types.h
+++ /dev/null
@@ -1,11 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_KMAP_TYPES_H
-#define _ASM_KMAP_TYPES_H
-
-/* Dummy header just to define km_type. None of this
- * is actually used on sparc. -DaveM
- */
-
-#include <asm-generic/kmap_types.h>
-
-#endif
diff --git a/arch/sparc/include/asm/vaddrs.h b/arch/sparc/include/asm/vaddrs.h
index 84d054b07..4fec0341e 100644
--- a/arch/sparc/include/asm/vaddrs.h
+++ b/arch/sparc/include/asm/vaddrs.h
@@ -32,13 +32,13 @@
#define SRMMU_NOCACHE_ALCRATIO 64 /* 256 pages per 64MB of system RAM */
#ifndef __ASSEMBLY__
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
enum fixed_addresses {
FIX_HOLE,
#ifdef CONFIG_HIGHMEM
FIX_KMAP_BEGIN,
- FIX_KMAP_END = (KM_TYPE_NR * NR_CPUS),
+ FIX_KMAP_END = (KM_MAX_IDX * NR_CPUS),
#endif
__end_of_fixed_addresses
};
diff --git a/arch/sparc/kernel/irq_64.c b/arch/sparc/kernel/irq_64.c
index 3ec9f1402..eb21682ab 100644
--- a/arch/sparc/kernel/irq_64.c
+++ b/arch/sparc/kernel/irq_64.c
@@ -854,6 +854,7 @@ void __irq_entry handler_irq(int pil, struct pt_regs *regs)
set_irq_regs(old_regs);
}
+#ifndef CONFIG_PREEMPT_RT
void do_softirq_own_stack(void)
{
void *orig_sp, *sp = softirq_stack[smp_processor_id()];
@@ -868,6 +869,7 @@ void do_softirq_own_stack(void)
__asm__ __volatile__("mov %0, %%sp"
: : "r" (orig_sp));
}
+#endif
#ifdef CONFIG_HOTPLUG_CPU
void fixup_irqs(void)
diff --git a/arch/sparc/mm/Makefile b/arch/sparc/mm/Makefile
index b078205b7..68db1f859 100644
--- a/arch/sparc/mm/Makefile
+++ b/arch/sparc/mm/Makefile
@@ -15,6 +15,3 @@ obj-$(CONFIG_SPARC32) += leon_mm.o
# Only used by sparc64
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
-
-# Only used by sparc32
-obj-$(CONFIG_HIGHMEM) += highmem.o
diff --git a/arch/sparc/mm/highmem.c b/arch/sparc/mm/highmem.c
deleted file mode 100644
index 8f2a2afb0..000000000
--- a/arch/sparc/mm/highmem.c
+++ /dev/null
@@ -1,115 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * highmem.c: virtual kernel memory mappings for high memory
- *
- * Provides kernel-static versions of atomic kmap functions originally
- * found as inlines in include/asm-sparc/highmem.h. These became
- * needed as kmap_atomic() and kunmap_atomic() started getting
- * called from within modules.
- * -- Tomas Szepe <szepe@pinerecords.com>, September 2002
- *
- * But kmap_atomic() and kunmap_atomic() cannot be inlined in
- * modules because they are loaded with btfixup-ped functions.
- */
-
-/*
- * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
- * gives a more generic (and caching) interface. But kmap_atomic can
- * be used in IRQ contexts, so in some (very limited) cases we need it.
- *
- * XXX This is an old text. Actually, it's good to use atomic kmaps,
- * provided you remember that they are atomic and not try to sleep
- * with a kmap taken, much like a spinlock. Non-atomic kmaps are
- * shared by CPUs, and so precious, and establishing them requires IPI.
- * Atomic kmaps are lightweight and we may have NCPUS more of them.
- */
-#include <linux/highmem.h>
-#include <linux/export.h>
-#include <linux/mm.h>
-
-#include <asm/cacheflush.h>
-#include <asm/tlbflush.h>
-#include <asm/vaddrs.h>
-
-static pte_t *kmap_pte;
-
-void __init kmap_init(void)
-{
- unsigned long address = __fix_to_virt(FIX_KMAP_BEGIN);
-
- /* cache the first kmap pte */
- kmap_pte = virt_to_kpte(address);
-}
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
- unsigned long vaddr;
- long idx, type;
-
- type = kmap_atomic_idx_push();
- idx = type + KM_TYPE_NR*smp_processor_id();
- vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-
-/* XXX Fix - Anton */
-#if 0
- __flush_cache_one(vaddr);
-#else
- flush_cache_all();
-#endif
-
-#ifdef CONFIG_DEBUG_HIGHMEM
- BUG_ON(!pte_none(*(kmap_pte-idx)));
-#endif
- set_pte(kmap_pte-idx, mk_pte(page, prot));
-/* XXX Fix - Anton */
-#if 0
- __flush_tlb_one(vaddr);
-#else
- flush_tlb_all();
-#endif
-
- return (void*) vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
- unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
- int type;
-
- if (vaddr < FIXADDR_START)
- return;
-
- type = kmap_atomic_idx();
-
-#ifdef CONFIG_DEBUG_HIGHMEM
- {
- unsigned long idx;
-
- idx = type + KM_TYPE_NR * smp_processor_id();
- BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN+idx));
-
- /* XXX Fix - Anton */
-#if 0
- __flush_cache_one(vaddr);
-#else
- flush_cache_all();
-#endif
-
- /*
- * force other mappings to Oops if they'll try to access
- * this pte without first remap it
- */
- pte_clear(&init_mm, vaddr, kmap_pte-idx);
- /* XXX Fix - Anton */
-#if 0
- __flush_tlb_one(vaddr);
-#else
- flush_tlb_all();
-#endif
- }
-#endif
-
- kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
diff --git a/arch/sparc/mm/srmmu.c b/arch/sparc/mm/srmmu.c
index 0070f8b9a..a03caa5f6 100644
--- a/arch/sparc/mm/srmmu.c
+++ b/arch/sparc/mm/srmmu.c
@@ -971,8 +971,6 @@ void __init srmmu_paging_init(void)
sparc_context_init(num_contexts);
- kmap_init();
-
{
unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
diff --git a/arch/um/include/asm/fixmap.h b/arch/um/include/asm/fixmap.h
index 2c697a145..2efac5827 100644
--- a/arch/um/include/asm/fixmap.h
+++ b/arch/um/include/asm/fixmap.h
@@ -3,7 +3,6 @@
#define __UM_FIXMAP_H
#include <asm/processor.h>
-#include <asm/kmap_types.h>
#include <asm/archparam.h>
#include <asm/page.h>
#include <linux/threads.h>
diff --git a/arch/um/include/asm/hardirq.h b/arch/um/include/asm/hardirq.h
index b426796d2..52e2c3626 100644
--- a/arch/um/include/asm/hardirq.h
+++ b/arch/um/include/asm/hardirq.h
@@ -2,22 +2,7 @@
#ifndef __ASM_UM_HARDIRQ_H
#define __ASM_UM_HARDIRQ_H
-#include <linux/cache.h>
-#include <linux/threads.h>
-
-typedef struct {
- unsigned int __softirq_pending;
-} ____cacheline_aligned irq_cpustat_t;
-
-#include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
-#include <linux/irq.h>
-
-#ifndef ack_bad_irq
-static inline void ack_bad_irq(unsigned int irq)
-{
- printk(KERN_CRIT "unexpected IRQ trap at vector %02x\n", irq);
-}
-#endif
+#include <asm-generic/hardirq.h>
#define __ARCH_IRQ_EXIT_IRQS_DISABLED 1
diff --git a/arch/um/include/asm/kmap_types.h b/arch/um/include/asm/kmap_types.h
deleted file mode 100644
index b0bd12de1..000000000
--- a/arch/um/include/asm/kmap_types.h
+++ /dev/null
@@ -1,13 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
- */
-
-#ifndef __UM_KMAP_TYPES_H
-#define __UM_KMAP_TYPES_H
-
-/* No more #include "asm/arch/kmap_types.h" ! */
-
-#define KM_TYPE_NR 14
-
-#endif
diff --git a/arch/um/kernel/kmsg_dump.c b/arch/um/kernel/kmsg_dump.c
index e4abac6c9..173999422 100644
--- a/arch/um/kernel/kmsg_dump.c
+++ b/arch/um/kernel/kmsg_dump.c
@@ -1,15 +1,19 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/kmsg_dump.h>
+#include <linux/spinlock.h>
#include <linux/console.h>
#include <shared/init.h>
#include <shared/kern.h>
#include <os.h>
static void kmsg_dumper_stdout(struct kmsg_dumper *dumper,
- enum kmsg_dump_reason reason)
+ enum kmsg_dump_reason reason,
+ struct kmsg_dumper_iter *iter)
{
+ static DEFINE_SPINLOCK(lock);
static char line[1024];
struct console *con;
+ unsigned long flags;
size_t len = 0;
/* only dump kmsg when no console is available */
@@ -24,11 +28,16 @@ static void kmsg_dumper_stdout(struct kmsg_dumper *dumper,
if (con)
return;
+ if (!spin_trylock_irqsave(&lock, flags))
+ return;
+
printf("kmsg_dump:\n");
- while (kmsg_dump_get_line(dumper, true, line, sizeof(line), &len)) {
+ while (kmsg_dump_get_line(iter, true, line, sizeof(line), &len)) {
line[len] = '\0';
printf("%s", line);
}
+
+ spin_unlock_irqrestore(&lock, flags);
}
static struct kmsg_dumper kmsg_dumper = {
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 8ec8cdf83..4ef6aa311 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -16,6 +16,7 @@ config X86_32
select CLKSRC_I8253
select CLONE_BACKWARDS
select HAVE_DEBUG_STACKOVERFLOW
+ select KMAP_LOCAL
select MODULES_USE_ELF_REL
select OLD_SIGACTION
select GENERIC_VDSO_32
@@ -96,6 +97,7 @@ config X86
select ARCH_SUPPORTS_ACPI
select ARCH_SUPPORTS_ATOMIC_RMW
select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
+ select ARCH_SUPPORTS_RT
select ARCH_USE_BUILTIN_BSWAP
select ARCH_USE_QUEUED_RWLOCKS
select ARCH_USE_QUEUED_SPINLOCKS
@@ -220,6 +222,7 @@ config X86
select HAVE_PCI
select HAVE_PERF_REGS
select HAVE_PERF_USER_STACK_DUMP
+ select HAVE_PREEMPT_LAZY
select MMU_GATHER_RCU_TABLE_FREE if PARAVIRT
select HAVE_POSIX_CPU_TIMERS_TASK_WORK
select HAVE_REGS_AND_STACK_ACCESS_API
diff --git a/arch/x86/crypto/aesni-intel_glue.c b/arch/x86/crypto/aesni-intel_glue.c
index be891fdf8..29c716ed1 100644
--- a/arch/x86/crypto/aesni-intel_glue.c
+++ b/arch/x86/crypto/aesni-intel_glue.c
@@ -379,14 +379,14 @@ static int ecb_encrypt(struct skcipher_request *req)
err = skcipher_walk_virt(&walk, req, true);
- kernel_fpu_begin();
while ((nbytes = walk.nbytes)) {
+ kernel_fpu_begin();
aesni_ecb_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr,
nbytes & AES_BLOCK_MASK);
+ kernel_fpu_end();
nbytes &= AES_BLOCK_SIZE - 1;
err = skcipher_walk_done(&walk, nbytes);
}
- kernel_fpu_end();
return err;
}
@@ -401,14 +401,14 @@ static int ecb_decrypt(struct skcipher_request *req)
err = skcipher_walk_virt(&walk, req, true);
- kernel_fpu_begin();
while ((nbytes = walk.nbytes)) {
+ kernel_fpu_begin();
aesni_ecb_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr,
nbytes & AES_BLOCK_MASK);
+ kernel_fpu_end();
nbytes &= AES_BLOCK_SIZE - 1;
err = skcipher_walk_done(&walk, nbytes);
}
- kernel_fpu_end();
return err;
}
@@ -423,14 +423,14 @@ static int cbc_encrypt(struct skcipher_request *req)
err = skcipher_walk_virt(&walk, req, true);
- kernel_fpu_begin();
while ((nbytes = walk.nbytes)) {
+ kernel_fpu_begin();
aesni_cbc_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr,
nbytes & AES_BLOCK_MASK, walk.iv);
+ kernel_fpu_end();
nbytes &= AES_BLOCK_SIZE - 1;
err = skcipher_walk_done(&walk, nbytes);
}
- kernel_fpu_end();
return err;
}
@@ -445,14 +445,14 @@ static int cbc_decrypt(struct skcipher_request *req)
err = skcipher_walk_virt(&walk, req, true);
- kernel_fpu_begin();
while ((nbytes = walk.nbytes)) {
+ kernel_fpu_begin();
aesni_cbc_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr,
nbytes & AES_BLOCK_MASK, walk.iv);
+ kernel_fpu_end();
nbytes &= AES_BLOCK_SIZE - 1;
err = skcipher_walk_done(&walk, nbytes);
}
- kernel_fpu_end();
return err;
}
@@ -500,18 +500,20 @@ static int ctr_crypt(struct skcipher_request *req)
err = skcipher_walk_virt(&walk, req, true);
- kernel_fpu_begin();
while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) {
+ kernel_fpu_begin();
aesni_ctr_enc_tfm(ctx, walk.dst.virt.addr, walk.src.virt.addr,
nbytes & AES_BLOCK_MASK, walk.iv);
+ kernel_fpu_end();
nbytes &= AES_BLOCK_SIZE - 1;
err = skcipher_walk_done(&walk, nbytes);
}
if (walk.nbytes) {
+ kernel_fpu_begin();
ctr_crypt_final(ctx, &walk);
+ kernel_fpu_end();
err = skcipher_walk_done(&walk, 0);
}
- kernel_fpu_end();
return err;
}
diff --git a/arch/x86/crypto/cast5_avx_glue.c b/arch/x86/crypto/cast5_avx_glue.c
index 384ccb00f..2f8df8ef8 100644
--- a/arch/x86/crypto/cast5_avx_glue.c
+++ b/arch/x86/crypto/cast5_avx_glue.c
@@ -46,7 +46,7 @@ static inline void cast5_fpu_end(bool fpu_enabled)
static int ecb_crypt(struct skcipher_request *req, bool enc)
{
- bool fpu_enabled = false;
+ bool fpu_enabled;
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct cast5_ctx *ctx = crypto_skcipher_ctx(tfm);
struct skcipher_walk walk;
@@ -61,7 +61,7 @@ static int ecb_crypt(struct skcipher_request *req, bool enc)
u8 *wsrc = walk.src.virt.addr;
u8 *wdst = walk.dst.virt.addr;
- fpu_enabled = cast5_fpu_begin(fpu_enabled, &walk, nbytes);
+ fpu_enabled = cast5_fpu_begin(false, &walk, nbytes);
/* Process multi-block batch */
if (nbytes >= bsize * CAST5_PARALLEL_BLOCKS) {
@@ -90,10 +90,9 @@ static int ecb_crypt(struct skcipher_request *req, bool enc)
} while (nbytes >= bsize);
done:
+ cast5_fpu_end(fpu_enabled);
err = skcipher_walk_done(&walk, nbytes);
}
-
- cast5_fpu_end(fpu_enabled);
return err;
}
@@ -197,7 +196,7 @@ static int cbc_decrypt(struct skcipher_request *req)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct cast5_ctx *ctx = crypto_skcipher_ctx(tfm);
- bool fpu_enabled = false;
+ bool fpu_enabled;
struct skcipher_walk walk;
unsigned int nbytes;
int err;
@@ -205,12 +204,11 @@ static int cbc_decrypt(struct skcipher_request *req)
err = skcipher_walk_virt(&walk, req, false);
while ((nbytes = walk.nbytes)) {
- fpu_enabled = cast5_fpu_begin(fpu_enabled, &walk, nbytes);
+ fpu_enabled = cast5_fpu_begin(false, &walk, nbytes);
nbytes = __cbc_decrypt(ctx, &walk);
+ cast5_fpu_end(fpu_enabled);
err = skcipher_walk_done(&walk, nbytes);
}
-
- cast5_fpu_end(fpu_enabled);
return err;
}
@@ -277,7 +275,7 @@ static int ctr_crypt(struct skcipher_request *req)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct cast5_ctx *ctx = crypto_skcipher_ctx(tfm);
- bool fpu_enabled = false;
+ bool fpu_enabled;
struct skcipher_walk walk;
unsigned int nbytes;
int err;
@@ -285,13 +283,12 @@ static int ctr_crypt(struct skcipher_request *req)
err = skcipher_walk_virt(&walk, req, false);
while ((nbytes = walk.nbytes) >= CAST5_BLOCK_SIZE) {
- fpu_enabled = cast5_fpu_begin(fpu_enabled, &walk, nbytes);
+ fpu_enabled = cast5_fpu_begin(false, &walk, nbytes);
nbytes = __ctr_crypt(&walk, ctx);
+ cast5_fpu_end(fpu_enabled);
err = skcipher_walk_done(&walk, nbytes);
}
- cast5_fpu_end(fpu_enabled);
-
if (walk.nbytes) {
ctr_crypt_final(&walk, ctx);
err = skcipher_walk_done(&walk, 0);
diff --git a/arch/x86/crypto/glue_helper.c b/arch/x86/crypto/glue_helper.c
index d3d91a0ab..6d0774721 100644
--- a/arch/x86/crypto/glue_helper.c
+++ b/arch/x86/crypto/glue_helper.c
@@ -24,7 +24,7 @@ int glue_ecb_req_128bit(const struct common_glue_ctx *gctx,
void *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req));
const unsigned int bsize = 128 / 8;
struct skcipher_walk walk;
- bool fpu_enabled = false;
+ bool fpu_enabled;
unsigned int nbytes;
int err;
@@ -37,7 +37,7 @@ int glue_ecb_req_128bit(const struct common_glue_ctx *gctx,
unsigned int i;
fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
- &walk, fpu_enabled, nbytes);
+ &walk, false, nbytes);
for (i = 0; i < gctx->num_funcs; i++) {
func_bytes = bsize * gctx->funcs[i].num_blocks;
@@ -55,10 +55,9 @@ int glue_ecb_req_128bit(const struct common_glue_ctx *gctx,
if (nbytes < bsize)
break;
}
+ glue_fpu_end(fpu_enabled);
err = skcipher_walk_done(&walk, nbytes);
}
-
- glue_fpu_end(fpu_enabled);
return err;
}
EXPORT_SYMBOL_GPL(glue_ecb_req_128bit);
@@ -101,7 +100,7 @@ int glue_cbc_decrypt_req_128bit(const struct common_glue_ctx *gctx,
void *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req));
const unsigned int bsize = 128 / 8;
struct skcipher_walk walk;
- bool fpu_enabled = false;
+ bool fpu_enabled;
unsigned int nbytes;
int err;
@@ -115,7 +114,7 @@ int glue_cbc_decrypt_req_128bit(const struct common_glue_ctx *gctx,
u128 last_iv;
fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
- &walk, fpu_enabled, nbytes);
+ &walk, false, nbytes);
/* Start of the last block. */
src += nbytes / bsize - 1;
dst += nbytes / bsize - 1;
@@ -148,10 +147,10 @@ int glue_cbc_decrypt_req_128bit(const struct common_glue_ctx *gctx,
done:
u128_xor(dst, dst, (u128 *)walk.iv);
*(u128 *)walk.iv = last_iv;
+ glue_fpu_end(fpu_enabled);
err = skcipher_walk_done(&walk, nbytes);
}
- glue_fpu_end(fpu_enabled);
return err;
}
EXPORT_SYMBOL_GPL(glue_cbc_decrypt_req_128bit);
@@ -162,7 +161,7 @@ int glue_ctr_req_128bit(const struct common_glue_ctx *gctx,
void *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req));
const unsigned int bsize = 128 / 8;
struct skcipher_walk walk;
- bool fpu_enabled = false;
+ bool fpu_enabled;
unsigned int nbytes;
int err;
@@ -176,7 +175,7 @@ int glue_ctr_req_128bit(const struct common_glue_ctx *gctx,
le128 ctrblk;
fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
- &walk, fpu_enabled, nbytes);
+ &walk, false, nbytes);
be128_to_le128(&ctrblk, (be128 *)walk.iv);
@@ -202,11 +201,10 @@ int glue_ctr_req_128bit(const struct common_glue_ctx *gctx,
}
le128_to_be128((be128 *)walk.iv, &ctrblk);
+ glue_fpu_end(fpu_enabled);
err = skcipher_walk_done(&walk, nbytes);
}
- glue_fpu_end(fpu_enabled);
-
if (nbytes) {
le128 ctrblk;
u128 tmp;
@@ -306,8 +304,14 @@ int glue_xts_req_128bit(const struct common_glue_ctx *gctx,
tweak_fn(tweak_ctx, walk.iv, walk.iv);
while (nbytes) {
+ fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
+ &walk, fpu_enabled,
+ nbytes < bsize ? bsize : nbytes);
nbytes = __glue_xts_req_128bit(gctx, crypt_ctx, &walk);
+ glue_fpu_end(fpu_enabled);
+ fpu_enabled = false;
+
err = skcipher_walk_done(&walk, nbytes);
nbytes = walk.nbytes;
}
diff --git a/arch/x86/include/asm/fixmap.h b/arch/x86/include/asm/fixmap.h
index 77217bd29..8eba66a33 100644
--- a/arch/x86/include/asm/fixmap.h
+++ b/arch/x86/include/asm/fixmap.h
@@ -31,7 +31,7 @@
#include <asm/pgtable_types.h>
#ifdef CONFIG_X86_32
#include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
#else
#include <uapi/asm/vsyscall.h>
#endif
@@ -94,7 +94,7 @@ enum fixed_addresses {
#endif
#ifdef CONFIG_X86_32
FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
- FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
+ FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
#ifdef CONFIG_PCI_MMCONFIG
FIX_PCIE_MCFG,
#endif
@@ -151,7 +151,6 @@ extern void reserve_top_address(unsigned long reserve);
extern int fixmaps_set;
-extern pte_t *kmap_pte;
extern pte_t *pkmap_page_table;
void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
diff --git a/arch/x86/include/asm/fpu/api.h b/arch/x86/include/asm/fpu/api.h
index e34d4b508..4b049abe2 100644
--- a/arch/x86/include/asm/fpu/api.h
+++ b/arch/x86/include/asm/fpu/api.h
@@ -30,6 +30,7 @@ extern void kernel_fpu_begin_mask(unsigned int kfpu_mask);
extern void kernel_fpu_end(void);
extern bool irq_fpu_usable(void);
extern void fpregs_mark_activate(void);
+extern void kernel_fpu_resched(void);
/* Code that is unaware of kernel_fpu_begin_mask() can use this */
static inline void kernel_fpu_begin(void)
@@ -42,17 +43,32 @@ static inline void kernel_fpu_begin(void)
* A context switch will (and softirq might) save CPU's FPU registers to
* fpu->fpstate.regs and set TIF_NEED_FPU_LOAD leaving CPU's FPU registers in
* a random state.
+ *
+ * local_bh_disable() protects against both preemption and soft interrupts
+ * on !RT kernels.
+ *
+ * On RT kernels local_bh_disable() is not sufficient because it only
+ * serializes soft interrupt related sections via a local lock, but stays
+ * preemptible. Disabling preemption is the right choice here as bottom
+ * half processing is always in thread context on RT kernels so it
+ * implicitly prevents bottom half processing as well.
+ *
+ * Disabling preemption also serializes against kernel_fpu_begin().
*/
static inline void fpregs_lock(void)
{
- preempt_disable();
- local_bh_disable();
+ if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+ local_bh_disable();
+ else
+ preempt_disable();
}
static inline void fpregs_unlock(void)
{
- local_bh_enable();
- preempt_enable();
+ if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+ local_bh_enable();
+ else
+ preempt_enable();
}
#ifdef CONFIG_X86_DEBUG_FPU
diff --git a/arch/x86/include/asm/highmem.h b/arch/x86/include/asm/highmem.h
index 0f420b24e..032e02085 100644
--- a/arch/x86/include/asm/highmem.h
+++ b/arch/x86/include/asm/highmem.h
@@ -23,7 +23,6 @@
#include <linux/interrupt.h>
#include <linux/threads.h>
-#include <asm/kmap_types.h>
#include <asm/tlbflush.h>
#include <asm/paravirt.h>
#include <asm/fixmap.h>
@@ -58,11 +57,17 @@ extern unsigned long highstart_pfn, highend_pfn;
#define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT)
#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
-void *kmap_atomic_pfn(unsigned long pfn);
-void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot);
-
#define flush_cache_kmaps() do { } while (0)
+#define arch_kmap_local_post_map(vaddr, pteval) \
+ arch_flush_lazy_mmu_mode()
+
+#define arch_kmap_local_post_unmap(vaddr) \
+ do { \
+ flush_tlb_one_kernel((vaddr)); \
+ arch_flush_lazy_mmu_mode(); \
+ } while (0)
+
extern void add_highpages_with_active_regions(int nid, unsigned long start_pfn,
unsigned long end_pfn);
diff --git a/arch/x86/include/asm/iomap.h b/arch/x86/include/asm/iomap.h
index bacf68c4d..e2de092fc 100644
--- a/arch/x86/include/asm/iomap.h
+++ b/arch/x86/include/asm/iomap.h
@@ -9,19 +9,14 @@
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/uaccess.h>
+#include <linux/highmem.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
-void __iomem *
-iomap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot);
+void __iomem *__iomap_local_pfn_prot(unsigned long pfn, pgprot_t prot);
-void
-iounmap_atomic(void __iomem *kvaddr);
+int iomap_create_wc(resource_size_t base, unsigned long size, pgprot_t *prot);
-int
-iomap_create_wc(resource_size_t base, unsigned long size, pgprot_t *prot);
-
-void
-iomap_free(resource_size_t base, unsigned long size);
+void iomap_free(resource_size_t base, unsigned long size);
#endif /* _ASM_X86_IOMAP_H */
diff --git a/arch/x86/include/asm/kmap_types.h b/arch/x86/include/asm/kmap_types.h
deleted file mode 100644
index 04ab8266e..000000000
--- a/arch/x86/include/asm/kmap_types.h
+++ /dev/null
@@ -1,13 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_X86_KMAP_TYPES_H
-#define _ASM_X86_KMAP_TYPES_H
-
-#if defined(CONFIG_X86_32) && defined(CONFIG_DEBUG_HIGHMEM)
-#define __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif /* _ASM_X86_KMAP_TYPES_H */
diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index b30b56d47..9632218bf 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -43,7 +43,6 @@
#ifndef __ASSEMBLY__
#include <asm/desc_defs.h>
-#include <asm/kmap_types.h>
#include <asm/pgtable_types.h>
#include <asm/nospec-branch.h>
diff --git a/arch/x86/include/asm/preempt.h b/arch/x86/include/asm/preempt.h
index 2380df419..a3b73de27 100644
--- a/arch/x86/include/asm/preempt.h
+++ b/arch/x86/include/asm/preempt.h
@@ -90,21 +90,54 @@ static __always_inline void __preempt_count_sub(int val)
* a decrement which hits zero means we have no preempt_count and should
* reschedule.
*/
-static __always_inline bool __preempt_count_dec_and_test(void)
+static __always_inline bool ____preempt_count_dec_and_test(void)
{
return GEN_UNARY_RMWcc("decl", __preempt_count, e, __percpu_arg([var]));
}
+static __always_inline bool __preempt_count_dec_and_test(void)
+{
+ if (____preempt_count_dec_and_test())
+ return true;
+#ifdef CONFIG_PREEMPT_LAZY
+ if (preempt_count())
+ return false;
+ if (current_thread_info()->preempt_lazy_count)
+ return false;
+ return test_thread_flag(TIF_NEED_RESCHED_LAZY);
+#else
+ return false;
+#endif
+}
+
/*
* Returns true when we need to resched and can (barring IRQ state).
*/
static __always_inline bool should_resched(int preempt_offset)
{
+#ifdef CONFIG_PREEMPT_LAZY
+ u32 tmp;
+ tmp = raw_cpu_read_4(__preempt_count);
+ if (tmp == preempt_offset)
+ return true;
+
+ /* preempt count == 0 ? */
+ tmp &= ~PREEMPT_NEED_RESCHED;
+ if (tmp != preempt_offset)
+ return false;
+ /* XXX PREEMPT_LOCK_OFFSET */
+ if (current_thread_info()->preempt_lazy_count)
+ return false;
+ return test_thread_flag(TIF_NEED_RESCHED_LAZY);
+#else
return unlikely(raw_cpu_read_4(__preempt_count) == preempt_offset);
+#endif
}
#ifdef CONFIG_PREEMPTION
-
+#ifdef CONFIG_PREEMPT_RT
+ extern void preempt_schedule_lock(void);
+#endif
extern asmlinkage void preempt_schedule(void);
extern asmlinkage void preempt_schedule_thunk(void);
diff --git a/arch/x86/include/asm/signal.h b/arch/x86/include/asm/signal.h
index 6fd8410a3..f3bf2f515 100644
--- a/arch/x86/include/asm/signal.h
+++ b/arch/x86/include/asm/signal.h
@@ -28,6 +28,19 @@ typedef struct {
#define SA_IA32_ABI 0x02000000u
#define SA_X32_ABI 0x01000000u
+/*
+ * Because some traps use the IST stack, we must keep preemption
+ * disabled while calling do_trap(), but do_trap() may call
+ * force_sig_info() which will grab the signal spin_locks for the
+ * task, which in PREEMPT_RT are mutexes. By defining
+ * ARCH_RT_DELAYS_SIGNAL_SEND the force_sig_info() will set
+ * TIF_NOTIFY_RESUME and set up the signal to be sent on exit of the
+ * trap.
+ */
+#if defined(CONFIG_PREEMPT_RT)
+#define ARCH_RT_DELAYS_SIGNAL_SEND
+#endif
+
#ifndef CONFIG_COMPAT
typedef sigset_t compat_sigset_t;
#endif
diff --git a/arch/x86/include/asm/stackprotector.h b/arch/x86/include/asm/stackprotector.h
index b6ffe58c7..e79e75ede 100644
--- a/arch/x86/include/asm/stackprotector.h
+++ b/arch/x86/include/asm/stackprotector.h
@@ -50,7 +50,7 @@
*/
static __always_inline void boot_init_stack_canary(void)
{
- u64 canary;
+ u64 canary = 0;
u64 tsc;
#ifdef CONFIG_X86_64
@@ -61,8 +61,14 @@ static __always_inline void boot_init_stack_canary(void)
* of randomness. The TSC only matters for very early init,
* there it already has some randomness on most systems. Later
* on during the bootup the random pool has true entropy too.
+ * For preempt-rt we need to weaken the randomness a bit, as
+ * we can't call into the random generator from atomic context
+ * due to locking constraints. We just leave canary
+ * uninitialized and use the TSC based randomness on top of it.
*/
+#ifndef CONFIG_PREEMPT_RT
get_random_bytes(&canary, sizeof(canary));
+#endif
tsc = rdtsc();
canary += tsc + (tsc << 32UL);
canary &= CANARY_MASK;
diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index 2b3c98069..c67e0be1e 100644
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -60,6 +60,8 @@ struct thread_info {
#ifdef CONFIG_SMP
u32 cpu; /* current CPU */
#endif
+ int preempt_lazy_count; /* 0 => lazy preemptable
+ <0 => BUG */
KABI_RESERVE(1)
KABI_RESERVE(2)
};
@@ -67,12 +69,17 @@ struct thread_info {
#define INIT_THREAD_INFO(tsk) \
{ \
.flags = 0, \
+ .preempt_lazy_count = 0, \
}
#else /* !__ASSEMBLY__ */
#include <asm/asm-offsets.h>
+#define GET_THREAD_INFO(reg) \
+ _ASM_MOV PER_CPU_VAR(cpu_current_top_of_stack),reg ; \
+ _ASM_SUB $(THREAD_SIZE),reg ;
+
#endif
/*
@@ -109,6 +116,7 @@ struct thread_info {
#define TIF_SYSCALL_TRACEPOINT 28 /* syscall tracepoint instrumentation */
#define TIF_ADDR32 29 /* 32-bit address space on 64 bits */
#define TIF_X32 30 /* 32-bit native x86-64 binary */
+#define TIF_NEED_RESCHED_LAZY 31 /* lazy rescheduling necessary */
#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
@@ -130,6 +138,7 @@ struct thread_info {
#define _TIF_IA32 (1 << TIF_IA32)
#define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL)
#define _TIF_SLD (1 << TIF_SLD)
+#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY)
#define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG)
#define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP)
#define _TIF_FORCED_TF (1 << TIF_FORCED_TF)
@@ -162,6 +171,8 @@ struct thread_info {
#define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW)
+#define _TIF_NEED_RESCHED_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)
+
#define STACK_WARN (THREAD_SIZE/8)
/*
diff --git a/arch/x86/kernel/crash_dump_32.c b/arch/x86/kernel/crash_dump_32.c
index 33ee47670..5fcac46aa 100644
--- a/arch/x86/kernel/crash_dump_32.c
+++ b/arch/x86/kernel/crash_dump_32.c
@@ -13,8 +13,6 @@
#include <linux/uaccess.h>
-static void *kdump_buf_page;
-
static inline bool is_crashed_pfn_valid(unsigned long pfn)
{
#ifndef CONFIG_X86_PAE
@@ -41,15 +39,11 @@ static inline bool is_crashed_pfn_valid(unsigned long pfn)
* @userbuf: if set, @buf is in user address space, use copy_to_user(),
* otherwise @buf is in kernel address space, use memcpy().
*
- * Copy a page from "oldmem". For this page, there is no pte mapped
- * in the current kernel. We stitch up a pte, similar to kmap_atomic.
- *
- * Calling copy_to_user() in atomic context is not desirable. Hence first
- * copying the data to a pre-allocated kernel page and then copying to user
- * space in non-atomic context.
+ * Copy a page from "oldmem". For this page, there might be no pte mapped
+ * in the current kernel.
*/
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
- size_t csize, unsigned long offset, int userbuf)
+ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
+ unsigned long offset, int userbuf)
{
void *vaddr;
@@ -59,38 +53,16 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
if (!is_crashed_pfn_valid(pfn))
return -EFAULT;
- vaddr = kmap_atomic_pfn(pfn);
+ vaddr = kmap_local_pfn(pfn);
if (!userbuf) {
- memcpy(buf, (vaddr + offset), csize);
- kunmap_atomic(vaddr);
+ memcpy(buf, vaddr + offset, csize);
} else {
- if (!kdump_buf_page) {
- printk(KERN_WARNING "Kdump: Kdump buffer page not"
- " allocated\n");
- kunmap_atomic(vaddr);
- return -EFAULT;
- }
- copy_page(kdump_buf_page, vaddr);
- kunmap_atomic(vaddr);
- if (copy_to_user(buf, (kdump_buf_page + offset), csize))
- return -EFAULT;
+ if (copy_to_user(buf, vaddr + offset, csize))
+ csize = -EFAULT;
}
- return csize;
-}
+ kunmap_local(vaddr);
-static int __init kdump_buf_page_init(void)
-{
- int ret = 0;
-
- kdump_buf_page = kmalloc(PAGE_SIZE, GFP_KERNEL);
- if (!kdump_buf_page) {
- printk(KERN_WARNING "Kdump: Failed to allocate kdump buffer"
- " page\n");
- ret = -ENOMEM;
- }
-
- return ret;
+ return csize;
}
-arch_initcall(kdump_buf_page_init);
diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index 49a56bac0..0ae1b836a 100644
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -82,6 +82,18 @@ bool irq_fpu_usable(void)
}
EXPORT_SYMBOL(irq_fpu_usable);
+void kernel_fpu_resched(void)
+{
+ WARN_ON_FPU(!this_cpu_read(in_kernel_fpu));
+
+ if (should_resched(PREEMPT_OFFSET)) {
+ kernel_fpu_end();
+ cond_resched();
+ kernel_fpu_begin();
+ }
+}
+EXPORT_SYMBOL_GPL(kernel_fpu_resched);
+
/*
* Save the FPU register state in fpu->fpstate->regs. The register state is
* preserved.
diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c
index 0b79efc87..93c6b88b3 100644
--- a/arch/x86/kernel/irq_32.c
+++ b/arch/x86/kernel/irq_32.c
@@ -131,6 +131,7 @@ int irq_init_percpu_irqstack(unsigned int cpu)
return 0;
}
+#ifndef CONFIG_PREEMPT_RT
void do_softirq_own_stack(void)
{
struct irq_stack *irqstk;
@@ -147,6 +148,7 @@ void do_softirq_own_stack(void)
call_on_stack(__do_softirq, isp);
}
+#endif
void __handle_irq(struct irq_desc *desc, struct pt_regs *regs)
{
diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c
index 440eed558..7cfc4e6b7 100644
--- a/arch/x86/kernel/irq_64.c
+++ b/arch/x86/kernel/irq_64.c
@@ -72,7 +72,9 @@ int irq_init_percpu_irqstack(unsigned int cpu)
return map_irq_stack(cpu);
}
+#ifndef CONFIG_PREEMPT_RT
void do_softirq_own_stack(void)
{
run_on_irqstack_cond(__do_softirq, NULL);
}
+#endif
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index d2d206ff6..06479a5e2 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8573,6 +8573,14 @@ int kvm_arch_init(void *opaque)
goto out;
}
+#ifdef CONFIG_PREEMPT_RT
+ if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
+ pr_err("RT requires X86_FEATURE_CONSTANT_TSC\n");
+ r = -EOPNOTSUPP;
+ goto out;
+ }
+#endif
+
r = -ENOMEM;
x86_emulator_cache = kvm_alloc_emulator_cache();
diff --git a/arch/x86/mm/highmem_32.c b/arch/x86/mm/highmem_32.c
index 075fe5131..2c54b76d8 100644
--- a/arch/x86/mm/highmem_32.c
+++ b/arch/x86/mm/highmem_32.c
@@ -4,65 +4,6 @@
#include <linux/swap.h> /* for totalram_pages */
#include <linux/memblock.h>
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
- unsigned long vaddr;
- int idx, type;
-
- type = kmap_atomic_idx_push();
- idx = type + KM_TYPE_NR*smp_processor_id();
- vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
- BUG_ON(!pte_none(*(kmap_pte-idx)));
- set_pte(kmap_pte-idx, mk_pte(page, prot));
- arch_flush_lazy_mmu_mode();
-
- return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-/*
- * This is the same as kmap_atomic() but can map memory that doesn't
- * have a struct page associated with it.
- */
-void *kmap_atomic_pfn(unsigned long pfn)
-{
- return kmap_atomic_prot_pfn(pfn, kmap_prot);
-}
-EXPORT_SYMBOL_GPL(kmap_atomic_pfn);
-
-void kunmap_atomic_high(void *kvaddr)
-{
- unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-
- if (vaddr >= __fix_to_virt(FIX_KMAP_END) &&
- vaddr <= __fix_to_virt(FIX_KMAP_BEGIN)) {
- int idx, type;
-
- type = kmap_atomic_idx();
- idx = type + KM_TYPE_NR * smp_processor_id();
-
-#ifdef CONFIG_DEBUG_HIGHMEM
- WARN_ON_ONCE(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-#endif
- /*
- * Force other mappings to Oops if they'll try to access this
- * pte without first remap it. Keeping stale mappings around
- * is a bad idea also, in case the page changes cacheability
- * attributes or becomes a protected page in a hypervisor.
- */
- kpte_clear_flush(kmap_pte-idx, vaddr);
- kmap_atomic_idx_pop();
- arch_flush_lazy_mmu_mode();
- }
-#ifdef CONFIG_DEBUG_HIGHMEM
- else {
- BUG_ON(vaddr < PAGE_OFFSET);
- BUG_ON(vaddr >= (unsigned long)high_memory);
- }
-#endif
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
-
void __init set_highmem_pages_init(void)
{
struct zone *zone;
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 7c055259d..da31c2635 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -394,19 +394,6 @@ repeat:
return last_map_addr;
}
-pte_t *kmap_pte;
-
-static void __init kmap_init(void)
-{
- unsigned long kmap_vstart;
-
- /*
- * Cache the first kmap pte:
- */
- kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
- kmap_pte = virt_to_kpte(kmap_vstart);
-}
-
#ifdef CONFIG_HIGHMEM
static void __init permanent_kmaps_init(pgd_t *pgd_base)
{
@@ -712,8 +699,6 @@ void __init paging_init(void)
__flush_tlb_all();
- kmap_init();
-
/*
* NOTE: at this point the bootmem allocator is fully available.
*/
diff --git a/arch/x86/mm/iomap_32.c b/arch/x86/mm/iomap_32.c
index f60398aeb..9aaa756dd 100644
--- a/arch/x86/mm/iomap_32.c
+++ b/arch/x86/mm/iomap_32.c
@@ -44,28 +44,7 @@ void iomap_free(resource_size_t base, unsigned long size)
}
EXPORT_SYMBOL_GPL(iomap_free);
-void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
-{
- unsigned long vaddr;
- int idx, type;
-
- preempt_disable();
- pagefault_disable();
-
- type = kmap_atomic_idx_push();
- idx = type + KM_TYPE_NR * smp_processor_id();
- vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
- set_pte(kmap_pte - idx, pfn_pte(pfn, prot));
- arch_flush_lazy_mmu_mode();
-
- return (void *)vaddr;
-}
-
-/*
- * Map 'pfn' using protections 'prot'
- */
-void __iomem *
-iomap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
+void __iomem *__iomap_local_pfn_prot(unsigned long pfn, pgprot_t prot)
{
/*
* For non-PAT systems, translate non-WB request to UC- just in
@@ -81,36 +60,6 @@ iomap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
/* Filter out unsupported __PAGE_KERNEL* bits: */
pgprot_val(prot) &= __default_kernel_pte_mask;
- return (void __force __iomem *) kmap_atomic_prot_pfn(pfn, prot);
-}
-EXPORT_SYMBOL_GPL(iomap_atomic_prot_pfn);
-
-void
-iounmap_atomic(void __iomem *kvaddr)
-{
- unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-
- if (vaddr >= __fix_to_virt(FIX_KMAP_END) &&
- vaddr <= __fix_to_virt(FIX_KMAP_BEGIN)) {
- int idx, type;
-
- type = kmap_atomic_idx();
- idx = type + KM_TYPE_NR * smp_processor_id();
-
-#ifdef CONFIG_DEBUG_HIGHMEM
- WARN_ON_ONCE(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-#endif
- /*
- * Force other mappings to Oops if they'll try to access this
- * pte without first remap it. Keeping stale mappings around
- * is a bad idea also, in case the page changes cacheability
- * attributes or becomes a protected page in a hypervisor.
- */
- kpte_clear_flush(kmap_pte-idx, vaddr);
- kmap_atomic_idx_pop();
- }
-
- pagefault_enable();
- preempt_enable();
+ return (void __force __iomem *)__kmap_local_pfn_prot(pfn, prot);
}
-EXPORT_SYMBOL_GPL(iounmap_atomic);
+EXPORT_SYMBOL_GPL(__iomap_local_pfn_prot);
diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index 87e08ad38..03cbf6b53 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -666,6 +666,7 @@ endchoice
config HIGHMEM
bool "High Memory Support"
depends on MMU
+ select KMAP_LOCAL
help
Linux can use the full amount of RAM in the system by
default. However, the default MMUv2 setup only maps the
diff --git a/arch/xtensa/include/asm/fixmap.h b/arch/xtensa/include/asm/fixmap.h
index a06ffb0c6..92049b61c 100644
--- a/arch/xtensa/include/asm/fixmap.h
+++ b/arch/xtensa/include/asm/fixmap.h
@@ -16,7 +16,7 @@
#ifdef CONFIG_HIGHMEM
#include <linux/threads.h>
#include <linux/pgtable.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
#endif
/*
@@ -39,7 +39,7 @@ enum fixed_addresses {
/* reserved pte's for temporary kernel mappings */
FIX_KMAP_BEGIN,
FIX_KMAP_END = FIX_KMAP_BEGIN +
- (KM_TYPE_NR * NR_CPUS * DCACHE_N_COLORS) - 1,
+ (KM_MAX_IDX * NR_CPUS * DCACHE_N_COLORS) - 1,
#endif
__end_of_fixed_addresses
};
diff --git a/arch/xtensa/include/asm/highmem.h b/arch/xtensa/include/asm/highmem.h
index eac503215..0fc3b1ceb 100644
--- a/arch/xtensa/include/asm/highmem.h
+++ b/arch/xtensa/include/asm/highmem.h
@@ -16,9 +16,8 @@
#include <linux/pgtable.h>
#include <asm/cacheflush.h>
#include <asm/fixmap.h>
-#include <asm/kmap_types.h>
-#define PKMAP_BASE ((FIXADDR_START - \
+#define PKMAP_BASE ((FIXADDR_START - \
(LAST_PKMAP + 1) * PAGE_SIZE) & PMD_MASK)
#define LAST_PKMAP (PTRS_PER_PTE * DCACHE_N_COLORS)
#define LAST_PKMAP_MASK (LAST_PKMAP - 1)
@@ -68,6 +67,15 @@ static inline void flush_cache_kmaps(void)
flush_cache_all();
}
+enum fixed_addresses kmap_local_map_idx(int type, unsigned long pfn);
+#define arch_kmap_local_map_idx kmap_local_map_idx
+
+enum fixed_addresses kmap_local_unmap_idx(int type, unsigned long addr);
+#define arch_kmap_local_unmap_idx kmap_local_unmap_idx
+
+#define arch_kmap_local_post_unmap(vaddr) \
+ local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE)
+
void kmap_init(void);
#endif
diff --git a/arch/xtensa/include/asm/spinlock_types.h b/arch/xtensa/include/asm/spinlock_types.h
index 64c938925..dc846323b 100644
--- a/arch/xtensa/include/asm/spinlock_types.h
+++ b/arch/xtensa/include/asm/spinlock_types.h
@@ -2,10 +2,6 @@
#ifndef __ASM_SPINLOCK_TYPES_H
#define __ASM_SPINLOCK_TYPES_H
-#if !defined(__LINUX_SPINLOCK_TYPES_H) && !defined(__ASM_SPINLOCK_H)
-# error "please don't include this file directly"
-#endif
-
#include <asm-generic/qspinlock_types.h>
#include <asm-generic/qrwlock_types.h>
diff --git a/arch/xtensa/mm/highmem.c b/arch/xtensa/mm/highmem.c
index 673196fe8..0735ca5e8 100644
--- a/arch/xtensa/mm/highmem.c
+++ b/arch/xtensa/mm/highmem.c
@@ -12,8 +12,6 @@
#include <linux/highmem.h>
#include <asm/tlbflush.h>
-static pte_t *kmap_pte;
-
#if DCACHE_WAY_SIZE > PAGE_SIZE
unsigned int last_pkmap_nr_arr[DCACHE_N_COLORS];
wait_queue_head_t pkmap_map_wait_arr[DCACHE_N_COLORS];
@@ -33,59 +31,25 @@ static inline void kmap_waitqueues_init(void)
static inline enum fixed_addresses kmap_idx(int type, unsigned long color)
{
- return (type + KM_TYPE_NR * smp_processor_id()) * DCACHE_N_COLORS +
+ return (type + KM_MAX_IDX * smp_processor_id()) * DCACHE_N_COLORS +
color;
}
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
+enum fixed_addresses kmap_local_map_idx(int type, unsigned long pfn)
{
- enum fixed_addresses idx;
- unsigned long vaddr;
-
- idx = kmap_idx(kmap_atomic_idx_push(),
- DCACHE_ALIAS(page_to_phys(page)));
- vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
- BUG_ON(!pte_none(*(kmap_pte + idx)));
-#endif
- set_pte(kmap_pte + idx, mk_pte(page, prot));
-
- return (void *)vaddr;
+ return kmap_idx(type, DCACHE_ALIAS(pfn << PAGE_SHIFT));
}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-void kunmap_atomic_high(void *kvaddr)
+enum fixed_addresses kmap_local_unmap_idx(int type, unsigned long addr)
{
- if (kvaddr >= (void *)FIXADDR_START &&
- kvaddr < (void *)FIXADDR_TOP) {
- int idx = kmap_idx(kmap_atomic_idx(),
- DCACHE_ALIAS((unsigned long)kvaddr));
-
- /*
- * Force other mappings to Oops if they'll try to access this
- * pte without first remap it. Keeping stale mappings around
- * is a bad idea also, in case the page changes cacheability
- * attributes or becomes a protected page in a hypervisor.
- */
- pte_clear(&init_mm, kvaddr, kmap_pte + idx);
- local_flush_tlb_kernel_range((unsigned long)kvaddr,
- (unsigned long)kvaddr + PAGE_SIZE);
-
- kmap_atomic_idx_pop();
- }
+ return kmap_idx(type, DCACHE_ALIAS(addr));
}
-EXPORT_SYMBOL(kunmap_atomic_high);
void __init kmap_init(void)
{
- unsigned long kmap_vstart;
-
/* Check if this memory layout is broken because PKMAP overlaps
* page table.
*/
BUILD_BUG_ON(PKMAP_BASE < TLBTEMP_BASE_1 + TLBTEMP_SIZE);
- /* cache the first kmap pte */
- kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
- kmap_pte = virt_to_kpte(kmap_vstart);
kmap_waitqueues_init();
}
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 376f16616..083f13d8e 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -47,7 +47,7 @@
bool mq_unfair_dtag = true;
module_param_named(unfair_dtag, mq_unfair_dtag, bool, 0444);
-static DEFINE_PER_CPU(struct list_head, blk_cpu_done);
+static DEFINE_PER_CPU(struct llist_head, blk_cpu_done);
static void blk_mq_poll_stats_start(struct request_queue *q);
static void blk_mq_poll_stats_fn(struct blk_stat_callback *cb);
@@ -655,80 +655,29 @@ void blk_mq_end_request(struct request *rq, blk_status_t error)
}
EXPORT_SYMBOL(blk_mq_end_request);
-/*
- * Softirq action handler - move entries to local list and loop over them
- * while passing them to the queue registered handler.
- */
-static __latent_entropy void blk_done_softirq(struct softirq_action *h)
+static void blk_complete_reqs(struct llist_head *list)
{
- struct list_head *cpu_list, local_list;
-
- local_irq_disable();
- cpu_list = this_cpu_ptr(&blk_cpu_done);
- list_replace_init(cpu_list, &local_list);
- local_irq_enable();
-
- while (!list_empty(&local_list)) {
- struct request *rq;
+ struct llist_node *entry = llist_reverse_order(llist_del_all(list));
+ struct request *rq, *next;
- rq = list_entry(local_list.next, struct request, ipi_list);
- list_del_init(&rq->ipi_list);
+ llist_for_each_entry_safe(rq, next, entry, ipi_list)
rq->q->mq_ops->complete(rq);
- }
}
-static void blk_mq_trigger_softirq(struct request *rq)
+static __latent_entropy void blk_done_softirq(struct softirq_action *h)
{
- struct list_head *list;
- unsigned long flags;
-
- local_irq_save(flags);
- list = this_cpu_ptr(&blk_cpu_done);
- list_add_tail(&rq->ipi_list, list);
-
- /*
- * If the list only contains our just added request, signal a raise of
- * the softirq. If there are already entries there, someone already
- * raised the irq but it hasn't run yet.
- */
- if (list->next == &rq->ipi_list)
- raise_softirq_irqoff(BLOCK_SOFTIRQ);
- local_irq_restore(flags);
+ blk_complete_reqs(this_cpu_ptr(&blk_cpu_done));
}
static int blk_softirq_cpu_dead(unsigned int cpu)
{
- /*
- * If a CPU goes away, splice its entries to the current CPU
- * and trigger a run of the softirq
- */
- local_irq_disable();
- list_splice_init(&per_cpu(blk_cpu_done, cpu),
- this_cpu_ptr(&blk_cpu_done));
- raise_softirq_irqoff(BLOCK_SOFTIRQ);
- local_irq_enable();
-
+ blk_complete_reqs(&per_cpu(blk_cpu_done, cpu));
return 0;
}
-
static void __blk_mq_complete_request_remote(void *data)
{
- struct request *rq = data;
-
- /*
- * For most of single queue controllers, there is only one irq vector
- * for handling I/O completion, and the only irq's affinity is set
- * to all possible CPUs. On most of ARCHs, this affinity means the irq
- * is handled on one specific CPU.
- *
- * So complete I/O requests in softirq context in case of single queue
- * devices to avoid degrading I/O performance due to irqsoff latency.
- */
- if (rq->q->nr_hw_queues == 1)
- blk_mq_trigger_softirq(rq);
- else
- rq->q->mq_ops->complete(rq);
+ __raise_softirq_irqoff(BLOCK_SOFTIRQ);
}
static inline bool blk_mq_complete_need_ipi(struct request *rq)
@@ -738,6 +687,14 @@ static inline bool blk_mq_complete_need_ipi(struct request *rq)
if (!IS_ENABLED(CONFIG_SMP) ||
!test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags))
return false;
+ /*
+ * With force threaded interrupts enabled, raising softirq from an SMP
+ * function call will always result in waking the ksoftirqd thread.
+ * This is probably worse than completing the request on a different
+ * cache domain.
+ */
+ if (force_irqthreads)
+ return false;
/* same CPU or cache domain? Complete locally */
if (cpu == rq->mq_ctx->cpu ||
@@ -749,6 +706,31 @@ static inline bool blk_mq_complete_need_ipi(struct request *rq)
return cpu_online(rq->mq_ctx->cpu);
}
+static void blk_mq_complete_send_ipi(struct request *rq)
+{
+ struct llist_head *list;
+ unsigned int cpu;
+
+ cpu = rq->mq_ctx->cpu;
+ list = &per_cpu(blk_cpu_done, cpu);
+ if (llist_add(&rq->ipi_list, list)) {
+ rq->csd.func = __blk_mq_complete_request_remote;
+ rq->csd.info = rq;
+ smp_call_function_single_async(cpu, &rq->csd);
+ }
+}
+
+static void blk_mq_raise_softirq(struct request *rq)
+{
+ struct llist_head *list;
+
+ preempt_disable();
+ list = this_cpu_ptr(&blk_cpu_done);
+ if (llist_add(&rq->ipi_list, list))
+ raise_softirq(BLOCK_SOFTIRQ);
+ preempt_enable();
+}
+
bool blk_mq_complete_request_remote(struct request *rq)
{
WRITE_ONCE(rq->state, MQ_RQ_COMPLETE);
@@ -761,15 +743,15 @@ bool blk_mq_complete_request_remote(struct request *rq)
return false;
if (blk_mq_complete_need_ipi(rq)) {
- INIT_CSD(&rq->csd, __blk_mq_complete_request_remote, rq);
- smp_call_function_single_async(rq->mq_ctx->cpu, &rq->csd);
- } else {
- if (rq->q->nr_hw_queues > 1)
- return false;
- blk_mq_trigger_softirq(rq);
+ blk_mq_complete_send_ipi(rq);
+ return true;
}
- return true;
+ if (rq->q->nr_hw_queues == 1) {
+ blk_mq_raise_softirq(rq);
+ return true;
+ }
+ return false;
}
EXPORT_SYMBOL_GPL(blk_mq_complete_request_remote);
@@ -1708,14 +1690,14 @@ static void __blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async,
return;
if (!async && !(hctx->flags & BLK_MQ_F_BLOCKING)) {
- int cpu = get_cpu();
+ int cpu = get_cpu_light();
if (cpumask_test_cpu(cpu, hctx->cpumask)) {
__blk_mq_run_hw_queue(hctx);
- put_cpu();
+ put_cpu_light();
return;
}
- put_cpu();
+ put_cpu_light();
}
/*
@@ -4266,7 +4248,7 @@ static int __init blk_mq_init(void)
int i;
for_each_possible_cpu(i)
- INIT_LIST_HEAD(&per_cpu(blk_cpu_done, i));
+ init_llist_head(&per_cpu(blk_cpu_done, i));
open_softirq(BLOCK_SOFTIRQ, blk_done_softirq);
cpuhp_setup_state_nocalls(CPUHP_BLOCK_SOFTIRQ_DEAD,
diff --git a/crypto/cryptd.c b/crypto/cryptd.c
index ca3a40fc7..884647620 100644
--- a/crypto/cryptd.c
+++ b/crypto/cryptd.c
@@ -36,6 +36,7 @@ static struct workqueue_struct *cryptd_wq;
struct cryptd_cpu_queue {
struct crypto_queue queue;
struct work_struct work;
+ spinlock_t qlock;
};
struct cryptd_queue {
@@ -110,6 +111,7 @@ static int cryptd_init_queue(struct cryptd_queue *queue,
cpu_queue = per_cpu_ptr(queue->cpu_queue, cpu);
crypto_init_queue(&cpu_queue->queue, max_cpu_qlen);
INIT_WORK(&cpu_queue->work, cryptd_queue_worker);
+ spin_lock_init(&cpu_queue->qlock);
}
pr_info("cryptd: max_cpu_qlen set to %d\n", max_cpu_qlen);
return 0;
@@ -134,8 +136,10 @@ static int cryptd_enqueue_request(struct cryptd_queue *queue,
struct cryptd_cpu_queue *cpu_queue;
refcount_t *refcnt;
- local_bh_disable();
- cpu_queue = this_cpu_ptr(queue->cpu_queue);
+ cpu_queue = raw_cpu_ptr(queue->cpu_queue);
+ spin_lock_bh(&cpu_queue->qlock);
+ // cpu = smp_processor_id();
+
err = crypto_enqueue_request(&cpu_queue->queue, request);
refcnt = crypto_tfm_ctx(request->tfm);
@@ -151,7 +155,7 @@ static int cryptd_enqueue_request(struct cryptd_queue *queue,
refcount_inc(refcnt);
out:
- local_bh_enable();
+ spin_unlock_bh(&cpu_queue->qlock);
return err;
}
@@ -168,10 +172,11 @@ static void cryptd_queue_worker(struct work_struct *work)
/*
* Only handle one request at a time to avoid hogging crypto workqueue.
*/
- local_bh_disable();
+ spin_lock_bh(&cpu_queue->qlock);
backlog = crypto_get_backlog(&cpu_queue->queue);
req = crypto_dequeue_request(&cpu_queue->queue);
- local_bh_enable();
+ spin_unlock_bh(&cpu_queue->qlock);
+
if (!req)
return;
diff --git a/drivers/atm/eni.c b/drivers/atm/eni.c
index 9fcc49be4..a31ffe16e 100644
--- a/drivers/atm/eni.c
+++ b/drivers/atm/eni.c
@@ -2056,7 +2056,7 @@ static int eni_send(struct atm_vcc *vcc,struct sk_buff *skb)
}
submitted++;
ATM_SKB(skb)->vcc = vcc;
- tasklet_disable(&ENI_DEV(vcc->dev)->task);
+ tasklet_disable_in_atomic(&ENI_DEV(vcc->dev)->task);
res = do_tx(skb);
tasklet_enable(&ENI_DEV(vcc->dev)->task);
if (res == enq_ok) return 0;
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 8b1ef1dc7..4f0f77971 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -59,6 +59,40 @@ static void zram_free_page(struct zram *zram, size_t index);
static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,
u32 index, int offset, struct bio *bio);
+#ifdef CONFIG_PREEMPT_RT
+static void zram_meta_init_table_locks(struct zram *zram, size_t num_pages)
+{
+ size_t index;
+
+ for (index = 0; index < num_pages; index++)
+ spin_lock_init(&zram->table[index].lock);
+}
+
+static int zram_slot_trylock(struct zram *zram, u32 index)
+{
+ int ret;
+
+ ret = spin_trylock(&zram->table[index].lock);
+ if (ret)
+ __set_bit(ZRAM_LOCK, &zram->table[index].flags);
+ return ret;
+}
+
+static void zram_slot_lock(struct zram *zram, u32 index)
+{
+ spin_lock(&zram->table[index].lock);
+ __set_bit(ZRAM_LOCK, &zram->table[index].flags);
+}
+
+static void zram_slot_unlock(struct zram *zram, u32 index)
+{
+ __clear_bit(ZRAM_LOCK, &zram->table[index].flags);
+ spin_unlock(&zram->table[index].lock);
+}
+
+#else
+
+static void zram_meta_init_table_locks(struct zram *zram, size_t num_pages) { }
static int zram_slot_trylock(struct zram *zram, u32 index)
{
@@ -74,6 +108,7 @@ static void zram_slot_unlock(struct zram *zram, u32 index)
{
bit_spin_unlock(ZRAM_LOCK, &zram->table[index].flags);
}
+#endif
static inline bool init_done(struct zram *zram)
{
@@ -1295,6 +1330,7 @@ static bool zram_meta_alloc(struct zram *zram, u64 disksize)
if (!huge_class_size)
huge_class_size = zs_huge_class_size(zram->mem_pool);
+ zram_meta_init_table_locks(zram, num_pages);
return true;
}
diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h
index eb13d0299..d118a57e7 100644
--- a/drivers/block/zram/zram_drv.h
+++ b/drivers/block/zram/zram_drv.h
@@ -69,6 +69,7 @@ struct zram_table_entry {
unsigned long element;
};
unsigned long flags;
+ spinlock_t lock;
#ifdef CONFIG_ZRAM_MEMORY_TRACKING
ktime_t ac_time;
#endif
diff --git a/drivers/char/tpm/tpm-dev-common.c b/drivers/char/tpm/tpm-dev-common.c
index a9e7f5a82..30b4c288c 100644
--- a/drivers/char/tpm/tpm-dev-common.c
+++ b/drivers/char/tpm/tpm-dev-common.c
@@ -20,7 +20,6 @@
#include "tpm-dev.h"
static struct workqueue_struct *tpm_dev_wq;
-static DEFINE_MUTEX(tpm_dev_wq_lock);
static ssize_t tpm_dev_transmit(struct tpm_chip *chip, struct tpm_space *space,
u8 *buf, size_t bufsiz)
diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c
index 3e1bb28b7..c26ed0ce6 100644
--- a/drivers/char/tpm/tpm_tis.c
+++ b/drivers/char/tpm/tpm_tis.c
@@ -50,6 +50,31 @@ static inline struct tpm_tis_tcg_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *da
return container_of(data, struct tpm_tis_tcg_phy, priv);
}
+#ifdef CONFIG_PREEMPT_RT
+/*
+ * Flushes previous write operations to chip so that a subsequent
+ * ioread*()s won't stall a cpu.
+ */
+static inline void tpm_tis_flush(void __iomem *iobase)
+{
+ ioread8(iobase + TPM_ACCESS(0));
+}
+#else
+#define tpm_tis_flush(iobase) do { } while (0)
+#endif
+
+static inline void tpm_tis_iowrite8(u8 b, void __iomem *iobase, u32 addr)
+{
+ iowrite8(b, iobase + addr);
+ tpm_tis_flush(iobase);
+}
+
+static inline void tpm_tis_iowrite32(u32 b, void __iomem *iobase, u32 addr)
+{
+ iowrite32(b, iobase + addr);
+ tpm_tis_flush(iobase);
+}
+
static int interrupts = -1;
module_param(interrupts, int, 0444);
MODULE_PARM_DESC(interrupts, "Enable interrupts");
@@ -186,7 +211,7 @@ static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
while (len--)
- iowrite8(*value++, phy->iobase + addr);
+ tpm_tis_iowrite8(*value++, phy->iobase, addr);
return 0;
}
@@ -213,7 +238,7 @@ static int tpm_tcg_write32(struct tpm_tis_data *data, u32 addr, u32 value)
{
struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
- iowrite32(value, phy->iobase + addr);
+ tpm_tis_iowrite32(value, phy->iobase, addr);
return 0;
}
diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c
index 9b2471d12..7d94e1cbc 100644
--- a/drivers/firewire/ohci.c
+++ b/drivers/firewire/ohci.c
@@ -2597,7 +2597,7 @@ static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
struct driver_data *driver_data = packet->driver_data;
int ret = -ENOENT;
- tasklet_disable(&ctx->tasklet);
+ tasklet_disable_in_atomic(&ctx->tasklet);
if (packet->ack != 0)
goto out;
@@ -3517,7 +3517,7 @@ static int ohci_flush_iso_completions(struct fw_iso_context *base)
struct iso_context *ctx = container_of(base, struct iso_context, base);
int ret = 0;
- tasklet_disable(&ctx->context.tasklet);
+ tasklet_disable_in_atomic(&ctx->context.tasklet);
if (!test_and_set_bit_lock(0, &ctx->flushing_completions)) {
context_tasklet((unsigned long)&ctx->context);
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index fa830f7bf..d48577c49 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -67,7 +67,7 @@ struct mm_struct efi_mm = {
struct workqueue_struct *efi_rts_wq;
-static bool disable_runtime;
+static bool disable_runtime = IS_ENABLED(CONFIG_PREEMPT_RT);
static int __init setup_noefi(char *arg)
{
disable_runtime = true;
@@ -98,6 +98,9 @@ static int __init parse_efi_cmdline(char *str)
if (parse_option_str(str, "noruntime"))
disable_runtime = true;
+ if (parse_option_str(str, "runtime"))
+ disable_runtime = false;
+
if (parse_option_str(str, "nosoftreserve"))
set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags);
diff --git a/drivers/gpu/drm/i915/display/intel_sprite.c b/drivers/gpu/drm/i915/display/intel_sprite.c
index 12f7128b7..a65061e3e 100644
--- a/drivers/gpu/drm/i915/display/intel_sprite.c
+++ b/drivers/gpu/drm/i915/display/intel_sprite.c
@@ -118,7 +118,8 @@ void intel_pipe_update_start(const struct intel_crtc_state *new_crtc_state)
"PSR idle timed out 0x%x, atomic update may fail\n",
psr_status);
- local_irq_disable();
+ if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+ local_irq_disable();
crtc->debug.min_vbl = min;
crtc->debug.max_vbl = max;
@@ -143,11 +144,13 @@ void intel_pipe_update_start(const struct intel_crtc_state *new_crtc_state)
break;
}
- local_irq_enable();
+ if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+ local_irq_enable();
timeout = schedule_timeout(timeout);
- local_irq_disable();
+ if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+ local_irq_disable();
}
finish_wait(wq, &wait);
@@ -180,7 +183,8 @@ void intel_pipe_update_start(const struct intel_crtc_state *new_crtc_state)
return;
irq_disable:
- local_irq_disable();
+ if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+ local_irq_disable();
}
/**
@@ -218,7 +222,8 @@ void intel_pipe_update_end(struct intel_crtc_state *new_crtc_state)
new_crtc_state->uapi.event = NULL;
}
- local_irq_enable();
+ if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+ local_irq_enable();
if (intel_vgpu_active(dev_priv))
return;
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
index 0c083af5a..2abf043d3 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
@@ -1080,7 +1080,7 @@ static void reloc_cache_reset(struct reloc_cache *cache, struct i915_execbuffer
struct i915_ggtt *ggtt = cache_to_ggtt(cache);
intel_gt_flush_ggtt_writes(ggtt->vm.gt);
- io_mapping_unmap_atomic((void __iomem *)vaddr);
+ io_mapping_unmap_local((void __iomem *)vaddr);
if (drm_mm_node_allocated(&cache->node)) {
ggtt->vm.clear_range(&ggtt->vm,
@@ -1146,7 +1146,7 @@ static void *reloc_iomap(struct drm_i915_gem_object *obj,
if (cache->vaddr) {
intel_gt_flush_ggtt_writes(ggtt->vm.gt);
- io_mapping_unmap_atomic((void __force __iomem *) unmask_page(cache->vaddr));
+ io_mapping_unmap_local((void __force __iomem *) unmask_page(cache->vaddr));
} else {
struct i915_vma *vma;
int err;
@@ -1194,8 +1194,7 @@ static void *reloc_iomap(struct drm_i915_gem_object *obj,
offset += page << PAGE_SHIFT;
}
- vaddr = (void __force *)io_mapping_map_atomic_wc(&ggtt->iomap,
- offset);
+ vaddr = (void __force *)io_mapping_map_local_wc(&ggtt->iomap, offset);
cache->page = page;
cache->vaddr = (unsigned long)vaddr;
diff --git a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c
index 0040b4765..3f4f85478 100644
--- a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c
+++ b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c
@@ -342,10 +342,9 @@ void intel_breadcrumbs_park(struct intel_breadcrumbs *b)
/* Kick the work once more to drain the signalers */
irq_work_sync(&b->irq_work);
while (unlikely(READ_ONCE(b->irq_armed))) {
- local_irq_disable();
- signal_irq_work(&b->irq_work);
- local_irq_enable();
+ irq_work_queue(&b->irq_work);
cond_resched();
+ irq_work_sync(&b->irq_work);
}
GEM_BUG_ON(!list_empty(&b->signalers));
}
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_pm.c b/drivers/gpu/drm/i915/gt/intel_engine_pm.c
index f9fdbd79c..fe7118415 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_pm.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_pm.c
@@ -60,9 +60,10 @@ static int __engine_unpark(struct intel_wakeref *wf)
static inline unsigned long __timeline_mark_lock(struct intel_context *ce)
{
- unsigned long flags;
+ unsigned long flags = 0;
- local_irq_save(flags);
+ if (!force_irqthreads)
+ local_irq_save(flags);
mutex_acquire(&ce->timeline->mutex.dep_map, 2, 0, _THIS_IP_);
return flags;
@@ -72,7 +73,8 @@ static inline void __timeline_mark_unlock(struct intel_context *ce,
unsigned long flags)
{
mutex_release(&ce->timeline->mutex.dep_map, _THIS_IP_);
- local_irq_restore(flags);
+ if (!force_irqthreads)
+ local_irq_restore(flags);
}
#else
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 58276694c..88944c3b1 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -355,22 +355,15 @@ gtt_user_read(struct io_mapping *mapping,
char __user *user_data, int length)
{
void __iomem *vaddr;
- unsigned long unwritten;
+ bool fail = false;
/* We can use the cpu mem copy function because this is X86. */
- vaddr = io_mapping_map_atomic_wc(mapping, base);
- unwritten = __copy_to_user_inatomic(user_data,
- (void __force *)vaddr + offset,
- length);
- io_mapping_unmap_atomic(vaddr);
- if (unwritten) {
- vaddr = io_mapping_map_wc(mapping, base, PAGE_SIZE);
- unwritten = copy_to_user(user_data,
- (void __force *)vaddr + offset,
- length);
- io_mapping_unmap(vaddr);
- }
- return unwritten;
+ vaddr = io_mapping_map_local_wc(mapping, base);
+ if (copy_to_user(user_data, (void __force *)vaddr + offset, length))
+ fail = true;
+ io_mapping_unmap_local(vaddr);
+
+ return fail;
}
static int
@@ -539,21 +532,14 @@ ggtt_write(struct io_mapping *mapping,
char __user *user_data, int length)
{
void __iomem *vaddr;
- unsigned long unwritten;
+ bool fail = false;
/* We can use the cpu mem copy function because this is X86. */
- vaddr = io_mapping_map_atomic_wc(mapping, base);
- unwritten = __copy_from_user_inatomic_nocache((void __force *)vaddr + offset,
- user_data, length);
- io_mapping_unmap_atomic(vaddr);
- if (unwritten) {
- vaddr = io_mapping_map_wc(mapping, base, PAGE_SIZE);
- unwritten = copy_from_user((void __force *)vaddr + offset,
- user_data, length);
- io_mapping_unmap(vaddr);
- }
-
- return unwritten;
+ vaddr = io_mapping_map_local_wc(mapping, base);
+ if (copy_from_user((void __force *)vaddr + offset, user_data, length))
+ fail = true;
+ io_mapping_unmap_local(vaddr);
+ return fail;
}
/**
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 759f523c6..7339a42ab 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -847,6 +847,7 @@ static bool i915_get_crtc_scanoutpos(struct drm_crtc *_crtc,
spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
/* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */
+ preempt_disable_rt();
/* Get optional system timestamp before query. */
if (stime)
@@ -898,6 +899,7 @@ static bool i915_get_crtc_scanoutpos(struct drm_crtc *_crtc,
*etime = ktime_get();
/* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */
+ preempt_enable_rt();
spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
diff --git a/drivers/gpu/drm/i915/i915_trace.h b/drivers/gpu/drm/i915/i915_trace.h
index a4addcc64..396b65986 100644
--- a/drivers/gpu/drm/i915/i915_trace.h
+++ b/drivers/gpu/drm/i915/i915_trace.h
@@ -2,6 +2,10 @@
#if !defined(_I915_TRACE_H_) || defined(TRACE_HEADER_MULTI_READ)
#define _I915_TRACE_H_
+#ifdef CONFIG_PREEMPT_RT
+#define NOTRACE
+#endif
+
#include <linux/stringify.h>
#include <linux/types.h>
#include <linux/tracepoint.h>
@@ -778,7 +782,7 @@ DEFINE_EVENT(i915_request, i915_request_add,
TP_ARGS(rq)
);
-#if defined(CONFIG_DRM_I915_LOW_LEVEL_TRACEPOINTS)
+#if defined(CONFIG_DRM_I915_LOW_LEVEL_TRACEPOINTS) && !defined(NOTRACE)
DEFINE_EVENT(i915_request, i915_request_submit,
TP_PROTO(struct i915_request *rq),
TP_ARGS(rq)
diff --git a/drivers/gpu/drm/i915/selftests/i915_gem.c b/drivers/gpu/drm/i915/selftests/i915_gem.c
index 412e21604..432493183 100644
--- a/drivers/gpu/drm/i915/selftests/i915_gem.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem.c
@@ -57,12 +57,12 @@ static void trash_stolen(struct drm_i915_private *i915)
ggtt->vm.insert_page(&ggtt->vm, dma, slot, I915_CACHE_NONE, 0);
- s = io_mapping_map_atomic_wc(&ggtt->iomap, slot);
+ s = io_mapping_map_local_wc(&ggtt->iomap, slot);
for (x = 0; x < PAGE_SIZE / sizeof(u32); x++) {
prng = next_pseudo_random32(prng);
iowrite32(prng, &s[x]);
}
- io_mapping_unmap_atomic(s);
+ io_mapping_unmap_local(s);
}
ggtt->vm.clear_range(&ggtt->vm, slot, PAGE_SIZE);
diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
index 65e28c4cd..ca483285f 100644
--- a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
@@ -1201,9 +1201,9 @@ static int igt_ggtt_page(void *arg)
u64 offset = tmp.start + order[n] * PAGE_SIZE;
u32 __iomem *vaddr;
- vaddr = io_mapping_map_atomic_wc(&ggtt->iomap, offset);
+ vaddr = io_mapping_map_local_wc(&ggtt->iomap, offset);
iowrite32(n, vaddr + n);
- io_mapping_unmap_atomic(vaddr);
+ io_mapping_unmap_local(vaddr);
}
intel_gt_flush_ggtt_writes(ggtt->vm.gt);
@@ -1213,9 +1213,9 @@ static int igt_ggtt_page(void *arg)
u32 __iomem *vaddr;
u32 val;
- vaddr = io_mapping_map_atomic_wc(&ggtt->iomap, offset);
+ vaddr = io_mapping_map_local_wc(&ggtt->iomap, offset);
val = ioread32(vaddr + n);
- io_mapping_unmap_atomic(vaddr);
+ io_mapping_unmap_local(vaddr);
if (val != n) {
pr_err("insert page failed: found %d, expected %d\n",
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/devinit/fbmem.h b/drivers/gpu/drm/nouveau/nvkm/subdev/devinit/fbmem.h
index 6c5bbff12..411f91ee2 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/devinit/fbmem.h
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/devinit/fbmem.h
@@ -60,19 +60,19 @@ fbmem_fini(struct io_mapping *fb)
static inline u32
fbmem_peek(struct io_mapping *fb, u32 off)
{
- u8 __iomem *p = io_mapping_map_atomic_wc(fb, off & PAGE_MASK);
+ u8 __iomem *p = io_mapping_map_local_wc(fb, off & PAGE_MASK);
u32 val = ioread32(p + (off & ~PAGE_MASK));
- io_mapping_unmap_atomic(p);
+ io_mapping_unmap_local(p);
return val;
}
static inline void
fbmem_poke(struct io_mapping *fb, u32 off, u32 val)
{
- u8 __iomem *p = io_mapping_map_atomic_wc(fb, off & PAGE_MASK);
+ u8 __iomem *p = io_mapping_map_local_wc(fb, off & PAGE_MASK);
iowrite32(val, p + (off & ~PAGE_MASK));
wmb();
- io_mapping_unmap_atomic(p);
+ io_mapping_unmap_local(p);
}
static inline bool
diff --git a/drivers/gpu/drm/qxl/qxl_image.c b/drivers/gpu/drm/qxl/qxl_image.c
index 60ab7151b..93f92ccd4 100644
--- a/drivers/gpu/drm/qxl/qxl_image.c
+++ b/drivers/gpu/drm/qxl/qxl_image.c
@@ -124,12 +124,12 @@ qxl_image_init_helper(struct qxl_device *qdev,
wrong (check the bitmaps are sent correctly
first) */
- ptr = qxl_bo_kmap_atomic_page(qdev, chunk_bo, 0);
+ ptr = qxl_bo_kmap_local_page(qdev, chunk_bo, 0);
chunk = ptr;
chunk->data_size = height * chunk_stride;
chunk->prev_chunk = 0;
chunk->next_chunk = 0;
- qxl_bo_kunmap_atomic_page(qdev, chunk_bo, ptr);
+ qxl_bo_kunmap_local_page(qdev, chunk_bo, ptr);
{
void *k_data, *i_data;
@@ -143,7 +143,7 @@ qxl_image_init_helper(struct qxl_device *qdev,
i_data = (void *)data;
while (remain > 0) {
- ptr = qxl_bo_kmap_atomic_page(qdev, chunk_bo, page << PAGE_SHIFT);
+ ptr = qxl_bo_kmap_local_page(qdev, chunk_bo, page << PAGE_SHIFT);
if (page == 0) {
chunk = ptr;
@@ -157,7 +157,7 @@ qxl_image_init_helper(struct qxl_device *qdev,
memcpy(k_data, i_data, size);
- qxl_bo_kunmap_atomic_page(qdev, chunk_bo, ptr);
+ qxl_bo_kunmap_local_page(qdev, chunk_bo, ptr);
i_data += size;
remain -= size;
page++;
@@ -175,10 +175,10 @@ qxl_image_init_helper(struct qxl_device *qdev,
page_offset = offset_in_page(out_offset);
size = min((int)(PAGE_SIZE - page_offset), remain);
- ptr = qxl_bo_kmap_atomic_page(qdev, chunk_bo, page_base);
+ ptr = qxl_bo_kmap_local_page(qdev, chunk_bo, page_base);
k_data = ptr + page_offset;
memcpy(k_data, i_data, size);
- qxl_bo_kunmap_atomic_page(qdev, chunk_bo, ptr);
+ qxl_bo_kunmap_local_page(qdev, chunk_bo, ptr);
remain -= size;
i_data += size;
out_offset += size;
@@ -189,7 +189,7 @@ qxl_image_init_helper(struct qxl_device *qdev,
qxl_bo_kunmap(chunk_bo);
image_bo = dimage->bo;
- ptr = qxl_bo_kmap_atomic_page(qdev, image_bo, 0);
+ ptr = qxl_bo_kmap_local_page(qdev, image_bo, 0);
image = ptr;
image->descriptor.id = 0;
@@ -212,7 +212,7 @@ qxl_image_init_helper(struct qxl_device *qdev,
break;
default:
DRM_ERROR("unsupported image bit depth\n");
- qxl_bo_kunmap_atomic_page(qdev, image_bo, ptr);
+ qxl_bo_kunmap_local_page(qdev, image_bo, ptr);
return -EINVAL;
}
image->u.bitmap.flags = QXL_BITMAP_TOP_DOWN;
@@ -222,7 +222,7 @@ qxl_image_init_helper(struct qxl_device *qdev,
image->u.bitmap.palette = 0;
image->u.bitmap.data = qxl_bo_physical_address(qdev, chunk_bo, 0);
- qxl_bo_kunmap_atomic_page(qdev, image_bo, ptr);
+ qxl_bo_kunmap_local_page(qdev, image_bo, ptr);
return 0;
}
diff --git a/drivers/gpu/drm/qxl/qxl_ioctl.c b/drivers/gpu/drm/qxl/qxl_ioctl.c
index 9a02c4871..758c484c7 100644
--- a/drivers/gpu/drm/qxl/qxl_ioctl.c
+++ b/drivers/gpu/drm/qxl/qxl_ioctl.c
@@ -88,11 +88,11 @@ apply_reloc(struct qxl_device *qdev, struct qxl_reloc_info *info)
{
void *reloc_page;
- reloc_page = qxl_bo_kmap_atomic_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
+ reloc_page = qxl_bo_kmap_local_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
*(uint64_t *)(reloc_page + (info->dst_offset & ~PAGE_MASK)) = qxl_bo_physical_address(qdev,
info->src_bo,
info->src_offset);
- qxl_bo_kunmap_atomic_page(qdev, info->dst_bo, reloc_page);
+ qxl_bo_kunmap_local_page(qdev, info->dst_bo, reloc_page);
}
static void
@@ -104,9 +104,9 @@ apply_surf_reloc(struct qxl_device *qdev, struct qxl_reloc_info *info)
if (info->src_bo && !info->src_bo->is_primary)
id = info->src_bo->surface_id;
- reloc_page = qxl_bo_kmap_atomic_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
+ reloc_page = qxl_bo_kmap_local_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
*(uint32_t *)(reloc_page + (info->dst_offset & ~PAGE_MASK)) = id;
- qxl_bo_kunmap_atomic_page(qdev, info->dst_bo, reloc_page);
+ qxl_bo_kunmap_local_page(qdev, info->dst_bo, reloc_page);
}
/* return holding the reference to this object */
@@ -148,7 +148,6 @@ static int qxl_process_single_command(struct qxl_device *qdev,
struct qxl_bo *cmd_bo;
void *fb_cmd;
int i, ret, num_relocs;
- int unwritten;
switch (cmd->type) {
case QXL_CMD_DRAW:
@@ -184,21 +183,21 @@ static int qxl_process_single_command(struct qxl_device *qdev,
goto out_free_reloc;
/* TODO copy slow path code from i915 */
- fb_cmd = qxl_bo_kmap_atomic_page(qdev, cmd_bo, (release->release_offset & PAGE_MASK));
- unwritten = __copy_from_user_inatomic_nocache
- (fb_cmd + sizeof(union qxl_release_info) + (release->release_offset & ~PAGE_MASK),
- u64_to_user_ptr(cmd->command), cmd->command_size);
+ fb_cmd = qxl_bo_kmap_local_page(qdev, cmd_bo, (release->release_offset & PAGE_MASK));
- {
+ if (copy_from_user(fb_cmd + sizeof(union qxl_release_info) +
+ (release->release_offset & ~PAGE_MASK),
+ u64_to_user_ptr(cmd->command), cmd->command_size)) {
+ ret = -EFAULT;
+ } else {
struct qxl_drawable *draw = fb_cmd;
draw->mm_time = qdev->rom->mm_clock;
}
- qxl_bo_kunmap_atomic_page(qdev, cmd_bo, fb_cmd);
- if (unwritten) {
- DRM_ERROR("got unwritten %d\n", unwritten);
- ret = -EFAULT;
+ qxl_bo_kunmap_local_page(qdev, cmd_bo, fb_cmd);
+ if (ret) {
+ DRM_ERROR("copy from user failed %d\n", ret);
goto out_free_release;
}
diff --git a/drivers/gpu/drm/qxl/qxl_object.c b/drivers/gpu/drm/qxl/qxl_object.c
index 544a9e4df..5ee5171d4 100644
--- a/drivers/gpu/drm/qxl/qxl_object.c
+++ b/drivers/gpu/drm/qxl/qxl_object.c
@@ -173,8 +173,8 @@ int qxl_bo_kmap(struct qxl_bo *bo, void **ptr)
return 0;
}
-void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev,
- struct qxl_bo *bo, int page_offset)
+void *qxl_bo_kmap_local_page(struct qxl_device *qdev,
+ struct qxl_bo *bo, int page_offset)
{
unsigned long offset;
void *rptr;
@@ -189,7 +189,7 @@ void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev,
goto fallback;
offset = bo->tbo.mem.start << PAGE_SHIFT;
- return io_mapping_map_atomic_wc(map, offset + page_offset);
+ return io_mapping_map_local_wc(map, offset + page_offset);
fallback:
if (bo->kptr) {
rptr = bo->kptr + (page_offset * PAGE_SIZE);
@@ -215,14 +215,14 @@ void qxl_bo_kunmap(struct qxl_bo *bo)
ttm_bo_kunmap(&bo->kmap);
}
-void qxl_bo_kunmap_atomic_page(struct qxl_device *qdev,
- struct qxl_bo *bo, void *pmap)
+void qxl_bo_kunmap_local_page(struct qxl_device *qdev,
+ struct qxl_bo *bo, void *pmap)
{
if ((bo->tbo.mem.mem_type != TTM_PL_VRAM) &&
(bo->tbo.mem.mem_type != TTM_PL_PRIV))
goto fallback;
- io_mapping_unmap_atomic(pmap);
+ io_mapping_unmap_local(pmap);
return;
fallback:
qxl_bo_kunmap(bo);
diff --git a/drivers/gpu/drm/qxl/qxl_object.h b/drivers/gpu/drm/qxl/qxl_object.h
index 5762ea40d..6ae89b1b3 100644
--- a/drivers/gpu/drm/qxl/qxl_object.h
+++ b/drivers/gpu/drm/qxl/qxl_object.h
@@ -89,8 +89,8 @@ extern int qxl_bo_create(struct qxl_device *qdev,
struct qxl_bo **bo_ptr);
extern int qxl_bo_kmap(struct qxl_bo *bo, void **ptr);
extern void qxl_bo_kunmap(struct qxl_bo *bo);
-void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev, struct qxl_bo *bo, int page_offset);
-void qxl_bo_kunmap_atomic_page(struct qxl_device *qdev, struct qxl_bo *bo, void *map);
+void *qxl_bo_kmap_local_page(struct qxl_device *qdev, struct qxl_bo *bo, int page_offset);
+void qxl_bo_kunmap_local_page(struct qxl_device *qdev, struct qxl_bo *bo, void *map);
extern struct qxl_bo *qxl_bo_ref(struct qxl_bo *bo);
extern void qxl_bo_unref(struct qxl_bo **bo);
extern int qxl_bo_pin(struct qxl_bo *bo);
diff --git a/drivers/gpu/drm/qxl/qxl_release.c b/drivers/gpu/drm/qxl/qxl_release.c
index b2a475a0c..b665a33b4 100644
--- a/drivers/gpu/drm/qxl/qxl_release.c
+++ b/drivers/gpu/drm/qxl/qxl_release.c
@@ -414,7 +414,7 @@ union qxl_release_info *qxl_release_map(struct qxl_device *qdev,
union qxl_release_info *info;
struct qxl_bo *bo = release->release_bo;
- ptr = qxl_bo_kmap_atomic_page(qdev, bo, release->release_offset & PAGE_MASK);
+ ptr = qxl_bo_kmap_local_page(qdev, bo, release->release_offset & PAGE_MASK);
if (!ptr)
return NULL;
info = ptr + (release->release_offset & ~PAGE_MASK);
@@ -429,7 +429,7 @@ void qxl_release_unmap(struct qxl_device *qdev,
void *ptr;
ptr = ((void *)info) - (release->release_offset & ~PAGE_MASK);
- qxl_bo_kunmap_atomic_page(qdev, bo, ptr);
+ qxl_bo_kunmap_local_page(qdev, bo, ptr);
}
void qxl_release_fence_buffer_objects(struct qxl_release *release)
diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c
index 07d23a1e6..add8e6044 100644
--- a/drivers/gpu/drm/radeon/radeon_display.c
+++ b/drivers/gpu/drm/radeon/radeon_display.c
@@ -1828,6 +1828,7 @@ int radeon_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
struct radeon_device *rdev = dev->dev_private;
/* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */
+ preempt_disable_rt();
/* Get optional system timestamp before query. */
if (stime)
@@ -1920,6 +1921,7 @@ int radeon_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
*etime = ktime_get();
/* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */
+ preempt_enable_rt();
/* Decode into vertical and horizontal scanout position. */
*vpos = position & 0x1fff;
diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
index 20a5434c6..17b2df35e 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -181,13 +181,15 @@ static int ttm_copy_io_ttm_page(struct ttm_tt *ttm, void *src,
return -ENOMEM;
src = (void *)((unsigned long)src + (page << PAGE_SHIFT));
- dst = kmap_atomic_prot(d, prot);
- if (!dst)
- return -ENOMEM;
+ /*
+ * Ensure that a highmem page is mapped with the correct
+ * pgprot. For non highmem the mapping is already there.
+ */
+ dst = kmap_local_page_prot(d, prot);
memcpy_fromio(dst, src, PAGE_SIZE);
- kunmap_atomic(dst);
+ kunmap_local(dst);
return 0;
}
@@ -203,13 +205,15 @@ static int ttm_copy_ttm_io_page(struct ttm_tt *ttm, void *dst,
return -ENOMEM;
dst = (void *)((unsigned long)dst + (page << PAGE_SHIFT));
- src = kmap_atomic_prot(s, prot);
- if (!src)
- return -ENOMEM;
+ /*
+ * Ensure that a highmem page is mapped with the correct
+ * pgprot. For non highmem the mapping is already there.
+ */
+ src = kmap_local_page_prot(s, prot);
memcpy_toio(dst, src, PAGE_SIZE);
- kunmap_atomic(src);
+ kunmap_local(src);
return 0;
}
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_blit.c b/drivers/gpu/drm/vmwgfx/vmwgfx_blit.c
index e8d66182c..71dba228f 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_blit.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_blit.c
@@ -375,12 +375,12 @@ static int vmw_bo_cpu_blit_line(struct vmw_bo_blit_line_data *d,
copy_size = min_t(u32, copy_size, PAGE_SIZE - src_page_offset);
if (unmap_src) {
- kunmap_atomic(d->src_addr);
+ kunmap_local(d->src_addr);
d->src_addr = NULL;
}
if (unmap_dst) {
- kunmap_atomic(d->dst_addr);
+ kunmap_local(d->dst_addr);
d->dst_addr = NULL;
}
@@ -388,12 +388,8 @@ static int vmw_bo_cpu_blit_line(struct vmw_bo_blit_line_data *d,
if (WARN_ON_ONCE(dst_page >= d->dst_num_pages))
return -EINVAL;
- d->dst_addr =
- kmap_atomic_prot(d->dst_pages[dst_page],
- d->dst_prot);
- if (!d->dst_addr)
- return -ENOMEM;
-
+ d->dst_addr = kmap_local_page_prot(d->dst_pages[dst_page],
+ d->dst_prot);
d->mapped_dst = dst_page;
}
@@ -401,12 +397,8 @@ static int vmw_bo_cpu_blit_line(struct vmw_bo_blit_line_data *d,
if (WARN_ON_ONCE(src_page >= d->src_num_pages))
return -EINVAL;
- d->src_addr =
- kmap_atomic_prot(d->src_pages[src_page],
- d->src_prot);
- if (!d->src_addr)
- return -ENOMEM;
-
+ d->src_addr = kmap_local_page_prot(d->src_pages[src_page],
+ d->src_prot);
d->mapped_src = src_page;
}
diff->do_cpy(diff, d->dst_addr + dst_page_offset,
@@ -436,8 +428,10 @@ static int vmw_bo_cpu_blit_line(struct vmw_bo_blit_line_data *d,
*
* Performs a CPU blit from one buffer object to another avoiding a full
* bo vmap which may exhaust- or fragment vmalloc space.
- * On supported architectures (x86), we're using kmap_atomic which avoids
- * cross-processor TLB- and cache flushes and may, on non-HIGHMEM systems
+ *
+ * On supported architectures (x86), we're using kmap_local_prot() which
+ * avoids cross-processor TLB- and cache flushes. kmap_local_prot() will
+ * either map a highmem page with the proper pgprot on HIGHMEM=y systems or
* reference already set-up mappings.
*
* Neither of the buffer objects may be placed in PCI memory
@@ -500,9 +494,9 @@ int vmw_bo_cpu_blit(struct ttm_buffer_object *dst,
}
out:
if (d.src_addr)
- kunmap_atomic(d.src_addr);
+ kunmap_local(d.src_addr);
if (d.dst_addr)
- kunmap_atomic(d.dst_addr);
+ kunmap_local(d.dst_addr);
return ret;
}
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index 601660bca..0829e7dde 100644
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -19,6 +19,7 @@
#include <linux/atomic.h>
#include <linux/hyperv.h>
#include <linux/interrupt.h>
+#include <linux/irq.h>
#include "hv_trace.h"
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index e99400f3a..396ec97f1 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -22,6 +22,7 @@
#include <linux/clockchips.h>
#include <linux/cpu.h>
#include <linux/sched/task_stack.h>
+#include <linux/irq.h>
#include <linux/delay.h>
#include <linux/notifier.h>
@@ -1307,6 +1308,8 @@ static void vmbus_isr(void)
void *page_addr = hv_cpu->synic_event_page;
struct hv_message *msg;
union hv_synic_event_flags *event;
+ struct pt_regs *regs = get_irq_regs();
+ u64 ip = regs ? instruction_pointer(regs) : 0;
bool handled = false;
if (unlikely(page_addr == NULL))
@@ -1359,7 +1362,8 @@ static void vmbus_isr(void)
* buffer and call into Hyper-V to transfer the data.
*/
static void hv_kmsg_dump(struct kmsg_dumper *dumper,
- enum kmsg_dump_reason reason)
+ enum kmsg_dump_reason reason,
+ struct kmsg_dumper_iter *iter)
{
size_t bytes_written;
phys_addr_t panic_pa;
@@ -1374,7 +1378,7 @@ static void hv_kmsg_dump(struct kmsg_dumper *dumper,
* Write dump contents to the page. No need to synchronize; panic should
* be single-threaded.
*/
- kmsg_dump_get_buffer(dumper, false, hv_panic_page, HV_HYP_PAGE_SIZE,
+ kmsg_dump_get_buffer(iter, false, hv_panic_page, HV_HYP_PAGE_SIZE,
&bytes_written);
if (bytes_written)
hyperv_report_panic_msg(panic_pa, bytes_written);
diff --git a/drivers/irqchip/irq-gic-v4.c b/drivers/irqchip/irq-gic-v4.c
index 1b3d7b43d..a5c0d38a3 100644
--- a/drivers/irqchip/irq-gic-v4.c
+++ b/drivers/irqchip/irq-gic-v4.c
@@ -86,7 +86,7 @@
static struct irq_domain *gic_domain;
static const struct irq_domain_ops *vpe_domain_ops;
static const struct irq_domain_ops *sgi_domain_ops;
-static bool vtimer_irqbypass;
+bool vtimer_irqbypass;
static bool has_v4_1(void)
{
diff --git a/drivers/leds/trigger/Kconfig b/drivers/leds/trigger/Kconfig
index ce9429ca6..29ccbd6ac 100644
--- a/drivers/leds/trigger/Kconfig
+++ b/drivers/leds/trigger/Kconfig
@@ -64,6 +64,7 @@ config LEDS_TRIGGER_BACKLIGHT
config LEDS_TRIGGER_CPU
bool "LED CPU Trigger"
+ depends on !PREEMPT_RT
help
This allows LEDs to be controlled by active CPUs. This shows
the active CPUs across an array of LEDs so you can see which
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 126b9ecfe..19c90abbd 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -2217,8 +2217,9 @@ static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
struct raid5_percpu *percpu;
unsigned long cpu;
- cpu = get_cpu();
+ cpu = get_cpu_light();
percpu = per_cpu_ptr(conf->percpu, cpu);
+ spin_lock(&percpu->lock);
if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) {
ops_run_biofill(sh);
overlap_clear++;
@@ -2277,7 +2278,8 @@ static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
if (test_and_clear_bit(R5_Overlap, &dev->flags))
wake_up(&sh->raid_conf->wait_for_overlap);
}
- put_cpu();
+ spin_unlock(&percpu->lock);
+ put_cpu_light();
}
static void free_stripe(struct kmem_cache *sc, struct stripe_head *sh)
@@ -7097,6 +7099,7 @@ static int raid456_cpu_up_prepare(unsigned int cpu, struct hlist_node *node)
__func__, cpu);
return -ENOMEM;
}
+ spin_lock_init(&per_cpu_ptr(conf->percpu, cpu)->lock);
return 0;
}
diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h
index d1780d086..7a5f4eba8 100644
--- a/drivers/md/raid5.h
+++ b/drivers/md/raid5.h
@@ -635,6 +635,7 @@ struct r5conf {
int recovery_disabled;
/* per cpu variables */
struct raid5_percpu {
+ spinlock_t lock; /* Protection for -RT */
struct page *spare_page; /* Used when checking P/Q in raid6 */
void *scribble; /* space for constructing buffer
* lists and performing address
diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c
index 774970bfc..6bc2c728a 100644
--- a/drivers/mtd/mtdoops.c
+++ b/drivers/mtd/mtdoops.c
@@ -267,7 +267,8 @@ static void find_next_position(struct mtdoops_context *cxt)
}
static void mtdoops_do_dump(struct kmsg_dumper *dumper,
- enum kmsg_dump_reason reason)
+ enum kmsg_dump_reason reason,
+ struct kmsg_dumper_iter *iter)
{
struct mtdoops_context *cxt = container_of(dumper,
struct mtdoops_context, dump);
@@ -276,7 +277,7 @@ static void mtdoops_do_dump(struct kmsg_dumper *dumper,
if (reason == KMSG_DUMP_OOPS && !dump_oops)
return;
- kmsg_dump_get_buffer(dumper, true, cxt->oops_buf + MTDOOPS_HEADER_SIZE,
+ kmsg_dump_get_buffer(iter, true, cxt->oops_buf + MTDOOPS_HEADER_SIZE,
record_size - MTDOOPS_HEADER_SIZE, NULL);
if (reason != KMSG_DUMP_OOPS) {
diff --git a/drivers/net/ethernet/chelsio/cxgb/common.h b/drivers/net/ethernet/chelsio/cxgb/common.h
index 647506064..0321be773 100644
--- a/drivers/net/ethernet/chelsio/cxgb/common.h
+++ b/drivers/net/ethernet/chelsio/cxgb/common.h
@@ -238,7 +238,6 @@ struct adapter {
int msg_enable;
u32 mmio_len;
- struct work_struct ext_intr_handler_task;
struct adapter_params params;
/* Terminator modules. */
@@ -257,6 +256,7 @@ struct adapter {
/* guards async operations */
spinlock_t async_lock ____cacheline_aligned;
+ u32 pending_thread_intr;
u32 slow_intr_mask;
int t1powersave;
};
@@ -334,8 +334,7 @@ void t1_interrupts_enable(adapter_t *adapter);
void t1_interrupts_disable(adapter_t *adapter);
void t1_interrupts_clear(adapter_t *adapter);
int t1_elmer0_ext_intr_handler(adapter_t *adapter);
-void t1_elmer0_ext_intr(adapter_t *adapter);
-int t1_slow_intr_handler(adapter_t *adapter);
+irqreturn_t t1_slow_intr_handler(adapter_t *adapter);
int t1_link_start(struct cphy *phy, struct cmac *mac, struct link_config *lc);
const struct board_info *t1_get_board_info(unsigned int board_id);
@@ -347,7 +346,6 @@ int t1_get_board_rev(adapter_t *adapter, const struct board_info *bi,
int t1_init_hw_modules(adapter_t *adapter);
int t1_init_sw_modules(adapter_t *adapter, const struct board_info *bi);
void t1_free_sw_modules(adapter_t *adapter);
-void t1_fatal_err(adapter_t *adapter);
void t1_link_changed(adapter_t *adapter, int port_id);
void t1_link_negotiated(adapter_t *adapter, int port_id, int link_stat,
int speed, int duplex, int pause);
diff --git a/drivers/net/ethernet/chelsio/cxgb/cxgb2.c b/drivers/net/ethernet/chelsio/cxgb/cxgb2.c
index 1311eac9e..c827273c4 100644
--- a/drivers/net/ethernet/chelsio/cxgb/cxgb2.c
+++ b/drivers/net/ethernet/chelsio/cxgb/cxgb2.c
@@ -211,9 +211,10 @@ static int cxgb_up(struct adapter *adapter)
t1_interrupts_clear(adapter);
adapter->params.has_msi = !disable_msi && !pci_enable_msi(adapter->pdev);
- err = request_irq(adapter->pdev->irq, t1_interrupt,
- adapter->params.has_msi ? 0 : IRQF_SHARED,
- adapter->name, adapter);
+ err = request_threaded_irq(adapter->pdev->irq, t1_interrupt,
+ t1_interrupt_thread,
+ adapter->params.has_msi ? 0 : IRQF_SHARED,
+ adapter->name, adapter);
if (err) {
if (adapter->params.has_msi)
pci_disable_msi(adapter->pdev);
@@ -924,51 +925,6 @@ static void mac_stats_task(struct work_struct *work)
spin_unlock(&adapter->work_lock);
}
-/*
- * Processes elmer0 external interrupts in process context.
- */
-static void ext_intr_task(struct work_struct *work)
-{
- struct adapter *adapter =
- container_of(work, struct adapter, ext_intr_handler_task);
-
- t1_elmer0_ext_intr_handler(adapter);
-
- /* Now reenable external interrupts */
- spin_lock_irq(&adapter->async_lock);
- adapter->slow_intr_mask |= F_PL_INTR_EXT;
- writel(F_PL_INTR_EXT, adapter->regs + A_PL_CAUSE);
- writel(adapter->slow_intr_mask | F_PL_INTR_SGE_DATA,
- adapter->regs + A_PL_ENABLE);
- spin_unlock_irq(&adapter->async_lock);
-}
-
-/*
- * Interrupt-context handler for elmer0 external interrupts.
- */
-void t1_elmer0_ext_intr(struct adapter *adapter)
-{
- /*
- * Schedule a task to handle external interrupts as we require
- * a process context. We disable EXT interrupts in the interim
- * and let the task reenable them when it's done.
- */
- adapter->slow_intr_mask &= ~F_PL_INTR_EXT;
- writel(adapter->slow_intr_mask | F_PL_INTR_SGE_DATA,
- adapter->regs + A_PL_ENABLE);
- schedule_work(&adapter->ext_intr_handler_task);
-}
-
-void t1_fatal_err(struct adapter *adapter)
-{
- if (adapter->flags & FULL_INIT_DONE) {
- t1_sge_stop(adapter->sge);
- t1_interrupts_disable(adapter);
- }
- pr_alert("%s: encountered fatal error, operation suspended\n",
- adapter->name);
-}
-
static const struct net_device_ops cxgb_netdev_ops = {
.ndo_open = cxgb_open,
.ndo_stop = cxgb_close,
@@ -1070,8 +1026,6 @@ static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
spin_lock_init(&adapter->async_lock);
spin_lock_init(&adapter->mac_lock);
- INIT_WORK(&adapter->ext_intr_handler_task,
- ext_intr_task);
INIT_DELAYED_WORK(&adapter->stats_update_task,
mac_stats_task);
diff --git a/drivers/net/ethernet/chelsio/cxgb/sge.c b/drivers/net/ethernet/chelsio/cxgb/sge.c
index 2d9c2b5a6..cda01f22c 100644
--- a/drivers/net/ethernet/chelsio/cxgb/sge.c
+++ b/drivers/net/ethernet/chelsio/cxgb/sge.c
@@ -940,10 +940,11 @@ void t1_sge_intr_clear(struct sge *sge)
/*
* SGE 'Error' interrupt handler
*/
-int t1_sge_intr_error_handler(struct sge *sge)
+bool t1_sge_intr_error_handler(struct sge *sge)
{
struct adapter *adapter = sge->adapter;
u32 cause = readl(adapter->regs + A_SG_INT_CAUSE);
+ bool wake = false;
if (adapter->port[0].dev->hw_features & NETIF_F_TSO)
cause &= ~F_PACKET_TOO_BIG;
@@ -967,11 +968,14 @@ int t1_sge_intr_error_handler(struct sge *sge)
sge->stats.pkt_mismatch++;
pr_alert("%s: SGE packet mismatch\n", adapter->name);
}
- if (cause & SGE_INT_FATAL)
- t1_fatal_err(adapter);
+ if (cause & SGE_INT_FATAL) {
+ t1_interrupts_disable(adapter);
+ adapter->pending_thread_intr |= F_PL_INTR_SGE_ERR;
+ wake = true;
+ }
writel(cause, adapter->regs + A_SG_INT_CAUSE);
- return 0;
+ return wake;
}
const struct sge_intr_counts *t1_sge_get_intr_counts(const struct sge *sge)
@@ -1619,11 +1623,46 @@ int t1_poll(struct napi_struct *napi, int budget)
return work_done;
}
+irqreturn_t t1_interrupt_thread(int irq, void *data)
+{
+ struct adapter *adapter = data;
+ u32 pending_thread_intr;
+
+ spin_lock_irq(&adapter->async_lock);
+ pending_thread_intr = adapter->pending_thread_intr;
+ adapter->pending_thread_intr = 0;
+ spin_unlock_irq(&adapter->async_lock);
+
+ if (!pending_thread_intr)
+ return IRQ_NONE;
+
+ if (pending_thread_intr & F_PL_INTR_EXT)
+ t1_elmer0_ext_intr_handler(adapter);
+
+ /* This error is fatal, interrupts remain off */
+ if (pending_thread_intr & F_PL_INTR_SGE_ERR) {
+ pr_alert("%s: encountered fatal error, operation suspended\n",
+ adapter->name);
+ t1_sge_stop(adapter->sge);
+ return IRQ_HANDLED;
+ }
+
+ spin_lock_irq(&adapter->async_lock);
+ adapter->slow_intr_mask |= F_PL_INTR_EXT;
+
+ writel(F_PL_INTR_EXT, adapter->regs + A_PL_CAUSE);
+ writel(adapter->slow_intr_mask | F_PL_INTR_SGE_DATA,
+ adapter->regs + A_PL_ENABLE);
+ spin_unlock_irq(&adapter->async_lock);
+
+ return IRQ_HANDLED;
+}
+
irqreturn_t t1_interrupt(int irq, void *data)
{
struct adapter *adapter = data;
struct sge *sge = adapter->sge;
- int handled;
+ irqreturn_t handled;
if (likely(responses_pending(adapter))) {
writel(F_PL_INTR_SGE_DATA, adapter->regs + A_PL_CAUSE);
@@ -1645,10 +1684,10 @@ irqreturn_t t1_interrupt(int irq, void *data)
handled = t1_slow_intr_handler(adapter);
spin_unlock(&adapter->async_lock);
- if (!handled)
+ if (handled == IRQ_NONE)
sge->stats.unhandled_irqs++;
- return IRQ_RETVAL(handled != 0);
+ return handled;
}
/*
diff --git a/drivers/net/ethernet/chelsio/cxgb/sge.h b/drivers/net/ethernet/chelsio/cxgb/sge.h
index a1ba591b3..716705b96 100644
--- a/drivers/net/ethernet/chelsio/cxgb/sge.h
+++ b/drivers/net/ethernet/chelsio/cxgb/sge.h
@@ -74,6 +74,7 @@ struct sge *t1_sge_create(struct adapter *, struct sge_params *);
int t1_sge_configure(struct sge *, struct sge_params *);
int t1_sge_set_coalesce_params(struct sge *, struct sge_params *);
void t1_sge_destroy(struct sge *);
+irqreturn_t t1_interrupt_thread(int irq, void *data);
irqreturn_t t1_interrupt(int irq, void *cookie);
int t1_poll(struct napi_struct *, int);
@@ -81,7 +82,7 @@ netdev_tx_t t1_start_xmit(struct sk_buff *skb, struct net_device *dev);
void t1_vlan_mode(struct adapter *adapter, netdev_features_t features);
void t1_sge_start(struct sge *);
void t1_sge_stop(struct sge *);
-int t1_sge_intr_error_handler(struct sge *);
+bool t1_sge_intr_error_handler(struct sge *sge);
void t1_sge_intr_enable(struct sge *);
void t1_sge_intr_disable(struct sge *);
void t1_sge_intr_clear(struct sge *);
diff --git a/drivers/net/ethernet/chelsio/cxgb/subr.c b/drivers/net/ethernet/chelsio/cxgb/subr.c
index ea0f8741d..310add28f 100644
--- a/drivers/net/ethernet/chelsio/cxgb/subr.c
+++ b/drivers/net/ethernet/chelsio/cxgb/subr.c
@@ -170,7 +170,7 @@ void t1_link_changed(adapter_t *adapter, int port_id)
t1_link_negotiated(adapter, port_id, link_ok, speed, duplex, fc);
}
-static int t1_pci_intr_handler(adapter_t *adapter)
+static bool t1_pci_intr_handler(adapter_t *adapter)
{
u32 pcix_cause;
@@ -179,9 +179,13 @@ static int t1_pci_intr_handler(adapter_t *adapter)
if (pcix_cause) {
pci_write_config_dword(adapter->pdev, A_PCICFG_INTR_CAUSE,
pcix_cause);
- t1_fatal_err(adapter); /* PCI errors are fatal */
+ /* PCI errors are fatal */
+ t1_interrupts_disable(adapter);
+ adapter->pending_thread_intr |= F_PL_INTR_SGE_ERR;
+ pr_alert("%s: PCI error encountered.\n", adapter->name);
+ return true;
}
- return 0;
+ return false;
}
#ifdef CONFIG_CHELSIO_T1_1G
@@ -210,13 +214,16 @@ static int fpga_phy_intr_handler(adapter_t *adapter)
/*
* Slow path interrupt handler for FPGAs.
*/
-static int fpga_slow_intr(adapter_t *adapter)
+static irqreturn_t fpga_slow_intr(adapter_t *adapter)
{
u32 cause = readl(adapter->regs + A_PL_CAUSE);
+ irqreturn_t ret = IRQ_NONE;
cause &= ~F_PL_INTR_SGE_DATA;
- if (cause & F_PL_INTR_SGE_ERR)
- t1_sge_intr_error_handler(adapter->sge);
+ if (cause & F_PL_INTR_SGE_ERR) {
+ if (t1_sge_intr_error_handler(adapter->sge))
+ ret = IRQ_WAKE_THREAD;
+ }
if (cause & FPGA_PCIX_INTERRUPT_GMAC)
fpga_phy_intr_handler(adapter);
@@ -231,14 +238,19 @@ static int fpga_slow_intr(adapter_t *adapter)
/* Clear TP interrupt */
writel(tp_cause, adapter->regs + FPGA_TP_ADDR_INTERRUPT_CAUSE);
}
- if (cause & FPGA_PCIX_INTERRUPT_PCIX)
- t1_pci_intr_handler(adapter);
+ if (cause & FPGA_PCIX_INTERRUPT_PCIX) {
+ if (t1_pci_intr_handler(adapter))
+ ret = IRQ_WAKE_THREAD;
+ }
/* Clear the interrupts just processed. */
if (cause)
writel(cause, adapter->regs + A_PL_CAUSE);
- return cause != 0;
+ if (ret != IRQ_NONE)
+ return ret;
+
+ return cause == 0 ? IRQ_NONE : IRQ_HANDLED;
}
#endif
@@ -842,31 +854,45 @@ void t1_interrupts_clear(adapter_t* adapter)
/*
* Slow path interrupt handler for ASICs.
*/
-static int asic_slow_intr(adapter_t *adapter)
+static irqreturn_t asic_slow_intr(adapter_t *adapter)
{
u32 cause = readl(adapter->regs + A_PL_CAUSE);
+ irqreturn_t ret = IRQ_HANDLED;
cause &= adapter->slow_intr_mask;
if (!cause)
- return 0;
- if (cause & F_PL_INTR_SGE_ERR)
- t1_sge_intr_error_handler(adapter->sge);
+ return IRQ_NONE;
+ if (cause & F_PL_INTR_SGE_ERR) {
+ if (t1_sge_intr_error_handler(adapter->sge))
+ ret = IRQ_WAKE_THREAD;
+ }
if (cause & F_PL_INTR_TP)
t1_tp_intr_handler(adapter->tp);
if (cause & F_PL_INTR_ESPI)
t1_espi_intr_handler(adapter->espi);
- if (cause & F_PL_INTR_PCIX)
- t1_pci_intr_handler(adapter);
- if (cause & F_PL_INTR_EXT)
- t1_elmer0_ext_intr(adapter);
+ if (cause & F_PL_INTR_PCIX) {
+ if (t1_pci_intr_handler(adapter))
+ ret = IRQ_WAKE_THREAD;
+ }
+ if (cause & F_PL_INTR_EXT) {
+ /* Wake the threaded interrupt to handle external interrupts as
+ * we require a process context. We disable EXT interrupts in
+ * the interim and let the thread reenable them when it's done.
+ */
+ adapter->pending_thread_intr |= F_PL_INTR_EXT;
+ adapter->slow_intr_mask &= ~F_PL_INTR_EXT;
+ writel(adapter->slow_intr_mask | F_PL_INTR_SGE_DATA,
+ adapter->regs + A_PL_ENABLE);
+ ret = IRQ_WAKE_THREAD;
+ }
/* Clear the interrupts just processed. */
writel(cause, adapter->regs + A_PL_CAUSE);
readl(adapter->regs + A_PL_CAUSE); /* flush writes */
- return 1;
+ return ret;
}
-int t1_slow_intr_handler(adapter_t *adapter)
+irqreturn_t t1_slow_intr_handler(adapter_t *adapter)
{
#ifdef CONFIG_CHELSIO_T1_1G
if (!t1_is_asic(adapter))
diff --git a/drivers/net/ethernet/dlink/sundance.c b/drivers/net/ethernet/dlink/sundance.c
index e3a885891..df0eab479 100644
--- a/drivers/net/ethernet/dlink/sundance.c
+++ b/drivers/net/ethernet/dlink/sundance.c
@@ -963,7 +963,7 @@ static void tx_timeout(struct net_device *dev, unsigned int txqueue)
unsigned long flag;
netif_stop_queue(dev);
- tasklet_disable(&np->tx_tasklet);
+ tasklet_disable_in_atomic(&np->tx_tasklet);
iowrite16(0, ioaddr + IntrEnable);
printk(KERN_WARNING "%s: Transmit timed out, TxStatus %2.2x "
"TxFrameId %2.2x,"
diff --git a/drivers/net/ethernet/jme.c b/drivers/net/ethernet/jme.c
index 4185ca3dd..cf5c33d0f 100644
--- a/drivers/net/ethernet/jme.c
+++ b/drivers/net/ethernet/jme.c
@@ -1265,9 +1265,9 @@ jme_stop_shutdown_timer(struct jme_adapter *jme)
jwrite32f(jme, JME_APMC, apmc);
}
-static void jme_link_change_tasklet(struct tasklet_struct *t)
+static void jme_link_change_work(struct work_struct *work)
{
- struct jme_adapter *jme = from_tasklet(jme, t, linkch_task);
+ struct jme_adapter *jme = container_of(work, struct jme_adapter, linkch_task);
struct net_device *netdev = jme->dev;
int rc;
@@ -1510,7 +1510,7 @@ jme_intr_msi(struct jme_adapter *jme, u32 intrstat)
* all other events are ignored
*/
jwrite32(jme, JME_IEVE, intrstat);
- tasklet_schedule(&jme->linkch_task);
+ schedule_work(&jme->linkch_task);
goto out_reenable;
}
@@ -1832,7 +1832,6 @@ jme_open(struct net_device *netdev)
jme_clear_pm_disable_wol(jme);
JME_NAPI_ENABLE(jme);
- tasklet_setup(&jme->linkch_task, jme_link_change_tasklet);
tasklet_setup(&jme->txclean_task, jme_tx_clean_tasklet);
tasklet_setup(&jme->rxclean_task, jme_rx_clean_tasklet);
tasklet_setup(&jme->rxempty_task, jme_rx_empty_tasklet);
@@ -1920,7 +1919,7 @@ jme_close(struct net_device *netdev)
JME_NAPI_DISABLE(jme);
- tasklet_kill(&jme->linkch_task);
+ cancel_work_sync(&jme->linkch_task);
tasklet_kill(&jme->txclean_task);
tasklet_kill(&jme->rxclean_task);
tasklet_kill(&jme->rxempty_task);
@@ -3039,6 +3038,7 @@ jme_init_one(struct pci_dev *pdev,
atomic_set(&jme->rx_empty, 1);
tasklet_setup(&jme->pcc_task, jme_pcc_tasklet);
+ INIT_WORK(&jme->linkch_task, jme_link_change_work);
jme->dpi.cur = PCC_P1;
jme->reg_ghc = 0;
diff --git a/drivers/net/ethernet/jme.h b/drivers/net/ethernet/jme.h
index a2c3b00d9..2af76329b 100644
--- a/drivers/net/ethernet/jme.h
+++ b/drivers/net/ethernet/jme.h
@@ -411,7 +411,7 @@ struct jme_adapter {
struct tasklet_struct rxempty_task;
struct tasklet_struct rxclean_task;
struct tasklet_struct txclean_task;
- struct tasklet_struct linkch_task;
+ struct work_struct linkch_task;
struct tasklet_struct pcc_task;
unsigned long flags;
u32 reg_txcs;
diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c
index 71e2ada86..72e2e71aa 100644
--- a/drivers/net/wireless/ath/ath9k/beacon.c
+++ b/drivers/net/wireless/ath/ath9k/beacon.c
@@ -251,7 +251,7 @@ void ath9k_beacon_ensure_primary_slot(struct ath_softc *sc)
int first_slot = ATH_BCBUF;
int slot;
- tasklet_disable(&sc->bcon_tasklet);
+ tasklet_disable_in_atomic(&sc->bcon_tasklet);
/* Find first taken slot. */
for (slot = 0; slot < ATH_BCBUF; slot++) {
diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
index 2d6c77dcc..7daba964f 100644
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c
@@ -1518,7 +1518,7 @@ static void hv_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
* Prevents hv_pci_onchannelcallback() from running concurrently
* in the tasklet.
*/
- tasklet_disable(&channel->callback_event);
+ tasklet_disable_in_atomic(&channel->callback_event);
/*
* Since this function is called with IRQ locks held, can't
diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c
index 30afcbbe1..4ae5b8152 100644
--- a/drivers/scsi/fcoe/fcoe.c
+++ b/drivers/scsi/fcoe/fcoe.c
@@ -1452,11 +1452,11 @@ err2:
static int fcoe_alloc_paged_crc_eof(struct sk_buff *skb, int tlen)
{
struct fcoe_percpu_s *fps;
- int rc;
+ int rc, cpu = get_cpu_light();
- fps = &get_cpu_var(fcoe_percpu);
+ fps = &per_cpu(fcoe_percpu, cpu);
rc = fcoe_get_paged_crc_eof(skb, tlen, fps);
- put_cpu_var(fcoe_percpu);
+ put_cpu_light();
return rc;
}
@@ -1641,11 +1641,11 @@ static inline int fcoe_filter_frames(struct fc_lport *lport,
return 0;
}
- stats = per_cpu_ptr(lport->stats, get_cpu());
+ stats = per_cpu_ptr(lport->stats, get_cpu_light());
stats->InvalidCRCCount++;
if (stats->InvalidCRCCount < 5)
printk(KERN_WARNING "fcoe: dropping frame with CRC error\n");
- put_cpu();
+ put_cpu_light();
return -EINVAL;
}
@@ -1686,7 +1686,7 @@ static void fcoe_recv_frame(struct sk_buff *skb)
*/
hp = (struct fcoe_hdr *) skb_network_header(skb);
- stats = per_cpu_ptr(lport->stats, get_cpu());
+ stats = per_cpu_ptr(lport->stats, get_cpu_light());
if (unlikely(FC_FCOE_DECAPS_VER(hp) != FC_FCOE_VER)) {
if (stats->ErrorFrames < 5)
printk(KERN_WARNING "fcoe: FCoE version "
@@ -1718,13 +1718,13 @@ static void fcoe_recv_frame(struct sk_buff *skb)
goto drop;
if (!fcoe_filter_frames(lport, fp)) {
- put_cpu();
+ put_cpu_light();
fc_exch_recv(lport, fp);
return;
}
drop:
stats->ErrorFrames++;
- put_cpu();
+ put_cpu_light();
kfree_skb(skb);
}
diff --git a/drivers/scsi/fcoe/fcoe_ctlr.c b/drivers/scsi/fcoe/fcoe_ctlr.c
index 5ea426eff..0d6b9acc7 100644
--- a/drivers/scsi/fcoe/fcoe_ctlr.c
+++ b/drivers/scsi/fcoe/fcoe_ctlr.c
@@ -828,7 +828,7 @@ static unsigned long fcoe_ctlr_age_fcfs(struct fcoe_ctlr *fip)
INIT_LIST_HEAD(&del_list);
- stats = per_cpu_ptr(fip->lp->stats, get_cpu());
+ stats = per_cpu_ptr(fip->lp->stats, get_cpu_light());
list_for_each_entry_safe(fcf, next, &fip->fcfs, list) {
deadline = fcf->time + fcf->fka_period + fcf->fka_period / 2;
@@ -864,7 +864,7 @@ static unsigned long fcoe_ctlr_age_fcfs(struct fcoe_ctlr *fip)
sel_time = fcf->time;
}
}
- put_cpu();
+ put_cpu_light();
list_for_each_entry_safe(fcf, next, &del_list, list) {
/* Removes fcf from current list */
diff --git a/drivers/scsi/libfc/fc_exch.c b/drivers/scsi/libfc/fc_exch.c
index 4261380af..65160eaaa 100644
--- a/drivers/scsi/libfc/fc_exch.c
+++ b/drivers/scsi/libfc/fc_exch.c
@@ -826,10 +826,10 @@ static struct fc_exch *fc_exch_em_alloc(struct fc_lport *lport,
}
memset(ep, 0, sizeof(*ep));
- cpu = get_cpu();
+ cpu = get_cpu_light();
pool = per_cpu_ptr(mp->pool, cpu);
spin_lock_bh(&pool->lock);
- put_cpu();
+ put_cpu_light();
/* peek cache of free slot */
if (pool->left != FC_XID_UNKNOWN) {
diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h
index 61b11490a..32c534b87 100644
--- a/drivers/tty/serial/8250/8250.h
+++ b/drivers/tty/serial/8250/8250.h
@@ -152,12 +152,55 @@ static inline void serial_dl_write(struct uart_8250_port *up, int value)
up->dl_write(up, value);
}
+static inline void serial8250_set_IER(struct uart_8250_port *up,
+ unsigned char ier)
+{
+ struct uart_port *port = &up->port;
+ unsigned int flags;
+ bool is_console;
+
+ is_console = uart_console(port);
+
+ if (is_console)
+ console_atomic_lock(&flags);
+
+ serial_out(up, UART_IER, ier);
+
+ if (is_console)
+ console_atomic_unlock(flags);
+}
+
+static inline unsigned char serial8250_clear_IER(struct uart_8250_port *up)
+{
+ struct uart_port *port = &up->port;
+ unsigned int clearval = 0;
+ unsigned int prior;
+ unsigned int flags;
+ bool is_console;
+
+ is_console = uart_console(port);
+
+ if (up->capabilities & UART_CAP_UUE)
+ clearval = UART_IER_UUE;
+
+ if (is_console)
+ console_atomic_lock(&flags);
+
+ prior = serial_port_in(port, UART_IER);
+ serial_port_out(port, UART_IER, clearval);
+
+ if (is_console)
+ console_atomic_unlock(flags);
+
+ return prior;
+}
+
static inline bool serial8250_set_THRI(struct uart_8250_port *up)
{
if (up->ier & UART_IER_THRI)
return false;
up->ier |= UART_IER_THRI;
- serial_out(up, UART_IER, up->ier);
+ serial8250_set_IER(up, up->ier);
return true;
}
@@ -166,7 +209,7 @@ static inline bool serial8250_clear_THRI(struct uart_8250_port *up)
if (!(up->ier & UART_IER_THRI))
return false;
up->ier &= ~UART_IER_THRI;
- serial_out(up, UART_IER, up->ier);
+ serial8250_set_IER(up, up->ier);
return true;
}
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 355ee338d..5c1bb9e06 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -275,10 +275,8 @@ static void serial8250_backup_timeout(struct timer_list *t)
* Must disable interrupts or else we risk racing with the interrupt
* based handler.
*/
- if (up->port.irq) {
- ier = serial_in(up, UART_IER);
- serial_out(up, UART_IER, 0);
- }
+ if (up->port.irq)
+ ier = serial8250_clear_IER(up);
iir = serial_in(up, UART_IIR);
@@ -301,7 +299,7 @@ static void serial8250_backup_timeout(struct timer_list *t)
serial8250_tx_chars(up);
if (up->port.irq)
- serial_out(up, UART_IER, ier);
+ serial8250_set_IER(up, ier);
spin_unlock_irqrestore(&up->port.lock, flags);
@@ -588,6 +586,14 @@ serial8250_register_ports(struct uart_driver *drv, struct device *dev)
#ifdef CONFIG_SERIAL_8250_CONSOLE
+static void univ8250_console_write_atomic(struct console *co, const char *s,
+ unsigned int count)
+{
+ struct uart_8250_port *up = &serial8250_ports[co->index];
+
+ serial8250_console_write_atomic(up, s, count);
+}
+
static void univ8250_console_write(struct console *co, const char *s,
unsigned int count)
{
@@ -681,6 +687,7 @@ static int univ8250_console_match(struct console *co, char *name, int idx,
static struct console univ8250_console = {
.name = "ttyS",
+ .write_atomic = univ8250_console_write_atomic,
.write = univ8250_console_write,
.device = uart_console_device,
.setup = univ8250_console_setup,
diff --git a/drivers/tty/serial/8250/8250_fsl.c b/drivers/tty/serial/8250/8250_fsl.c
index fbcc90c31..b33cb454c 100644
--- a/drivers/tty/serial/8250/8250_fsl.c
+++ b/drivers/tty/serial/8250/8250_fsl.c
@@ -60,9 +60,18 @@ int fsl8250_handle_irq(struct uart_port *port)
/* Stop processing interrupts on input overrun */
if ((orig_lsr & UART_LSR_OE) && (up->overrun_backoff_time_ms > 0)) {
+ unsigned int ca_flags;
unsigned long delay;
+ bool is_console;
+ is_console = uart_console(port);
+
+ if (is_console)
+ console_atomic_lock(&ca_flags);
up->ier = port->serial_in(port, UART_IER);
+ if (is_console)
+ console_atomic_unlock(ca_flags);
+
if (up->ier & (UART_IER_RLSI | UART_IER_RDI)) {
port->ops->stop_rx(port);
} else {
diff --git a/drivers/tty/serial/8250/8250_ingenic.c b/drivers/tty/serial/8250/8250_ingenic.c
index 988bf6bcc..bcd26d672 100644
--- a/drivers/tty/serial/8250/8250_ingenic.c
+++ b/drivers/tty/serial/8250/8250_ingenic.c
@@ -146,6 +146,8 @@ OF_EARLYCON_DECLARE(x1000_uart, "ingenic,x1000-uart",
static void ingenic_uart_serial_out(struct uart_port *p, int offset, int value)
{
+ unsigned int flags;
+ bool is_console;
int ier;
switch (offset) {
@@ -167,7 +169,12 @@ static void ingenic_uart_serial_out(struct uart_port *p, int offset, int value)
* If we have enabled modem status IRQs we should enable
* modem mode.
*/
+ is_console = uart_console(p);
+ if (is_console)
+ console_atomic_lock(&flags);
ier = p->serial_in(p, UART_IER);
+ if (is_console)
+ console_atomic_unlock(flags);
if (ier & UART_IER_MSI)
value |= UART_MCR_MDCE | UART_MCR_FCM;
diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c
index de48a5846..d246f2755 100644
--- a/drivers/tty/serial/8250/8250_mtk.c
+++ b/drivers/tty/serial/8250/8250_mtk.c
@@ -222,12 +222,37 @@ static void mtk8250_shutdown(struct uart_port *port)
static void mtk8250_disable_intrs(struct uart_8250_port *up, int mask)
{
- serial_out(up, UART_IER, serial_in(up, UART_IER) & (~mask));
+ struct uart_port *port = &up->port;
+ unsigned int flags;
+ unsigned int ier;
+ bool is_console;
+
+ is_console = uart_console(port);
+
+ if (is_console)
+ console_atomic_lock(&flags);
+
+ ier = serial_in(up, UART_IER);
+ serial_out(up, UART_IER, ier & (~mask));
+
+ if (is_console)
+ console_atomic_unlock(flags);
}
static void mtk8250_enable_intrs(struct uart_8250_port *up, int mask)
{
- serial_out(up, UART_IER, serial_in(up, UART_IER) | mask);
+ struct uart_port *port = &up->port;
+ unsigned int flags;
+ unsigned int ier;
+
+ if (uart_console(port))
+ console_atomic_lock(&flags);
+
+ ier = serial_in(up, UART_IER);
+ serial_out(up, UART_IER, ier | mask);
+
+ if (uart_console(port))
+ console_atomic_unlock(flags);
}
static void mtk8250_set_flow_ctrl(struct uart_8250_port *up, int mode)
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 6098e87a3..8eee07321 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -730,7 +730,7 @@ static void serial8250_set_sleep(struct uart_8250_port *p, int sleep)
serial_out(p, UART_EFR, UART_EFR_ECB);
serial_out(p, UART_LCR, 0);
}
- serial_out(p, UART_IER, sleep ? UART_IERX_SLEEP : 0);
+ serial8250_set_IER(p, sleep ? UART_IERX_SLEEP : 0);
if (p->capabilities & UART_CAP_EFR) {
serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B);
serial_out(p, UART_EFR, efr);
@@ -1399,7 +1399,7 @@ static void serial8250_stop_rx(struct uart_port *port)
up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
up->port.read_status_mask &= ~UART_LSR_DR;
- serial_port_out(port, UART_IER, up->ier);
+ serial8250_set_IER(up, up->ier);
serial8250_rpm_put(up);
}
@@ -1429,7 +1429,7 @@ void serial8250_em485_stop_tx(struct uart_8250_port *p)
serial8250_clear_and_reinit_fifos(p);
p->ier |= UART_IER_RLSI | UART_IER_RDI;
- serial_port_out(&p->port, UART_IER, p->ier);
+ serial8250_set_IER(p, p->ier);
}
}
EXPORT_SYMBOL_GPL(serial8250_em485_stop_tx);
@@ -1671,7 +1671,7 @@ static void serial8250_disable_ms(struct uart_port *port)
mctrl_gpio_disable_ms(up->gpios);
up->ier &= ~UART_IER_MSI;
- serial_port_out(port, UART_IER, up->ier);
+ serial8250_set_IER(up, up->ier);
}
static void serial8250_enable_ms(struct uart_port *port)
@@ -1687,7 +1687,7 @@ static void serial8250_enable_ms(struct uart_port *port)
up->ier |= UART_IER_MSI;
serial8250_rpm_get(up);
- serial_port_out(port, UART_IER, up->ier);
+ serial8250_set_IER(up, up->ier);
serial8250_rpm_put(up);
}
@@ -2123,14 +2123,7 @@ static void serial8250_put_poll_char(struct uart_port *port,
struct uart_8250_port *up = up_to_u8250p(port);
serial8250_rpm_get(up);
- /*
- * First save the IER then disable the interrupts
- */
- ier = serial_port_in(port, UART_IER);
- if (up->capabilities & UART_CAP_UUE)
- serial_port_out(port, UART_IER, UART_IER_UUE);
- else
- serial_port_out(port, UART_IER, 0);
+ ier = serial8250_clear_IER(up);
wait_for_xmitr(up, BOTH_EMPTY);
/*
@@ -2143,7 +2136,7 @@ static void serial8250_put_poll_char(struct uart_port *port,
* and restore the IER
*/
wait_for_xmitr(up, BOTH_EMPTY);
- serial_port_out(port, UART_IER, ier);
+ serial8250_set_IER(up, ier);
serial8250_rpm_put(up);
}
@@ -2448,7 +2441,7 @@ void serial8250_do_shutdown(struct uart_port *port)
*/
spin_lock_irqsave(&port->lock, flags);
up->ier = 0;
- serial_port_out(port, UART_IER, 0);
+ serial8250_set_IER(up, 0);
spin_unlock_irqrestore(&port->lock, flags);
synchronize_irq(port->irq);
@@ -2800,7 +2793,7 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,
if (up->capabilities & UART_CAP_RTOIE)
up->ier |= UART_IER_RTOIE;
- serial_port_out(port, UART_IER, up->ier);
+ serial8250_set_IER(up, up->ier);
if (up->capabilities & UART_CAP_EFR) {
unsigned char efr = 0;
@@ -3265,7 +3258,7 @@ EXPORT_SYMBOL_GPL(serial8250_set_defaults);
#ifdef CONFIG_SERIAL_8250_CONSOLE
-static void serial8250_console_putchar(struct uart_port *port, int ch)
+static void serial8250_console_putchar_locked(struct uart_port *port, int ch)
{
struct uart_8250_port *up = up_to_u8250p(port);
@@ -3273,6 +3266,18 @@ static void serial8250_console_putchar(struct uart_port *port, int ch)
serial_port_out(port, UART_TX, ch);
}
+static void serial8250_console_putchar(struct uart_port *port, int ch)
+{
+ struct uart_8250_port *up = up_to_u8250p(port);
+ unsigned int flags;
+
+ wait_for_xmitr(up, UART_LSR_THRE);
+
+ console_atomic_lock(&flags);
+ serial8250_console_putchar_locked(port, ch);
+ console_atomic_unlock(flags);
+}
+
/*
* Restore serial console when h/w power-off detected
*/
@@ -3299,6 +3304,32 @@ static void serial8250_console_restore(struct uart_8250_port *up)
serial8250_out_MCR(up, up->mcr | UART_MCR_DTR | UART_MCR_RTS);
}
+void serial8250_console_write_atomic(struct uart_8250_port *up,
+ const char *s, unsigned int count)
+{
+ struct uart_port *port = &up->port;
+ unsigned int flags;
+ unsigned int ier;
+
+ console_atomic_lock(&flags);
+
+ touch_nmi_watchdog();
+
+ ier = serial8250_clear_IER(up);
+
+ if (atomic_fetch_inc(&up->console_printing)) {
+ uart_console_write(port, "\n", 1,
+ serial8250_console_putchar_locked);
+ }
+ uart_console_write(port, s, count, serial8250_console_putchar_locked);
+ atomic_dec(&up->console_printing);
+
+ wait_for_xmitr(up, BOTH_EMPTY);
+ serial8250_set_IER(up, ier);
+
+ console_atomic_unlock(flags);
+}
+
/*
* Print a string to the serial port trying not to disturb
* any possible real use of the port...
@@ -3315,24 +3346,12 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
struct uart_port *port = &up->port;
unsigned long flags;
unsigned int ier;
- int locked = 1;
touch_nmi_watchdog();
- if (oops_in_progress)
- locked = spin_trylock_irqsave(&port->lock, flags);
- else
- spin_lock_irqsave(&port->lock, flags);
-
- /*
- * First save the IER then disable the interrupts
- */
- ier = serial_port_in(port, UART_IER);
+ spin_lock_irqsave(&port->lock, flags);
- if (up->capabilities & UART_CAP_UUE)
- serial_port_out(port, UART_IER, UART_IER_UUE);
- else
- serial_port_out(port, UART_IER, 0);
+ ier = serial8250_clear_IER(up);
/* check scratch reg to see if port powered off during system sleep */
if (up->canary && (up->canary != serial_port_in(port, UART_SCR))) {
@@ -3346,7 +3365,9 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
mdelay(port->rs485.delay_rts_before_send);
}
+ atomic_inc(&up->console_printing);
uart_console_write(port, s, count, serial8250_console_putchar);
+ atomic_dec(&up->console_printing);
/*
* Finally, wait for transmitter to become empty
@@ -3359,8 +3380,7 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
if (em485->tx_stopped)
up->rs485_stop_tx(up);
}
-
- serial_port_out(port, UART_IER, ier);
+ serial8250_set_IER(up, ier);
/*
* The receive handling will happen properly because the
@@ -3372,8 +3392,7 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
if (up->msr_saved_flags)
serial8250_modem_status(up);
- if (locked)
- spin_unlock_irqrestore(&port->lock, flags);
+ spin_unlock_irqrestore(&port->lock, flags);
}
static unsigned int probe_baud(struct uart_port *port)
@@ -3393,6 +3412,7 @@ static unsigned int probe_baud(struct uart_port *port)
int serial8250_console_setup(struct uart_port *port, char *options, bool probe)
{
+ struct uart_8250_port *up = up_to_u8250p(port);
int baud = 9600;
int bits = 8;
int parity = 'n';
@@ -3402,6 +3422,8 @@ int serial8250_console_setup(struct uart_port *port, char *options, bool probe)
if (!port->iobase && !port->membase)
return -ENODEV;
+ atomic_set(&up->console_printing, 0);
+
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else if (probe)
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 638255a0e..7b61bd709 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -2276,18 +2276,24 @@ pl011_console_write(struct console *co, const char *s, unsigned int count)
{
struct uart_amba_port *uap = amba_ports[co->index];
unsigned int old_cr = 0, new_cr;
- unsigned long flags;
+ unsigned long flags = 0;
int locked = 1;
clk_enable(uap->clk);
- local_irq_save(flags);
+ /*
+ * local_irq_save(flags);
+ *
+ * This local_irq_save() is nonsense. If we come in via sysrq
+ * handling then interrupts are already disabled. Aside of
+ * that the port.sysrq check is racy on SMP regardless.
+ */
if (uap->port.sysrq)
locked = 0;
else if (oops_in_progress)
- locked = spin_trylock(&uap->port.lock);
+ locked = spin_trylock_irqsave(&uap->port.lock, flags);
else
- spin_lock(&uap->port.lock);
+ spin_lock_irqsave(&uap->port.lock, flags);
/*
* First save the CR then disable the interrupts
@@ -2313,8 +2319,7 @@ pl011_console_write(struct console *co, const char *s, unsigned int count)
pl011_write(old_cr, uap, REG_CR);
if (locked)
- spin_unlock(&uap->port.lock);
- local_irq_restore(flags);
+ spin_unlock_irqrestore(&uap->port.lock, flags);
clk_disable(uap->clk);
}
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 84e815808..342005ed5 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -1311,13 +1311,10 @@ serial_omap_console_write(struct console *co, const char *s,
pm_runtime_get_sync(up->dev);
- local_irq_save(flags);
- if (up->port.sysrq)
- locked = 0;
- else if (oops_in_progress)
- locked = spin_trylock(&up->port.lock);
+ if (up->port.sysrq || oops_in_progress)
+ locked = spin_trylock_irqsave(&up->port.lock, flags);
else
- spin_lock(&up->port.lock);
+ spin_lock_irqsave(&up->port.lock, flags);
/*
* First save the IER then disable the interrupts
@@ -1346,8 +1343,7 @@ serial_omap_console_write(struct console *co, const char *s,
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
if (locked)
- spin_unlock(&up->port.lock);
- local_irq_restore(flags);
+ spin_unlock_irqrestore(&up->port.lock, flags);
}
static int __init
diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c
index 89e3e220f..30e549b5e 100644
--- a/drivers/tty/tty_buffer.c
+++ b/drivers/tty/tty_buffer.c
@@ -172,10 +172,10 @@ static struct tty_buffer *tty_buffer_alloc(struct tty_port *port, size_t size)
have queued and recycle that ? */
if (atomic_read(&port->buf.mem_used) > port->buf.mem_limit)
return NULL;
- printk_safe_enter();
+
p = kmalloc(sizeof(struct tty_buffer) + 2 * size,
GFP_ATOMIC | __GFP_NOWARN);
- printk_safe_exit();
+
if (p == NULL)
return NULL;
diff --git a/fs/afs/dir_silly.c b/fs/afs/dir_silly.c
index dae9a57d7..9a6a0ec4d 100644
--- a/fs/afs/dir_silly.c
+++ b/fs/afs/dir_silly.c
@@ -239,7 +239,7 @@ int afs_silly_iput(struct dentry *dentry, struct inode *inode)
struct dentry *alias;
int ret;
- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
_enter("%p{%pd},%llx", dentry, dentry, vnode->fid.vnode);
diff --git a/fs/aio.c b/fs/aio.c
index 78aaeaf35..d3229b5ca 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -43,7 +43,6 @@
#include <linux/mount.h>
#include <linux/pseudo_fs.h>
-#include <asm/kmap_types.h>
#include <linux/uaccess.h>
#include <linux/nospec.h>
@@ -1777,7 +1776,7 @@ static int aio_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
list_del_init(&req->wait.entry);
list_del(&iocb->ki_list);
iocb->ki_res.res = mangle_poll(mask);
- if (iocb->ki_eventfd && eventfd_signal_count()) {
+ if (iocb->ki_eventfd && !eventfd_signal_allowed()) {
iocb = NULL;
INIT_WORK(&req->work, aio_poll_put_work);
schedule_work(&req->work);
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index abc1e72a4..82b3b7523 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -17,7 +17,6 @@
#include <linux/wait.h>
#include <linux/slab.h>
#include <trace/events/btrfs.h>
-#include <asm/kmap_types.h>
#include <asm/unaligned.h>
#include <linux/pagemap.h>
#include <linux/btrfs.h>
diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c
index 799be3a5d..d5165a7da 100644
--- a/fs/cifs/readdir.c
+++ b/fs/cifs/readdir.c
@@ -81,7 +81,7 @@ cifs_prime_dcache(struct dentry *parent, struct qstr *name,
struct inode *inode;
struct super_block *sb = parent->d_sb;
struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
cifs_dbg(FYI, "%s: for %s\n", __func__, name->name);
diff --git a/fs/dcache.c b/fs/dcache.c
index 5dccce5bc..12a576121 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -2597,9 +2597,10 @@ EXPORT_SYMBOL(d_rehash);
static inline unsigned start_dir_add(struct inode *dir)
{
+ preempt_disable_rt();
for (;;) {
- unsigned n = dir->i_dir_seq;
- if (!(n & 1) && cmpxchg(&dir->i_dir_seq, n, n + 1) == n)
+ unsigned n = dir->__i_dir_seq;
+ if (!(n & 1) && cmpxchg(&dir->__i_dir_seq, n, n + 1) == n)
return n;
cpu_relax();
}
@@ -2607,26 +2608,30 @@ static inline unsigned start_dir_add(struct inode *dir)
static inline void end_dir_add(struct inode *dir, unsigned n)
{
- smp_store_release(&dir->i_dir_seq, n + 2);
+ smp_store_release(&dir->__i_dir_seq, n + 2);
+ preempt_enable_rt();
}
static void d_wait_lookup(struct dentry *dentry)
{
- if (d_in_lookup(dentry)) {
- DECLARE_WAITQUEUE(wait, current);
- add_wait_queue(dentry->d_wait, &wait);
- do {
- set_current_state(TASK_UNINTERRUPTIBLE);
- spin_unlock(&dentry->d_lock);
- schedule();
- spin_lock(&dentry->d_lock);
- } while (d_in_lookup(dentry));
- }
+ struct swait_queue __wait;
+
+ if (!d_in_lookup(dentry))
+ return;
+
+ INIT_LIST_HEAD(&__wait.task_list);
+ do {
+ prepare_to_swait_exclusive(dentry->d_wait, &__wait, TASK_UNINTERRUPTIBLE);
+ spin_unlock(&dentry->d_lock);
+ schedule();
+ spin_lock(&dentry->d_lock);
+ } while (d_in_lookup(dentry));
+ finish_swait(dentry->d_wait, &__wait);
}
struct dentry *d_alloc_parallel(struct dentry *parent,
const struct qstr *name,
- wait_queue_head_t *wq)
+ struct swait_queue_head *wq)
{
unsigned int hash = name->hash;
struct hlist_bl_head *b = in_lookup_hash(parent, hash);
@@ -2640,7 +2645,7 @@ struct dentry *d_alloc_parallel(struct dentry *parent,
retry:
rcu_read_lock();
- seq = smp_load_acquire(&parent->d_inode->i_dir_seq);
+ seq = smp_load_acquire(&parent->d_inode->__i_dir_seq);
r_seq = read_seqbegin(&rename_lock);
dentry = __d_lookup_rcu(parent, name, &d_seq);
if (unlikely(dentry)) {
@@ -2668,7 +2673,7 @@ retry:
}
hlist_bl_lock(b);
- if (unlikely(READ_ONCE(parent->d_inode->i_dir_seq) != seq)) {
+ if (unlikely(READ_ONCE(parent->d_inode->__i_dir_seq) != seq)) {
hlist_bl_unlock(b);
rcu_read_unlock();
goto retry;
@@ -2741,7 +2746,7 @@ void __d_lookup_done(struct dentry *dentry)
hlist_bl_lock(b);
dentry->d_flags &= ~DCACHE_PAR_LOOKUP;
__hlist_bl_del(&dentry->d_u.d_in_lookup_hash);
- wake_up_all(dentry->d_wait);
+ swake_up_all(dentry->d_wait);
dentry->d_wait = NULL;
hlist_bl_unlock(b);
INIT_HLIST_NODE(&dentry->d_u.d_alias);
diff --git a/fs/eventfd.c b/fs/eventfd.c
index 3673eb8de..5ff8cc554 100644
--- a/fs/eventfd.c
+++ b/fs/eventfd.c
@@ -25,8 +25,6 @@
#include <linux/idr.h>
#include <linux/uio.h>
-DEFINE_PER_CPU(int, eventfd_wake_count);
-
static DEFINE_IDA(eventfd_ida);
struct eventfd_ctx {
@@ -57,17 +55,17 @@ __u64 eventfd_signal_mask(struct eventfd_ctx *ctx, __u64 n, unsigned mask)
* it returns true, the eventfd_signal() call should be deferred to a
* safe context.
*/
- if (WARN_ON_ONCE(this_cpu_read(eventfd_wake_count)))
+ if (WARN_ON_ONCE(current->in_eventfd_signal))
return 0;
spin_lock_irqsave(&ctx->wqh.lock, flags);
- this_cpu_inc(eventfd_wake_count);
+ current->in_eventfd_signal = 1;
if (ULLONG_MAX - ctx->count < n)
n = ULLONG_MAX - ctx->count;
ctx->count += n;
if (waitqueue_active(&ctx->wqh))
wake_up_locked_poll(&ctx->wqh, EPOLLIN | mask);
- this_cpu_dec(eventfd_wake_count);
+ current->in_eventfd_signal = 0;
spin_unlock_irqrestore(&ctx->wqh.lock, flags);
return n;
diff --git a/fs/fscache/internal.h b/fs/fscache/internal.h
index 64aa552b2..7dae569da 100644
--- a/fs/fscache/internal.h
+++ b/fs/fscache/internal.h
@@ -95,7 +95,6 @@ extern unsigned fscache_debug;
extern struct kobject *fscache_root;
extern struct workqueue_struct *fscache_object_wq;
extern struct workqueue_struct *fscache_op_wq;
-DECLARE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait);
extern unsigned int fscache_hash(unsigned int salt, unsigned int *data, unsigned int n);
diff --git a/fs/fscache/main.c b/fs/fscache/main.c
index 4207f98e4..85f8cf3a3 100644
--- a/fs/fscache/main.c
+++ b/fs/fscache/main.c
@@ -41,8 +41,6 @@ struct kobject *fscache_root;
struct workqueue_struct *fscache_object_wq;
struct workqueue_struct *fscache_op_wq;
-DEFINE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait);
-
/* these values serve as lower bounds, will be adjusted in fscache_init() */
static unsigned fscache_object_max_active = 4;
static unsigned fscache_op_max_active = 2;
@@ -138,7 +136,6 @@ unsigned int fscache_hash(unsigned int salt, unsigned int *data, unsigned int n)
static int __init fscache_init(void)
{
unsigned int nr_cpus = num_possible_cpus();
- unsigned int cpu;
int ret;
fscache_object_max_active =
@@ -161,9 +158,6 @@ static int __init fscache_init(void)
if (!fscache_op_wq)
goto error_op_wq;
- for_each_possible_cpu(cpu)
- init_waitqueue_head(&per_cpu(fscache_object_cong_wait, cpu));
-
ret = fscache_proc_init();
if (ret < 0)
goto error_proc;
diff --git a/fs/fscache/object.c b/fs/fscache/object.c
index cb2146e02..fb9794dce 100644
--- a/fs/fscache/object.c
+++ b/fs/fscache/object.c
@@ -807,6 +807,8 @@ void fscache_object_destroy(struct fscache_object *object)
}
EXPORT_SYMBOL(fscache_object_destroy);
+static DECLARE_WAIT_QUEUE_HEAD(fscache_object_cong_wait);
+
/*
* enqueue an object for metadata-type processing
*/
@@ -815,16 +817,12 @@ void fscache_enqueue_object(struct fscache_object *object)
_enter("{OBJ%x}", object->debug_id);
if (fscache_get_object(object, fscache_obj_get_queue) >= 0) {
- wait_queue_head_t *cong_wq =
- &get_cpu_var(fscache_object_cong_wait);
if (queue_work(fscache_object_wq, &object->work)) {
if (fscache_object_congested())
- wake_up(cong_wq);
+ wake_up(&fscache_object_cong_wait);
} else
fscache_put_object(object, fscache_obj_put_queue);
-
- put_cpu_var(fscache_object_cong_wait);
}
}
@@ -842,16 +840,15 @@ void fscache_enqueue_object(struct fscache_object *object)
*/
bool fscache_object_sleep_till_congested(signed long *timeoutp)
{
- wait_queue_head_t *cong_wq = this_cpu_ptr(&fscache_object_cong_wait);
DEFINE_WAIT(wait);
if (fscache_object_congested())
return true;
- add_wait_queue_exclusive(cong_wq, &wait);
+ add_wait_queue_exclusive(&fscache_object_cong_wait, &wait);
if (!fscache_object_congested())
*timeoutp = schedule_timeout(*timeoutp);
- finish_wait(cong_wq, &wait);
+ finish_wait(&fscache_object_cong_wait, &wait);
return fscache_object_congested();
}
diff --git a/fs/fuse/readdir.c b/fs/fuse/readdir.c
index 14e99ffa5..eb899feaf 100644
--- a/fs/fuse/readdir.c
+++ b/fs/fuse/readdir.c
@@ -160,7 +160,7 @@ static int fuse_direntplus_link(struct file *file,
struct inode *dir = d_inode(parent);
struct fuse_conn *fc;
struct inode *inode;
- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
if (!o->nodeid) {
/*
diff --git a/fs/inode.c b/fs/inode.c
index 6bec245f9..65582767a 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -158,7 +158,7 @@ int inode_init_always(struct super_block *sb, struct inode *inode)
inode->i_bdev = NULL;
inode->i_cdev = NULL;
inode->i_link = NULL;
- inode->i_dir_seq = 0;
+ inode->__i_dir_seq = 0;
inode->i_rdev = 0;
inode->dirtied_when = 0;
diff --git a/fs/namei.c b/fs/namei.c
index 3588e12d6..7a171441c 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1538,7 +1538,7 @@ static struct dentry *__lookup_slow(const struct qstr *name,
{
struct dentry *dentry, *old;
struct inode *inode = dir->d_inode;
- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
/* Don't go there if it's already dead */
if (unlikely(IS_DEADDIR(inode)))
@@ -3092,7 +3092,7 @@ static struct dentry *lookup_open(struct nameidata *nd, struct file *file,
struct dentry *dentry;
int error, create_error = 0;
umode_t mode = op->mode;
- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
if (unlikely(IS_DEADDIR(dir_inode)))
return ERR_PTR(-ENOENT);
diff --git a/fs/namespace.c b/fs/namespace.c
index 61c88343c..4750c6fc5 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -14,6 +14,7 @@
#include <linux/mnt_namespace.h>
#include <linux/user_namespace.h>
#include <linux/namei.h>
+#include <linux/delay.h>
#include <linux/security.h>
#include <linux/cred.h>
#include <linux/idr.h>
@@ -322,8 +323,11 @@ int __mnt_want_write(struct vfsmount *m)
* incremented count after it has set MNT_WRITE_HOLD.
*/
smp_mb();
- while (READ_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD)
- cpu_relax();
+ while (READ_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD) {
+ preempt_enable();
+ cpu_chill();
+ preempt_disable();
+ }
/*
* After the slowpath clears MNT_WRITE_HOLD, mnt_is_readonly will
* be set to match its requirements. So we must not load that until
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 9f88ca7b2..bc8a78ecf 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -484,7 +484,7 @@ void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry,
unsigned long dir_verifier)
{
struct qstr filename = QSTR_INIT(entry->name, entry->len);
- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
struct dentry *dentry;
struct dentry *alias;
struct inode *inode;
@@ -1660,7 +1660,7 @@ int nfs_atomic_open(struct inode *dir, struct dentry *dentry,
struct file *file, unsigned open_flags,
umode_t mode)
{
- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
struct nfs_open_context *ctx;
struct dentry *res;
struct iattr attr = { .ia_valid = ATTR_OPEN };
diff --git a/fs/nfs/unlink.c b/fs/nfs/unlink.c
index b27ebdcce..f86c98a7e 100644
--- a/fs/nfs/unlink.c
+++ b/fs/nfs/unlink.c
@@ -13,7 +13,7 @@
#include <linux/sunrpc/clnt.h>
#include <linux/nfs_fs.h>
#include <linux/sched.h>
-#include <linux/wait.h>
+#include <linux/swait.h>
#include <linux/namei.h>
#include <linux/fsnotify.h>
@@ -180,7 +180,7 @@ nfs_async_unlink(struct dentry *dentry, const struct qstr *name)
data->cred = get_current_cred();
data->res.dir_attr = &data->dir_attr;
- init_waitqueue_head(&data->wq);
+ init_swait_queue_head(&data->wq);
status = -EBUSY;
spin_lock(&dentry->d_lock);
diff --git a/fs/proc/array.c b/fs/proc/array.c
index d5fed9281..74629a413 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -384,9 +384,9 @@ static inline void task_context_switch_counts(struct seq_file *m,
static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
{
seq_printf(m, "Cpus_allowed:\t%*pb\n",
- cpumask_pr_args(task->cpus_ptr));
+ cpumask_pr_args(&task->cpus_mask));
seq_printf(m, "Cpus_allowed_list:\t%*pbl\n",
- cpumask_pr_args(task->cpus_ptr));
+ cpumask_pr_args(&task->cpus_mask));
}
#ifdef CONFIG_QOS_SCHED_DYNAMIC_AFFINITY
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 4e0054a37..2cb62db96 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -106,7 +106,7 @@
#include <trace/events/oom.h>
#include "internal.h"
#include "fd.h"
-
+#include <linux/swait.h>
#include "../../lib/kstrtox.h"
/* NOTE:
@@ -2275,7 +2275,7 @@ bool proc_fill_cache(struct file *file, struct dir_context *ctx,
child = d_hash_and_lookup(dir, &qname);
if (!child) {
- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
child = d_alloc_parallel(dir, &qname, &wq);
if (IS_ERR(child))
goto end_instantiate;
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index d018184a1..10052f549 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -682,7 +682,7 @@ static bool proc_sys_fill_cache(struct file *file,
child = d_lookup(dir, &qname);
if (!child) {
- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
child = d_alloc_parallel(dir, &qname, &wq);
if (IS_ERR(child))
return false;
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index d59f13b1f..64f3f85d2 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -384,7 +384,8 @@ void pstore_record_init(struct pstore_record *record,
* end of the buffer.
*/
static void pstore_dump(struct kmsg_dumper *dumper,
- enum kmsg_dump_reason reason)
+ enum kmsg_dump_reason reason,
+ struct kmsg_dumper_iter *iter)
{
unsigned long total = 0;
const char *why;
@@ -434,7 +435,7 @@ static void pstore_dump(struct kmsg_dumper *dumper,
dst_size -= header_size;
/* Write dump contents. */
- if (!kmsg_dump_get_buffer(dumper, true, dst + header_size,
+ if (!kmsg_dump_get_buffer(iter, true, dst + header_size,
dst_size, &dump_size))
break;
diff --git a/include/asm-generic/Kbuild b/include/asm-generic/Kbuild
index d1300c6e0..267f6dfb8 100644
--- a/include/asm-generic/Kbuild
+++ b/include/asm-generic/Kbuild
@@ -30,7 +30,7 @@ mandatory-y += irq.h
mandatory-y += irq_regs.h
mandatory-y += irq_work.h
mandatory-y += kdebug.h
-mandatory-y += kmap_types.h
+mandatory-y += kmap_size.h
mandatory-y += kprobes.h
mandatory-y += linkage.h
mandatory-y += local.h
diff --git a/include/asm-generic/hardirq.h b/include/asm-generic/hardirq.h
index d14214dfc..7317e8258 100644
--- a/include/asm-generic/hardirq.h
+++ b/include/asm-generic/hardirq.h
@@ -7,9 +7,13 @@
typedef struct {
unsigned int __softirq_pending;
+#ifdef ARCH_WANTS_NMI_IRQSTAT
+ unsigned int __nmi_count;
+#endif
} ____cacheline_aligned irq_cpustat_t;
-#include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
+DECLARE_PER_CPU_ALIGNED(irq_cpustat_t, irq_stat);
+
#include <linux/irq.h>
#ifndef ack_bad_irq
diff --git a/include/asm-generic/kmap_size.h b/include/asm-generic/kmap_size.h
new file mode 100644
index 000000000..9d6c7786a
--- /dev/null
+++ b/include/asm-generic/kmap_size.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_GENERIC_KMAP_SIZE_H
+#define _ASM_GENERIC_KMAP_SIZE_H
+
+/* For debug this provides guard pages between the maps */
+#ifdef CONFIG_DEBUG_HIGHMEM
+# define KM_MAX_IDX 33
+#else
+# define KM_MAX_IDX 16
+#endif
+
+#endif
diff --git a/include/asm-generic/kmap_types.h b/include/asm-generic/kmap_types.h
deleted file mode 100644
index 9f95b7b63..000000000
--- a/include/asm-generic/kmap_types.h
+++ /dev/null
@@ -1,11 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_GENERIC_KMAP_TYPES_H
-#define _ASM_GENERIC_KMAP_TYPES_H
-
-#ifdef __WITH_KM_FENCE
-# define KM_TYPE_NR 41
-#else
-# define KM_TYPE_NR 20
-#endif
-
-#endif
diff --git a/include/asm-generic/preempt.h b/include/asm-generic/preempt.h
index b4d43a4af..ac255e889 100644
--- a/include/asm-generic/preempt.h
+++ b/include/asm-generic/preempt.h
@@ -79,6 +79,9 @@ static __always_inline bool should_resched(int preempt_offset)
}
#ifdef CONFIG_PREEMPTION
+#ifdef CONFIG_PREEMPT_RT
+extern void preempt_schedule_lock(void);
+#endif
extern asmlinkage void preempt_schedule(void);
#define __preempt_schedule() preempt_schedule()
extern asmlinkage void preempt_schedule_notrace(void);
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index f27a0916a..5ee68b9ce 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -166,7 +166,7 @@ struct request {
*/
union {
struct hlist_node hash; /* merge hash */
- struct list_head ipi_list;
+ struct llist_node ipi_list;
};
/*
diff --git a/include/linux/bottom_half.h b/include/linux/bottom_half.h
index a19519f42..eed86eb0a 100644
--- a/include/linux/bottom_half.h
+++ b/include/linux/bottom_half.h
@@ -4,7 +4,7 @@
#include <linux/preempt.h>
-#ifdef CONFIG_TRACE_IRQFLAGS
+#if defined(CONFIG_PREEMPT_RT) || defined(CONFIG_TRACE_IRQFLAGS)
extern void __local_bh_disable_ip(unsigned long ip, unsigned int cnt);
#else
static __always_inline void __local_bh_disable_ip(unsigned long ip, unsigned int cnt)
@@ -32,4 +32,10 @@ static inline void local_bh_enable(void)
__local_bh_enable_ip(_THIS_IP_, SOFTIRQ_DISABLE_OFFSET);
}
+#ifdef CONFIG_PREEMPT_RT
+extern bool local_bh_blocked(void);
+#else
+static inline bool local_bh_blocked(void) { return false; }
+#endif
+
#endif /* _LINUX_BH_H */
diff --git a/include/linux/console.h b/include/linux/console.h
index bc2a749e6..027278792 100644
--- a/include/linux/console.h
+++ b/include/linux/console.h
@@ -16,6 +16,7 @@
#include <linux/atomic.h>
#include <linux/types.h>
+#include <linux/printk.h>
struct vc_data;
struct console_font_op;
@@ -137,10 +138,12 @@ static inline int con_debug_leave(void)
#define CON_ANYTIME (16) /* Safe to call when cpu is offline */
#define CON_BRL (32) /* Used for a braille device */
#define CON_EXTENDED (64) /* Use the extended output format a la /dev/kmsg */
+#define CON_HANDOVER (128) /* Device was previously a boot console. */
struct console {
char name[16];
void (*write)(struct console *, const char *, unsigned);
+ void (*write_atomic)(struct console *co, const char *s, unsigned int count);
int (*read)(struct console *, char *, unsigned);
struct tty_driver *(*device)(struct console *, int *);
void (*unblank)(void);
@@ -150,6 +153,11 @@ struct console {
short flags;
short index;
int cflag;
+#ifdef CONFIG_PRINTK
+ char sync_buf[CONSOLE_LOG_MAX];
+#endif
+ atomic64_t printk_seq;
+ struct task_struct *thread;
uint ispeed;
uint ospeed;
void *data;
@@ -232,4 +240,7 @@ extern void console_init(void);
void dummycon_register_output_notifier(struct notifier_block *nb);
void dummycon_unregister_output_notifier(struct notifier_block *nb);
+extern void console_atomic_lock(unsigned int *flags);
+extern void console_atomic_unlock(unsigned int flags);
+
#endif /* _LINUX_CONSOLE_H */
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index b540e5a60..dacf87c92 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -159,6 +159,7 @@ enum cpuhp_state {
CPUHP_AP_ONLINE,
CPUHP_TEARDOWN_CPU,
CPUHP_AP_ONLINE_IDLE,
+ CPUHP_AP_SCHED_WAIT_EMPTY,
CPUHP_AP_SMPBOOT_THREADS,
CPUHP_AP_X86_VDSO_VMA_ONLINE,
CPUHP_AP_IRQ_AFFINITY_ONLINE,
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
index f74e45ae5..56e598d17 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -210,6 +210,11 @@ static inline int cpumask_any_and_distribute(const struct cpumask *src1p,
return cpumask_next_and(-1, src1p, src2p);
}
+static inline int cpumask_any_distribute(const struct cpumask *srcp)
+{
+ return cpumask_first(srcp);
+}
+
#define for_each_cpu(cpu, mask) \
for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
#define for_each_cpu_not(cpu, mask) \
@@ -263,6 +268,7 @@ int __pure cpumask_any_but(const struct cpumask *mask, unsigned int cpu);
unsigned int cpumask_local_spread(unsigned int i, int node);
int cpumask_any_and_distribute(const struct cpumask *src1p,
const struct cpumask *src2p);
+int cpumask_any_distribute(const struct cpumask *srcp);
/**
* for_each_cpu - iterate over every cpu in a mask
diff --git a/include/linux/dcache.h b/include/linux/dcache.h
index 4bb8b1759..c5821c04a 100644
--- a/include/linux/dcache.h
+++ b/include/linux/dcache.h
@@ -108,7 +108,7 @@ struct dentry {
union {
struct list_head d_lru; /* LRU list */
- wait_queue_head_t *d_wait; /* in-lookup ones only */
+ struct swait_queue_head *d_wait; /* in-lookup ones only */
};
struct list_head d_child; /* child of parent list */
struct list_head d_subdirs; /* our children */
@@ -251,7 +251,7 @@ extern void d_set_d_op(struct dentry *dentry, const struct dentry_operations *op
extern struct dentry * d_alloc(struct dentry *, const struct qstr *);
extern struct dentry * d_alloc_anon(struct super_block *);
extern struct dentry * d_alloc_parallel(struct dentry *, const struct qstr *,
- wait_queue_head_t *);
+ struct swait_queue_head *);
extern struct dentry * d_splice_alias(struct inode *, struct dentry *);
extern struct dentry * d_add_ci(struct dentry *, struct inode *, struct qstr *);
extern struct dentry * d_exact_alias(struct dentry *, struct inode *);
diff --git a/include/linux/debug_locks.h b/include/linux/debug_locks.h
index edb5c186b..3f49e6516 100644
--- a/include/linux/debug_locks.h
+++ b/include/linux/debug_locks.h
@@ -3,8 +3,7 @@
#define __LINUX_DEBUG_LOCKING_H
#include <linux/atomic.h>
-#include <linux/bug.h>
-#include <linux/printk.h>
+#include <linux/cache.h>
struct task_struct;
diff --git a/include/linux/delay.h b/include/linux/delay.h
index e8607992c..cd24f34b4 100644
--- a/include/linux/delay.h
+++ b/include/linux/delay.h
@@ -88,4 +88,10 @@ static inline void fsleep(unsigned long usecs)
msleep(DIV_ROUND_UP(usecs, 1000));
}
+#ifdef CONFIG_PREEMPT_RT
+extern void cpu_chill(void);
+#else
+# define cpu_chill() cpu_relax()
+#endif
+
#endif /* defined(_LINUX_DELAY_H) */
diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h
index de029656d..6f262f3d6 100644
--- a/include/linux/entry-common.h
+++ b/include/linux/entry-common.h
@@ -70,9 +70,10 @@
#define EXIT_TO_USER_MODE_WORK \
(_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
- _TIF_NEED_RESCHED | _TIF_PATCH_PENDING | _TIF_NOTIFY_SIGNAL | \
+ _TIF_NEED_RESCHED | _TIF_PATCH_PENDING | _TIF_NOTIFY_SIGNAL |_TIF_NEED_RESCHED_MASK | \
ARCH_EXIT_TO_USER_MODE_WORK)
+
/**
* arch_check_user_regs - Architecture specific sanity check for user mode regs
* @regs: Pointer to currents pt_regs
diff --git a/include/linux/eventfd.h b/include/linux/eventfd.h
index c1bd4883e..842d223df 100644
--- a/include/linux/eventfd.h
+++ b/include/linux/eventfd.h
@@ -14,6 +14,7 @@
#include <linux/err.h>
#include <linux/percpu-defs.h>
#include <linux/percpu.h>
+#include <linux/sched.h>
/*
* CAREFUL: Check include/uapi/asm-generic/fcntl.h when defining
@@ -44,11 +45,9 @@ int eventfd_ctx_remove_wait_queue(struct eventfd_ctx *ctx, wait_queue_entry_t *w
__u64 *cnt);
void eventfd_ctx_do_read(struct eventfd_ctx *ctx, __u64 *cnt);
-DECLARE_PER_CPU(int, eventfd_wake_count);
-
-static inline bool eventfd_signal_count(void)
+static inline bool eventfd_signal_allowed(void)
{
- return this_cpu_read(eventfd_wake_count);
+ return !current->in_eventfd_signal;
}
#else /* CONFIG_EVENTFD */
@@ -85,9 +84,9 @@ static inline int eventfd_ctx_remove_wait_queue(struct eventfd_ctx *ctx,
return -ENOSYS;
}
-static inline bool eventfd_signal_count(void)
+static inline bool eventfd_signal_allowed(void)
{
- return false;
+ return true;
}
static inline void eventfd_ctx_do_read(struct eventfd_ctx *ctx, __u64 *cnt)
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 7e8684e3f..07783fbe1 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -730,7 +730,7 @@ struct inode {
struct block_device *i_bdev;
struct cdev *i_cdev;
char *i_link;
- unsigned i_dir_seq;
+ unsigned __i_dir_seq;
};
__u32 i_generation;
diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h
index 754f67ac4..76878b357 100644
--- a/include/linux/hardirq.h
+++ b/include/linux/hardirq.h
@@ -6,6 +6,7 @@
#include <linux/preempt.h>
#include <linux/lockdep.h>
#include <linux/ftrace_irq.h>
+#include <linux/sched.h>
#include <linux/vtime.h>
#include <asm/hardirq.h>
@@ -32,9 +33,9 @@ static __always_inline void rcu_irq_enter_check_tick(void)
*/
#define __irq_enter() \
do { \
- account_irq_enter_time(current); \
preempt_count_add(HARDIRQ_OFFSET); \
lockdep_hardirq_enter(); \
+ account_hardirq_enter(current); \
} while (0)
/*
@@ -62,8 +63,8 @@ void irq_enter_rcu(void);
*/
#define __irq_exit() \
do { \
+ account_hardirq_exit(current); \
lockdep_hardirq_exit(); \
- account_irq_exit_time(current); \
preempt_count_sub(HARDIRQ_OFFSET); \
} while (0)
@@ -115,7 +116,6 @@ extern void rcu_nmi_exit(void);
do { \
lockdep_off(); \
arch_nmi_enter(); \
- printk_nmi_enter(); \
BUG_ON(in_nmi() == NMI_MASK); \
__preempt_count_add(NMI_OFFSET + HARDIRQ_OFFSET); \
} while (0)
@@ -134,7 +134,6 @@ extern void rcu_nmi_exit(void);
do { \
BUG_ON(!in_nmi()); \
__preempt_count_sub(NMI_OFFSET + HARDIRQ_OFFSET); \
- printk_nmi_exit(); \
arch_nmi_exit(); \
lockdep_on(); \
} while (0)
diff --git a/include/linux/highmem-internal.h b/include/linux/highmem-internal.h
new file mode 100644
index 000000000..f9bc6acd3
--- /dev/null
+++ b/include/linux/highmem-internal.h
@@ -0,0 +1,222 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_HIGHMEM_INTERNAL_H
+#define _LINUX_HIGHMEM_INTERNAL_H
+
+/*
+ * Outside of CONFIG_HIGHMEM to support X86 32bit iomap_atomic() cruft.
+ */
+#ifdef CONFIG_KMAP_LOCAL
+void *__kmap_local_pfn_prot(unsigned long pfn, pgprot_t prot);
+void *__kmap_local_page_prot(struct page *page, pgprot_t prot);
+void kunmap_local_indexed(void *vaddr);
+void kmap_local_fork(struct task_struct *tsk);
+void __kmap_local_sched_out(void);
+void __kmap_local_sched_in(void);
+static inline void kmap_assert_nomap(void)
+{
+ DEBUG_LOCKS_WARN_ON(current->kmap_ctrl.idx);
+}
+#else
+static inline void kmap_local_fork(struct task_struct *tsk) { }
+static inline void kmap_assert_nomap(void) { }
+#endif
+
+#ifdef CONFIG_HIGHMEM
+#include <asm/highmem.h>
+
+#ifndef ARCH_HAS_KMAP_FLUSH_TLB
+static inline void kmap_flush_tlb(unsigned long addr) { }
+#endif
+
+#ifndef kmap_prot
+#define kmap_prot PAGE_KERNEL
+#endif
+
+void *kmap_high(struct page *page);
+void kunmap_high(struct page *page);
+void __kmap_flush_unused(void);
+struct page *__kmap_to_page(void *addr);
+
+static inline void *kmap(struct page *page)
+{
+ void *addr;
+
+ might_sleep();
+ if (!PageHighMem(page))
+ addr = page_address(page);
+ else
+ addr = kmap_high(page);
+ kmap_flush_tlb((unsigned long)addr);
+ return addr;
+}
+
+static inline void kunmap(struct page *page)
+{
+ might_sleep();
+ if (!PageHighMem(page))
+ return;
+ kunmap_high(page);
+}
+
+static inline struct page *kmap_to_page(void *addr)
+{
+ return __kmap_to_page(addr);
+}
+
+static inline void kmap_flush_unused(void)
+{
+ __kmap_flush_unused();
+}
+
+static inline void *kmap_local_page(struct page *page)
+{
+ return __kmap_local_page_prot(page, kmap_prot);
+}
+
+static inline void *kmap_local_page_prot(struct page *page, pgprot_t prot)
+{
+ return __kmap_local_page_prot(page, prot);
+}
+
+static inline void *kmap_local_pfn(unsigned long pfn)
+{
+ return __kmap_local_pfn_prot(pfn, kmap_prot);
+}
+
+static inline void __kunmap_local(void *vaddr)
+{
+ kunmap_local_indexed(vaddr);
+}
+
+static inline void *kmap_atomic(struct page *page)
+{
+ if (IS_ENABLED(CONFIG_PREEMPT_RT))
+ migrate_disable();
+ else
+ preempt_disable();
+ pagefault_disable();
+ return __kmap_local_page_prot(page, kmap_prot);
+}
+
+static inline void __kunmap_atomic(void *addr)
+{
+ kunmap_local_indexed(addr);
+ pagefault_enable();
+ if (IS_ENABLED(CONFIG_PREEMPT_RT))
+ migrate_enable();
+ else
+ preempt_enable();
+}
+
+unsigned int __nr_free_highpages(void);
+extern atomic_long_t _totalhigh_pages;
+
+static inline unsigned int nr_free_highpages(void)
+{
+ return __nr_free_highpages();
+}
+
+static inline unsigned long totalhigh_pages(void)
+{
+ return (unsigned long)atomic_long_read(&_totalhigh_pages);
+}
+
+static inline void totalhigh_pages_inc(void)
+{
+ atomic_long_inc(&_totalhigh_pages);
+}
+
+static inline void totalhigh_pages_add(long count)
+{
+ atomic_long_add(count, &_totalhigh_pages);
+}
+
+#else /* CONFIG_HIGHMEM */
+
+static inline struct page *kmap_to_page(void *addr)
+{
+ return virt_to_page(addr);
+}
+
+static inline void *kmap(struct page *page)
+{
+ might_sleep();
+ return page_address(page);
+}
+
+static inline void kunmap_high(struct page *page) { }
+static inline void kmap_flush_unused(void) { }
+
+static inline void kunmap(struct page *page)
+{
+#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
+ kunmap_flush_on_unmap(page_address(page));
+#endif
+}
+
+static inline void *kmap_local_page(struct page *page)
+{
+ return page_address(page);
+}
+
+static inline void *kmap_local_page_prot(struct page *page, pgprot_t prot)
+{
+ return kmap_local_page(page);
+}
+
+static inline void *kmap_local_pfn(unsigned long pfn)
+{
+ return kmap_local_page(pfn_to_page(pfn));
+}
+
+static inline void __kunmap_local(void *addr)
+{
+#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
+ kunmap_flush_on_unmap(addr);
+#endif
+}
+
+static inline void *kmap_atomic(struct page *page)
+{
+ if (IS_ENABLED(CONFIG_PREEMPT_RT))
+ migrate_disable();
+ else
+ preempt_disable();
+ pagefault_disable();
+ return page_address(page);
+}
+
+static inline void __kunmap_atomic(void *addr)
+{
+#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
+ kunmap_flush_on_unmap(addr);
+#endif
+ pagefault_enable();
+ if (IS_ENABLED(CONFIG_PREEMPT_RT))
+ migrate_enable();
+ else
+ preempt_enable();
+}
+
+static inline unsigned int nr_free_highpages(void) { return 0; }
+static inline unsigned long totalhigh_pages(void) { return 0UL; }
+
+#endif /* CONFIG_HIGHMEM */
+
+/*
+ * Prevent people trying to call kunmap_atomic() as if it were kunmap()
+ * kunmap_atomic() should get the return value of kmap_atomic, not the page.
+ */
+#define kunmap_atomic(__addr) \
+do { \
+ BUILD_BUG_ON(__same_type((__addr), struct page *)); \
+ __kunmap_atomic(__addr); \
+} while (0)
+
+#define kunmap_local(__addr) \
+do { \
+ BUILD_BUG_ON(__same_type((__addr), struct page *)); \
+ __kunmap_local(__addr); \
+} while (0)
+
+#endif
diff --git a/include/linux/highmem.h b/include/linux/highmem.h
index 336781ec8..e60bf7e2a 100644
--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h
@@ -11,217 +11,137 @@
#include <asm/cacheflush.h>
-#ifndef ARCH_HAS_FLUSH_ANON_PAGE
-static inline void flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned long vmaddr)
-{
-}
-#endif
-
-#ifndef ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
-static inline void flush_kernel_dcache_page(struct page *page)
-{
-}
-static inline void flush_kernel_vmap_range(void *vaddr, int size)
-{
-}
-static inline void invalidate_kernel_vmap_range(void *vaddr, int size)
-{
-}
-#endif
-
-#include <asm/kmap_types.h>
-
-#ifdef CONFIG_HIGHMEM
-extern void *kmap_atomic_high_prot(struct page *page, pgprot_t prot);
-extern void kunmap_atomic_high(void *kvaddr);
-#include <asm/highmem.h>
-
-#ifndef ARCH_HAS_KMAP_FLUSH_TLB
-static inline void kmap_flush_tlb(unsigned long addr) { }
-#endif
-
-#ifndef kmap_prot
-#define kmap_prot PAGE_KERNEL
-#endif
-
-void *kmap_high(struct page *page);
-static inline void *kmap(struct page *page)
-{
- void *addr;
-
- might_sleep();
- if (!PageHighMem(page))
- addr = page_address(page);
- else
- addr = kmap_high(page);
- kmap_flush_tlb((unsigned long)addr);
- return addr;
-}
-
-void kunmap_high(struct page *page);
-
-static inline void kunmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return;
- kunmap_high(page);
-}
+#include "highmem-internal.h"
-/*
- * kmap_atomic/kunmap_atomic is significantly faster than kmap/kunmap because
- * no global lock is needed and because the kmap code must perform a global TLB
- * invalidation when the kmap pool wraps.
+/**
+ * kmap - Map a page for long term usage
+ * @page: Pointer to the page to be mapped
+ *
+ * Returns: The virtual address of the mapping
+ *
+ * Can only be invoked from preemptible task context because on 32bit
+ * systems with CONFIG_HIGHMEM enabled this function might sleep.
*
- * However when holding an atomic kmap it is not legal to sleep, so atomic
- * kmaps are appropriate for short, tight code paths only.
+ * For systems with CONFIG_HIGHMEM=n and for pages in the low memory area
+ * this returns the virtual address of the direct kernel mapping.
*
- * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
- * gives a more generic (and caching) interface. But kmap_atomic can
- * be used in IRQ contexts, so in some (very limited) cases we need
- * it.
+ * The returned virtual address is globally visible and valid up to the
+ * point where it is unmapped via kunmap(). The pointer can be handed to
+ * other contexts.
+ *
+ * For highmem pages on 32bit systems this can be slow as the mapping space
+ * is limited and protected by a global lock. In case that there is no
+ * mapping slot available the function blocks until a slot is released via
+ * kunmap().
*/
-static inline void *kmap_atomic_prot(struct page *page, pgprot_t prot)
-{
- preempt_disable();
- pagefault_disable();
- if (!PageHighMem(page))
- return page_address(page);
- return kmap_atomic_high_prot(page, prot);
-}
-#define kmap_atomic(page) kmap_atomic_prot(page, kmap_prot)
+static inline void *kmap(struct page *page);
-/* declarations for linux/mm/highmem.c */
-unsigned int nr_free_highpages(void);
-extern atomic_long_t _totalhigh_pages;
-static inline unsigned long totalhigh_pages(void)
-{
- return (unsigned long)atomic_long_read(&_totalhigh_pages);
-}
-
-static inline void totalhigh_pages_inc(void)
-{
- atomic_long_inc(&_totalhigh_pages);
-}
-
-static inline void totalhigh_pages_dec(void)
-{
- atomic_long_dec(&_totalhigh_pages);
-}
-
-static inline void totalhigh_pages_add(long count)
-{
- atomic_long_add(count, &_totalhigh_pages);
-}
-
-static inline void totalhigh_pages_set(long val)
-{
- atomic_long_set(&_totalhigh_pages, val);
-}
-
-void kmap_flush_unused(void);
-
-struct page *kmap_to_page(void *addr);
-
-#else /* CONFIG_HIGHMEM */
+/**
+ * kunmap - Unmap the virtual address mapped by kmap()
+ * @addr: Virtual address to be unmapped
+ *
+ * Counterpart to kmap(). A NOOP for CONFIG_HIGHMEM=n and for mappings of
+ * pages in the low memory area.
+ */
+static inline void kunmap(struct page *page);
-static inline unsigned int nr_free_highpages(void) { return 0; }
+/**
+ * kmap_to_page - Get the page for a kmap'ed address
+ * @addr: The address to look up
+ *
+ * Returns: The page which is mapped to @addr.
+ */
+static inline struct page *kmap_to_page(void *addr);
-static inline struct page *kmap_to_page(void *addr)
-{
- return virt_to_page(addr);
-}
+/**
+ * kmap_flush_unused - Flush all unused kmap mappings in order to
+ * remove stray mappings
+ */
+static inline void kmap_flush_unused(void);
-static inline unsigned long totalhigh_pages(void) { return 0UL; }
+/**
+ * kmap_local_page - Map a page for temporary usage
+ * @page: Pointer to the page to be mapped
+ *
+ * Returns: The virtual address of the mapping
+ *
+ * Can be invoked from any context.
+ *
+ * Requires careful handling when nesting multiple mappings because the map
+ * management is stack based. The unmap has to be in the reverse order of
+ * the map operation:
+ *
+ * addr1 = kmap_local_page(page1);
+ * addr2 = kmap_local_page(page2);
+ * ...
+ * kunmap_local(addr2);
+ * kunmap_local(addr1);
+ *
+ * Unmapping addr1 before addr2 is invalid and causes malfunction.
+ *
+ * Contrary to kmap() mappings the mapping is only valid in the context of
+ * the caller and cannot be handed to other contexts.
+ *
+ * On CONFIG_HIGHMEM=n kernels and for low memory pages this returns the
+ * virtual address of the direct mapping. Only real highmem pages are
+ * temporarily mapped.
+ *
+ * While it is significantly faster than kmap() for the higmem case it
+ * comes with restrictions about the pointer validity. Only use when really
+ * necessary.
+ *
+ * On HIGHMEM enabled systems mapping a highmem page has the side effect of
+ * disabling migration in order to keep the virtual address stable across
+ * preemption. No caller of kmap_local_page() can rely on this side effect.
+ */
+static inline void *kmap_local_page(struct page *page);
-static inline void *kmap(struct page *page)
-{
- might_sleep();
- return page_address(page);
-}
+/**
+ * kmap_atomic - Atomically map a page for temporary usage - Deprecated!
+ * @page: Pointer to the page to be mapped
+ *
+ * Returns: The virtual address of the mapping
+ *
+ * Effectively a wrapper around kmap_local_page() which disables pagefaults
+ * and preemption.
+ *
+ * Do not use in new code. Use kmap_local_page() instead.
+ */
+static inline void *kmap_atomic(struct page *page);
-static inline void kunmap_high(struct page *page)
-{
-}
+/**
+ * kunmap_atomic - Unmap the virtual address mapped by kmap_atomic()
+ * @addr: Virtual address to be unmapped
+ *
+ * Counterpart to kmap_atomic().
+ *
+ * Effectively a wrapper around kunmap_local() which additionally undoes
+ * the side effects of kmap_atomic(), i.e. reenabling pagefaults and
+ * preemption.
+ */
-static inline void kunmap(struct page *page)
-{
-#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
- kunmap_flush_on_unmap(page_address(page));
-#endif
-}
+/* Highmem related interfaces for management code */
+static inline unsigned int nr_free_highpages(void);
+static inline unsigned long totalhigh_pages(void);
-static inline void *kmap_atomic(struct page *page)
+#ifndef ARCH_HAS_FLUSH_ANON_PAGE
+static inline void flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned long vmaddr)
{
- preempt_disable();
- pagefault_disable();
- return page_address(page);
}
-#define kmap_atomic_prot(page, prot) kmap_atomic(page)
-
-static inline void kunmap_atomic_high(void *addr)
-{
- /*
- * Mostly nothing to do in the CONFIG_HIGHMEM=n case as kunmap_atomic()
- * handles re-enabling faults + preemption
- */
-#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
- kunmap_flush_on_unmap(addr);
#endif
-}
-#define kmap_atomic_pfn(pfn) kmap_atomic(pfn_to_page(pfn))
-
-#define kmap_flush_unused() do {} while(0)
-
-#endif /* CONFIG_HIGHMEM */
-
-#if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
-
-DECLARE_PER_CPU(int, __kmap_atomic_idx);
-
-static inline int kmap_atomic_idx_push(void)
+#ifndef ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
+static inline void flush_kernel_dcache_page(struct page *page)
{
- int idx = __this_cpu_inc_return(__kmap_atomic_idx) - 1;
-
-#ifdef CONFIG_DEBUG_HIGHMEM
- WARN_ON_ONCE(in_irq() && !irqs_disabled());
- BUG_ON(idx >= KM_TYPE_NR);
-#endif
- return idx;
}
-
-static inline int kmap_atomic_idx(void)
+static inline void flush_kernel_vmap_range(void *vaddr, int size)
{
- return __this_cpu_read(__kmap_atomic_idx) - 1;
}
-
-static inline void kmap_atomic_idx_pop(void)
+static inline void invalidate_kernel_vmap_range(void *vaddr, int size)
{
-#ifdef CONFIG_DEBUG_HIGHMEM
- int idx = __this_cpu_dec_return(__kmap_atomic_idx);
-
- BUG_ON(idx < 0);
-#else
- __this_cpu_dec(__kmap_atomic_idx);
-#endif
}
-
#endif
-/*
- * Prevent people trying to call kunmap_atomic() as if it were kunmap()
- * kunmap_atomic() should get the return value of kmap_atomic, not the page.
- */
-#define kunmap_atomic(addr) \
-do { \
- BUILD_BUG_ON(__same_type((addr), struct page *)); \
- kunmap_atomic_high(addr); \
- pagefault_enable(); \
- preempt_enable(); \
-} while (0)
-
-
/* when CONFIG_HIGHMEM is not set these will be plain clear/copy_page */
#ifndef clear_user_highpage
static inline void clear_user_highpage(struct page *page, unsigned long vaddr)
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 22240a8c3..fc162c252 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -542,7 +542,7 @@ struct softirq_action
asmlinkage void do_softirq(void);
asmlinkage void __do_softirq(void);
-#ifdef __ARCH_HAS_DO_SOFTIRQ
+#if defined(__ARCH_HAS_DO_SOFTIRQ) && !defined(CONFIG_PREEMPT_RT)
void do_softirq_own_stack(void);
#else
static inline void do_softirq_own_stack(void)
@@ -637,26 +637,21 @@ enum
TASKLET_STATE_RUN /* Tasklet is running (SMP only) */
};
-#ifdef CONFIG_SMP
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT)
static inline int tasklet_trylock(struct tasklet_struct *t)
{
return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
}
-static inline void tasklet_unlock(struct tasklet_struct *t)
-{
- smp_mb__before_atomic();
- clear_bit(TASKLET_STATE_RUN, &(t)->state);
-}
+void tasklet_unlock(struct tasklet_struct *t);
+void tasklet_unlock_wait(struct tasklet_struct *t);
+void tasklet_unlock_spin_wait(struct tasklet_struct *t);
-static inline void tasklet_unlock_wait(struct tasklet_struct *t)
-{
- while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
-}
#else
-#define tasklet_trylock(t) 1
-#define tasklet_unlock_wait(t) do { } while (0)
-#define tasklet_unlock(t) do { } while (0)
+static inline int tasklet_trylock(struct tasklet_struct *t) { return 1; }
+static inline void tasklet_unlock(struct tasklet_struct *t) { }
+static inline void tasklet_unlock_wait(struct tasklet_struct *t) { }
+static inline void tasklet_unlock_spin_wait(struct tasklet_struct *t) { }
#endif
extern void __tasklet_schedule(struct tasklet_struct *t);
@@ -681,6 +676,17 @@ static inline void tasklet_disable_nosync(struct tasklet_struct *t)
smp_mb__after_atomic();
}
+/*
+ * Do not use in new code. Disabling tasklets from atomic contexts is
+ * error prone and should be avoided.
+ */
+static inline void tasklet_disable_in_atomic(struct tasklet_struct *t)
+{
+ tasklet_disable_nosync(t);
+ tasklet_unlock_spin_wait(t);
+ smp_mb();
+}
+
static inline void tasklet_disable(struct tasklet_struct *t)
{
tasklet_disable_nosync(t);
diff --git a/include/linux/io-mapping.h b/include/linux/io-mapping.h
index c75e4d3d8..4bb8223f2 100644
--- a/include/linux/io-mapping.h
+++ b/include/linux/io-mapping.h
@@ -60,22 +60,20 @@ io_mapping_fini(struct io_mapping *mapping)
iomap_free(mapping->base, mapping->size);
}
-/* Atomic map/unmap */
+/* Temporary mappings which are only valid in the current context */
static inline void __iomem *
-io_mapping_map_atomic_wc(struct io_mapping *mapping,
- unsigned long offset)
+io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset)
{
resource_size_t phys_addr;
BUG_ON(offset >= mapping->size);
phys_addr = mapping->base + offset;
- return iomap_atomic_prot_pfn(PHYS_PFN(phys_addr), mapping->prot);
+ return __iomap_local_pfn_prot(PHYS_PFN(phys_addr), mapping->prot);
}
-static inline void
-io_mapping_unmap_atomic(void __iomem *vaddr)
+static inline void io_mapping_unmap_local(void __iomem *vaddr)
{
- iounmap_atomic(vaddr);
+ kunmap_local_indexed((void __force *)vaddr);
}
static inline void __iomem *
@@ -97,7 +95,7 @@ io_mapping_unmap(void __iomem *vaddr)
iounmap(vaddr);
}
-#else
+#else /* HAVE_ATOMIC_IOMAP */
#include <linux/uaccess.h>
@@ -144,25 +142,19 @@ io_mapping_unmap(void __iomem *vaddr)
{
}
-/* Atomic map/unmap */
+/* Temporary mappings which are only valid in the current context */
static inline void __iomem *
-io_mapping_map_atomic_wc(struct io_mapping *mapping,
- unsigned long offset)
+io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset)
{
- preempt_disable();
- pagefault_disable();
return io_mapping_map_wc(mapping, offset, PAGE_SIZE);
}
-static inline void
-io_mapping_unmap_atomic(void __iomem *vaddr)
+static inline void io_mapping_unmap_local(void __iomem *vaddr)
{
io_mapping_unmap(vaddr);
- pagefault_enable();
- preempt_enable();
}
-#endif /* HAVE_ATOMIC_IOMAP */
+#endif /* !HAVE_ATOMIC_IOMAP */
static inline struct io_mapping *
io_mapping_create_wc(resource_size_t base,
diff --git a/include/linux/irq_cpustat.h b/include/linux/irq_cpustat.h
deleted file mode 100644
index 6e8895cd4..000000000
--- a/include/linux/irq_cpustat.h
+++ /dev/null
@@ -1,28 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __irq_cpustat_h
-#define __irq_cpustat_h
-
-/*
- * Contains default mappings for irq_cpustat_t, used by almost every
- * architecture. Some arch (like s390) have per cpu hardware pages and
- * they define their own mappings for irq_stat.
- *
- * Keith Owens <kaos@ocs.com.au> July 2000.
- */
-
-
-/*
- * Simple wrappers reducing source bloat. Define all irq_stat fields
- * here, even ones that are arch dependent. That way we get common
- * definitions instead of differing sets for each arch.
- */
-
-#ifndef __ARCH_IRQ_STAT
-DECLARE_PER_CPU_ALIGNED(irq_cpustat_t, irq_stat); /* defined in asm/hardirq.h */
-#define __IRQ_STAT(cpu, member) (per_cpu(irq_stat.member, cpu))
-#endif
-
-/* arch dependent irq_stat fields */
-#define nmi_count(cpu) __IRQ_STAT((cpu), __nmi_count) /* i386 */
-
-#endif /* __irq_cpustat_h */
diff --git a/include/linux/irq_work.h b/include/linux/irq_work.h
index ec2a47a81..9448e2bfc 100644
--- a/include/linux/irq_work.h
+++ b/include/linux/irq_work.h
@@ -3,6 +3,7 @@
#define _LINUX_IRQ_WORK_H
#include <linux/smp_types.h>
+#include <linux/rcuwait.h>
/*
* An entry can be in one of four states:
@@ -16,11 +17,13 @@
struct irq_work {
struct __call_single_node node;
void (*func)(struct irq_work *);
+ struct rcuwait irqwait;
};
#define __IRQ_WORK_INIT(_func, _flags) (struct irq_work){ \
.node = { .u_flags = (_flags), }, \
.func = (_func), \
+ .irqwait = __RCUWAIT_INITIALIZER(irqwait), \
}
#define IRQ_WORK_INIT(_func) __IRQ_WORK_INIT(_func, 0)
@@ -46,6 +49,11 @@ static inline bool irq_work_is_busy(struct irq_work *work)
return atomic_read(&work->node.a_flags) & IRQ_WORK_BUSY;
}
+static inline bool irq_work_is_hard(struct irq_work *work)
+{
+ return atomic_read(&work->node.a_flags) & IRQ_WORK_HARD_IRQ;
+}
+
bool irq_work_queue(struct irq_work *work);
bool irq_work_queue_on(struct irq_work *work, int cpu);
diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h
index 8710502b3..db4c4d3f8 100644
--- a/include/linux/irqdesc.h
+++ b/include/linux/irqdesc.h
@@ -68,6 +68,7 @@ struct irq_desc {
unsigned int irqs_unhandled;
atomic_t threads_handled;
int threads_handled_last;
+ u64 random_ip;
raw_spinlock_t lock;
struct cpumask *percpu_enabled;
const struct cpumask *percpu_affinity;
diff --git a/include/linux/irqflags.h b/include/linux/irqflags.h
index eea9adf9d..5fee7ff9c 100644
--- a/include/linux/irqflags.h
+++ b/include/linux/irqflags.h
@@ -71,14 +71,6 @@ do { \
do { \
__this_cpu_dec(hardirq_context); \
} while (0)
-# define lockdep_softirq_enter() \
-do { \
- current->softirq_context++; \
-} while (0)
-# define lockdep_softirq_exit() \
-do { \
- current->softirq_context--; \
-} while (0)
# define lockdep_hrtimer_enter(__hrtimer) \
({ \
@@ -140,6 +132,21 @@ do { \
# define lockdep_irq_work_exit(__work) do { } while (0)
#endif
+#if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PREEMPT_RT)
+# define lockdep_softirq_enter() \
+do { \
+ current->softirq_context++; \
+} while (0)
+# define lockdep_softirq_exit() \
+do { \
+ current->softirq_context--; \
+} while (0)
+
+#else
+# define lockdep_softirq_enter() do { } while (0)
+# define lockdep_softirq_exit() do { } while (0)
+#endif
+
#if defined(CONFIG_IRQSOFF_TRACER) || \
defined(CONFIG_PREEMPT_TRACER)
extern void stop_critical_timings(void);
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 2023afa63..42ce73380 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -223,6 +223,7 @@ static __always_inline void might_resched(void)
extern void ___might_sleep(const char *file, int line, int preempt_offset);
extern void __might_sleep(const char *file, int line, int preempt_offset);
extern void __cant_sleep(const char *file, int line, int preempt_offset);
+extern void __cant_migrate(const char *file, int line);
/**
* might_sleep - annotation for functions that can sleep
@@ -238,6 +239,10 @@ extern void __cant_sleep(const char *file, int line, int preempt_offset);
*/
# define might_sleep() \
do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
+
+# define might_sleep_no_state_check() \
+ do { ___might_sleep(__FILE__, __LINE__, 0); } while (0)
+
/**
* cant_sleep - annotation for functions that cannot sleep
*
@@ -246,6 +251,18 @@ extern void __cant_sleep(const char *file, int line, int preempt_offset);
# define cant_sleep() \
do { __cant_sleep(__FILE__, __LINE__, 0); } while (0)
# define sched_annotate_sleep() (current->task_state_change = 0)
+
+/**
+ * cant_migrate - annotation for functions that cannot migrate
+ *
+ * Will print a stack trace if executed in code which is migratable
+ */
+# define cant_migrate() \
+ do { \
+ if (IS_ENABLED(CONFIG_SMP)) \
+ __cant_migrate(__FILE__, __LINE__); \
+ } while (0)
+
/**
* non_block_start - annotate the start of section where sleeping is prohibited
*
@@ -269,7 +286,9 @@ extern void __cant_sleep(const char *file, int line, int preempt_offset);
static inline void __might_sleep(const char *file, int line,
int preempt_offset) { }
# define might_sleep() do { might_resched(); } while (0)
+# define might_sleep_no_state_check() do { might_resched(); } while (0)
# define cant_sleep() do { } while (0)
+# define cant_migrate() do { } while (0)
# define sched_annotate_sleep() do { } while (0)
# define non_block_start() do { } while (0)
# define non_block_end() do { } while (0)
@@ -277,13 +296,6 @@ extern void __cant_sleep(const char *file, int line, int preempt_offset);
#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
-#ifndef CONFIG_PREEMPT_RT
-# define cant_migrate() cant_sleep()
-#else
- /* Placeholder for now */
-# define cant_migrate() do { } while (0)
-#endif
-
/**
* abs - return absolute value of an argument
* @x: the value. If it is unsigned type, it is converted to signed type first.
diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h
index 3378bcbe5..86673930c 100644
--- a/include/linux/kmsg_dump.h
+++ b/include/linux/kmsg_dump.h
@@ -29,6 +29,18 @@ enum kmsg_dump_reason {
KMSG_DUMP_MAX
};
+/**
+ * struct kmsg_dumper_iter - iterator for kernel crash message dumper
+ * @active: Flag that specifies if this is currently dumping
+ * @cur_seq: Points to the oldest message to dump (private)
+ * @next_seq: Points after the newest message to dump (private)
+ */
+struct kmsg_dumper_iter {
+ bool active;
+ u64 cur_seq;
+ u64 next_seq;
+};
+
/**
* struct kmsg_dumper - kernel crash message dumper structure
* @list: Entry in the dumper list (private)
@@ -39,33 +51,22 @@ enum kmsg_dump_reason {
*/
struct kmsg_dumper {
struct list_head list;
- void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason);
+ void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason,
+ struct kmsg_dumper_iter *iter);
enum kmsg_dump_reason max_reason;
- bool active;
bool registered;
-
- /* private state of the kmsg iterator */
- u32 cur_idx;
- u32 next_idx;
- u64 cur_seq;
- u64 next_seq;
};
#ifdef CONFIG_PRINTK
void kmsg_dump(enum kmsg_dump_reason reason);
-bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog,
- char *line, size_t size, size_t *len);
-
-bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
+bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog,
char *line, size_t size, size_t *len);
-bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
- char *buf, size_t size, size_t *len);
-
-void kmsg_dump_rewind_nolock(struct kmsg_dumper *dumper);
+bool kmsg_dump_get_buffer(struct kmsg_dumper_iter *iter, bool syslog,
+ char *buf, size_t size, size_t *len_out);
-void kmsg_dump_rewind(struct kmsg_dumper *dumper);
+void kmsg_dump_rewind(struct kmsg_dumper_iter *iter);
int kmsg_dump_register(struct kmsg_dumper *dumper);
@@ -77,30 +78,19 @@ static inline void kmsg_dump(enum kmsg_dump_reason reason)
{
}
-static inline bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper,
- bool syslog, const char *line,
- size_t size, size_t *len)
-{
- return false;
-}
-
-static inline bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
+static inline bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog,
const char *line, size_t size, size_t *len)
{
return false;
}
-static inline bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
+static inline bool kmsg_dump_get_buffer(struct kmsg_dumper_iter *iter, bool syslog,
char *buf, size_t size, size_t *len)
{
return false;
}
-static inline void kmsg_dump_rewind_nolock(struct kmsg_dumper *dumper)
-{
-}
-
-static inline void kmsg_dump_rewind(struct kmsg_dumper *dumper)
+static inline void kmsg_dump_rewind(struct kmsg_dumper_iter *iter)
{
}
diff --git a/include/linux/local_lock_internal.h b/include/linux/local_lock_internal.h
index 3f02b8186..1b8ae0349 100644
--- a/include/linux/local_lock_internal.h
+++ b/include/linux/local_lock_internal.h
@@ -7,13 +7,39 @@
#include <linux/lockdep.h>
typedef struct {
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
+#ifdef CONFIG_PREEMPT_RT
+ spinlock_t lock;
+ struct task_struct *owner;
+ int nestcnt;
+
+#elif defined(CONFIG_DEBUG_LOCK_ALLOC)
struct lockdep_map dep_map;
struct task_struct *owner;
#endif
} local_lock_t;
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
+#ifdef CONFIG_PREEMPT_RT
+
+#define INIT_LOCAL_LOCK(lockname) { \
+ __SPIN_LOCK_UNLOCKED((lockname).lock), \
+ .owner = NULL, \
+ .nestcnt = 0, \
+ }
+
+static inline void ___local_lock_init(local_lock_t *l)
+{
+ l->owner = NULL;
+ l->nestcnt = 0;
+}
+
+#define __local_lock_init(l) \
+do { \
+ spin_lock_init(&(l)->lock); \
+ ___local_lock_init(l); \
+} while (0)
+
+#elif defined(CONFIG_DEBUG_LOCK_ALLOC)
+
# define LOCAL_LOCK_DEBUG_INIT(lockname) \
.dep_map = { \
.name = #lockname, \
@@ -21,7 +47,33 @@ typedef struct {
.lock_type = LD_LOCK_PERCPU, \
}, \
.owner = NULL,
+#endif
+
+#ifdef CONFIG_PREEMPT_RT
+static inline void local_lock_acquire(local_lock_t *l)
+{
+ if (l->owner != current) {
+ spin_lock(&l->lock);
+ DEBUG_LOCKS_WARN_ON(l->owner);
+ DEBUG_LOCKS_WARN_ON(l->nestcnt);
+ l->owner = current;
+ }
+ l->nestcnt++;
+}
+
+static inline void local_lock_release(local_lock_t *l)
+{
+ DEBUG_LOCKS_WARN_ON(l->nestcnt == 0);
+ DEBUG_LOCKS_WARN_ON(l->owner != current);
+ if (--l->nestcnt)
+ return;
+
+ l->owner = NULL;
+ spin_unlock(&l->lock);
+}
+
+#elif defined(CONFIG_DEBUG_LOCK_ALLOC)
static inline void local_lock_acquire(local_lock_t *l)
{
lock_map_acquire(&l->dep_map);
@@ -47,6 +99,47 @@ static inline void local_lock_release(local_lock_t *l) { }
static inline void local_lock_debug_init(local_lock_t *l) { }
#endif /* !CONFIG_DEBUG_LOCK_ALLOC */
+#ifdef CONFIG_PREEMPT_RT
+
+#define __local_lock(lock) \
+ do { \
+ migrate_disable(); \
+ local_lock_acquire(this_cpu_ptr(lock)); \
+ } while (0)
+
+#define __local_unlock(lock) \
+ do { \
+ local_lock_release(this_cpu_ptr(lock)); \
+ migrate_enable(); \
+ } while (0)
+
+#define __local_lock_irq(lock) \
+ do { \
+ migrate_disable(); \
+ local_lock_acquire(this_cpu_ptr(lock)); \
+ } while (0)
+
+#define __local_lock_irqsave(lock, flags) \
+ do { \
+ migrate_disable(); \
+ flags = 0; \
+ local_lock_acquire(this_cpu_ptr(lock)); \
+ } while (0)
+
+#define __local_unlock_irq(lock) \
+ do { \
+ local_lock_release(this_cpu_ptr(lock)); \
+ migrate_enable(); \
+ } while (0)
+
+#define __local_unlock_irqrestore(lock, flags) \
+ do { \
+ local_lock_release(this_cpu_ptr(lock)); \
+ migrate_enable(); \
+ } while (0)
+
+#else
+
#define INIT_LOCAL_LOCK(lockname) { LOCAL_LOCK_DEBUG_INIT(lockname) }
#define __local_lock_init(lock) \
@@ -66,6 +159,12 @@ do { \
local_lock_acquire(this_cpu_ptr(lock)); \
} while (0)
+#define __local_unlock(lock) \
+ do { \
+ local_lock_release(this_cpu_ptr(lock)); \
+ preempt_enable(); \
+ } while (0)
+
#define __local_lock_irq(lock) \
do { \
local_irq_disable(); \
@@ -78,12 +177,6 @@ do { \
local_lock_acquire(this_cpu_ptr(lock)); \
} while (0)
-#define __local_unlock(lock) \
- do { \
- local_lock_release(this_cpu_ptr(lock)); \
- preempt_enable(); \
- } while (0)
-
#define __local_unlock_irq(lock) \
do { \
local_lock_release(this_cpu_ptr(lock)); \
@@ -95,3 +188,5 @@ do { \
local_lock_release(this_cpu_ptr(lock)); \
local_irq_restore(flags); \
} while (0)
+
+#endif
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index d1c5946ad..f8099b6c1 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -13,6 +13,7 @@
#include <linux/completion.h>
#include <linux/cpumask.h>
#include <linux/uprobes.h>
+#include <linux/rcupdate.h>
#include <linux/page-flags-layout.h>
#include <linux/workqueue.h>
#include <linux/seqlock.h>
@@ -603,6 +604,9 @@ struct mm_struct {
bool tlb_flush_batched;
#endif
struct uprobes_state uprobes_state;
+#ifdef CONFIG_PREEMPT_RT
+ struct rcu_head delayed_drop;
+#endif
#ifdef CONFIG_HUGETLB_PAGE
atomic_long_t hugetlb_usage;
#endif
diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index a8f1516ee..6faec5aa0 100644
--- a/include/linux/mutex.h
+++ b/include/linux/mutex.h
@@ -24,6 +24,20 @@ struct device;
struct ww_acquire_ctx;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \
+ , .dep_map = { \
+ .name = #lockname, \
+ .wait_type_inner = LD_WAIT_SLEEP, \
+ }
+#else
+# define __DEP_MAP_MUTEX_INITIALIZER(lockname)
+#endif
+
+#ifdef CONFIG_PREEMPT_RT
+# include <linux/mutex_rt.h>
+#else
+
/*
* Simple, straightforward mutexes with strict semantics:
*
@@ -70,14 +84,6 @@ struct mutex {
struct ww_class;
struct ww_acquire_ctx;
-struct ww_mutex {
- struct mutex base;
- struct ww_acquire_ctx *ctx;
-#ifdef CONFIG_DEBUG_MUTEXES
- struct ww_class *ww_class;
-#endif
-};
-
/*
* This is the control structure for tasks blocked on mutex,
* which resides on the blocked task's kernel stack:
@@ -121,16 +127,6 @@ do { \
__mutex_init((mutex), #mutex, &__key); \
} while (0)
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \
- , .dep_map = { \
- .name = #lockname, \
- .wait_type_inner = LD_WAIT_SLEEP, \
- }
-#else
-# define __DEP_MAP_MUTEX_INITIALIZER(lockname)
-#endif
-
#define __MUTEX_INITIALIZER(lockname) \
{ .owner = ATOMIC_LONG_INIT(0) \
, .wait_lock = __SPIN_LOCK_UNLOCKED(lockname.wait_lock) \
@@ -251,4 +247,6 @@ enum mutex_trylock_recursive_enum {
extern /* __deprecated */ __must_check enum mutex_trylock_recursive_enum
mutex_trylock_recursive(struct mutex *lock);
+#endif /* !PREEMPT_RT */
+
#endif /* __LINUX_MUTEX_H */
diff --git a/include/linux/mutex_rt.h b/include/linux/mutex_rt.h
new file mode 100644
index 000000000..f0b2e07cd
--- /dev/null
+++ b/include/linux/mutex_rt.h
@@ -0,0 +1,130 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef __LINUX_MUTEX_RT_H
+#define __LINUX_MUTEX_RT_H
+
+#ifndef __LINUX_MUTEX_H
+#error "Please include mutex.h"
+#endif
+
+#include <linux/rtmutex.h>
+
+/* FIXME: Just for __lockfunc */
+#include <linux/spinlock.h>
+
+struct mutex {
+ struct rt_mutex lock;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif
+};
+
+#define __MUTEX_INITIALIZER(mutexname) \
+ { \
+ .lock = __RT_MUTEX_INITIALIZER(mutexname.lock) \
+ __DEP_MAP_MUTEX_INITIALIZER(mutexname) \
+ }
+
+#define DEFINE_MUTEX(mutexname) \
+ struct mutex mutexname = __MUTEX_INITIALIZER(mutexname)
+
+extern void __mutex_do_init(struct mutex *lock, const char *name, struct lock_class_key *key);
+extern void __lockfunc _mutex_lock(struct mutex *lock);
+extern void __lockfunc _mutex_lock_io_nested(struct mutex *lock, int subclass);
+extern int __lockfunc _mutex_lock_interruptible(struct mutex *lock);
+extern int __lockfunc _mutex_lock_killable(struct mutex *lock);
+extern void __lockfunc _mutex_lock_nested(struct mutex *lock, int subclass);
+extern void __lockfunc _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest_lock);
+extern int __lockfunc _mutex_lock_interruptible_nested(struct mutex *lock, int subclass);
+extern int __lockfunc _mutex_lock_killable_nested(struct mutex *lock, int subclass);
+extern int __lockfunc _mutex_trylock(struct mutex *lock);
+extern void __lockfunc _mutex_unlock(struct mutex *lock);
+
+#define mutex_is_locked(l) rt_mutex_is_locked(&(l)->lock)
+#define mutex_lock(l) _mutex_lock(l)
+#define mutex_lock_interruptible(l) _mutex_lock_interruptible(l)
+#define mutex_lock_killable(l) _mutex_lock_killable(l)
+#define mutex_trylock(l) _mutex_trylock(l)
+#define mutex_unlock(l) _mutex_unlock(l)
+#define mutex_lock_io(l) _mutex_lock_io_nested(l, 0);
+
+#define __mutex_owner(l) ((l)->lock.owner)
+
+#ifdef CONFIG_DEBUG_MUTEXES
+#define mutex_destroy(l) rt_mutex_destroy(&(l)->lock)
+#else
+static inline void mutex_destroy(struct mutex *lock) {}
+#endif
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define mutex_lock_nested(l, s) _mutex_lock_nested(l, s)
+# define mutex_lock_interruptible_nested(l, s) \
+ _mutex_lock_interruptible_nested(l, s)
+# define mutex_lock_killable_nested(l, s) \
+ _mutex_lock_killable_nested(l, s)
+# define mutex_lock_io_nested(l, s) _mutex_lock_io_nested(l, s)
+
+# define mutex_lock_nest_lock(lock, nest_lock) \
+do { \
+ typecheck(struct lockdep_map *, &(nest_lock)->dep_map); \
+ _mutex_lock_nest_lock(lock, &(nest_lock)->dep_map); \
+} while (0)
+
+#else
+# define mutex_lock_nested(l, s) _mutex_lock(l)
+# define mutex_lock_interruptible_nested(l, s) \
+ _mutex_lock_interruptible(l)
+# define mutex_lock_killable_nested(l, s) \
+ _mutex_lock_killable(l)
+# define mutex_lock_nest_lock(lock, nest_lock) mutex_lock(lock)
+# define mutex_lock_io_nested(l, s) _mutex_lock_io_nested(l, s)
+#endif
+
+# define mutex_init(mutex) \
+do { \
+ static struct lock_class_key __key; \
+ \
+ rt_mutex_init(&(mutex)->lock); \
+ __mutex_do_init((mutex), #mutex, &__key); \
+} while (0)
+
+# define __mutex_init(mutex, name, key) \
+do { \
+ rt_mutex_init(&(mutex)->lock); \
+ __mutex_do_init((mutex), name, key); \
+} while (0)
+
+/**
+ * These values are chosen such that FAIL and SUCCESS match the
+ * values of the regular mutex_trylock().
+ */
+enum mutex_trylock_recursive_enum {
+ MUTEX_TRYLOCK_FAILED = 0,
+ MUTEX_TRYLOCK_SUCCESS = 1,
+ MUTEX_TRYLOCK_RECURSIVE,
+};
+/**
+ * mutex_trylock_recursive - trylock variant that allows recursive locking
+ * @lock: mutex to be locked
+ *
+ * This function should not be used, _ever_. It is purely for hysterical GEM
+ * raisins, and once those are gone this will be removed.
+ *
+ * Returns:
+ * MUTEX_TRYLOCK_FAILED - trylock failed,
+ * MUTEX_TRYLOCK_SUCCESS - lock acquired,
+ * MUTEX_TRYLOCK_RECURSIVE - we already owned the lock.
+ */
+int __rt_mutex_owner_current(struct rt_mutex *lock);
+
+static inline /* __deprecated */ __must_check enum mutex_trylock_recursive_enum
+mutex_trylock_recursive(struct mutex *lock)
+{
+ if (unlikely(__rt_mutex_owner_current(&lock->lock)))
+ return MUTEX_TRYLOCK_RECURSIVE;
+
+ return mutex_trylock(lock);
+}
+
+extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock);
+
+#endif
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 33442fd01..4612bb5be 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1675,7 +1675,7 @@ struct nfs_unlinkdata {
struct nfs_removeargs args;
struct nfs_removeres res;
struct dentry *dentry;
- wait_queue_head_t wq;
+ struct swait_queue_head wq;
const struct cred *cred;
struct nfs_fattr dir_attr;
long timeout;
diff --git a/include/linux/notifier.h b/include/linux/notifier.h
index 2fb373a5c..723bc2df6 100644
--- a/include/linux/notifier.h
+++ b/include/linux/notifier.h
@@ -58,7 +58,7 @@ struct notifier_block {
};
struct atomic_notifier_head {
- spinlock_t lock;
+ raw_spinlock_t lock;
struct notifier_block __rcu *head;
};
@@ -78,7 +78,7 @@ struct srcu_notifier_head {
};
#define ATOMIC_INIT_NOTIFIER_HEAD(name) do { \
- spin_lock_init(&(name)->lock); \
+ raw_spin_lock_init(&(name)->lock); \
(name)->head = NULL; \
} while (0)
#define BLOCKING_INIT_NOTIFIER_HEAD(name) do { \
@@ -95,7 +95,7 @@ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh);
cleanup_srcu_struct(&(name)->srcu);
#define ATOMIC_NOTIFIER_INIT(name) { \
- .lock = __SPIN_LOCK_UNLOCKED(name.lock), \
+ .lock = __RAW_SPIN_LOCK_UNLOCKED(name.lock), \
.head = NULL }
#define BLOCKING_NOTIFIER_INIT(name) { \
.rwsem = __RWSEM_INITIALIZER((name).rwsem), \
diff --git a/include/linux/pid.h b/include/linux/pid.h
index 34afff2dc..514dd026c 100644
--- a/include/linux/pid.h
+++ b/include/linux/pid.h
@@ -3,6 +3,7 @@
#define _LINUX_PID_H
#include <linux/rculist.h>
+#include <linux/atomic.h>
#include <linux/wait.h>
#include <linux/refcount.h>
diff --git a/include/linux/preempt.h b/include/linux/preempt.h
index 89d5281e0..0386dd2ab 100644
--- a/include/linux/preempt.h
+++ b/include/linux/preempt.h
@@ -77,31 +77,37 @@
/* preempt_count() and related functions, depends on PREEMPT_NEED_RESCHED */
#include <asm/preempt.h>
+#define nmi_count() (preempt_count() & NMI_MASK)
#define hardirq_count() (preempt_count() & HARDIRQ_MASK)
-#define softirq_count() (preempt_count() & SOFTIRQ_MASK)
-#define irq_count() (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK \
- | NMI_MASK))
+#ifdef CONFIG_PREEMPT_RT
+# define softirq_count() (current->softirq_disable_cnt & SOFTIRQ_MASK)
+#else
+# define softirq_count() (preempt_count() & SOFTIRQ_MASK)
+#endif
+#define irq_count() (nmi_count() | hardirq_count() | softirq_count())
/*
- * Are we doing bottom half or hardware interrupt processing?
+ * Macros to retrieve the current execution context:
*
- * in_irq() - We're in (hard) IRQ context
+ * in_nmi() - We're in NMI context
+ * in_hardirq() - We're in hard IRQ context
+ * in_serving_softirq() - We're in softirq context
+ * in_task() - We're in task context
+ */
+#define in_nmi() (nmi_count())
+#define in_hardirq() (hardirq_count())
+#define in_serving_softirq() (softirq_count() & SOFTIRQ_OFFSET)
+#define in_task() (!(in_nmi() | in_hardirq() | in_serving_softirq()))
+
+/*
+ * The following macros are deprecated and should not be used in new code:
+ * in_irq() - Obsolete version of in_hardirq()
* in_softirq() - We have BH disabled, or are processing softirqs
* in_interrupt() - We're in NMI,IRQ,SoftIRQ context or have BH disabled
- * in_serving_softirq() - We're in softirq context
- * in_nmi() - We're in NMI context
- * in_task() - We're in task context
- *
- * Note: due to the BH disabled confusion: in_softirq(),in_interrupt() really
- * should not be used in new code.
*/
#define in_irq() (hardirq_count())
#define in_softirq() (softirq_count())
#define in_interrupt() (irq_count())
-#define in_serving_softirq() (softirq_count() & SOFTIRQ_OFFSET)
-#define in_nmi() (preempt_count() & NMI_MASK)
-#define in_task() (!(preempt_count() & \
- (NMI_MASK | HARDIRQ_MASK | SOFTIRQ_OFFSET)))
/*
* The preempt_count offset after preempt_disable();
@@ -115,7 +121,11 @@
/*
* The preempt_count offset after spin_lock()
*/
+#if !defined(CONFIG_PREEMPT_RT)
#define PREEMPT_LOCK_OFFSET PREEMPT_DISABLE_OFFSET
+#else
+#define PREEMPT_LOCK_OFFSET 0
+#endif
/*
* The preempt_count offset needed for things like:
@@ -164,6 +174,20 @@ extern void preempt_count_sub(int val);
#define preempt_count_inc() preempt_count_add(1)
#define preempt_count_dec() preempt_count_sub(1)
+#ifdef CONFIG_PREEMPT_LAZY
+#define add_preempt_lazy_count(val) do { preempt_lazy_count() += (val); } while (0)
+#define sub_preempt_lazy_count(val) do { preempt_lazy_count() -= (val); } while (0)
+#define inc_preempt_lazy_count() add_preempt_lazy_count(1)
+#define dec_preempt_lazy_count() sub_preempt_lazy_count(1)
+#define preempt_lazy_count() (current_thread_info()->preempt_lazy_count)
+#else
+#define add_preempt_lazy_count(val) do { } while (0)
+#define sub_preempt_lazy_count(val) do { } while (0)
+#define inc_preempt_lazy_count() do { } while (0)
+#define dec_preempt_lazy_count() do { } while (0)
+#define preempt_lazy_count() (0)
+#endif
+
#ifdef CONFIG_PREEMPT_COUNT
#define preempt_disable() \
@@ -172,13 +196,25 @@ do { \
barrier(); \
} while (0)
+#define preempt_lazy_disable() \
+do { \
+ inc_preempt_lazy_count(); \
+ barrier(); \
+} while (0)
+
#define sched_preempt_enable_no_resched() \
do { \
barrier(); \
preempt_count_dec(); \
} while (0)
-#define preempt_enable_no_resched() sched_preempt_enable_no_resched()
+#ifndef CONFIG_PREEMPT_RT
+# define preempt_enable_no_resched() sched_preempt_enable_no_resched()
+# define preempt_check_resched_rt() barrier();
+#else
+# define preempt_enable_no_resched() preempt_enable()
+# define preempt_check_resched_rt() preempt_check_resched()
+#endif
#define preemptible() (preempt_count() == 0 && !irqs_disabled())
@@ -203,6 +239,18 @@ do { \
__preempt_schedule(); \
} while (0)
+/*
+ * open code preempt_check_resched() because it is not exported to modules and
+ * used by local_unlock() or bpf_enable_instrumentation().
+ */
+#define preempt_lazy_enable() \
+do { \
+ dec_preempt_lazy_count(); \
+ barrier(); \
+ if (should_resched(0)) \
+ __preempt_schedule(); \
+} while (0)
+
#else /* !CONFIG_PREEMPTION */
#define preempt_enable() \
do { \
@@ -210,6 +258,12 @@ do { \
preempt_count_dec(); \
} while (0)
+#define preempt_lazy_enable() \
+do { \
+ dec_preempt_lazy_count(); \
+ barrier(); \
+} while (0)
+
#define preempt_enable_notrace() \
do { \
barrier(); \
@@ -248,8 +302,12 @@ do { \
#define preempt_disable_notrace() barrier()
#define preempt_enable_no_resched_notrace() barrier()
#define preempt_enable_notrace() barrier()
+#define preempt_check_resched_rt() barrier()
#define preemptible() 0
+#define preempt_lazy_disable() barrier()
+#define preempt_lazy_enable() barrier()
+
#endif /* CONFIG_PREEMPT_COUNT */
#ifdef MODULE
@@ -268,10 +326,22 @@ do { \
} while (0)
#define preempt_fold_need_resched() \
do { \
- if (tif_need_resched()) \
+ if (tif_need_resched_now()) \
set_preempt_need_resched(); \
} while (0)
+#ifdef CONFIG_PREEMPT_RT
+# define preempt_disable_rt() preempt_disable()
+# define preempt_enable_rt() preempt_enable()
+# define preempt_disable_nort() barrier()
+# define preempt_enable_nort() barrier()
+#else
+# define preempt_disable_rt() barrier()
+# define preempt_enable_rt() barrier()
+# define preempt_disable_nort() preempt_disable()
+# define preempt_enable_nort() preempt_enable()
+#endif
+
#ifdef CONFIG_PREEMPT_NOTIFIERS
struct preempt_notifier;
@@ -322,36 +392,82 @@ static inline void preempt_notifier_init(struct preempt_notifier *notifier,
#endif
-/**
- * migrate_disable - Prevent migration of the current task
+
+#ifdef CONFIG_SMP
+
+/*
+ * Migrate-Disable and why it is undesired.
*
- * Maps to preempt_disable() which also disables preemption. Use
- * migrate_disable() to annotate that the intent is to prevent migration,
- * but not necessarily preemption.
+ * When a preempted task becomes elegible to run under the ideal model (IOW it
+ * becomes one of the M highest priority tasks), it might still have to wait
+ * for the preemptee's migrate_disable() section to complete. Thereby suffering
+ * a reduction in bandwidth in the exact duration of the migrate_disable()
+ * section.
*
- * Can be invoked nested like preempt_disable() and needs the corresponding
- * number of migrate_enable() invocations.
- */
-static __always_inline void migrate_disable(void)
-{
- preempt_disable();
-}
-
-/**
* migrate_enable - Allow migration of the current task
+ * Per this argument, the change from preempt_disable() to migrate_disable()
+ * gets us:
*
- * Counterpart to migrate_disable().
+ * - a higher priority tasks gains reduced wake-up latency; with preempt_disable()
+ * it would have had to wait for the lower priority task.
*
- * As migrate_disable() can be invoked nested, only the outermost invocation
- * reenables migration.
+ * - a lower priority tasks; which under preempt_disable() could've instantly
+ * migrated away when another CPU becomes available, is now constrained
+ * by the ability to push the higher priority task away, which might itself be
+ * in a migrate_disable() section, reducing it's available bandwidth.
*
- * Currently mapped to preempt_enable().
- */
-static __always_inline void migrate_enable(void)
+ * IOW it trades latency / moves the interference term, but it stays in the
+ * system, and as long as it remains unbounded, the system is not fully
+ * deterministic.
+ *
+ * The reason we have it anyway.
+ *
+ * PREEMPT_RT breaks a number of assumptions traditionally held. By forcing a
+ * number of primitives into becoming preemptible, they would also allow
+ * migration. This turns out to break a bunch of per-cpu usage. To this end,
+ * all these primitives employ migirate_disable() to restore this implicit
+ * assumption.
+ *
+ * This is a 'temporary' work-around at best. The correct solution is getting
+ * rid of the above assumptions and reworking the code to employ explicit
+ * per-cpu locking or short preempt-disable regions.
+ *
+ * The end goal must be to get rid of migrate_disable(), alternatively we need
+ * a schedulability theory that does not depend on abritrary migration.
+ *
+ *
+ * Notes on the implementation.
+ *
+ * The implementation is particularly tricky since existing code patterns
+ * dictate neither migrate_disable() nor migrate_enable() is allowed to block.
+ * This means that it cannot use cpus_read_lock() to serialize against hotplug,
+ * nor can it easily migrate itself into a pending affinity mask change on
+ * migrate_enable().
+ *
+ *
+ * Note: even non-work-conserving schedulers like semi-partitioned depends on
+ * migration, so migrate_disable() is not only a problem for
+ * work-conserving schedulers.
+ *
+*/
+
+extern void migrate_disable(void);
+extern void migrate_enable(void);
+
+#else
+
+static inline void migrate_disable(void)
{
- preempt_enable();
+ preempt_lazy_disable();
}
+static inline void migrate_enable(void)
+{
+ preempt_lazy_enable();
+}
+
+#endif /* CONFIG_SMP */
+
int in_dbg(void);
#endif /* __LINUX_PREEMPT_H */
diff --git a/include/linux/printk.h b/include/linux/printk.h
index 9bd33432d..26c70fd11 100644
--- a/include/linux/printk.h
+++ b/include/linux/printk.h
@@ -46,6 +46,12 @@ static inline const char *printk_skip_headers(const char *buffer)
#define CONSOLE_EXT_LOG_MAX 8192
+/*
+ * The maximum size of a record formatted for console printing
+ * (i.e. with the prefix prepended to every line).
+ */
+#define CONSOLE_LOG_MAX 4096
+
/* printk's without a loglevel use this.. */
#define MESSAGE_LOGLEVEL_DEFAULT CONFIG_MESSAGE_LOGLEVEL_DEFAULT
@@ -149,18 +155,6 @@ static inline __printf(1, 2) __cold
void early_printk(const char *s, ...) { }
#endif
-#ifdef CONFIG_PRINTK_NMI
-extern void printk_nmi_enter(void);
-extern void printk_nmi_exit(void);
-extern void printk_nmi_direct_enter(void);
-extern void printk_nmi_direct_exit(void);
-#else
-static inline void printk_nmi_enter(void) { }
-static inline void printk_nmi_exit(void) { }
-static inline void printk_nmi_direct_enter(void) { }
-static inline void printk_nmi_direct_exit(void) { }
-#endif /* PRINTK_NMI */
-
#ifdef CONFIG_PRINTK
extern void printk_safe_enter(void);
extern void printk_safe_exit(void);
@@ -247,8 +241,6 @@ __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...);
void dump_stack_print_info(const char *log_lvl);
void show_regs_print_info(const char *log_lvl);
extern asmlinkage void dump_stack(void) __cold;
-extern void printk_safe_flush(void);
-extern void printk_safe_flush_on_panic(void);
#if defined(CONFIG_X86) || defined(CONFIG_ARM64_PSEUDO_NMI)
extern void zap_locks(void);
#else
@@ -318,14 +310,6 @@ static inline void dump_stack(void)
{
}
-static inline void printk_safe_flush(void)
-{
-}
-
-static inline void printk_safe_flush_on_panic(void)
-{
-}
-
static inline void zap_locks(void)
{
}
@@ -546,6 +530,8 @@ extern int kptr_restrict;
no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
#endif
+bool pr_flush(int timeout_ms, bool reset_on_progress);
+
/*
* ratelimited messages with local ratelimit_state,
* no local ratelimit_state used in the !PRINTK case
diff --git a/include/linux/rbtree.h b/include/linux/rbtree.h
index d31ecaf4f..e711efc2e 100644
--- a/include/linux/rbtree.h
+++ b/include/linux/rbtree.h
@@ -19,19 +19,9 @@
#include <linux/kernel.h>
#include <linux/stddef.h>
+#include <linux/rbtree_type.h>
#include <linux/rcupdate.h>
-struct rb_node {
- unsigned long __rb_parent_color;
- struct rb_node *rb_right;
- struct rb_node *rb_left;
-} __attribute__((aligned(sizeof(long))));
- /* The alignment might seem pointless, but allegedly CRIS needs it */
-
-struct rb_root {
- struct rb_node *rb_node;
-};
-
#define rb_parent(r) ((struct rb_node *)((r)->__rb_parent_color & ~3))
#define RB_ROOT (struct rb_root) { NULL, }
@@ -112,21 +102,6 @@ static inline void rb_link_node_rcu(struct rb_node *node, struct rb_node *parent
typeof(*pos), field); 1; }); \
pos = n)
-/*
- * Leftmost-cached rbtrees.
- *
- * We do not cache the rightmost node based on footprint
- * size vs number of potential users that could benefit
- * from O(1) rb_last(). Just not worth it, users that want
- * this feature can always implement the logic explicitly.
- * Furthermore, users that want to cache both pointers may
- * find it a bit asymmetric, but that's ok.
- */
-struct rb_root_cached {
- struct rb_root rb_root;
- struct rb_node *rb_leftmost;
-};
-
#define RB_ROOT_CACHED (struct rb_root_cached) { {NULL, }, NULL }
/* Same as rb_first(), but O(1) */
diff --git a/include/linux/rbtree_type.h b/include/linux/rbtree_type.h
new file mode 100644
index 000000000..77a89dd2c
--- /dev/null
+++ b/include/linux/rbtree_type.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _LINUX_RBTREE_TYPE_H
+#define _LINUX_RBTREE_TYPE_H
+
+struct rb_node {
+ unsigned long __rb_parent_color;
+ struct rb_node *rb_right;
+ struct rb_node *rb_left;
+} __attribute__((aligned(sizeof(long))));
+/* The alignment might seem pointless, but allegedly CRIS needs it */
+
+struct rb_root {
+ struct rb_node *rb_node;
+};
+
+/*
+ * Leftmost-cached rbtrees.
+ *
+ * We do not cache the rightmost node based on footprint
+ * size vs number of potential users that could benefit
+ * from O(1) rb_last(). Just not worth it, users that want
+ * this feature can always implement the logic explicitly.
+ * Furthermore, users that want to cache both pointers may
+ * find it a bit asymmetric, but that's ok.
+ */
+struct rb_root_cached {
+ struct rb_root rb_root;
+ struct rb_node *rb_leftmost;
+};
+
+#endif
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
index 8716a1706..23f5f07f1 100644
--- a/include/linux/rcupdate.h
+++ b/include/linux/rcupdate.h
@@ -54,6 +54,11 @@ void __rcu_read_unlock(void);
* types of kernel builds, the rcu_read_lock() nesting depth is unknowable.
*/
#define rcu_preempt_depth() (current->rcu_read_lock_nesting)
+#ifndef CONFIG_PREEMPT_RT
+#define sched_rcu_preempt_depth() rcu_preempt_depth()
+#else
+static inline int sched_rcu_preempt_depth(void) { return 0; }
+#endif
#else /* #ifdef CONFIG_PREEMPT_RCU */
@@ -79,6 +84,8 @@ static inline int rcu_preempt_depth(void)
return 0;
}
+#define sched_rcu_preempt_depth() rcu_preempt_depth()
+
#endif /* #else #ifdef CONFIG_PREEMPT_RCU */
/* Internal to kernel */
@@ -338,7 +345,8 @@ static inline void rcu_preempt_sleep_check(void) { }
#define rcu_sleep_check() \
do { \
rcu_preempt_sleep_check(); \
- RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map), \
+ if (!IS_ENABLED(CONFIG_PREEMPT_RT)) \
+ RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map), \
"Illegal context switch in RCU-bh read-side critical section"); \
RCU_LOCKDEP_WARN(lock_is_held(&rcu_sched_lock_map), \
"Illegal context switch in RCU-sched read-side critical section"); \
diff --git a/include/linux/rtmutex.h b/include/linux/rtmutex.h
index 6fd615a0e..b02009f53 100644
--- a/include/linux/rtmutex.h
+++ b/include/linux/rtmutex.h
@@ -14,11 +14,15 @@
#define __LINUX_RT_MUTEX_H
#include <linux/linkage.h>
-#include <linux/rbtree.h>
-#include <linux/spinlock_types.h>
+#include <linux/rbtree_type.h>
+#include <linux/spinlock_types_raw.h>
extern int max_lock_depth; /* for sysctl */
+#ifdef CONFIG_DEBUG_MUTEXES
+#include <linux/debug_locks.h>
+#endif
+
/**
* The rt_mutex structure
*
@@ -31,12 +35,7 @@ struct rt_mutex {
raw_spinlock_t wait_lock;
struct rb_root_cached waiters;
struct task_struct *owner;
-#ifdef CONFIG_DEBUG_RT_MUTEXES
int save_state;
- const char *name, *file;
- int line;
- void *magic;
-#endif
#ifdef CONFIG_DEBUG_LOCK_ALLOC
struct lockdep_map dep_map;
#endif
@@ -49,6 +48,7 @@ struct hrtimer_sleeper;
extern int rt_mutex_debug_check_no_locks_freed(const void *from,
unsigned long len);
extern void rt_mutex_debug_check_no_locks_held(struct task_struct *task);
+ extern void rt_mutex_debug_task_free(struct task_struct *tsk);
#else
static inline int rt_mutex_debug_check_no_locks_freed(const void *from,
unsigned long len)
@@ -56,25 +56,15 @@ struct hrtimer_sleeper;
return 0;
}
# define rt_mutex_debug_check_no_locks_held(task) do { } while (0)
+# define rt_mutex_debug_task_free(t) do { } while (0)
#endif
-#ifdef CONFIG_DEBUG_RT_MUTEXES
-# define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) \
- , .name = #mutexname, .file = __FILE__, .line = __LINE__
-
-# define rt_mutex_init(mutex) \
+#define rt_mutex_init(mutex) \
do { \
static struct lock_class_key __key; \
__rt_mutex_init(mutex, __func__, &__key); \
} while (0)
- extern void rt_mutex_debug_task_free(struct task_struct *tsk);
-#else
-# define __DEBUG_RT_MUTEX_INITIALIZER(mutexname)
-# define rt_mutex_init(mutex) __rt_mutex_init(mutex, NULL, NULL)
-# define rt_mutex_debug_task_free(t) do { } while (0)
-#endif
-
#ifdef CONFIG_DEBUG_LOCK_ALLOC
#define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname) \
, .dep_map = { .name = #mutexname }
@@ -82,12 +72,19 @@ do { \
#define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)
#endif
-#define __RT_MUTEX_INITIALIZER(mutexname) \
- { .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \
+#define __RT_MUTEX_INITIALIZER_PLAIN(mutexname) \
+ .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \
, .waiters = RB_ROOT_CACHED \
, .owner = NULL \
- __DEBUG_RT_MUTEX_INITIALIZER(mutexname) \
- __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)}
+ __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)
+
+#define __RT_MUTEX_INITIALIZER(mutexname) \
+ { __RT_MUTEX_INITIALIZER_PLAIN(mutexname) \
+ , .save_state = 0 }
+
+#define __RT_MUTEX_INITIALIZER_SAVE_STATE(mutexname) \
+ { __RT_MUTEX_INITIALIZER_PLAIN(mutexname) \
+ , .save_state = 1 }
#define DEFINE_RT_MUTEX(mutexname) \
struct rt_mutex mutexname = __RT_MUTEX_INITIALIZER(mutexname)
@@ -115,9 +112,6 @@ extern void rt_mutex_lock(struct rt_mutex *lock);
#endif
extern int rt_mutex_lock_interruptible(struct rt_mutex *lock);
-extern int rt_mutex_timed_lock(struct rt_mutex *lock,
- struct hrtimer_sleeper *timeout);
-
extern int rt_mutex_trylock(struct rt_mutex *lock);
extern void rt_mutex_unlock(struct rt_mutex *lock);
diff --git a/include/linux/rwlock_rt.h b/include/linux/rwlock_rt.h
new file mode 100644
index 000000000..aafdb0a68
--- /dev/null
+++ b/include/linux/rwlock_rt.h
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef __LINUX_RWLOCK_RT_H
+#define __LINUX_RWLOCK_RT_H
+
+#ifndef __LINUX_SPINLOCK_H
+#error Do not include directly. Use spinlock.h
+#endif
+
+extern void __lockfunc rt_write_lock(rwlock_t *rwlock);
+extern void __lockfunc rt_read_lock(rwlock_t *rwlock);
+extern int __lockfunc rt_write_trylock(rwlock_t *rwlock);
+extern int __lockfunc rt_read_trylock(rwlock_t *rwlock);
+extern void __lockfunc rt_write_unlock(rwlock_t *rwlock);
+extern void __lockfunc rt_read_unlock(rwlock_t *rwlock);
+extern int __lockfunc rt_read_can_lock(rwlock_t *rwlock);
+extern int __lockfunc rt_write_can_lock(rwlock_t *rwlock);
+extern void __rt_rwlock_init(rwlock_t *rwlock, char *name, struct lock_class_key *key);
+
+#define read_can_lock(rwlock) rt_read_can_lock(rwlock)
+#define write_can_lock(rwlock) rt_write_can_lock(rwlock)
+
+#define read_trylock(lock) __cond_lock(lock, rt_read_trylock(lock))
+#define write_trylock(lock) __cond_lock(lock, rt_write_trylock(lock))
+
+static inline int __write_trylock_rt_irqsave(rwlock_t *lock, unsigned long *flags)
+{
+ *flags = 0;
+ return rt_write_trylock(lock);
+}
+
+#define write_trylock_irqsave(lock, flags) \
+ __cond_lock(lock, __write_trylock_rt_irqsave(lock, &(flags)))
+
+#define read_lock_irqsave(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ rt_read_lock(lock); \
+ flags = 0; \
+ } while (0)
+
+#define write_lock_irqsave(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ rt_write_lock(lock); \
+ flags = 0; \
+ } while (0)
+
+#define read_lock(lock) rt_read_lock(lock)
+
+#define read_lock_bh(lock) \
+ do { \
+ local_bh_disable(); \
+ rt_read_lock(lock); \
+ } while (0)
+
+#define read_lock_irq(lock) read_lock(lock)
+
+#define write_lock(lock) rt_write_lock(lock)
+
+#define write_lock_bh(lock) \
+ do { \
+ local_bh_disable(); \
+ rt_write_lock(lock); \
+ } while (0)
+
+#define write_lock_irq(lock) write_lock(lock)
+
+#define read_unlock(lock) rt_read_unlock(lock)
+
+#define read_unlock_bh(lock) \
+ do { \
+ rt_read_unlock(lock); \
+ local_bh_enable(); \
+ } while (0)
+
+#define read_unlock_irq(lock) read_unlock(lock)
+
+#define write_unlock(lock) rt_write_unlock(lock)
+
+#define write_unlock_bh(lock) \
+ do { \
+ rt_write_unlock(lock); \
+ local_bh_enable(); \
+ } while (0)
+
+#define write_unlock_irq(lock) write_unlock(lock)
+
+#define read_unlock_irqrestore(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ (void) flags; \
+ rt_read_unlock(lock); \
+ } while (0)
+
+#define write_unlock_irqrestore(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ (void) flags; \
+ rt_write_unlock(lock); \
+ } while (0)
+
+#define rwlock_init(rwl) \
+do { \
+ static struct lock_class_key __key; \
+ \
+ __rt_rwlock_init(rwl, #rwl, &__key); \
+} while (0)
+
+#endif
diff --git a/include/linux/rwlock_types.h b/include/linux/rwlock_types.h
index 3bd03e180..0ad226b5d 100644
--- a/include/linux/rwlock_types.h
+++ b/include/linux/rwlock_types.h
@@ -1,6 +1,10 @@
#ifndef __LINUX_RWLOCK_TYPES_H
#define __LINUX_RWLOCK_TYPES_H
+#if !defined(__LINUX_SPINLOCK_TYPES_H)
+# error "Do not include directly, include spinlock_types.h"
+#endif
+
/*
* include/linux/rwlock_types.h - generic rwlock type definitions
* and initializers
diff --git a/include/linux/rwlock_types_rt.h b/include/linux/rwlock_types_rt.h
new file mode 100644
index 000000000..4762391d6
--- /dev/null
+++ b/include/linux/rwlock_types_rt.h
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef __LINUX_RWLOCK_TYPES_RT_H
+#define __LINUX_RWLOCK_TYPES_RT_H
+
+#ifndef __LINUX_SPINLOCK_TYPES_H
+#error "Do not include directly. Include spinlock_types.h instead"
+#endif
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define RW_DEP_MAP_INIT(lockname) .dep_map = { .name = #lockname }
+#else
+# define RW_DEP_MAP_INIT(lockname)
+#endif
+
+typedef struct rt_rw_lock rwlock_t;
+
+#define __RW_LOCK_UNLOCKED(name) __RWLOCK_RT_INITIALIZER(name)
+
+#define DEFINE_RWLOCK(name) \
+ rwlock_t name = __RW_LOCK_UNLOCKED(name)
+
+/*
+ * A reader biased implementation primarily for CPU pinning.
+ *
+ * Can be selected as general replacement for the single reader RT rwlock
+ * variant
+ */
+struct rt_rw_lock {
+ struct rt_mutex rtmutex;
+ atomic_t readers;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif
+};
+
+#define READER_BIAS (1U << 31)
+#define WRITER_BIAS (1U << 30)
+
+#define __RWLOCK_RT_INITIALIZER(name) \
+{ \
+ .readers = ATOMIC_INIT(READER_BIAS), \
+ .rtmutex = __RT_MUTEX_INITIALIZER_SAVE_STATE(name.rtmutex), \
+ RW_DEP_MAP_INIT(name) \
+}
+
+void __rwlock_biased_rt_init(struct rt_rw_lock *lock, const char *name,
+ struct lock_class_key *key);
+
+#define rwlock_biased_rt_init(rwlock) \
+ do { \
+ static struct lock_class_key __key; \
+ \
+ __rwlock_biased_rt_init((rwlock), #rwlock, &__key); \
+ } while (0)
+
+#endif
diff --git a/include/linux/rwsem-rt.h b/include/linux/rwsem-rt.h
new file mode 100644
index 000000000..0ba8aae9a
--- /dev/null
+++ b/include/linux/rwsem-rt.h
@@ -0,0 +1,70 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef _LINUX_RWSEM_RT_H
+#define _LINUX_RWSEM_RT_H
+
+#ifndef _LINUX_RWSEM_H
+#error "Include rwsem.h"
+#endif
+
+#include <linux/rtmutex.h>
+#include <linux/swait.h>
+
+#define READER_BIAS (1U << 31)
+#define WRITER_BIAS (1U << 30)
+
+struct rw_semaphore {
+ atomic_t readers;
+ struct rt_mutex rtmutex;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif
+};
+
+#define __RWSEM_INITIALIZER(name) \
+{ \
+ .readers = ATOMIC_INIT(READER_BIAS), \
+ .rtmutex = __RT_MUTEX_INITIALIZER(name.rtmutex), \
+ RW_DEP_MAP_INIT(name) \
+}
+
+#define DECLARE_RWSEM(lockname) \
+ struct rw_semaphore lockname = __RWSEM_INITIALIZER(lockname)
+
+extern void __rwsem_init(struct rw_semaphore *rwsem, const char *name,
+ struct lock_class_key *key);
+
+#define __init_rwsem(sem, name, key) \
+do { \
+ rt_mutex_init(&(sem)->rtmutex); \
+ __rwsem_init((sem), (name), (key)); \
+} while (0)
+
+#define init_rwsem(sem) \
+do { \
+ static struct lock_class_key __key; \
+ \
+ __init_rwsem((sem), #sem, &__key); \
+} while (0)
+
+static inline int rwsem_is_locked(struct rw_semaphore *sem)
+{
+ return atomic_read(&sem->readers) != READER_BIAS;
+}
+
+static inline int rwsem_is_contended(struct rw_semaphore *sem)
+{
+ return atomic_read(&sem->readers) > 0;
+}
+
+extern void __down_read(struct rw_semaphore *sem);
+extern int __down_read_interruptible(struct rw_semaphore *sem);
+extern int __down_read_killable(struct rw_semaphore *sem);
+extern int __down_read_trylock(struct rw_semaphore *sem);
+extern void __down_write(struct rw_semaphore *sem);
+extern int __must_check __down_write_killable(struct rw_semaphore *sem);
+extern int __down_write_trylock(struct rw_semaphore *sem);
+extern void __up_read(struct rw_semaphore *sem);
+extern void __up_write(struct rw_semaphore *sem);
+extern void __downgrade_write(struct rw_semaphore *sem);
+
+#endif
diff --git a/include/linux/rwsem.h b/include/linux/rwsem.h
index 4c715be48..9323af8a9 100644
--- a/include/linux/rwsem.h
+++ b/include/linux/rwsem.h
@@ -16,6 +16,11 @@
#include <linux/spinlock.h>
#include <linux/atomic.h>
#include <linux/err.h>
+
+#ifdef CONFIG_PREEMPT_RT
+#include <linux/rwsem-rt.h>
+#else /* PREEMPT_RT */
+
#ifdef CONFIG_RWSEM_SPIN_ON_OWNER
#include <linux/osq_lock.h>
#endif
@@ -119,6 +124,13 @@ static inline int rwsem_is_contended(struct rw_semaphore *sem)
return !list_empty(&sem->wait_list);
}
+#endif /* !PREEMPT_RT */
+
+/*
+ * The functions below are the same for all rwsem implementations including
+ * the RT specific variant.
+ */
+
/*
* lock for reading
*/
diff --git a/include/linux/sched.h b/include/linux/sched.h
index e3170b7f8..6c5c484fe 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -36,6 +36,7 @@
#include <linux/kcsan.h>
#include <linux/thread_bits.h>
#include <linux/kabi.h>
+#include <asm/kmap_size.h>
/* task_struct member predeclarations (sorted alphabetically): */
struct audit_context;
@@ -114,12 +115,8 @@ struct io_uring_task;
__TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
TASK_PARKED)
-#define task_is_traced(task) ((task->state & __TASK_TRACED) != 0)
-
#define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0)
-#define task_is_stopped_or_traced(task) ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
-
#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
/*
@@ -143,6 +140,9 @@ struct io_uring_task;
smp_store_mb(current->state, (state_value)); \
} while (0)
+#define __set_current_state_no_track(state_value) \
+ current->state = (state_value);
+
#define set_special_state(state_value) \
do { \
unsigned long flags; /* may shadow */ \
@@ -196,6 +196,9 @@ struct io_uring_task;
#define set_current_state(state_value) \
smp_store_mb(current->state, (state_value))
+#define __set_current_state_no_track(state_value) \
+ __set_current_state(state_value)
+
/*
* set_special_state() should be used for those states when the blocking task
* can not use the regular condition based wait-loop. In that case we must
@@ -683,6 +686,13 @@ struct wake_q_node {
struct wake_q_node *next;
};
+struct kmap_ctrl {
+#ifdef CONFIG_KMAP_LOCAL
+ int idx;
+ pte_t pteval[KM_MAX_IDX];
+#endif
+};
+
/**
* struct task_struct_resvd - KABI extension struct
*/
@@ -708,6 +718,8 @@ struct task_struct {
#endif
/* -1 unrunnable, 0 runnable, >0 stopped: */
volatile long state;
+ /* saved state for "spinlock sleepers" */
+ volatile long saved_state;
/*
* This begins the randomizable portion of task_struct. Only
@@ -780,6 +792,11 @@ struct task_struct {
int nr_cpus_allowed;
const cpumask_t *cpus_ptr;
cpumask_t cpus_mask;
+ void *migration_pending;
+#ifdef CONFIG_SMP
+ unsigned short migration_disabled;
+#endif
+ unsigned short migration_flags;
#ifdef CONFIG_PREEMPT_RCU
int rcu_read_lock_nesting;
@@ -888,6 +905,10 @@ struct task_struct {
#ifdef CONFIG_IOMMU_SVA
KABI_FILL_HOLE(unsigned pasid_activated:1)
#endif
+#ifdef CONFIG_EVENTFD
+ /* Recursion prevention for eventfd_signal() */
+ unsigned in_eventfd_signal:1;
+#endif
unsigned long atomic_flags; /* Flags requiring atomic access. */
@@ -1029,11 +1050,16 @@ struct task_struct {
/* Signal handlers: */
struct signal_struct *signal;
struct sighand_struct __rcu *sighand;
+ struct sigqueue *sigqueue_cache;
sigset_t blocked;
sigset_t real_blocked;
/* Restored if set_restore_sigmask() was used: */
sigset_t saved_sigmask;
struct sigpending pending;
+#ifdef CONFIG_PREEMPT_RT
+ /* TODO: move me into ->restart_block ? */
+ struct kernel_siginfo forced_info;
+#endif
unsigned long sas_ss_sp;
size_t sas_ss_size;
unsigned int sas_ss_flags;
@@ -1060,6 +1086,7 @@ struct task_struct {
raw_spinlock_t pi_lock;
struct wake_q_node wake_q;
+ struct wake_q_node wake_q_sleeper;
#ifdef CONFIG_RT_MUTEXES
/* PI waiters blocked on a rt_mutex held by this task: */
@@ -1087,6 +1114,9 @@ struct task_struct {
int softirq_context;
int irq_config;
#endif
+#ifdef CONFIG_PREEMPT_RT
+ int softirq_disable_cnt;
+#endif
#ifdef CONFIG_LOCKDEP
# define MAX_LOCK_DEPTH 48UL
@@ -1372,6 +1402,7 @@ struct task_struct {
unsigned int sequential_io;
unsigned int sequential_io_avg;
#endif
+ struct kmap_ctrl kmap_ctrl;
#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
unsigned long task_state_change;
#endif
@@ -1882,6 +1913,7 @@ extern struct task_struct *find_get_task_by_vpid(pid_t nr);
extern int wake_up_state(struct task_struct *tsk, unsigned int state);
extern int wake_up_process(struct task_struct *tsk);
+extern int wake_up_lock_sleeper(struct task_struct *tsk);
extern void wake_up_new_task(struct task_struct *tsk);
#ifdef CONFIG_SMP
@@ -1983,6 +2015,89 @@ static inline int test_tsk_need_resched(struct task_struct *tsk)
return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
}
+#ifdef CONFIG_PREEMPT_LAZY
+static inline void set_tsk_need_resched_lazy(struct task_struct *tsk)
+{
+ set_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY);
+}
+
+static inline void clear_tsk_need_resched_lazy(struct task_struct *tsk)
+{
+ clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY);
+}
+
+static inline int test_tsk_need_resched_lazy(struct task_struct *tsk)
+{
+ return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY));
+}
+
+static inline int need_resched_lazy(void)
+{
+ return test_thread_flag(TIF_NEED_RESCHED_LAZY);
+}
+
+static inline int need_resched_now(void)
+{
+ return test_thread_flag(TIF_NEED_RESCHED);
+}
+
+#else
+static inline void clear_tsk_need_resched_lazy(struct task_struct *tsk) { }
+static inline int need_resched_lazy(void) { return 0; }
+
+static inline int need_resched_now(void)
+{
+ return test_thread_flag(TIF_NEED_RESCHED);
+}
+
+#endif
+
+
+static inline bool __task_is_stopped_or_traced(struct task_struct *task)
+{
+ if (task->state & (__TASK_STOPPED | __TASK_TRACED))
+ return true;
+#ifdef CONFIG_PREEMPT_RT
+ if (task->saved_state & (__TASK_STOPPED | __TASK_TRACED))
+ return true;
+#endif
+ return false;
+}
+
+static inline bool task_is_stopped_or_traced(struct task_struct *task)
+{
+ bool traced_stopped;
+
+#ifdef CONFIG_PREEMPT_RT
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&task->pi_lock, flags);
+ traced_stopped = __task_is_stopped_or_traced(task);
+ raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+#else
+ traced_stopped = __task_is_stopped_or_traced(task);
+#endif
+ return traced_stopped;
+}
+
+static inline bool task_is_traced(struct task_struct *task)
+{
+ bool traced = false;
+
+ if (task->state & __TASK_TRACED)
+ return true;
+#ifdef CONFIG_PREEMPT_RT
+ /* in case the task is sleeping on tasklist_lock */
+ raw_spin_lock_irq(&task->pi_lock);
+ if (task->state & __TASK_TRACED)
+ traced = true;
+ else if (task->saved_state & __TASK_TRACED)
+ traced = true;
+ raw_spin_unlock_irq(&task->pi_lock);
+#endif
+ return traced;
+}
+
/*
* cond_resched() and cond_resched_lock(): latency reduction via
* explicit rescheduling in places that are safe. The return
@@ -2073,11 +2188,7 @@ static inline int spin_needbreak(spinlock_t *lock)
*/
static inline int rwlock_needbreak(rwlock_t *lock)
{
-#ifdef CONFIG_PREEMPTION
- return rwlock_is_contended(lock);
-#else
return 0;
-#endif
}
static __always_inline bool need_resched(void)
diff --git a/include/linux/sched/hotplug.h b/include/linux/sched/hotplug.h
index 9a62ffdd2..412cdaba3 100644
--- a/include/linux/sched/hotplug.h
+++ b/include/linux/sched/hotplug.h
@@ -11,8 +11,10 @@ extern int sched_cpu_activate(unsigned int cpu);
extern int sched_cpu_deactivate(unsigned int cpu);
#ifdef CONFIG_HOTPLUG_CPU
+extern int sched_cpu_wait_empty(unsigned int cpu);
extern int sched_cpu_dying(unsigned int cpu);
#else
+# define sched_cpu_wait_empty NULL
# define sched_cpu_dying NULL
#endif
diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h
index f58a2730a..5f4aa9842 100644
--- a/include/linux/sched/mm.h
+++ b/include/linux/sched/mm.h
@@ -50,6 +50,17 @@ static inline void mmdrop(struct mm_struct *mm)
__mmdrop(mm);
}
+#ifdef CONFIG_PREEMPT_RT
+extern void __mmdrop_delayed(struct rcu_head *rhp);
+static inline void mmdrop_delayed(struct mm_struct *mm)
+{
+ if (atomic_dec_and_test(&mm->mm_count))
+ call_rcu(&mm->delayed_drop, __mmdrop_delayed);
+}
+#else
+# define mmdrop_delayed(mm) mmdrop(mm)
+#endif
+
/**
* mmget() - Pin the address space associated with a &struct mm_struct.
* @mm: The address space to pin.
diff --git a/include/linux/sched/rt.h b/include/linux/sched/rt.h
index e5af028c0..994c25640 100644
--- a/include/linux/sched/rt.h
+++ b/include/linux/sched/rt.h
@@ -39,20 +39,12 @@ static inline struct task_struct *rt_mutex_get_top_task(struct task_struct *p)
}
extern void rt_mutex_setprio(struct task_struct *p, struct task_struct *pi_task);
extern void rt_mutex_adjust_pi(struct task_struct *p);
-static inline bool tsk_is_pi_blocked(struct task_struct *tsk)
-{
- return tsk->pi_blocked_on != NULL;
-}
#else
static inline struct task_struct *rt_mutex_get_top_task(struct task_struct *task)
{
return NULL;
}
# define rt_mutex_adjust_pi(p) do { } while (0)
-static inline bool tsk_is_pi_blocked(struct task_struct *tsk)
-{
- return false;
-}
#endif
extern void normalize_rt_tasks(void);
diff --git a/include/linux/sched/wake_q.h b/include/linux/sched/wake_q.h
index 26a2013ac..6e2dff721 100644
--- a/include/linux/sched/wake_q.h
+++ b/include/linux/sched/wake_q.h
@@ -58,6 +58,17 @@ static inline bool wake_q_empty(struct wake_q_head *head)
extern void wake_q_add(struct wake_q_head *head, struct task_struct *task);
extern void wake_q_add_safe(struct wake_q_head *head, struct task_struct *task);
-extern void wake_up_q(struct wake_q_head *head);
+extern void wake_q_add_sleeper(struct wake_q_head *head, struct task_struct *task);
+extern void __wake_up_q(struct wake_q_head *head, bool sleeper);
+
+static inline void wake_up_q(struct wake_q_head *head)
+{
+ __wake_up_q(head, false);
+}
+
+static inline void wake_up_q_sleeper(struct wake_q_head *head)
+{
+ __wake_up_q(head, true);
+}
#endif /* _LINUX_SCHED_WAKE_Q_H */
diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
index de6322f91..35589e8c5 100644
--- a/include/linux/serial_8250.h
+++ b/include/linux/serial_8250.h
@@ -7,6 +7,7 @@
#ifndef _LINUX_SERIAL_8250_H
#define _LINUX_SERIAL_8250_H
+#include <linux/atomic.h>
#include <linux/serial_core.h>
#include <linux/serial_reg.h>
#include <linux/platform_device.h>
@@ -125,6 +126,8 @@ struct uart_8250_port {
#define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
unsigned char msr_saved_flags;
+ atomic_t console_printing;
+
struct uart_8250_dma *dma;
const struct uart_8250_ops *ops;
@@ -180,6 +183,8 @@ void serial8250_init_port(struct uart_8250_port *up);
void serial8250_set_defaults(struct uart_8250_port *up);
void serial8250_console_write(struct uart_8250_port *up, const char *s,
unsigned int count);
+void serial8250_console_write_atomic(struct uart_8250_port *up, const char *s,
+ unsigned int count);
int serial8250_console_setup(struct uart_port *port, char *options, bool probe);
int serial8250_console_exit(struct uart_port *port);
diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
index 93240799a..df2871ed8 100644
--- a/include/linux/shmem_fs.h
+++ b/include/linux/shmem_fs.h
@@ -32,7 +32,7 @@ struct shmem_sb_info {
struct percpu_counter used_blocks; /* How many are allocated */
unsigned long max_inodes; /* How many inodes are allowed */
unsigned long free_inodes; /* How many are left for allocation */
- spinlock_t stat_lock; /* Serialize shmem_sb_info changes */
+ raw_spinlock_t stat_lock; /* Serialize shmem_sb_info changes */
umode_t mode; /* Mount mode for root directory */
unsigned char huge; /* Whether to try for hugepages */
kuid_t uid; /* Mount uid for root directory */
diff --git a/include/linux/signal.h b/include/linux/signal.h
index 3038a0610..fff1656c6 100644
--- a/include/linux/signal.h
+++ b/include/linux/signal.h
@@ -265,6 +265,7 @@ static inline void init_sigpending(struct sigpending *sig)
}
extern void flush_sigqueue(struct sigpending *queue);
+extern void flush_task_sigqueue(struct task_struct *tsk);
/* Test if 'sig' is valid signal. Use this instead of testing _NSIG directly */
static inline int valid_signal(unsigned long sig)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 4a7a2ff7a..116b3f6f8 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -299,6 +299,7 @@ struct sk_buff_head {
__u32 qlen;
spinlock_t lock;
+ raw_spinlock_t raw_lock;
};
struct sk_buff;
@@ -1938,6 +1939,12 @@ static inline void skb_queue_head_init(struct sk_buff_head *list)
__skb_queue_head_init(list);
}
+static inline void skb_queue_head_init_raw(struct sk_buff_head *list)
+{
+ raw_spin_lock_init(&list->raw_lock);
+ __skb_queue_head_init(list);
+}
+
static inline void skb_queue_head_init_class(struct sk_buff_head *list,
struct lock_class_key *class)
{
diff --git a/include/linux/smp.h b/include/linux/smp.h
index 812c26f61..dcf0b5d50 100644
--- a/include/linux/smp.h
+++ b/include/linux/smp.h
@@ -260,6 +260,9 @@ static inline int get_boot_cpu_id(void)
#define get_cpu() ({ preempt_disable(); __smp_processor_id(); })
#define put_cpu() preempt_enable()
+#define get_cpu_light() ({ migrate_disable(); __smp_processor_id(); })
+#define put_cpu_light() migrate_enable()
+
/*
* Callback to arch code if there's nosmp or maxcpus=0 on the
* boot command line:
diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
index 79897841a..c3c70291b 100644
--- a/include/linux/spinlock.h
+++ b/include/linux/spinlock.h
@@ -309,7 +309,11 @@ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
})
/* Include rwlock functions */
-#include <linux/rwlock.h>
+#ifdef CONFIG_PREEMPT_RT
+# include <linux/rwlock_rt.h>
+#else
+# include <linux/rwlock.h>
+#endif
/*
* Pull the _spin_*()/_read_*()/_write_*() functions/declarations:
@@ -320,6 +324,10 @@ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
# include <linux/spinlock_api_up.h>
#endif
+#ifdef CONFIG_PREEMPT_RT
+# include <linux/spinlock_rt.h>
+#else /* PREEMPT_RT */
+
/*
* Map the spin_lock functions to the raw variants for PREEMPT_RT=n
*/
@@ -454,6 +462,8 @@ static __always_inline int spin_is_contended(spinlock_t *lock)
#define assert_spin_locked(lock) assert_raw_spin_locked(&(lock)->rlock)
+#endif /* !PREEMPT_RT */
+
/*
* Pull the atomic_t declaration:
* (asm-mips/atomic.h needs above definitions)
diff --git a/include/linux/spinlock_api_smp.h b/include/linux/spinlock_api_smp.h
index 19a9be9d9..da38149f2 100644
--- a/include/linux/spinlock_api_smp.h
+++ b/include/linux/spinlock_api_smp.h
@@ -187,6 +187,8 @@ static inline int __raw_spin_trylock_bh(raw_spinlock_t *lock)
return 0;
}
-#include <linux/rwlock_api_smp.h>
+#ifndef CONFIG_PREEMPT_RT
+# include <linux/rwlock_api_smp.h>
+#endif
#endif /* __LINUX_SPINLOCK_API_SMP_H */
diff --git a/include/linux/spinlock_rt.h b/include/linux/spinlock_rt.h
new file mode 100644
index 000000000..3085132ea
--- /dev/null
+++ b/include/linux/spinlock_rt.h
@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef __LINUX_SPINLOCK_RT_H
+#define __LINUX_SPINLOCK_RT_H
+
+#ifndef __LINUX_SPINLOCK_H
+#error Do not include directly. Use spinlock.h
+#endif
+
+#include <linux/bug.h>
+
+extern void
+__rt_spin_lock_init(spinlock_t *lock, const char *name, struct lock_class_key *key);
+
+#define spin_lock_init(slock) \
+do { \
+ static struct lock_class_key __key; \
+ \
+ rt_mutex_init(&(slock)->lock); \
+ __rt_spin_lock_init(slock, #slock, &__key); \
+} while (0)
+
+extern void __lockfunc rt_spin_lock(spinlock_t *lock);
+extern void __lockfunc rt_spin_lock_nested(spinlock_t *lock, int subclass);
+extern void __lockfunc rt_spin_lock_nest_lock(spinlock_t *lock, struct lockdep_map *nest_lock);
+extern void __lockfunc rt_spin_unlock(spinlock_t *lock);
+extern void __lockfunc rt_spin_lock_unlock(spinlock_t *lock);
+extern int __lockfunc rt_spin_trylock_irqsave(spinlock_t *lock, unsigned long *flags);
+extern int __lockfunc rt_spin_trylock_bh(spinlock_t *lock);
+extern int __lockfunc rt_spin_trylock(spinlock_t *lock);
+extern int atomic_dec_and_spin_lock(atomic_t *atomic, spinlock_t *lock);
+
+/*
+ * lockdep-less calls, for derived types like rwlock:
+ * (for trylock they can use rt_mutex_trylock() directly.
+ * Migrate disable handling must be done at the call site.
+ */
+extern void __lockfunc __rt_spin_lock(struct rt_mutex *lock);
+extern void __lockfunc __rt_spin_trylock(struct rt_mutex *lock);
+extern void __lockfunc __rt_spin_unlock(struct rt_mutex *lock);
+
+#define spin_lock(lock) rt_spin_lock(lock)
+
+#define spin_lock_bh(lock) \
+ do { \
+ local_bh_disable(); \
+ rt_spin_lock(lock); \
+ } while (0)
+
+#define spin_lock_irq(lock) spin_lock(lock)
+
+#define spin_do_trylock(lock) __cond_lock(lock, rt_spin_trylock(lock))
+
+#define spin_trylock(lock) \
+({ \
+ int __locked; \
+ __locked = spin_do_trylock(lock); \
+ __locked; \
+})
+
+#ifdef CONFIG_LOCKDEP
+# define spin_lock_nested(lock, subclass) \
+ do { \
+ rt_spin_lock_nested(lock, subclass); \
+ } while (0)
+
+#define spin_lock_bh_nested(lock, subclass) \
+ do { \
+ local_bh_disable(); \
+ rt_spin_lock_nested(lock, subclass); \
+ } while (0)
+
+# define spin_lock_nest_lock(lock, subclass) \
+ do { \
+ typecheck(struct lockdep_map *, &(subclass)->dep_map); \
+ rt_spin_lock_nest_lock(lock, &(subclass)->dep_map); \
+ } while (0)
+
+# define spin_lock_irqsave_nested(lock, flags, subclass) \
+ do { \
+ typecheck(unsigned long, flags); \
+ flags = 0; \
+ rt_spin_lock_nested(lock, subclass); \
+ } while (0)
+#else
+# define spin_lock_nested(lock, subclass) spin_lock(((void)(subclass), (lock)))
+# define spin_lock_nest_lock(lock, subclass) spin_lock(((void)(subclass), (lock)))
+# define spin_lock_bh_nested(lock, subclass) spin_lock_bh(((void)(subclass), (lock)))
+
+# define spin_lock_irqsave_nested(lock, flags, subclass) \
+ do { \
+ typecheck(unsigned long, flags); \
+ flags = 0; \
+ spin_lock(((void)(subclass), (lock))); \
+ } while (0)
+#endif
+
+#define spin_lock_irqsave(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ flags = 0; \
+ spin_lock(lock); \
+ } while (0)
+
+#define spin_unlock(lock) rt_spin_unlock(lock)
+
+#define spin_unlock_bh(lock) \
+ do { \
+ rt_spin_unlock(lock); \
+ local_bh_enable(); \
+ } while (0)
+
+#define spin_unlock_irq(lock) spin_unlock(lock)
+
+#define spin_unlock_irqrestore(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ (void) flags; \
+ spin_unlock(lock); \
+ } while (0)
+
+#define spin_trylock_bh(lock) __cond_lock(lock, rt_spin_trylock_bh(lock))
+#define spin_trylock_irq(lock) spin_trylock(lock)
+
+#define spin_trylock_irqsave(lock, flags) \
+({ \
+ int __locked; \
+ \
+ typecheck(unsigned long, flags); \
+ flags = 0; \
+ __locked = spin_trylock(lock); \
+ __locked; \
+})
+
+#ifdef CONFIG_GENERIC_LOCKBREAK
+# define spin_is_contended(lock) ((lock)->break_lock)
+#else
+# define spin_is_contended(lock) (((void)(lock), 0))
+#endif
+
+static inline int spin_can_lock(spinlock_t *lock)
+{
+ return !rt_mutex_is_locked(&lock->lock);
+}
+
+static inline int spin_is_locked(spinlock_t *lock)
+{
+ return rt_mutex_is_locked(&lock->lock);
+}
+
+static inline void assert_spin_locked(spinlock_t *lock)
+{
+ BUG_ON(!spin_is_locked(lock));
+}
+
+#endif
diff --git a/include/linux/spinlock_types.h b/include/linux/spinlock_types.h
index b981caafe..8d896d3e1 100644
--- a/include/linux/spinlock_types.h
+++ b/include/linux/spinlock_types.h
@@ -9,93 +9,15 @@
* Released under the General Public License (GPL).
*/
-#if defined(CONFIG_SMP)
-# include <asm/spinlock_types.h>
-#else
-# include <linux/spinlock_types_up.h>
-#endif
-
-#include <linux/lockdep_types.h>
-
-typedef struct raw_spinlock {
- arch_spinlock_t raw_lock;
-#ifdef CONFIG_DEBUG_SPINLOCK
- unsigned int magic, owner_cpu;
- void *owner;
-#endif
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
- struct lockdep_map dep_map;
-#endif
-} raw_spinlock_t;
-
-#define SPINLOCK_MAGIC 0xdead4ead
-
-#define SPINLOCK_OWNER_INIT ((void *)-1L)
-
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define RAW_SPIN_DEP_MAP_INIT(lockname) \
- .dep_map = { \
- .name = #lockname, \
- .wait_type_inner = LD_WAIT_SPIN, \
- }
-# define SPIN_DEP_MAP_INIT(lockname) \
- .dep_map = { \
- .name = #lockname, \
- .wait_type_inner = LD_WAIT_CONFIG, \
- }
-#else
-# define RAW_SPIN_DEP_MAP_INIT(lockname)
-# define SPIN_DEP_MAP_INIT(lockname)
-#endif
+#include <linux/spinlock_types_raw.h>
-#ifdef CONFIG_DEBUG_SPINLOCK
-# define SPIN_DEBUG_INIT(lockname) \
- .magic = SPINLOCK_MAGIC, \
- .owner_cpu = -1, \
- .owner = SPINLOCK_OWNER_INIT,
+#ifndef CONFIG_PREEMPT_RT
+# include <linux/spinlock_types_nort.h>
+# include <linux/rwlock_types.h>
#else
-# define SPIN_DEBUG_INIT(lockname)
+# include <linux/rtmutex.h>
+# include <linux/spinlock_types_rt.h>
+# include <linux/rwlock_types_rt.h>
#endif
-#define __RAW_SPIN_LOCK_INITIALIZER(lockname) \
- { \
- .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED, \
- SPIN_DEBUG_INIT(lockname) \
- RAW_SPIN_DEP_MAP_INIT(lockname) }
-
-#define __RAW_SPIN_LOCK_UNLOCKED(lockname) \
- (raw_spinlock_t) __RAW_SPIN_LOCK_INITIALIZER(lockname)
-
-#define DEFINE_RAW_SPINLOCK(x) raw_spinlock_t x = __RAW_SPIN_LOCK_UNLOCKED(x)
-
-typedef struct spinlock {
- union {
- struct raw_spinlock rlock;
-
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define LOCK_PADSIZE (offsetof(struct raw_spinlock, dep_map))
- struct {
- u8 __padding[LOCK_PADSIZE];
- struct lockdep_map dep_map;
- };
-#endif
- };
-} spinlock_t;
-
-#define ___SPIN_LOCK_INITIALIZER(lockname) \
- { \
- .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED, \
- SPIN_DEBUG_INIT(lockname) \
- SPIN_DEP_MAP_INIT(lockname) }
-
-#define __SPIN_LOCK_INITIALIZER(lockname) \
- { { .rlock = ___SPIN_LOCK_INITIALIZER(lockname) } }
-
-#define __SPIN_LOCK_UNLOCKED(lockname) \
- (spinlock_t) __SPIN_LOCK_INITIALIZER(lockname)
-
-#define DEFINE_SPINLOCK(x) spinlock_t x = __SPIN_LOCK_UNLOCKED(x)
-
-#include <linux/rwlock_types.h>
-
#endif /* __LINUX_SPINLOCK_TYPES_H */
diff --git a/include/linux/spinlock_types_nort.h b/include/linux/spinlock_types_nort.h
new file mode 100644
index 000000000..e4549f0dd
--- /dev/null
+++ b/include/linux/spinlock_types_nort.h
@@ -0,0 +1,39 @@
+#ifndef __LINUX_SPINLOCK_TYPES_NORT_H
+#define __LINUX_SPINLOCK_TYPES_NORT_H
+
+#ifndef __LINUX_SPINLOCK_TYPES_H
+#error "Do not include directly. Include spinlock_types.h instead"
+#endif
+
+/*
+ * The non RT version maps spinlocks to raw_spinlocks
+ */
+typedef struct spinlock {
+ union {
+ struct raw_spinlock rlock;
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define LOCK_PADSIZE (offsetof(struct raw_spinlock, dep_map))
+ struct {
+ u8 __padding[LOCK_PADSIZE];
+ struct lockdep_map dep_map;
+ };
+#endif
+ };
+} spinlock_t;
+
+#define ___SPIN_LOCK_INITIALIZER(lockname) \
+{ \
+ .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED, \
+ SPIN_DEBUG_INIT(lockname) \
+ SPIN_DEP_MAP_INIT(lockname) }
+
+#define __SPIN_LOCK_INITIALIZER(lockname) \
+ { { .rlock = ___SPIN_LOCK_INITIALIZER(lockname) } }
+
+#define __SPIN_LOCK_UNLOCKED(lockname) \
+ (spinlock_t) __SPIN_LOCK_INITIALIZER(lockname)
+
+#define DEFINE_SPINLOCK(x) spinlock_t x = __SPIN_LOCK_UNLOCKED(x)
+
+#endif
diff --git a/include/linux/spinlock_types_raw.h b/include/linux/spinlock_types_raw.h
new file mode 100644
index 000000000..1d4a180e9
--- /dev/null
+++ b/include/linux/spinlock_types_raw.h
@@ -0,0 +1,65 @@
+#ifndef __LINUX_SPINLOCK_TYPES_RAW_H
+#define __LINUX_SPINLOCK_TYPES_RAW_H
+
+#include <linux/types.h>
+
+#if defined(CONFIG_SMP)
+# include <asm/spinlock_types.h>
+#else
+# include <linux/spinlock_types_up.h>
+#endif
+
+#include <linux/lockdep_types.h>
+
+typedef struct raw_spinlock {
+ arch_spinlock_t raw_lock;
+#ifdef CONFIG_DEBUG_SPINLOCK
+ unsigned int magic, owner_cpu;
+ void *owner;
+#endif
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif
+} raw_spinlock_t;
+
+#define SPINLOCK_MAGIC 0xdead4ead
+
+#define SPINLOCK_OWNER_INIT ((void *)-1L)
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define RAW_SPIN_DEP_MAP_INIT(lockname) \
+ .dep_map = { \
+ .name = #lockname, \
+ .wait_type_inner = LD_WAIT_SPIN, \
+ }
+# define SPIN_DEP_MAP_INIT(lockname) \
+ .dep_map = { \
+ .name = #lockname, \
+ .wait_type_inner = LD_WAIT_CONFIG, \
+ }
+#else
+# define RAW_SPIN_DEP_MAP_INIT(lockname)
+# define SPIN_DEP_MAP_INIT(lockname)
+#endif
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+# define SPIN_DEBUG_INIT(lockname) \
+ .magic = SPINLOCK_MAGIC, \
+ .owner_cpu = -1, \
+ .owner = SPINLOCK_OWNER_INIT,
+#else
+# define SPIN_DEBUG_INIT(lockname)
+#endif
+
+#define __RAW_SPIN_LOCK_INITIALIZER(lockname) \
+{ \
+ .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED, \
+ SPIN_DEBUG_INIT(lockname) \
+ RAW_SPIN_DEP_MAP_INIT(lockname) }
+
+#define __RAW_SPIN_LOCK_UNLOCKED(lockname) \
+ (raw_spinlock_t) __RAW_SPIN_LOCK_INITIALIZER(lockname)
+
+#define DEFINE_RAW_SPINLOCK(x) raw_spinlock_t x = __RAW_SPIN_LOCK_UNLOCKED(x)
+
+#endif
diff --git a/include/linux/spinlock_types_rt.h b/include/linux/spinlock_types_rt.h
new file mode 100644
index 000000000..446da786e
--- /dev/null
+++ b/include/linux/spinlock_types_rt.h
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef __LINUX_SPINLOCK_TYPES_RT_H
+#define __LINUX_SPINLOCK_TYPES_RT_H
+
+#ifndef __LINUX_SPINLOCK_TYPES_H
+#error "Do not include directly. Include spinlock_types.h instead"
+#endif
+
+#include <linux/cache.h>
+
+/*
+ * PREEMPT_RT: spinlocks - an RT mutex plus lock-break field:
+ */
+typedef struct spinlock {
+ struct rt_mutex lock;
+ unsigned int break_lock;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif
+} spinlock_t;
+
+#define __RT_SPIN_INITIALIZER(name) \
+ { \
+ .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(name.wait_lock), \
+ .save_state = 1, \
+ }
+/*
+.wait_list = PLIST_HEAD_INIT_RAW((name).lock.wait_list, (name).lock.wait_lock)
+*/
+
+#define __SPIN_LOCK_UNLOCKED(name) \
+ { .lock = __RT_SPIN_INITIALIZER(name.lock), \
+ SPIN_DEP_MAP_INIT(name) }
+
+#define DEFINE_SPINLOCK(name) \
+ spinlock_t name = __SPIN_LOCK_UNLOCKED(name)
+
+#endif
diff --git a/include/linux/spinlock_types_up.h b/include/linux/spinlock_types_up.h
index c09b6407a..d9b371fa1 100644
--- a/include/linux/spinlock_types_up.h
+++ b/include/linux/spinlock_types_up.h
@@ -1,7 +1,7 @@
#ifndef __LINUX_SPINLOCK_TYPES_UP_H
#define __LINUX_SPINLOCK_TYPES_UP_H
-#ifndef __LINUX_SPINLOCK_TYPES_H
+#if !defined(__LINUX_SPINLOCK_TYPES_H) && !defined(__LINUX_RT_MUTEX_H)
# error "please don't include this file directly"
#endif
diff --git a/include/linux/stop_machine.h b/include/linux/stop_machine.h
index 2959b9e52..f9f7c954b 100644
--- a/include/linux/stop_machine.h
+++ b/include/linux/stop_machine.h
@@ -25,6 +25,7 @@ typedef int (*cpu_stop_fn_t)(void *arg);
struct cpu_stop_work {
struct list_head list; /* cpu_stopper->works */
cpu_stop_fn_t fn;
+ unsigned long caller;
void *arg;
struct cpu_stop_done *done;
KABI_RESERVE(1)
@@ -38,6 +39,8 @@ void stop_machine_park(int cpu);
void stop_machine_unpark(int cpu);
void stop_machine_yield(const struct cpumask *cpumask);
+extern void print_stop_info(const char *log_lvl, struct task_struct *task);
+
#else /* CONFIG_SMP */
#include <linux/workqueue.h>
@@ -82,6 +85,8 @@ static inline bool stop_one_cpu_nowait(unsigned int cpu,
return false;
}
+static inline void print_stop_info(const char *log_lvl, struct task_struct *task) { }
+
#endif /* CONFIG_SMP */
/*
diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h
index af3ca6429..a8a76b4be 100644
--- a/include/linux/thread_info.h
+++ b/include/linux/thread_info.h
@@ -51,7 +51,17 @@ static __always_inline unsigned long read_ti_thread_flags(struct thread_info *ti
#define read_task_thread_flags(t) \
read_ti_thread_flags(task_thread_info(t))
-#define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED)
+#ifdef CONFIG_PREEMPT_LAZY
+#define tif_need_resched() (test_thread_flag(TIF_NEED_RESCHED) || \
+ test_thread_flag(TIF_NEED_RESCHED_LAZY))
+#define tif_need_resched_now() (test_thread_flag(TIF_NEED_RESCHED))
+#define tif_need_resched_lazy() test_thread_flag(TIF_NEED_RESCHED_LAZY))
+
+#else
+#define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED)
+#define tif_need_resched_now() test_thread_flag(TIF_NEED_RESCHED)
+#define tif_need_resched_lazy() 0
+#endif
#ifndef CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES
static inline int arch_within_stack_frames(const void * const stack,
diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index 9be53cc71..d52cfe995 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -67,6 +67,8 @@ struct trace_entry {
unsigned char flags;
unsigned char preempt_count;
int pid;
+ unsigned char migrate_disable;
+ unsigned char preempt_lazy_count;
};
#define TRACE_EVENT_TYPE_MAX \
@@ -152,17 +154,66 @@ static inline void tracing_generic_entry_update(struct trace_entry *entry,
unsigned short type,
unsigned int trace_ctx)
{
- struct task_struct *tsk = current;
-
entry->preempt_count = trace_ctx & 0xff;
- entry->pid = (tsk) ? tsk->pid : 0;
+ entry->migrate_disable = (trace_ctx >> 8) & 0xff;
+ entry->preempt_lazy_count = (trace_ctx >> 16) & 0xff;
+ entry->pid = current->pid;
entry->type = type;
- entry->flags = trace_ctx >> 16;
+ entry->flags = trace_ctx >> 24;
}
-unsigned int tracing_gen_ctx_flags(unsigned long irqflags);
-unsigned int tracing_gen_ctx(void);
-unsigned int tracing_gen_ctx_dec(void);
+unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status);
+
+enum trace_flag_type {
+ TRACE_FLAG_IRQS_OFF = 0x01,
+ TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
+ TRACE_FLAG_NEED_RESCHED = 0x04,
+ TRACE_FLAG_HARDIRQ = 0x08,
+ TRACE_FLAG_SOFTIRQ = 0x10,
+ TRACE_FLAG_PREEMPT_RESCHED = 0x20,
+ TRACE_FLAG_NMI = 0x40,
+ TRACE_FLAG_NEED_RESCHED_LAZY = 0x80,
+};
+
+#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
+static inline unsigned int tracing_gen_ctx_flags(unsigned long irqflags)
+{
+ unsigned int irq_status = irqs_disabled_flags(irqflags) ?
+ TRACE_FLAG_IRQS_OFF : 0;
+ return tracing_gen_ctx_irq_test(irq_status);
+}
+static inline unsigned int tracing_gen_ctx(void)
+{
+ unsigned long irqflags;
+
+ local_save_flags(irqflags);
+ return tracing_gen_ctx_flags(irqflags);
+}
+#else
+
+static inline unsigned int tracing_gen_ctx_flags(unsigned long irqflags)
+{
+ return tracing_gen_ctx_irq_test(TRACE_FLAG_IRQS_NOSUPPORT);
+}
+static inline unsigned int tracing_gen_ctx(void)
+{
+ return tracing_gen_ctx_irq_test(TRACE_FLAG_IRQS_NOSUPPORT);
+}
+#endif
+
+static inline unsigned int tracing_gen_ctx_dec(void)
+{
+ unsigned int trace_ctx;
+
+ trace_ctx = tracing_gen_ctx();
+ /*
+ * Subtract one from the preeption counter if preemption is enabled,
+ * see trace_event_buffer_reserve()for details.
+ */
+ if (IS_ENABLED(CONFIG_PREEMPTION))
+ trace_ctx--;
+ return trace_ctx;
+}
struct trace_event_file;
diff --git a/include/linux/u64_stats_sync.h b/include/linux/u64_stats_sync.h
index 7c6f81b89..f23192d55 100644
--- a/include/linux/u64_stats_sync.h
+++ b/include/linux/u64_stats_sync.h
@@ -66,7 +66,7 @@
#include <linux/seqlock.h>
struct u64_stats_sync {
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG==32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
seqcount_t seq;
#endif
};
@@ -115,7 +115,7 @@ static inline void u64_stats_inc(u64_stats_t *p)
}
#endif
-#if BITS_PER_LONG == 32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
#define u64_stats_init(syncp) \
do { \
struct u64_stats_sync *__s = (syncp); \
@@ -129,15 +129,19 @@ static inline void u64_stats_init(struct u64_stats_sync *syncp)
static inline void u64_stats_update_begin(struct u64_stats_sync *syncp)
{
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
+ if (IS_ENABLED(CONFIG_PREEMPT_RT))
+ preempt_disable();
write_seqcount_begin(&syncp->seq);
#endif
}
static inline void u64_stats_update_end(struct u64_stats_sync *syncp)
{
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
write_seqcount_end(&syncp->seq);
+ if (IS_ENABLED(CONFIG_PREEMPT_RT))
+ preempt_enable();
#endif
}
@@ -146,8 +150,11 @@ u64_stats_update_begin_irqsave(struct u64_stats_sync *syncp)
{
unsigned long flags = 0;
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
- local_irq_save(flags);
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
+ if (IS_ENABLED(CONFIG_PREEMPT_RT))
+ preempt_disable();
+ else
+ local_irq_save(flags);
write_seqcount_begin(&syncp->seq);
#endif
return flags;
@@ -157,15 +164,18 @@ static inline void
u64_stats_update_end_irqrestore(struct u64_stats_sync *syncp,
unsigned long flags)
{
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
write_seqcount_end(&syncp->seq);
- local_irq_restore(flags);
+ if (IS_ENABLED(CONFIG_PREEMPT_RT))
+ preempt_enable();
+ else
+ local_irq_restore(flags);
#endif
}
static inline unsigned int __u64_stats_fetch_begin(const struct u64_stats_sync *syncp)
{
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
return read_seqcount_begin(&syncp->seq);
#else
return 0;
@@ -174,7 +184,7 @@ static inline unsigned int __u64_stats_fetch_begin(const struct u64_stats_sync *
static inline unsigned int u64_stats_fetch_begin(const struct u64_stats_sync *syncp)
{
-#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (!defined(CONFIG_SMP) && !defined(CONFIG_PREEMPT_RT))
preempt_disable();
#endif
return __u64_stats_fetch_begin(syncp);
@@ -183,7 +193,7 @@ static inline unsigned int u64_stats_fetch_begin(const struct u64_stats_sync *sy
static inline bool __u64_stats_fetch_retry(const struct u64_stats_sync *syncp,
unsigned int start)
{
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
return read_seqcount_retry(&syncp->seq, start);
#else
return false;
@@ -193,7 +203,7 @@ static inline bool __u64_stats_fetch_retry(const struct u64_stats_sync *syncp,
static inline bool u64_stats_fetch_retry(const struct u64_stats_sync *syncp,
unsigned int start)
{
-#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (!defined(CONFIG_SMP) && !defined(CONFIG_PREEMPT_RT))
preempt_enable();
#endif
return __u64_stats_fetch_retry(syncp, start);
@@ -207,7 +217,9 @@ static inline bool u64_stats_fetch_retry(const struct u64_stats_sync *syncp,
*/
static inline unsigned int u64_stats_fetch_begin_irq(const struct u64_stats_sync *syncp)
{
-#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && defined(CONFIG_PREEMPT_RT)
+ preempt_disable();
+#elif BITS_PER_LONG == 32 && !defined(CONFIG_SMP)
local_irq_disable();
#endif
return __u64_stats_fetch_begin(syncp);
@@ -216,7 +228,9 @@ static inline unsigned int u64_stats_fetch_begin_irq(const struct u64_stats_sync
static inline bool u64_stats_fetch_retry_irq(const struct u64_stats_sync *syncp,
unsigned int start)
{
-#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && defined(CONFIG_PREEMPT_RT)
+ preempt_enable();
+#elif BITS_PER_LONG == 32 && !defined(CONFIG_SMP)
local_irq_enable();
#endif
return __u64_stats_fetch_retry(syncp, start);
diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
index 322dcbfcc..9a3a10ea3 100644
--- a/include/linux/vmstat.h
+++ b/include/linux/vmstat.h
@@ -63,7 +63,9 @@ DECLARE_PER_CPU(struct vm_event_state, vm_event_states);
*/
static inline void __count_vm_event(enum vm_event_item item)
{
+ preempt_disable_rt();
raw_cpu_inc(vm_event_states.event[item]);
+ preempt_enable_rt();
}
static inline void count_vm_event(enum vm_event_item item)
@@ -73,7 +75,9 @@ static inline void count_vm_event(enum vm_event_item item)
static inline void __count_vm_events(enum vm_event_item item, long delta)
{
+ preempt_disable_rt();
raw_cpu_add(vm_event_states.event[item], delta);
+ preempt_enable_rt();
}
static inline void count_vm_events(enum vm_event_item item, long delta)
diff --git a/include/linux/vtime.h b/include/linux/vtime.h
index 2cdeca062..041d6524d 100644
--- a/include/linux/vtime.h
+++ b/include/linux/vtime.h
@@ -83,36 +83,46 @@ static inline void vtime_init_idle(struct task_struct *tsk, int cpu) { }
#endif
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
-extern void vtime_account_irq_enter(struct task_struct *tsk);
-static inline void vtime_account_irq_exit(struct task_struct *tsk)
-{
- /* On hard|softirq exit we always account to hard|softirq cputime */
- vtime_account_kernel(tsk);
-}
+extern void vtime_account_irq(struct task_struct *tsk, unsigned int offset);
+extern void vtime_account_softirq(struct task_struct *tsk);
+extern void vtime_account_hardirq(struct task_struct *tsk);
extern void vtime_flush(struct task_struct *tsk);
#else /* !CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
-static inline void vtime_account_irq_enter(struct task_struct *tsk) { }
-static inline void vtime_account_irq_exit(struct task_struct *tsk) { }
+static inline void vtime_account_irq(struct task_struct *tsk, unsigned int offset) { }
+static inline void vtime_account_softirq(struct task_struct *tsk) { }
+static inline void vtime_account_hardirq(struct task_struct *tsk) { }
static inline void vtime_flush(struct task_struct *tsk) { }
#endif
#ifdef CONFIG_IRQ_TIME_ACCOUNTING
-extern void irqtime_account_irq(struct task_struct *tsk);
+extern void irqtime_account_irq(struct task_struct *tsk, unsigned int offset);
#else
-static inline void irqtime_account_irq(struct task_struct *tsk) { }
+static inline void irqtime_account_irq(struct task_struct *tsk, unsigned int offset) { }
#endif
-static inline void account_irq_enter_time(struct task_struct *tsk)
+static inline void account_softirq_enter(struct task_struct *tsk)
+{
+ vtime_account_irq(tsk, SOFTIRQ_OFFSET);
+ irqtime_account_irq(tsk, SOFTIRQ_OFFSET);
+}
+
+static inline void account_softirq_exit(struct task_struct *tsk)
+{
+ vtime_account_softirq(tsk);
+ irqtime_account_irq(tsk, 0);
+}
+
+static inline void account_hardirq_enter(struct task_struct *tsk)
{
- vtime_account_irq_enter(tsk);
- irqtime_account_irq(tsk);
+ vtime_account_irq(tsk, HARDIRQ_OFFSET);
+ irqtime_account_irq(tsk, HARDIRQ_OFFSET);
}
-static inline void account_irq_exit_time(struct task_struct *tsk)
+static inline void account_hardirq_exit(struct task_struct *tsk)
{
- vtime_account_irq_exit(tsk);
- irqtime_account_irq(tsk);
+ vtime_account_hardirq(tsk);
+ irqtime_account_irq(tsk, 0);
}
#endif /* _LINUX_KERNEL_VTIME_H */
diff --git a/include/linux/wait.h b/include/linux/wait.h
index ba5ac7f29..c1b63739e 100644
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -10,6 +10,7 @@
#include <asm/current.h>
#include <uapi/linux/wait.h>
+#include <linux/atomic.h>
typedef struct wait_queue_entry wait_queue_entry_t;
diff --git a/include/linux/ww_mutex.h b/include/linux/ww_mutex.h
index 6ecf2a022..3145de598 100644
--- a/include/linux/ww_mutex.h
+++ b/include/linux/ww_mutex.h
@@ -28,6 +28,14 @@ struct ww_class {
unsigned int is_wait_die;
};
+struct ww_mutex {
+ struct mutex base;
+ struct ww_acquire_ctx *ctx;
+#ifdef CONFIG_DEBUG_MUTEXES
+ struct ww_class *ww_class;
+#endif
+};
+
struct ww_acquire_ctx {
struct task_struct *task;
unsigned long stamp;
diff --git a/include/net/gen_stats.h b/include/net/gen_stats.h
index 1424e02ce..163f8415e 100644
--- a/include/net/gen_stats.h
+++ b/include/net/gen_stats.h
@@ -6,6 +6,7 @@
#include <linux/socket.h>
#include <linux/rtnetlink.h>
#include <linux/pkt_sched.h>
+#include <net/net_seq_lock.h>
/* Note: this used to be in include/uapi/linux/gen_stats.h */
struct gnet_stats_basic_packed {
@@ -42,15 +43,15 @@ int gnet_stats_start_copy_compat(struct sk_buff *skb, int type,
spinlock_t *lock, struct gnet_dump *d,
int padattr);
-int gnet_stats_copy_basic(const seqcount_t *running,
+int gnet_stats_copy_basic(net_seqlock_t *running,
struct gnet_dump *d,
struct gnet_stats_basic_cpu __percpu *cpu,
struct gnet_stats_basic_packed *b);
-void __gnet_stats_copy_basic(const seqcount_t *running,
+void __gnet_stats_copy_basic(net_seqlock_t *running,
struct gnet_stats_basic_packed *bstats,
struct gnet_stats_basic_cpu __percpu *cpu,
struct gnet_stats_basic_packed *b);
-int gnet_stats_copy_basic_hw(const seqcount_t *running,
+int gnet_stats_copy_basic_hw(net_seqlock_t *running,
struct gnet_dump *d,
struct gnet_stats_basic_cpu __percpu *cpu,
struct gnet_stats_basic_packed *b);
@@ -70,13 +71,13 @@ int gen_new_estimator(struct gnet_stats_basic_packed *bstats,
struct gnet_stats_basic_cpu __percpu *cpu_bstats,
struct net_rate_estimator __rcu **rate_est,
spinlock_t *lock,
- seqcount_t *running, struct nlattr *opt);
+ net_seqlock_t *running, struct nlattr *opt);
void gen_kill_estimator(struct net_rate_estimator __rcu **ptr);
int gen_replace_estimator(struct gnet_stats_basic_packed *bstats,
struct gnet_stats_basic_cpu __percpu *cpu_bstats,
struct net_rate_estimator __rcu **ptr,
spinlock_t *lock,
- seqcount_t *running, struct nlattr *opt);
+ net_seqlock_t *running, struct nlattr *opt);
bool gen_estimator_active(struct net_rate_estimator __rcu **ptr);
bool gen_estimator_read(struct net_rate_estimator __rcu **ptr,
struct gnet_stats_rate_est64 *sample);
diff --git a/include/net/net_seq_lock.h b/include/net/net_seq_lock.h
new file mode 100644
index 000000000..67710bace
--- /dev/null
+++ b/include/net/net_seq_lock.h
@@ -0,0 +1,15 @@
+#ifndef __NET_NET_SEQ_LOCK_H__
+#define __NET_NET_SEQ_LOCK_H__
+
+#ifdef CONFIG_PREEMPT_RT
+# define net_seqlock_t seqlock_t
+# define net_seq_begin(__r) read_seqbegin(__r)
+# define net_seq_retry(__r, __s) read_seqretry(__r, __s)
+
+#else
+# define net_seqlock_t seqcount_t
+# define net_seq_begin(__r) read_seqcount_begin(__r)
+# define net_seq_retry(__r, __s) read_seqcount_retry(__r, __s)
+#endif
+
+#endif
diff --git a/include/net/netns/xfrm.h b/include/net/netns/xfrm.h
index 9144e0f09..464d14b2a 100644
--- a/include/net/netns/xfrm.h
+++ b/include/net/netns/xfrm.h
@@ -74,7 +74,7 @@ struct netns_xfrm {
struct dst_ops xfrm6_dst_ops;
#endif
spinlock_t xfrm_state_lock;
- seqcount_t xfrm_state_hash_generation;
+ seqcount_spinlock_t xfrm_state_hash_generation;
seqcount_spinlock_t xfrm_policy_hash_generation;
spinlock_t xfrm_policy_lock;
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index efacdfee3..02871f48c 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -10,6 +10,7 @@
#include <linux/percpu.h>
#include <linux/dynamic_queue_limits.h>
#include <linux/list.h>
+#include <net/net_seq_lock.h>
#include <linux/refcount.h>
#include <linux/workqueue.h>
#include <linux/mutex.h>
@@ -102,7 +103,7 @@ struct Qdisc {
struct sk_buff_head gso_skb ____cacheline_aligned_in_smp;
struct qdisc_skb_head q;
struct gnet_stats_basic_packed bstats;
- seqcount_t running;
+ net_seqlock_t running;
struct gnet_stats_queue qstats;
unsigned long state;
struct Qdisc *next_sched;
@@ -146,7 +147,11 @@ static inline bool qdisc_is_running(struct Qdisc *qdisc)
{
if (qdisc->flags & TCQ_F_NOLOCK)
return spin_is_locked(&qdisc->seqlock);
+#ifdef CONFIG_PREEMPT_RT
+ return spin_is_locked(&qdisc->running.lock) ? true : false;
+#else
return (raw_read_seqcount(&qdisc->running) & 1) ? true : false;
+#endif
}
static inline bool qdisc_is_percpu_stats(const struct Qdisc *q)
@@ -187,17 +192,35 @@ nolock_empty:
} else if (qdisc_is_running(qdisc)) {
return false;
}
+#ifdef CONFIG_PREEMPT_RT
+ if (spin_trylock(&qdisc->running.lock)) {
+ seqcount_t *s = &qdisc->running.seqcount.seqcount;
+ /*
+ * Variant of write_seqcount_t_begin() telling lockdep that a
+ * trylock was attempted.
+ */
+ raw_write_seqcount_begin(s);
+ seqcount_acquire(&s->dep_map, 0, 1, _RET_IP_);
+ return true;
+ }
+ return false;
+#else
/* Variant of write_seqcount_begin() telling lockdep a trylock
* was attempted.
*/
raw_write_seqcount_begin(&qdisc->running);
seqcount_acquire(&qdisc->running.dep_map, 0, 1, _RET_IP_);
return true;
+#endif
}
static inline void qdisc_run_end(struct Qdisc *qdisc)
{
+#ifdef CONFIG_PREEMPT_RT
+ write_sequnlock(&qdisc->running);
+#else
write_seqcount_end(&qdisc->running);
+#endif
if (qdisc->flags & TCQ_F_NOLOCK) {
spin_unlock(&qdisc->seqlock);
@@ -591,7 +614,7 @@ static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
return qdisc_lock(root);
}
-static inline seqcount_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc)
+static inline net_seqlock_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc)
{
struct Qdisc *root = qdisc_root_sleeping(qdisc);
diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index eb5ec1fb6..122d96db9 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -732,6 +732,18 @@ DEFINE_EVENT(psi_memstall_template, psi_memstall_leave,
TP_ARGS(function)
);
+DECLARE_TRACE(sched_migrate_disable_tp,
+ TP_PROTO(struct task_struct *p),
+ TP_ARGS(p));
+
+DECLARE_TRACE(sched_migrate_enable_tp,
+ TP_PROTO(struct task_struct *p),
+ TP_ARGS(p));
+
+DECLARE_TRACE(sched_migrate_pull_tp,
+ TP_PROTO(struct task_struct *p),
+ TP_ARGS(p));
+
#endif /* _TRACE_SCHED_H */
/* This part must be outside protection */
diff --git a/init/Kconfig b/init/Kconfig
index be284bca4..cbe7ad86b 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -899,7 +899,7 @@ config NUMA_BALANCING
bool "Memory placement aware NUMA scheduler"
depends on ARCH_SUPPORTS_NUMA_BALANCING
depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY
- depends on SMP && NUMA && MIGRATION
+ depends on SMP && NUMA && MIGRATION && !PREEMPT_RT
help
This option adds support for automatic NUMA aware memory/task placement.
The mechanism is quite primitive and is based on migrating memory when
@@ -1066,6 +1066,7 @@ config CFS_BANDWIDTH
config RT_GROUP_SCHED
bool "Group scheduling for SCHED_RR/FIFO"
depends on CGROUP_SCHED
+ depends on !PREEMPT_RT
default n
help
This feature lets you explicitly allocate real CPU bandwidth
@@ -2108,6 +2109,7 @@ choice
config SLAB
bool "SLAB"
+ depends on !PREEMPT_RT
select HAVE_HARDENED_USERCOPY_ALLOCATOR
help
The regular slab allocator that is established and known to work
@@ -2128,6 +2130,7 @@ config SLUB
config SLOB
depends on EXPERT
bool "SLOB (Simple Allocator)"
+ depends on !PREEMPT_RT
help
SLOB replaces the stock allocator with a drastically simpler
allocator. SLOB is generally more space efficient but
@@ -2194,7 +2197,7 @@ config SHUFFLE_PAGE_ALLOCATOR
config SLUB_CPU_PARTIAL
default y
- depends on SLUB && SMP
+ depends on SLUB && SMP && !PREEMPT_RT
bool "SLUB per cpu partial cache"
help
Per cpu partial caches accelerate objects allocation and freeing
diff --git a/kernel/Kconfig.locks b/kernel/Kconfig.locks
index 3de8fd118..4198f0273 100644
--- a/kernel/Kconfig.locks
+++ b/kernel/Kconfig.locks
@@ -251,7 +251,7 @@ config ARCH_USE_QUEUED_RWLOCKS
config QUEUED_RWLOCKS
def_bool y if ARCH_USE_QUEUED_RWLOCKS
- depends on SMP
+ depends on SMP && !PREEMPT_RT
config ARCH_HAS_MMIOWB
bool
diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt
index e62a62303..b95f8784c 100644
--- a/kernel/Kconfig.preempt
+++ b/kernel/Kconfig.preempt
@@ -1,5 +1,11 @@
# SPDX-License-Identifier: GPL-2.0-only
+config HAVE_PREEMPT_LAZY
+ bool
+
+config PREEMPT_LAZY
+ def_bool y if HAVE_PREEMPT_LAZY && PREEMPT_RT
+
choice
prompt "Preemption Model"
default PREEMPT_NONE
@@ -60,6 +66,7 @@ config PREEMPT_RT
bool "Fully Preemptible Kernel (Real-Time)"
depends on EXPERT && ARCH_SUPPORTS_RT
select PREEMPTION
+ select RT_MUTEXES
help
This option turns the kernel into a real-time kernel by replacing
various locking primitives (spinlocks, rwlocks, etc.) with
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 7ecff06d2..a9fe99b9f 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -381,7 +381,7 @@ void cpuset_unlock(void)
mutex_unlock(&cpuset_mutex);
}
-static DEFINE_SPINLOCK(callback_lock);
+static DEFINE_RAW_SPINLOCK(callback_lock);
static struct workqueue_struct *cpuset_migrate_mm_wq;
@@ -760,9 +760,9 @@ static int update_prefer_cpumask(struct cpuset *cs, struct cpuset *trialcs,
if (!cpumask_empty(trialcs->prefer_cpus))
dynamic_affinity_enable();
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
cpumask_copy(cs->prefer_cpus, trialcs->prefer_cpus);
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
return 0;
}
@@ -1432,7 +1432,7 @@ static int update_parent_subparts_cpumask(struct cpuset *cpuset, int cmd,
* Newly added CPUs will be removed from effective_cpus and
* newly deleted ones will be added back to effective_cpus.
*/
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
if (adding) {
cpumask_or(parent->subparts_cpus,
parent->subparts_cpus, tmp->addmask);
@@ -1454,7 +1454,7 @@ static int update_parent_subparts_cpumask(struct cpuset *cpuset, int cmd,
if (cpuset->partition_root_state != new_prs)
cpuset->partition_root_state = new_prs;
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
return cmd == partcmd_update;
}
@@ -1557,7 +1557,7 @@ static void update_cpumasks_hier(struct cpuset *cs, struct tmpmasks *tmp)
continue;
rcu_read_unlock();
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
cpumask_copy(cp->effective_cpus, tmp->new_cpus);
if (cp->nr_subparts_cpus && (new_prs != PRS_ENABLED)) {
@@ -1591,7 +1591,7 @@ static void update_cpumasks_hier(struct cpuset *cs, struct tmpmasks *tmp)
if (new_prs != cp->partition_root_state)
cp->partition_root_state = new_prs;
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
WARN_ON(!is_in_v2_mode() &&
!cpumask_equal(cp->cpus_allowed, cp->effective_cpus));
@@ -1719,7 +1719,7 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
return -EINVAL;
}
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
cpumask_copy(cs->cpus_allowed, trialcs->cpus_allowed);
/*
@@ -1729,7 +1729,7 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
cpumask_and(cs->subparts_cpus, cs->subparts_cpus, cs->cpus_allowed);
cs->nr_subparts_cpus = cpumask_weight(cs->subparts_cpus);
}
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
update_cpumasks_hier(cs, &tmp);
@@ -1923,9 +1923,9 @@ static void update_nodemasks_hier(struct cpuset *cs, nodemask_t *new_mems)
continue;
rcu_read_unlock();
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
cp->effective_mems = *new_mems;
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
WARN_ON(!is_in_v2_mode() &&
!nodes_equal(cp->mems_allowed, cp->effective_mems));
@@ -1993,9 +1993,9 @@ static int update_nodemask(struct cpuset *cs, struct cpuset *trialcs,
if (retval < 0)
goto done;
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
cs->mems_allowed = trialcs->mems_allowed;
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
/* use trialcs->mems_allowed as a temp variable */
update_nodemasks_hier(cs, &trialcs->mems_allowed);
@@ -2086,9 +2086,9 @@ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
spread_flag_changed = ((is_spread_slab(cs) != is_spread_slab(trialcs))
|| (is_spread_page(cs) != is_spread_page(trialcs)));
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
cs->flags = trialcs->flags;
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
if (!cpumask_empty(trialcs->cpus_allowed) && balance_flag_changed)
rebuild_sched_domains_locked();
@@ -2174,9 +2174,9 @@ static int update_prstate(struct cpuset *cs, int new_prs)
rebuild_sched_domains_locked();
out:
if (!err) {
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
cs->partition_root_state = new_prs;
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
}
free_cpumasks(NULL, &tmpmask);
@@ -2658,7 +2658,7 @@ static int cpuset_common_seq_show(struct seq_file *sf, void *v)
cpuset_filetype_t type = seq_cft(sf)->private;
int ret = 0;
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
switch (type) {
case FILE_CPULIST:
@@ -2685,7 +2685,7 @@ static int cpuset_common_seq_show(struct seq_file *sf, void *v)
ret = -EINVAL;
}
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
return ret;
}
@@ -3006,14 +3006,14 @@ static int cpuset_css_online(struct cgroup_subsys_state *css)
cpuset_inc();
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
if (is_in_v2_mode()) {
cpumask_copy(cs->effective_cpus, parent->effective_cpus);
cs->effective_mems = parent->effective_mems;
cs->use_parent_ecpus = true;
parent->child_ecpus_count++;
}
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
if (!test_bit(CGRP_CPUSET_CLONE_CHILDREN, &css->cgroup->flags))
goto out_unlock;
@@ -3040,7 +3040,7 @@ static int cpuset_css_online(struct cgroup_subsys_state *css)
}
rcu_read_unlock();
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
cs->mems_allowed = parent->mems_allowed;
cs->effective_mems = parent->mems_allowed;
cpumask_copy(cs->cpus_allowed, parent->cpus_allowed);
@@ -3048,7 +3048,7 @@ static int cpuset_css_online(struct cgroup_subsys_state *css)
#ifdef CONFIG_QOS_SCHED_DYNAMIC_AFFINITY
cpumask_copy(cs->prefer_cpus, parent->prefer_cpus);
#endif
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
out_unlock:
mutex_unlock(&cpuset_mutex);
put_online_cpus();
@@ -3104,7 +3104,7 @@ static void cpuset_css_free(struct cgroup_subsys_state *css)
static void cpuset_bind(struct cgroup_subsys_state *root_css)
{
mutex_lock(&cpuset_mutex);
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
if (is_in_v2_mode()) {
cpumask_copy(top_cpuset.cpus_allowed, cpu_possible_mask);
@@ -3115,7 +3115,7 @@ static void cpuset_bind(struct cgroup_subsys_state *root_css)
top_cpuset.mems_allowed = top_cpuset.effective_mems;
}
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
mutex_unlock(&cpuset_mutex);
}
@@ -3225,12 +3225,12 @@ hotplug_update_tasks_legacy(struct cpuset *cs,
#endif
bool is_empty;
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
cpumask_copy(cs->cpus_allowed, new_cpus);
cpumask_copy(cs->effective_cpus, new_cpus);
cs->mems_allowed = *new_mems;
cs->effective_mems = *new_mems;
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
/*
* Don't call update_tasks_cpumask() if the cpuset becomes empty,
@@ -3274,10 +3274,10 @@ hotplug_update_tasks(struct cpuset *cs,
if (nodes_empty(*new_mems))
*new_mems = parent_cs(cs)->effective_mems;
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
cpumask_copy(cs->effective_cpus, new_cpus);
cs->effective_mems = *new_mems;
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
if (cpus_updated)
update_tasks_cpumask(cs);
@@ -3344,10 +3344,10 @@ retry:
if (is_partition_root(cs) && (cpumask_empty(&new_cpus) ||
(parent->partition_root_state == PRS_ERROR))) {
if (cs->nr_subparts_cpus) {
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
cs->nr_subparts_cpus = 0;
cpumask_clear(cs->subparts_cpus);
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
compute_effective_cpumask(&new_cpus, cs, parent);
}
@@ -3361,9 +3361,9 @@ retry:
cpumask_empty(&new_cpus)) {
update_parent_subparts_cpumask(cs, partcmd_disable,
NULL, tmp);
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
cs->partition_root_state = PRS_ERROR;
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
}
cpuset_force_rebuild();
}
@@ -3443,7 +3443,7 @@ static void cpuset_hotplug_workfn(struct work_struct *work)
/* synchronize cpus_allowed to cpu_active_mask */
if (cpus_updated) {
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
if (!on_dfl)
cpumask_copy(top_cpuset.cpus_allowed, &new_cpus);
/*
@@ -3463,17 +3463,17 @@ static void cpuset_hotplug_workfn(struct work_struct *work)
}
}
cpumask_copy(top_cpuset.effective_cpus, &new_cpus);
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
/* we don't mess with cpumasks of tasks in top_cpuset */
}
/* synchronize mems_allowed to N_MEMORY */
if (mems_updated) {
- spin_lock_irq(&callback_lock);
+ raw_spin_lock_irq(&callback_lock);
if (!on_dfl)
top_cpuset.mems_allowed = new_mems;
top_cpuset.effective_mems = new_mems;
- spin_unlock_irq(&callback_lock);
+ raw_spin_unlock_irq(&callback_lock);
update_tasks_nodemask(&top_cpuset);
}
@@ -3577,11 +3577,11 @@ void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask)
{
unsigned long flags;
- spin_lock_irqsave(&callback_lock, flags);
+ raw_spin_lock_irqsave(&callback_lock, flags);
rcu_read_lock();
guarantee_online_cpus(task_cs(tsk), pmask);
rcu_read_unlock();
- spin_unlock_irqrestore(&callback_lock, flags);
+ raw_spin_unlock_irqrestore(&callback_lock, flags);
}
/**
@@ -3642,11 +3642,11 @@ nodemask_t cpuset_mems_allowed(struct task_struct *tsk)
nodemask_t mask;
unsigned long flags;
- spin_lock_irqsave(&callback_lock, flags);
+ raw_spin_lock_irqsave(&callback_lock, flags);
rcu_read_lock();
guarantee_online_mems(task_cs(tsk), &mask);
rcu_read_unlock();
- spin_unlock_irqrestore(&callback_lock, flags);
+ raw_spin_unlock_irqrestore(&callback_lock, flags);
return mask;
}
@@ -3738,14 +3738,14 @@ bool __cpuset_node_allowed(int node, gfp_t gfp_mask)
return true;
/* Not hardwall and node outside mems_allowed: scan up cpusets */
- spin_lock_irqsave(&callback_lock, flags);
+ raw_spin_lock_irqsave(&callback_lock, flags);
rcu_read_lock();
cs = nearest_hardwall_ancestor(task_cs(current));
allowed = node_isset(node, cs->mems_allowed);
rcu_read_unlock();
- spin_unlock_irqrestore(&callback_lock, flags);
+ raw_spin_unlock_irqrestore(&callback_lock, flags);
return allowed;
}
diff --git a/kernel/cgroup/rstat.c b/kernel/cgroup/rstat.c
index d2ae14d0b..7b3bea56d 100644
--- a/kernel/cgroup/rstat.c
+++ b/kernel/cgroup/rstat.c
@@ -156,8 +156,9 @@ static void cgroup_rstat_flush_locked(struct cgroup *cgrp, bool may_sleep)
raw_spinlock_t *cpu_lock = per_cpu_ptr(&cgroup_rstat_cpu_lock,
cpu);
struct cgroup *pos = NULL;
+ unsigned long flags;
- raw_spin_lock(cpu_lock);
+ raw_spin_lock_irqsave(cpu_lock, flags);
while ((pos = cgroup_rstat_cpu_pop_updated(pos, cgrp, cpu))) {
struct cgroup_subsys_state *css;
@@ -169,7 +170,7 @@ static void cgroup_rstat_flush_locked(struct cgroup *cgrp, bool may_sleep)
css->ss->css_rstat_flush(css, cpu);
rcu_read_unlock();
}
- raw_spin_unlock(cpu_lock);
+ raw_spin_unlock_irqrestore(cpu_lock, flags);
/* if @may_sleep, play nice and yield if necessary */
if (may_sleep && (need_resched() ||
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 137baebde..a3190708d 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -1731,7 +1731,7 @@ static struct cpuhp_step cpuhp_hp_states[] = {
.name = "ap:online",
},
/*
- * Handled on controll processor until the plugged processor manages
+ * Handled on control processor until the plugged processor manages
* this itself.
*/
[CPUHP_TEARDOWN_CPU] = {
@@ -1740,6 +1740,13 @@ static struct cpuhp_step cpuhp_hp_states[] = {
.teardown.single = takedown_cpu,
.cant_stop = true,
},
+
+ [CPUHP_AP_SCHED_WAIT_EMPTY] = {
+ .name = "sched:waitempty",
+ .startup.single = NULL,
+ .teardown.single = sched_cpu_wait_empty,
+ },
+
/* Handle smpboot threads park/unpark */
[CPUHP_AP_SMPBOOT_THREADS] = {
.name = "smpboot/threads:online",
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index c27b3dfa1..b97d05072 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -2155,7 +2155,7 @@ static int kdb_dmesg(int argc, const char **argv)
int adjust = 0;
int n = 0;
int skip = 0;
- struct kmsg_dumper dumper = { .active = 1 };
+ struct kmsg_dumper_iter iter = { .active = 1 };
size_t len;
char buf[201];
@@ -2180,8 +2180,8 @@ static int kdb_dmesg(int argc, const char **argv)
kdb_set(2, setargs);
}
- kmsg_dump_rewind_nolock(&dumper);
- while (kmsg_dump_get_line_nolock(&dumper, 1, NULL, 0, NULL))
+ kmsg_dump_rewind(&iter);
+ while (kmsg_dump_get_line(&iter, 1, NULL, 0, NULL))
n++;
if (lines < 0) {
@@ -2213,8 +2213,8 @@ static int kdb_dmesg(int argc, const char **argv)
if (skip >= n || skip < 0)
return 0;
- kmsg_dump_rewind_nolock(&dumper);
- while (kmsg_dump_get_line_nolock(&dumper, 1, buf, sizeof(buf), &len)) {
+ kmsg_dump_rewind(&iter);
+ while (kmsg_dump_get_line(&iter, 1, buf, sizeof(buf), &len)) {
if (skip) {
skip--;
continue;
diff --git a/kernel/entry/common.c b/kernel/entry/common.c
index b3690d7ea..23eb61839 100644
--- a/kernel/entry/common.c
+++ b/kernel/entry/common.c
@@ -2,6 +2,7 @@
#include <linux/context_tracking.h>
#include <linux/entry-common.h>
+#include <linux/highmem.h>
#include <linux/livepatch.h>
#include <linux/audit.h>
@@ -156,9 +157,17 @@ static unsigned long exit_to_user_mode_loop(struct pt_regs *regs,
local_irq_enable_exit_to_user(ti_work);
- if (ti_work & _TIF_NEED_RESCHED)
+ if (ti_work & _TIF_NEED_RESCHED_MASK)
schedule();
+#ifdef ARCH_RT_DELAYS_SIGNAL_SEND
+ if (unlikely(current->forced_info.si_signo)) {
+ struct task_struct *t = current;
+ force_sig_info(&t->forced_info);
+ t->forced_info.si_signo = 0;
+ }
+#endif
+
if (ti_work & _TIF_UPROBE)
uprobe_notify_resume(regs);
@@ -210,6 +219,7 @@ static void exit_to_user_mode_prepare(struct pt_regs *regs)
/* Ensure that the address limit is intact and no locks are held */
addr_limit_user_check();
+ kmap_assert_nomap();
lockdep_assert_irqs_disabled();
lockdep_sys_exit();
}
@@ -369,7 +379,7 @@ void irqentry_exit_cond_resched(void)
rcu_irq_exit_check_preempt();
if (IS_ENABLED(CONFIG_DEBUG_ENTRY))
WARN_ON_ONCE(!on_thread_stack());
- if (need_resched())
+ if (should_resched(0))
preempt_schedule_irq();
}
}
diff --git a/kernel/exit.c b/kernel/exit.c
index 26a81ea63..c15ca5450 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -153,7 +153,7 @@ static void __exit_signal(struct task_struct *tsk)
* Do this under ->siglock, we can race with another thread
* doing sigqueue_free() if we have SIGQUEUE_PREALLOC signals.
*/
- flush_sigqueue(&tsk->pending);
+ flush_task_sigqueue(tsk);
tsk->sighand = NULL;
spin_unlock(&sighand->siglock);
diff --git a/kernel/fork.c b/kernel/fork.c
index 9b1ea79de..009c07729 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -42,6 +42,7 @@
#include <linux/mmu_notifier.h>
#include <linux/fs.h>
#include <linux/mm.h>
+#include <linux/kprobes.h>
#include <linux/vmacache.h>
#include <linux/nsproxy.h>
#include <linux/capability.h>
@@ -294,7 +295,7 @@ static inline void free_thread_stack(struct task_struct *tsk)
return;
}
- vfree_atomic(tsk->stack);
+ vfree(tsk->stack);
return;
}
#endif
@@ -707,6 +708,19 @@ void __mmdrop(struct mm_struct *mm)
}
EXPORT_SYMBOL_GPL(__mmdrop);
+#ifdef CONFIG_PREEMPT_RT
+/*
+ * RCU callback for delayed mm drop. Not strictly rcu, but we don't
+ * want another facility to make this work.
+ */
+void __mmdrop_delayed(struct rcu_head *rhp)
+{
+ struct mm_struct *mm = container_of(rhp, struct mm_struct, delayed_drop);
+
+ __mmdrop(mm);
+}
+#endif
+
static void mmdrop_async_fn(struct work_struct *work)
{
struct mm_struct *mm;
@@ -748,6 +762,15 @@ void __put_task_struct(struct task_struct *tsk)
WARN_ON(refcount_read(&tsk->usage));
WARN_ON(tsk == current);
+ /*
+ * Remove function-return probe instances associated with this
+ * task and put them back on the free list.
+ */
+ kprobe_flush_task(tsk);
+
+ /* Task is done with its stack. */
+ put_task_stack(tsk);
+
io_uring_free(tsk);
cgroup_free(tsk);
task_numa_free(tsk, true);
@@ -986,11 +1009,13 @@ static struct task_struct *dup_task_struct(struct task_struct *orig, int node)
tsk->task_frag.page = NULL;
tsk->wake_q.next = NULL;
tsk->pf_io_worker = NULL;
+ tsk->wake_q_sleeper.next = NULL;
account_kernel_stack(tsk, 1);
kcov_task_init(tsk);
+ kmap_local_fork(tsk);
#ifdef CONFIG_FAULT_INJECTION
tsk->fail_nth = 0;
#endif
@@ -2139,6 +2164,7 @@ static __latent_entropy struct task_struct *copy_process(
spin_lock_init(&p->alloc_lock);
init_sigpending(&p->pending);
+ p->sigqueue_cache = NULL;
p->utime = p->stime = p->gtime = 0;
#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
diff --git a/kernel/futex/core.c b/kernel/futex/core.c
index cde0ca876..909dcd708 100644
--- a/kernel/futex/core.c
+++ b/kernel/futex/core.c
@@ -1508,6 +1508,7 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_pi_state *pi_
struct task_struct *new_owner;
bool postunlock = false;
DEFINE_WAKE_Q(wake_q);
+ DEFINE_WAKE_Q(wake_sleeper_q);
int ret = 0;
new_owner = rt_mutex_next_owner(&pi_state->pi_mutex);
@@ -1557,14 +1558,15 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_pi_state *pi_
* not fail.
*/
pi_state_update_owner(pi_state, new_owner);
- postunlock = __rt_mutex_futex_unlock(&pi_state->pi_mutex, &wake_q);
+ postunlock = __rt_mutex_futex_unlock(&pi_state->pi_mutex, &wake_q,
+ &wake_sleeper_q);
}
out_unlock:
raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
if (postunlock)
- rt_mutex_postunlock(&wake_q);
+ rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
return ret;
}
@@ -2165,6 +2167,16 @@ retry_private:
*/
requeue_pi_wake_futex(this, &key2, hb2);
continue;
+ } else if (ret == -EAGAIN) {
+ /*
+ * Waiter was woken by timeout or
+ * signal and has set pi_blocked_on to
+ * PI_WAKEUP_INPROGRESS before we
+ * tried to enqueue it on the rtmutex.
+ */
+ this->pi_state = NULL;
+ put_pi_state(pi_state);
+ continue;
} else if (ret) {
/*
* rt_mutex_start_proxy_lock() detected a
@@ -2857,7 +2869,7 @@ retry_private:
goto no_block;
}
- rt_mutex_init_waiter(&rt_waiter);
+ rt_mutex_init_waiter(&rt_waiter, false);
/*
* On PREEMPT_RT_FULL, when hb->lock becomes an rt_mutex, we must not
@@ -3182,7 +3194,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
{
struct hrtimer_sleeper timeout, *to;
struct rt_mutex_waiter rt_waiter;
- struct futex_hash_bucket *hb;
+ struct futex_hash_bucket *hb, *hb2;
union futex_key key2 = FUTEX_KEY_INIT;
struct futex_q q = futex_q_init;
int res, ret;
@@ -3203,7 +3215,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
* The waiter is allocated on our stack, manipulated by the requeue
* code while we sleep on uaddr.
*/
- rt_mutex_init_waiter(&rt_waiter);
+ rt_mutex_init_waiter(&rt_waiter, false);
ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, FUTEX_WRITE);
if (unlikely(ret != 0))
@@ -3234,20 +3246,55 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
/* Queue the futex_q, drop the hb lock, wait for wakeup. */
futex_wait_queue_me(hb, &q, to);
- spin_lock(&hb->lock);
- ret = handle_early_requeue_pi_wakeup(hb, &q, &key2, to);
- spin_unlock(&hb->lock);
- if (ret)
- goto out;
+ /*
+ * On RT we must avoid races with requeue and trying to block
+ * on two mutexes (hb->lock and uaddr2's rtmutex) by
+ * serializing access to pi_blocked_on with pi_lock.
+ */
+ raw_spin_lock_irq(&current->pi_lock);
+ if (current->pi_blocked_on) {
+ /*
+ * We have been requeued or are in the process of
+ * being requeued.
+ */
+ raw_spin_unlock_irq(&current->pi_lock);
+ } else {
+ /*
+ * Setting pi_blocked_on to PI_WAKEUP_INPROGRESS
+ * prevents a concurrent requeue from moving us to the
+ * uaddr2 rtmutex. After that we can safely acquire
+ * (and possibly block on) hb->lock.
+ */
+ current->pi_blocked_on = PI_WAKEUP_INPROGRESS;
+ raw_spin_unlock_irq(&current->pi_lock);
+
+ spin_lock(&hb->lock);
+
+ /*
+ * Clean up pi_blocked_on. We might leak it otherwise
+ * when we succeeded with the hb->lock in the fast
+ * path.
+ */
+ raw_spin_lock_irq(&current->pi_lock);
+ current->pi_blocked_on = NULL;
+ raw_spin_unlock_irq(&current->pi_lock);
+
+ ret = handle_early_requeue_pi_wakeup(hb, &q, &key2, to);
+ spin_unlock(&hb->lock);
+ if (ret)
+ goto out;
+ }
/*
- * In order for us to be here, we know our q.key == key2, and since
- * we took the hb->lock above, we also know that futex_requeue() has
- * completed and we no longer have to concern ourselves with a wakeup
- * race with the atomic proxy lock acquisition by the requeue code. The
- * futex_requeue dropped our key1 reference and incremented our key2
- * reference count.
+ * In order to be here, we have either been requeued, are in
+ * the process of being requeued, or requeue successfully
+ * acquired uaddr2 on our behalf. If pi_blocked_on was
+ * non-null above, we may be racing with a requeue. Do not
+ * rely on q->lock_ptr to be hb2->lock until after blocking on
+ * hb->lock or hb2->lock. The futex_requeue dropped our key1
+ * reference and incremented our key2 reference count.
*/
+ hb2 = hash_futex(&key2);
/* Check if the requeue code acquired the second futex for us. */
if (!q.rt_waiter) {
@@ -3256,14 +3303,15 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
* did a lock-steal - fix up the PI-state in that case.
*/
if (q.pi_state && (q.pi_state->owner != current)) {
- spin_lock(q.lock_ptr);
+ spin_lock(&hb2->lock);
+ BUG_ON(&hb2->lock != q.lock_ptr);
ret = fixup_pi_state_owner(uaddr2, &q, current);
/*
* Drop the reference to the pi state which
* the requeue_pi() code acquired for us.
*/
put_pi_state(q.pi_state);
- spin_unlock(q.lock_ptr);
+ spin_unlock(&hb2->lock);
/*
* Adjust the return value. It's either -EFAULT or
* success (1) but the caller expects 0 for success.
@@ -3282,7 +3330,8 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
pi_mutex = &q.pi_state->pi_mutex;
ret = rt_mutex_wait_proxy_lock(pi_mutex, to, &rt_waiter);
- spin_lock(q.lock_ptr);
+ spin_lock(&hb2->lock);
+ BUG_ON(&hb2->lock != q.lock_ptr);
if (ret && !rt_mutex_cleanup_proxy_lock(pi_mutex, &rt_waiter))
ret = 0;
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 8806444a6..acbce92f9 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -193,9 +193,17 @@ irqreturn_t handle_irq_event_percpu(struct irq_desc *desc)
irqreturn_t retval;
unsigned int flags = 0;
+ struct pt_regs *regs = get_irq_regs();
+ u64 ip = regs ? instruction_pointer(regs) : 0;
+
retval = __handle_irq_event_percpu(desc, &flags);
+#ifdef CONFIG_PREEMPT_RT
+ desc->random_ip = ip;
+#else
add_interrupt_randomness(desc->irq_data.irq);
+#endif
+
if (!noirqdebug)
note_interrupt(desc, retval);
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 227787723..c7bf98810 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -1302,6 +1302,8 @@ static int irq_thread(void *data)
irq_thread_set_ready(desc, action);
+ sched_set_fifo(current);
+
if (force_irqthreads && test_bit(IRQTF_FORCED_THREAD,
&action->thread_flags))
handler_fn = irq_forced_thread_fn;
@@ -1322,6 +1324,16 @@ static int irq_thread(void *data)
if (action_ret == IRQ_WAKE_THREAD)
irq_wake_secondary(desc, action);
+ if (IS_ENABLED(CONFIG_PREEMPT_RT)) {
+ migrate_disable();
+ // add_interrupt_randomness(action->irq, 0,
+ // desc->random_ip ^ (unsigned long) action);
+
+ add_interrupt_randomness(action->irq);
+
+
+ migrate_enable();
+ }
wake_threads_waitq(desc);
}
@@ -1467,8 +1479,6 @@ setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
if (IS_ERR(t))
return PTR_ERR(t);
- sched_set_fifo(t);
-
/*
* We keep the reference to the task struct even if
* the thread dies to avoid that the interrupt code
@@ -2857,7 +2867,7 @@ EXPORT_SYMBOL_GPL(irq_get_irqchip_state);
* This call sets the internal irqchip state of an interrupt,
* depending on the value of @which.
*
- * This function should be called with preemption disabled if the
+ * This function should be called with migration disabled if the
* interrupt controller has per-cpu registers.
*/
int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index f865e5f4d..dc7311dd7 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -443,6 +443,10 @@ MODULE_PARM_DESC(noirqdebug, "Disable irq lockup detection when true");
static int __init irqfixup_setup(char *str)
{
+#ifdef CONFIG_PREEMPT_RT
+ pr_warn("irqfixup boot option not supported w/ CONFIG_PREEMPT_RT\n");
+ return 1;
+#endif
irqfixup = 1;
printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n");
printk(KERN_WARNING "This may impact system performance.\n");
@@ -455,6 +459,10 @@ module_param(irqfixup, int, 0644);
static int __init irqpoll_setup(char *str)
{
+#ifdef CONFIG_PREEMPT_RT
+ pr_warn("irqpoll boot option not supported w/ CONFIG_PREEMPT_RT\n");
+ return 1;
+#endif
irqfixup = 2;
printk(KERN_WARNING "Misrouted IRQ fixup and polling support "
"enabled\n");
diff --git a/kernel/irq_work.c b/kernel/irq_work.c
index fbff25adb..d3466e3ba 100644
--- a/kernel/irq_work.c
+++ b/kernel/irq_work.c
@@ -18,11 +18,36 @@
#include <linux/cpu.h>
#include <linux/notifier.h>
#include <linux/smp.h>
+#include <linux/smpboot.h>
#include <asm/processor.h>
static DEFINE_PER_CPU(struct llist_head, raised_list);
static DEFINE_PER_CPU(struct llist_head, lazy_list);
+static DEFINE_PER_CPU(struct task_struct *, irq_workd);
+
+static void wake_irq_workd(void)
+{
+ struct task_struct *tsk = __this_cpu_read(irq_workd);
+
+ if (!llist_empty(this_cpu_ptr(&lazy_list)) && tsk)
+ wake_up_process(tsk);
+}
+
+#ifdef CONFIG_SMP
+static void irq_work_wake(struct irq_work *entry)
+{
+ wake_irq_workd();
+}
+
+static DEFINE_PER_CPU(struct irq_work, irq_work_wakeup) =
+ IRQ_WORK_INIT_HARD(irq_work_wake);
+#endif
+
+static int irq_workd_should_run(unsigned int cpu)
+{
+ return !llist_empty(this_cpu_ptr(&lazy_list));
+}
/*
* Claim the entry so that no one else will poke at it.
@@ -52,15 +77,29 @@ void __weak arch_irq_work_raise(void)
/* Enqueue on current CPU, work must already be claimed and preempt disabled */
static void __irq_work_queue_local(struct irq_work *work)
{
- /* If the work is "lazy", handle it from next tick if any */
- if (atomic_read(&work->node.a_flags) & IRQ_WORK_LAZY) {
- if (llist_add(&work->node.llist, this_cpu_ptr(&lazy_list)) &&
- tick_nohz_tick_stopped())
- arch_irq_work_raise();
- } else {
- if (llist_add(&work->node.llist, this_cpu_ptr(&raised_list)))
- arch_irq_work_raise();
- }
+ struct llist_head *list;
+ bool rt_lazy_work = false;
+ bool lazy_work = false;
+ int work_flags;
+
+ work_flags = atomic_read(&work->node.a_flags);
+ if (work_flags & IRQ_WORK_LAZY)
+ lazy_work = true;
+ else if (IS_ENABLED(CONFIG_PREEMPT_RT) &&
+ !(work_flags & IRQ_WORK_HARD_IRQ))
+ rt_lazy_work = true;
+
+ if (lazy_work || rt_lazy_work)
+ list = this_cpu_ptr(&lazy_list);
+ else
+ list = this_cpu_ptr(&raised_list);
+
+ if (!llist_add(&work->node.llist, list))
+ return;
+
+ /* If the work is "lazy", handle it from next tick if any */
+ if (!lazy_work || tick_nohz_tick_stopped())
+ arch_irq_work_raise();
}
/* Enqueue the irq work @work on the current CPU */
@@ -102,10 +141,28 @@ bool irq_work_queue_on(struct irq_work *work, int cpu)
if (cpu != smp_processor_id()) {
/* Arch remote IPI send/receive backend aren't NMI safe */
WARN_ON_ONCE(in_nmi());
- __smp_call_single_queue(cpu, &work->node.llist);
+
+ /*
+ * On PREEMPT_RT the items which are not marked as
+ * IRQ_WORK_HARD_IRQ are added to the lazy list and a HARD work
+ * item is used on the remote CPU to wake the thread.
+ */
+ if (IS_ENABLED(CONFIG_PREEMPT_RT) &&
+ !(atomic_read(&work->node.a_flags) & IRQ_WORK_HARD_IRQ)) {
+
+ if (!llist_add(&work->node.llist, &per_cpu(lazy_list, cpu)))
+ goto out;
+
+ work = &per_cpu(irq_work_wakeup, cpu);
+ if (!irq_work_claim(work))
+ goto out;
+ }
+
+ __smp_call_single_queue(cpu, &work->node.llist);
} else {
__irq_work_queue_local(work);
}
+out:
preempt_enable();
return true;
@@ -153,14 +210,23 @@ void irq_work_single(void *arg)
*/
flags &= ~IRQ_WORK_PENDING;
(void)atomic_cmpxchg(&work->node.a_flags, flags, flags & ~IRQ_WORK_BUSY);
+
+ if ((IS_ENABLED(CONFIG_PREEMPT_RT) && !irq_work_is_hard(work)) ||
+ !arch_irq_work_has_interrupt())
+ rcuwait_wake_up(&work->irqwait);
}
static void irq_work_run_list(struct llist_head *list)
{
struct irq_work *work, *tmp;
struct llist_node *llnode;
-
- BUG_ON(!irqs_disabled());
+
+ /*
+ * On PREEMPT_RT IRQ-work which is not marked as HARD will be processed
+ * in a per-CPU thread in preemptible context. Only the items which are
+ * marked as IRQ_WORK_HARD_IRQ will be processed in hardirq context.
+ */
+ BUG_ON(!irqs_disabled() && !IS_ENABLED(CONFIG_PREEMPT_RT));
if (llist_empty(list))
return;
@@ -177,7 +243,10 @@ static void irq_work_run_list(struct llist_head *list)
void irq_work_run(void)
{
irq_work_run_list(this_cpu_ptr(&raised_list));
- irq_work_run_list(this_cpu_ptr(&lazy_list));
+ if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+ irq_work_run_list(this_cpu_ptr(&lazy_list));
+ else
+ wake_irq_workd();
}
EXPORT_SYMBOL_GPL(irq_work_run);
@@ -187,7 +256,10 @@ void irq_work_tick(void)
if (!llist_empty(raised) && !arch_irq_work_has_interrupt())
irq_work_run_list(raised);
- irq_work_run_list(this_cpu_ptr(&lazy_list));
+ if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+ irq_work_run_list(this_cpu_ptr(&lazy_list));
+ else
+ wake_irq_workd();
}
/*
@@ -197,8 +269,42 @@ void irq_work_tick(void)
void irq_work_sync(struct irq_work *work)
{
lockdep_assert_irqs_enabled();
+ might_sleep();
+
+ if ((IS_ENABLED(CONFIG_PREEMPT_RT) && !irq_work_is_hard(work)) ||
+ !arch_irq_work_has_interrupt()) {
+ rcuwait_wait_event(&work->irqwait, !irq_work_is_busy(work),
+ TASK_UNINTERRUPTIBLE);
+ return;
+ }
while (irq_work_is_busy(work))
cpu_relax();
}
EXPORT_SYMBOL_GPL(irq_work_sync);
+
+static void run_irq_workd(unsigned int cpu)
+{
+ irq_work_run_list(this_cpu_ptr(&lazy_list));
+}
+
+static void irq_workd_setup(unsigned int cpu)
+{
+ sched_set_fifo_low(current);
+}
+
+static struct smp_hotplug_thread irqwork_threads = {
+ .store = &irq_workd,
+ .setup = irq_workd_setup,
+ .thread_should_run = irq_workd_should_run,
+ .thread_fn = run_irq_workd,
+ .thread_comm = "irq_work/%u",
+};
+
+static __init int irq_work_init_threads(void)
+{
+ if (IS_ENABLED(CONFIG_PREEMPT_RT))
+ BUG_ON(smpboot_register_percpu_thread(&irqwork_threads));
+ return 0;
+}
+early_initcall(irq_work_init_threads);
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index ca1a46960..dade489ea 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -984,7 +984,6 @@ void crash_kexec(struct pt_regs *regs)
old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, this_cpu);
if (old_cpu == PANIC_CPU_INVALID) {
/* This is the 1st CPU which comes here, so go ahead. */
- printk_safe_flush_on_panic();
__crash_kexec(regs);
/*
diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
index e20c19e3b..777168d58 100644
--- a/kernel/ksysfs.c
+++ b/kernel/ksysfs.c
@@ -143,6 +143,15 @@ KERNEL_ATTR_RO(vmcoreinfo);
#endif /* CONFIG_CRASH_CORE */
+#if defined(CONFIG_PREEMPT_RT)
+static ssize_t realtime_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%d\n", 1);
+}
+KERNEL_ATTR_RO(realtime);
+#endif
+
/* whether file capabilities are enabled */
static ssize_t fscaps_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
@@ -233,6 +242,9 @@ static struct attribute * kernel_attrs[] = {
#ifndef CONFIG_TINY_RCU
&rcu_expedited_attr.attr,
&rcu_normal_attr.attr,
+#endif
+#ifdef CONFIG_PREEMPT_RT
+ &realtime_attr.attr,
#endif
NULL
};
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 508fe5278..3ce6a31db 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -264,6 +264,7 @@ EXPORT_SYMBOL_GPL(kthread_parkme);
static int kthread(void *_create)
{
+ static const struct sched_param param = { .sched_priority = 0 };
/* Copy data: it's on kthread's stack */
struct kthread_create_info *create = _create;
int (*threadfn)(void *data) = create->threadfn;
@@ -294,6 +295,13 @@ static int kthread(void *_create)
init_completion(&self->parked);
current->vfork_done = &self->exited;
+ /*
+ * The new thread inherited kthreadd's priority and CPU mask. Reset
+ * back to default in case they have been changed.
+ */
+ sched_setscheduler_nocheck(current, SCHED_NORMAL, &param);
+ set_cpus_allowed_ptr(current, housekeeping_cpumask(HK_FLAG_KTHREAD));
+
/* OK, tell user we're spawned, wait for stop or wakeup */
__set_current_state(TASK_UNINTERRUPTIBLE);
create->result = current;
@@ -391,7 +399,6 @@ struct task_struct *__kthread_create_on_node(int (*threadfn)(void *data),
}
task = create->result;
if (!IS_ERR(task)) {
- static const struct sched_param param = { .sched_priority = 0 };
char name[TASK_COMM_LEN];
/*
@@ -400,13 +407,6 @@ struct task_struct *__kthread_create_on_node(int (*threadfn)(void *data),
*/
vsnprintf(name, sizeof(name), namefmt, args);
set_task_comm(task, name);
- /*
- * root may have changed our (kthreadd's) priority or CPU mask.
- * The kernel thread should not inherit these properties.
- */
- sched_setscheduler_nocheck(task, SCHED_NORMAL, &param);
- set_cpus_allowed_ptr(task,
- housekeeping_cpumask(HK_FLAG_KTHREAD));
}
kfree(create);
return task;
diff --git a/kernel/locking/Makefile b/kernel/locking/Makefile
index 6d11cfb9b..c7fbf737e 100644
--- a/kernel/locking/Makefile
+++ b/kernel/locking/Makefile
@@ -3,7 +3,7 @@
# and is generally not a function of system call inputs.
KCOV_INSTRUMENT := n
-obj-y += mutex.o semaphore.o rwsem.o percpu-rwsem.o
+obj-y += semaphore.o rwsem.o percpu-rwsem.o
# Avoid recursion lockdep -> KCSAN -> ... -> lockdep.
KCSAN_SANITIZE_lockdep.o := n
@@ -15,19 +15,23 @@ CFLAGS_REMOVE_mutex-debug.o = $(CC_FLAGS_FTRACE)
CFLAGS_REMOVE_rtmutex-debug.o = $(CC_FLAGS_FTRACE)
endif
-obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o
obj-$(CONFIG_LOCKDEP) += lockdep.o
ifeq ($(CONFIG_PROC_FS),y)
obj-$(CONFIG_LOCKDEP) += lockdep_proc.o
endif
obj-$(CONFIG_SMP) += spinlock.o
-obj-$(CONFIG_LOCK_SPIN_ON_OWNER) += osq_lock.o
obj-$(CONFIG_PROVE_LOCKING) += spinlock.o
obj-$(CONFIG_QUEUED_SPINLOCKS) += qspinlock.o
obj-$(CONFIG_RT_MUTEXES) += rtmutex.o
obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o
obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o
obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock_debug.o
+ifneq ($(CONFIG_PREEMPT_RT),y)
+obj-y += mutex.o
+obj-$(CONFIG_LOCK_SPIN_ON_OWNER) += osq_lock.o
+obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o
+endif
+obj-$(CONFIG_PREEMPT_RT) += mutex-rt.o rwsem-rt.o rwlock-rt.o
obj-$(CONFIG_QUEUED_RWLOCKS) += qrwlock.o
obj-$(CONFIG_LOCK_TORTURE_TEST) += locktorture.o
obj-$(CONFIG_WW_MUTEX_SELFTEST) += test-ww_mutex.o
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 7471d85f5..4fb9e6301 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -5414,6 +5414,7 @@ static noinstr void check_flags(unsigned long flags)
}
}
+#ifndef CONFIG_PREEMPT_RT
/*
* We dont accurately track softirq state in e.g.
* hardirq contexts (such as on 4KSTACKS), so only
@@ -5428,6 +5429,7 @@ static noinstr void check_flags(unsigned long flags)
DEBUG_LOCKS_WARN_ON(!current->softirqs_enabled);
}
}
+#endif
if (!debug_locks)
print_irqtrace_events(current);
diff --git a/kernel/locking/mutex-rt.c b/kernel/locking/mutex-rt.c
new file mode 100644
index 000000000..2b849e6b9
--- /dev/null
+++ b/kernel/locking/mutex-rt.c
@@ -0,0 +1,224 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Real-Time Preemption Support
+ *
+ * started by Ingo Molnar:
+ *
+ * Copyright (C) 2004-2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
+ * Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com>
+ *
+ * historic credit for proving that Linux spinlocks can be implemented via
+ * RT-aware mutexes goes to many people: The Pmutex project (Dirk Grambow
+ * and others) who prototyped it on 2.4 and did lots of comparative
+ * research and analysis; TimeSys, for proving that you can implement a
+ * fully preemptible kernel via the use of IRQ threading and mutexes;
+ * Bill Huey for persuasively arguing on lkml that the mutex model is the
+ * right one; and to MontaVista, who ported pmutexes to 2.6.
+ *
+ * This code is a from-scratch implementation and is not based on pmutexes,
+ * but the idea of converting spinlocks to mutexes is used here too.
+ *
+ * lock debugging, locking tree, deadlock detection:
+ *
+ * Copyright (C) 2004, LynuxWorks, Inc., Igor Manyilov, Bill Huey
+ * Released under the General Public License (GPL).
+ *
+ * Includes portions of the generic R/W semaphore implementation from:
+ *
+ * Copyright (c) 2001 David Howells (dhowells@redhat.com).
+ * - Derived partially from idea by Andrea Arcangeli <andrea@suse.de>
+ * - Derived also from comments by Linus
+ *
+ * Pending ownership of locks and ownership stealing:
+ *
+ * Copyright (C) 2005, Kihon Technologies Inc., Steven Rostedt
+ *
+ * (also by Steven Rostedt)
+ * - Converted single pi_lock to individual task locks.
+ *
+ * By Esben Nielsen:
+ * Doing priority inheritance with help of the scheduler.
+ *
+ * Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com>
+ * - major rework based on Esben Nielsens initial patch
+ * - replaced thread_info references by task_struct refs
+ * - removed task->pending_owner dependency
+ * - BKL drop/reacquire for semaphore style locks to avoid deadlocks
+ * in the scheduler return path as discussed with Steven Rostedt
+ *
+ * Copyright (C) 2006, Kihon Technologies Inc.
+ * Steven Rostedt <rostedt@goodmis.org>
+ * - debugged and patched Thomas Gleixner's rework.
+ * - added back the cmpxchg to the rework.
+ * - turned atomic require back on for SMP.
+ */
+
+#include <linux/spinlock.h>
+#include <linux/rtmutex.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/kallsyms.h>
+#include <linux/syscalls.h>
+#include <linux/interrupt.h>
+#include <linux/plist.h>
+#include <linux/fs.h>
+#include <linux/futex.h>
+#include <linux/hrtimer.h>
+#include <linux/blkdev.h>
+
+#include "rtmutex_common.h"
+
+/*
+ * struct mutex functions
+ */
+void __mutex_do_init(struct mutex *mutex, const char *name,
+ struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ /*
+ * Make sure we are not reinitializing a held lock:
+ */
+ debug_check_no_locks_freed((void *)mutex, sizeof(*mutex));
+ lockdep_init_map(&mutex->dep_map, name, key, 0);
+#endif
+ mutex->lock.save_state = 0;
+}
+EXPORT_SYMBOL(__mutex_do_init);
+
+static int _mutex_lock_blk_flush(struct mutex *lock, int state)
+{
+ /*
+ * Flush blk before ->pi_blocked_on is set. At schedule() time it is too
+ * late if one of the callbacks needs to acquire a sleeping lock.
+ */
+ if (blk_needs_flush_plug(current))
+ blk_schedule_flush_plug(current);
+ return __rt_mutex_lock_state(&lock->lock, state);
+}
+
+void __lockfunc _mutex_lock(struct mutex *lock)
+{
+ mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+ _mutex_lock_blk_flush(lock, TASK_UNINTERRUPTIBLE);
+}
+EXPORT_SYMBOL(_mutex_lock);
+
+void __lockfunc _mutex_lock_io_nested(struct mutex *lock, int subclass)
+{
+ int token;
+
+ token = io_schedule_prepare();
+
+ mutex_acquire_nest(&lock->dep_map, subclass, 0, NULL, _RET_IP_);
+ __rt_mutex_lock_state(&lock->lock, TASK_UNINTERRUPTIBLE);
+
+ io_schedule_finish(token);
+}
+EXPORT_SYMBOL_GPL(_mutex_lock_io_nested);
+
+int __lockfunc _mutex_lock_interruptible(struct mutex *lock)
+{
+ int ret;
+
+ mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+ ret = _mutex_lock_blk_flush(lock, TASK_INTERRUPTIBLE);
+ if (ret)
+ mutex_release(&lock->dep_map, _RET_IP_);
+ return ret;
+}
+EXPORT_SYMBOL(_mutex_lock_interruptible);
+
+int __lockfunc _mutex_lock_killable(struct mutex *lock)
+{
+ int ret;
+
+ mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+ ret = _mutex_lock_blk_flush(lock, TASK_KILLABLE);
+ if (ret)
+ mutex_release(&lock->dep_map, _RET_IP_);
+ return ret;
+}
+EXPORT_SYMBOL(_mutex_lock_killable);
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+void __lockfunc _mutex_lock_nested(struct mutex *lock, int subclass)
+{
+ mutex_acquire_nest(&lock->dep_map, subclass, 0, NULL, _RET_IP_);
+ _mutex_lock_blk_flush(lock, TASK_UNINTERRUPTIBLE);
+}
+EXPORT_SYMBOL(_mutex_lock_nested);
+
+void __lockfunc _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest)
+{
+ mutex_acquire_nest(&lock->dep_map, 0, 0, nest, _RET_IP_);
+ _mutex_lock_blk_flush(lock, TASK_UNINTERRUPTIBLE);
+}
+EXPORT_SYMBOL(_mutex_lock_nest_lock);
+
+int __lockfunc _mutex_lock_interruptible_nested(struct mutex *lock, int subclass)
+{
+ int ret;
+
+ mutex_acquire_nest(&lock->dep_map, subclass, 0, NULL, _RET_IP_);
+ ret = _mutex_lock_blk_flush(lock, TASK_INTERRUPTIBLE);
+ if (ret)
+ mutex_release(&lock->dep_map, _RET_IP_);
+ return ret;
+}
+EXPORT_SYMBOL(_mutex_lock_interruptible_nested);
+
+int __lockfunc _mutex_lock_killable_nested(struct mutex *lock, int subclass)
+{
+ int ret;
+
+ mutex_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
+ ret = _mutex_lock_blk_flush(lock, TASK_KILLABLE);
+ if (ret)
+ mutex_release(&lock->dep_map, _RET_IP_);
+ return ret;
+}
+EXPORT_SYMBOL(_mutex_lock_killable_nested);
+#endif
+
+int __lockfunc _mutex_trylock(struct mutex *lock)
+{
+ int ret = __rt_mutex_trylock(&lock->lock);
+
+ if (ret)
+ mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+
+ return ret;
+}
+EXPORT_SYMBOL(_mutex_trylock);
+
+void __lockfunc _mutex_unlock(struct mutex *lock)
+{
+ mutex_release(&lock->dep_map, _RET_IP_);
+ __rt_mutex_unlock(&lock->lock);
+}
+EXPORT_SYMBOL(_mutex_unlock);
+
+/**
+ * atomic_dec_and_mutex_lock - return holding mutex if we dec to 0
+ * @cnt: the atomic which we are to dec
+ * @lock: the mutex to return holding if we dec to 0
+ *
+ * return true and hold lock if we dec to 0, return false otherwise
+ */
+int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock)
+{
+ /* dec if we can't possibly hit 0 */
+ if (atomic_add_unless(cnt, -1, 1))
+ return 0;
+ /* we might hit 0, so take the lock */
+ mutex_lock(lock);
+ if (!atomic_dec_and_test(cnt)) {
+ /* when we actually did the dec, we didn't hit 0 */
+ mutex_unlock(lock);
+ return 0;
+ }
+ /* we hit 0, and we hold the lock */
+ return 1;
+}
+EXPORT_SYMBOL(atomic_dec_and_mutex_lock);
diff --git a/kernel/locking/rtmutex-debug.c b/kernel/locking/rtmutex-debug.c
index 36e69100e..fb1501003 100644
--- a/kernel/locking/rtmutex-debug.c
+++ b/kernel/locking/rtmutex-debug.c
@@ -32,110 +32,12 @@
#include "rtmutex_common.h"
-static void printk_task(struct task_struct *p)
-{
- if (p)
- printk("%16s:%5d [%p, %3d]", p->comm, task_pid_nr(p), p, p->prio);
- else
- printk("<none>");
-}
-
-static void printk_lock(struct rt_mutex *lock, int print_owner)
-{
- if (lock->name)
- printk(" [%p] {%s}\n",
- lock, lock->name);
- else
- printk(" [%p] {%s:%d}\n",
- lock, lock->file, lock->line);
-
- if (print_owner && rt_mutex_owner(lock)) {
- printk(".. ->owner: %p\n", lock->owner);
- printk(".. held by: ");
- printk_task(rt_mutex_owner(lock));
- printk("\n");
- }
-}
-
void rt_mutex_debug_task_free(struct task_struct *task)
{
DEBUG_LOCKS_WARN_ON(!RB_EMPTY_ROOT(&task->pi_waiters.rb_root));
DEBUG_LOCKS_WARN_ON(task->pi_blocked_on);
}
-/*
- * We fill out the fields in the waiter to store the information about
- * the deadlock. We print when we return. act_waiter can be NULL in
- * case of a remove waiter operation.
- */
-void debug_rt_mutex_deadlock(enum rtmutex_chainwalk chwalk,
- struct rt_mutex_waiter *act_waiter,
- struct rt_mutex *lock)
-{
- struct task_struct *task;
-
- if (!debug_locks || chwalk == RT_MUTEX_FULL_CHAINWALK || !act_waiter)
- return;
-
- task = rt_mutex_owner(act_waiter->lock);
- if (task && task != current) {
- act_waiter->deadlock_task_pid = get_pid(task_pid(task));
- act_waiter->deadlock_lock = lock;
- }
-}
-
-void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter)
-{
- struct task_struct *task;
-
- if (!waiter->deadlock_lock || !debug_locks)
- return;
-
- rcu_read_lock();
- task = pid_task(waiter->deadlock_task_pid, PIDTYPE_PID);
- if (!task) {
- rcu_read_unlock();
- return;
- }
-
- if (!debug_locks_off()) {
- rcu_read_unlock();
- return;
- }
-
- pr_warn("\n");
- pr_warn("============================================\n");
- pr_warn("WARNING: circular locking deadlock detected!\n");
- pr_warn("%s\n", print_tainted());
- pr_warn("--------------------------------------------\n");
- printk("%s/%d is deadlocking current task %s/%d\n\n",
- task->comm, task_pid_nr(task),
- current->comm, task_pid_nr(current));
-
- printk("\n1) %s/%d is trying to acquire this lock:\n",
- current->comm, task_pid_nr(current));
- printk_lock(waiter->lock, 1);
-
- printk("\n2) %s/%d is blocked on this lock:\n",
- task->comm, task_pid_nr(task));
- printk_lock(waiter->deadlock_lock, 1);
-
- debug_show_held_locks(current);
- debug_show_held_locks(task);
-
- printk("\n%s/%d's [blocked] stackdump:\n\n",
- task->comm, task_pid_nr(task));
- show_stack(task, NULL, KERN_DEFAULT);
- printk("\n%s/%d's [current] stackdump:\n\n",
- current->comm, task_pid_nr(current));
- dump_stack();
- debug_show_all_locks();
- rcu_read_unlock();
-
- printk("[ turning off deadlock detection."
- "Please report this trace. ]\n\n");
-}
-
void debug_rt_mutex_lock(struct rt_mutex *lock)
{
}
@@ -158,12 +60,10 @@ void debug_rt_mutex_proxy_unlock(struct rt_mutex *lock)
void debug_rt_mutex_init_waiter(struct rt_mutex_waiter *waiter)
{
memset(waiter, 0x11, sizeof(*waiter));
- waiter->deadlock_task_pid = NULL;
}
void debug_rt_mutex_free_waiter(struct rt_mutex_waiter *waiter)
{
- put_pid(waiter->deadlock_task_pid);
memset(waiter, 0x22, sizeof(*waiter));
}
@@ -173,10 +73,8 @@ void debug_rt_mutex_init(struct rt_mutex *lock, const char *name, struct lock_cl
* Make sure we are not reinitializing a held lock:
*/
debug_check_no_locks_freed((void *)lock, sizeof(*lock));
- lock->name = name;
#ifdef CONFIG_DEBUG_LOCK_ALLOC
lockdep_init_map(&lock->dep_map, name, key, 0);
#endif
}
-
diff --git a/kernel/locking/rtmutex-debug.h b/kernel/locking/rtmutex-debug.h
index fc549713b..659e93e25 100644
--- a/kernel/locking/rtmutex-debug.h
+++ b/kernel/locking/rtmutex-debug.h
@@ -18,20 +18,9 @@ extern void debug_rt_mutex_unlock(struct rt_mutex *lock);
extern void debug_rt_mutex_proxy_lock(struct rt_mutex *lock,
struct task_struct *powner);
extern void debug_rt_mutex_proxy_unlock(struct rt_mutex *lock);
-extern void debug_rt_mutex_deadlock(enum rtmutex_chainwalk chwalk,
- struct rt_mutex_waiter *waiter,
- struct rt_mutex *lock);
-extern void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter);
-# define debug_rt_mutex_reset_waiter(w) \
- do { (w)->deadlock_lock = NULL; } while (0)
static inline bool debug_rt_mutex_detect_deadlock(struct rt_mutex_waiter *waiter,
enum rtmutex_chainwalk walk)
{
return (waiter != NULL);
}
-
-static inline void rt_mutex_print_deadlock(struct rt_mutex_waiter *w)
-{
- debug_rt_mutex_print_deadlock(w);
-}
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index b909b559a..dd68a5665 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -8,6 +8,11 @@
* Copyright (C) 2005-2006 Timesys Corp., Thomas Gleixner <tglx@timesys.com>
* Copyright (C) 2005 Kihon Technologies Inc., Steven Rostedt
* Copyright (C) 2006 Esben Nielsen
+ * Adaptive Spinlocks:
+ * Copyright (C) 2008 Novell, Inc., Gregory Haskins, Sven Dietrich,
+ * and Peter Morreale,
+ * Adaptive Spinlocks simplification:
+ * Copyright (C) 2008 Red Hat, Inc., Steven Rostedt <srostedt@redhat.com>
*
* See Documentation/locking/rt-mutex-design.rst for details.
*/
@@ -19,6 +24,7 @@
#include <linux/sched/wake_q.h>
#include <linux/sched/debug.h>
#include <linux/timer.h>
+#include <linux/ww_mutex.h>
#include "rtmutex_common.h"
@@ -164,6 +170,11 @@ static void fixup_rt_mutex_waiters(struct rt_mutex *lock, bool acquire_lock)
WRITE_ONCE(*p, owner & ~RT_MUTEX_HAS_WAITERS);
}
}
+static int rt_mutex_real_waiter(struct rt_mutex_waiter *waiter)
+{
+ return waiter && waiter != PI_WAKEUP_INPROGRESS &&
+ waiter != PI_REQUEUE_INPROGRESS;
+}
/*
* We can speed up the acquire/release, if there's no debugging state to be
@@ -263,7 +274,7 @@ static inline bool unlock_rt_mutex_safe(struct rt_mutex *lock,
* Only use with rt_mutex_waiter_{less,equal}()
*/
#define task_to_waiter(p) \
- &(struct rt_mutex_waiter){ .prio = (p)->prio, .deadline = (p)->dl.deadline }
+ &(struct rt_mutex_waiter){ .prio = (p)->prio, .deadline = (p)->dl.deadline, .task = (p) }
static inline int
rt_mutex_waiter_less(struct rt_mutex_waiter *left,
@@ -311,6 +322,27 @@ static inline bool __waiter_less(struct rb_node *a, const struct rb_node *b)
return rt_mutex_waiter_less(__node_2_waiter(a), __node_2_waiter(b));
}
+#define STEAL_NORMAL 0
+#define STEAL_LATERAL 1
+
+static inline int
+rt_mutex_steal(struct rt_mutex *lock, struct rt_mutex_waiter *waiter, int mode)
+{
+ struct rt_mutex_waiter *top_waiter = rt_mutex_top_waiter(lock);
+
+ if (waiter == top_waiter || rt_mutex_waiter_less(waiter, top_waiter))
+ return 1;
+
+ /*
+ * Note that RT tasks are excluded from lateral-steals
+ * to prevent the introduction of an unbounded latency.
+ */
+ if (mode == STEAL_NORMAL || rt_task(waiter->task))
+ return 0;
+
+ return rt_mutex_waiter_equal(waiter, top_waiter);
+}
+
static void
rt_mutex_enqueue(struct rt_mutex *lock, struct rt_mutex_waiter *waiter)
{
@@ -389,6 +421,14 @@ static bool rt_mutex_cond_detect_deadlock(struct rt_mutex_waiter *waiter,
return debug_rt_mutex_detect_deadlock(waiter, chwalk);
}
+static void rt_mutex_wake_waiter(struct rt_mutex_waiter *waiter)
+{
+ if (waiter->savestate)
+ wake_up_lock_sleeper(waiter->task);
+ else
+ wake_up_process(waiter->task);
+}
+
/*
* Max number of times we'll walk the boosting chain:
*/
@@ -396,7 +436,8 @@ int max_lock_depth = 1024;
static inline struct rt_mutex *task_blocked_on_lock(struct task_struct *p)
{
- return p->pi_blocked_on ? p->pi_blocked_on->lock : NULL;
+ return rt_mutex_real_waiter(p->pi_blocked_on) ?
+ p->pi_blocked_on->lock : NULL;
}
/*
@@ -532,7 +573,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
* reached or the state of the chain has changed while we
* dropped the locks.
*/
- if (!waiter)
+ if (!rt_mutex_real_waiter(waiter))
goto out_unlock_pi;
/*
@@ -615,7 +656,6 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
* walk, we detected a deadlock.
*/
if (lock == orig_lock || rt_mutex_owner(lock) == top_task) {
- debug_rt_mutex_deadlock(chwalk, orig_waiter, lock);
raw_spin_unlock(&lock->wait_lock);
ret = -EDEADLK;
goto out_unlock_pi;
@@ -712,13 +752,16 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
* follow here. This is the end of the chain we are walking.
*/
if (!rt_mutex_owner(lock)) {
+ struct rt_mutex_waiter *lock_top_waiter;
+
/*
* If the requeue [7] above changed the top waiter,
* then we need to wake the new top waiter up to try
* to get the lock.
*/
- if (prerequeue_top_waiter != rt_mutex_top_waiter(lock))
- wake_up_process(rt_mutex_top_waiter(lock)->task);
+ lock_top_waiter = rt_mutex_top_waiter(lock);
+ if (prerequeue_top_waiter != lock_top_waiter)
+ rt_mutex_wake_waiter(lock_top_waiter);
raw_spin_unlock_irq(&lock->wait_lock);
return 0;
}
@@ -819,9 +862,11 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
* @task: The task which wants to acquire the lock
* @waiter: The waiter that is queued to the lock's wait tree if the
* callsite called task_blocked_on_lock(), otherwise NULL
+ * @mode: Lock steal mode (STEAL_NORMAL, STEAL_LATERAL)
*/
-static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
- struct rt_mutex_waiter *waiter)
+static int __try_to_take_rt_mutex(struct rt_mutex *lock,
+ struct task_struct *task,
+ struct rt_mutex_waiter *waiter, int mode)
{
lockdep_assert_held(&lock->wait_lock);
@@ -857,12 +902,11 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
*/
if (waiter) {
/*
- * If waiter is not the highest priority waiter of
- * @lock, give up.
+ * If waiter is not the highest priority waiter of @lock,
+ * or its peer when lateral steal is allowed, give up.
*/
- if (waiter != rt_mutex_top_waiter(lock))
+ if (!rt_mutex_steal(lock, waiter, mode))
return 0;
-
/*
* We can acquire the lock. Remove the waiter from the
* lock waiters tree.
@@ -880,14 +924,12 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
*/
if (rt_mutex_has_waiters(lock)) {
/*
- * If @task->prio is greater than or equal to
- * the top waiter priority (kernel view),
- * @task lost.
+ * If @task->prio is greater than the top waiter
+ * priority (kernel view), or equal to it when a
+ * lateral steal is forbidden, @task lost.
*/
- if (!rt_mutex_waiter_less(task_to_waiter(task),
- rt_mutex_top_waiter(lock)))
+ if (!rt_mutex_steal(lock, task_to_waiter(task), mode))
return 0;
-
/*
* The current top waiter stays enqueued. We
* don't have to change anything in the lock
@@ -934,6 +976,329 @@ takeit:
return 1;
}
+#ifdef CONFIG_PREEMPT_RT
+/*
+ * preemptible spin_lock functions:
+ */
+static inline void rt_spin_lock_fastlock(struct rt_mutex *lock,
+ void (*slowfn)(struct rt_mutex *lock))
+{
+ might_sleep_no_state_check();
+
+ if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
+ return;
+ else
+ slowfn(lock);
+}
+
+static inline void rt_spin_lock_fastunlock(struct rt_mutex *lock,
+ void (*slowfn)(struct rt_mutex *lock))
+{
+ if (likely(rt_mutex_cmpxchg_release(lock, current, NULL)))
+ return;
+ else
+ slowfn(lock);
+}
+#ifdef CONFIG_SMP
+/*
+ * Note that owner is a speculative pointer and dereferencing relies
+ * on rcu_read_lock() and the check against the lock owner.
+ */
+static int adaptive_wait(struct rt_mutex *lock,
+ struct task_struct *owner)
+{
+ int res = 0;
+
+ rcu_read_lock();
+ for (;;) {
+ if (owner != rt_mutex_owner(lock))
+ break;
+ /*
+ * Ensure that owner->on_cpu is dereferenced _after_
+ * checking the above to be valid.
+ */
+ barrier();
+ if (!owner->on_cpu) {
+ res = 1;
+ break;
+ }
+ cpu_relax();
+ }
+ rcu_read_unlock();
+ return res;
+}
+#else
+static int adaptive_wait(struct rt_mutex *lock,
+ struct task_struct *orig_owner)
+{
+ return 1;
+}
+#endif
+
+static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
+ struct rt_mutex_waiter *waiter,
+ struct task_struct *task,
+ enum rtmutex_chainwalk chwalk);
+/*
+ * Slow path lock function spin_lock style: this variant is very
+ * careful not to miss any non-lock wakeups.
+ *
+ * We store the current state under p->pi_lock in p->saved_state and
+ * the try_to_wake_up() code handles this accordingly.
+ */
+void __sched rt_spin_lock_slowlock_locked(struct rt_mutex *lock,
+ struct rt_mutex_waiter *waiter,
+ unsigned long flags)
+{
+ struct task_struct *lock_owner, *self = current;
+ struct rt_mutex_waiter *top_waiter;
+ int ret;
+
+ if (__try_to_take_rt_mutex(lock, self, NULL, STEAL_LATERAL))
+ return;
+
+ BUG_ON(rt_mutex_owner(lock) == self);
+
+ /*
+ * We save whatever state the task is in and we'll restore it
+ * after acquiring the lock taking real wakeups into account
+ * as well. We are serialized via pi_lock against wakeups. See
+ * try_to_wake_up().
+ */
+ raw_spin_lock(&self->pi_lock);
+ self->saved_state = self->state;
+ __set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+ raw_spin_unlock(&self->pi_lock);
+
+ ret = task_blocks_on_rt_mutex(lock, waiter, self, RT_MUTEX_MIN_CHAINWALK);
+ BUG_ON(ret);
+
+ for (;;) {
+ /* Try to acquire the lock again. */
+ if (__try_to_take_rt_mutex(lock, self, waiter, STEAL_LATERAL))
+ break;
+
+ top_waiter = rt_mutex_top_waiter(lock);
+ lock_owner = rt_mutex_owner(lock);
+
+ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+
+ if (top_waiter != waiter || adaptive_wait(lock, lock_owner))
+ preempt_schedule_lock();
+
+ raw_spin_lock_irqsave(&lock->wait_lock, flags);
+
+ raw_spin_lock(&self->pi_lock);
+ __set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+ raw_spin_unlock(&self->pi_lock);
+ }
+
+ /*
+ * Restore the task state to current->saved_state. We set it
+ * to the original state above and the try_to_wake_up() code
+ * has possibly updated it when a real (non-rtmutex) wakeup
+ * happened while we were blocked. Clear saved_state so
+ * try_to_wakeup() does not get confused.
+ */
+ raw_spin_lock(&self->pi_lock);
+ __set_current_state_no_track(self->saved_state);
+ self->saved_state = TASK_RUNNING;
+ raw_spin_unlock(&self->pi_lock);
+
+ /*
+ * try_to_take_rt_mutex() sets the waiter bit
+ * unconditionally. We might have to fix that up:
+ */
+ fixup_rt_mutex_waiters(lock, true);
+
+ BUG_ON(rt_mutex_has_waiters(lock) && waiter == rt_mutex_top_waiter(lock));
+ BUG_ON(!RB_EMPTY_NODE(&waiter->tree_entry));
+}
+
+static void noinline __sched rt_spin_lock_slowlock(struct rt_mutex *lock)
+{
+ struct rt_mutex_waiter waiter;
+ unsigned long flags;
+
+ rt_mutex_init_waiter(&waiter, true);
+
+ raw_spin_lock_irqsave(&lock->wait_lock, flags);
+ rt_spin_lock_slowlock_locked(lock, &waiter, flags);
+ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+ debug_rt_mutex_free_waiter(&waiter);
+}
+
+static bool __sched __rt_mutex_unlock_common(struct rt_mutex *lock,
+ struct wake_q_head *wake_q,
+ struct wake_q_head *wq_sleeper);
+/*
+ * Slow path to release a rt_mutex spin_lock style
+ */
+void __sched rt_spin_lock_slowunlock(struct rt_mutex *lock)
+{
+ unsigned long flags;
+ DEFINE_WAKE_Q(wake_q);
+ DEFINE_WAKE_Q(wake_sleeper_q);
+ bool postunlock;
+
+ raw_spin_lock_irqsave(&lock->wait_lock, flags);
+ postunlock = __rt_mutex_unlock_common(lock, &wake_q, &wake_sleeper_q);
+ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+
+ if (postunlock)
+ rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
+}
+
+void __lockfunc rt_spin_lock(spinlock_t *lock)
+{
+ spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+ rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock);
+ rcu_read_lock();
+ migrate_disable();
+}
+EXPORT_SYMBOL(rt_spin_lock);
+
+void __lockfunc __rt_spin_lock(struct rt_mutex *lock)
+{
+ rt_spin_lock_fastlock(lock, rt_spin_lock_slowlock);
+}
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+void __lockfunc rt_spin_lock_nested(spinlock_t *lock, int subclass)
+{
+ spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
+ rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock);
+ rcu_read_lock();
+ migrate_disable();
+}
+EXPORT_SYMBOL(rt_spin_lock_nested);
+
+void __lockfunc rt_spin_lock_nest_lock(spinlock_t *lock,
+ struct lockdep_map *nest_lock)
+{
+ spin_acquire_nest(&lock->dep_map, 0, 0, nest_lock, _RET_IP_);
+ rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock);
+ rcu_read_lock();
+ migrate_disable();
+}
+EXPORT_SYMBOL(rt_spin_lock_nest_lock);
+#endif
+
+void __lockfunc rt_spin_unlock(spinlock_t *lock)
+{
+ /* NOTE: we always pass in '1' for nested, for simplicity */
+ spin_release(&lock->dep_map, _RET_IP_);
+ migrate_enable();
+ rcu_read_unlock();
+ rt_spin_lock_fastunlock(&lock->lock, rt_spin_lock_slowunlock);
+}
+EXPORT_SYMBOL(rt_spin_unlock);
+
+void __lockfunc __rt_spin_unlock(struct rt_mutex *lock)
+{
+ rt_spin_lock_fastunlock(lock, rt_spin_lock_slowunlock);
+}
+EXPORT_SYMBOL(__rt_spin_unlock);
+
+/*
+ * Wait for the lock to get unlocked: instead of polling for an unlock
+ * (like raw spinlocks do), we lock and unlock, to force the kernel to
+ * schedule if there's contention:
+ */
+void __lockfunc rt_spin_lock_unlock(spinlock_t *lock)
+{
+ spin_lock(lock);
+ spin_unlock(lock);
+}
+EXPORT_SYMBOL(rt_spin_lock_unlock);
+
+int __lockfunc rt_spin_trylock(spinlock_t *lock)
+{
+ int ret;
+
+ ret = __rt_mutex_trylock(&lock->lock);
+ if (ret) {
+ spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+ rcu_read_lock();
+ migrate_disable();
+ }
+ return ret;
+}
+EXPORT_SYMBOL(rt_spin_trylock);
+
+int __lockfunc rt_spin_trylock_bh(spinlock_t *lock)
+{
+ int ret;
+
+ local_bh_disable();
+ ret = __rt_mutex_trylock(&lock->lock);
+ if (ret) {
+ spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+ rcu_read_lock();
+ migrate_disable();
+ } else {
+ local_bh_enable();
+ }
+ return ret;
+}
+EXPORT_SYMBOL(rt_spin_trylock_bh);
+
+void
+__rt_spin_lock_init(spinlock_t *lock, const char *name, struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ /*
+ * Make sure we are not reinitializing a held lock:
+ */
+ debug_check_no_locks_freed((void *)lock, sizeof(*lock));
+ lockdep_init_map(&lock->dep_map, name, key, 0);
+#endif
+}
+EXPORT_SYMBOL(__rt_spin_lock_init);
+
+#endif /* PREEMPT_RT */
+
+#ifdef CONFIG_PREEMPT_RT
+ static inline int __sched
+__mutex_lock_check_stamp(struct rt_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+ struct ww_mutex *ww = container_of(lock, struct ww_mutex, base.lock);
+ struct ww_acquire_ctx *hold_ctx = READ_ONCE(ww->ctx);
+
+ if (!hold_ctx)
+ return 0;
+
+ if (unlikely(ctx == hold_ctx))
+ return -EALREADY;
+
+ if (ctx->stamp - hold_ctx->stamp <= LONG_MAX &&
+ (ctx->stamp != hold_ctx->stamp || ctx > hold_ctx)) {
+#ifdef CONFIG_DEBUG_MUTEXES
+ DEBUG_LOCKS_WARN_ON(ctx->contending_lock);
+ ctx->contending_lock = ww;
+#endif
+ return -EDEADLK;
+ }
+
+ return 0;
+}
+#else
+ static inline int __sched
+__mutex_lock_check_stamp(struct rt_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+ BUG();
+ return 0;
+}
+
+#endif
+
+static inline int
+try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
+ struct rt_mutex_waiter *waiter)
+{
+ return __try_to_take_rt_mutex(lock, task, waiter, STEAL_NORMAL);
+}
+
/*
* Task blocks on lock.
*
@@ -966,6 +1331,22 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
return -EDEADLK;
raw_spin_lock(&task->pi_lock);
+ /*
+ * In the case of futex requeue PI, this will be a proxy
+ * lock. The task will wake unaware that it is enqueueed on
+ * this lock. Avoid blocking on two locks and corrupting
+ * pi_blocked_on via the PI_WAKEUP_INPROGRESS
+ * flag. futex_wait_requeue_pi() sets this when it wakes up
+ * before requeue (due to a signal or timeout). Do not enqueue
+ * the task if PI_WAKEUP_INPROGRESS is set.
+ */
+ if (task != current && task->pi_blocked_on == PI_WAKEUP_INPROGRESS) {
+ raw_spin_unlock(&task->pi_lock);
+ return -EAGAIN;
+ }
+
+ BUG_ON(rt_mutex_real_waiter(task->pi_blocked_on));
+
waiter->task = task;
waiter->lock = lock;
waiter->prio = task->prio;
@@ -989,7 +1370,7 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
rt_mutex_enqueue_pi(owner, waiter);
rt_mutex_adjust_prio(owner);
- if (owner->pi_blocked_on)
+ if (rt_mutex_real_waiter(owner->pi_blocked_on))
chain_walk = 1;
} else if (rt_mutex_cond_detect_deadlock(waiter, chwalk)) {
chain_walk = 1;
@@ -1031,6 +1412,7 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
* Called with lock->wait_lock held and interrupts disabled.
*/
static void mark_wakeup_next_waiter(struct wake_q_head *wake_q,
+ struct wake_q_head *wake_sleeper_q,
struct rt_mutex *lock)
{
struct rt_mutex_waiter *waiter;
@@ -1070,7 +1452,10 @@ static void mark_wakeup_next_waiter(struct wake_q_head *wake_q,
* Pairs with preempt_enable() in rt_mutex_postunlock();
*/
preempt_disable();
- wake_q_add(wake_q, waiter->task);
+ if (waiter->savestate)
+ wake_q_add_sleeper(wake_sleeper_q, waiter->task);
+ else
+ wake_q_add(wake_q, waiter->task);
raw_spin_unlock(&current->pi_lock);
}
@@ -1085,7 +1470,7 @@ static void remove_waiter(struct rt_mutex *lock,
{
bool is_top_waiter = (waiter == rt_mutex_top_waiter(lock));
struct task_struct *owner = rt_mutex_owner(lock);
- struct rt_mutex *next_lock;
+ struct rt_mutex *next_lock = NULL;
lockdep_assert_held(&lock->wait_lock);
@@ -1111,7 +1496,8 @@ static void remove_waiter(struct rt_mutex *lock,
rt_mutex_adjust_prio(owner);
/* Store the lock on which owner is blocked or NULL */
- next_lock = task_blocked_on_lock(owner);
+ if (rt_mutex_real_waiter(owner->pi_blocked_on))
+ next_lock = task_blocked_on_lock(owner);
raw_spin_unlock(&owner->pi_lock);
@@ -1147,26 +1533,28 @@ void rt_mutex_adjust_pi(struct task_struct *task)
raw_spin_lock_irqsave(&task->pi_lock, flags);
waiter = task->pi_blocked_on;
- if (!waiter || rt_mutex_waiter_equal(waiter, task_to_waiter(task))) {
+ if (!rt_mutex_real_waiter(waiter) ||
+ rt_mutex_waiter_equal(waiter, task_to_waiter(task))) {
raw_spin_unlock_irqrestore(&task->pi_lock, flags);
return;
}
next_lock = waiter->lock;
- raw_spin_unlock_irqrestore(&task->pi_lock, flags);
/* gets dropped in rt_mutex_adjust_prio_chain()! */
get_task_struct(task);
+ raw_spin_unlock_irqrestore(&task->pi_lock, flags);
rt_mutex_adjust_prio_chain(task, RT_MUTEX_MIN_CHAINWALK, NULL,
next_lock, NULL, task);
}
-void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter)
+void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter, bool savestate)
{
debug_rt_mutex_init_waiter(waiter);
RB_CLEAR_NODE(&waiter->pi_tree_entry);
RB_CLEAR_NODE(&waiter->tree_entry);
waiter->task = NULL;
+ waiter->savestate = savestate;
}
/**
@@ -1182,7 +1570,8 @@ void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter)
static int __sched
__rt_mutex_slowlock(struct rt_mutex *lock, int state,
struct hrtimer_sleeper *timeout,
- struct rt_mutex_waiter *waiter)
+ struct rt_mutex_waiter *waiter,
+ struct ww_acquire_ctx *ww_ctx)
{
int ret = 0;
@@ -1191,24 +1580,23 @@ __rt_mutex_slowlock(struct rt_mutex *lock, int state,
if (try_to_take_rt_mutex(lock, current, waiter))
break;
- /*
- * TASK_INTERRUPTIBLE checks for signals and
- * timeout. Ignored otherwise.
- */
- if (likely(state == TASK_INTERRUPTIBLE)) {
- /* Signal pending? */
- if (signal_pending(current))
- ret = -EINTR;
- if (timeout && !timeout->task)
- ret = -ETIMEDOUT;
+ if (timeout && !timeout->task) {
+ ret = -ETIMEDOUT;
+ break;
+ }
+ if (signal_pending_state(state, current)) {
+ ret = -EINTR;
+ break;
+ }
+
+ if (ww_ctx && ww_ctx->acquired > 0) {
+ ret = __mutex_lock_check_stamp(lock, ww_ctx);
if (ret)
break;
}
raw_spin_unlock_irq(&lock->wait_lock);
- debug_rt_mutex_print_deadlock(waiter);
-
schedule();
raw_spin_lock_irq(&lock->wait_lock);
@@ -1231,43 +1619,110 @@ static void rt_mutex_handle_deadlock(int res, int detect_deadlock,
return;
raw_spin_unlock_irq(&lock->wait_lock);
- /*
- * Yell lowdly and stop the task right here.
- */
- rt_mutex_print_deadlock(w);
while (1) {
set_current_state(TASK_INTERRUPTIBLE);
schedule();
}
}
-/*
- * Slow path lock function:
- */
-static int __sched
-rt_mutex_slowlock(struct rt_mutex *lock, int state,
- struct hrtimer_sleeper *timeout,
- enum rtmutex_chainwalk chwalk)
+static __always_inline void ww_mutex_lock_acquired(struct ww_mutex *ww,
+ struct ww_acquire_ctx *ww_ctx)
{
- struct rt_mutex_waiter waiter;
- unsigned long flags;
- int ret = 0;
+#ifdef CONFIG_DEBUG_MUTEXES
+ /*
+ * If this WARN_ON triggers, you used ww_mutex_lock to acquire,
+ * but released with a normal mutex_unlock in this call.
+ *
+ * This should never happen, always use ww_mutex_unlock.
+ */
+ DEBUG_LOCKS_WARN_ON(ww->ctx);
+
+ /*
+ * Not quite done after calling ww_acquire_done() ?
+ */
+ DEBUG_LOCKS_WARN_ON(ww_ctx->done_acquire);
+
+ if (ww_ctx->contending_lock) {
+ /*
+ * After -EDEADLK you tried to
+ * acquire a different ww_mutex? Bad!
+ */
+ DEBUG_LOCKS_WARN_ON(ww_ctx->contending_lock != ww);
- rt_mutex_init_waiter(&waiter);
+ /*
+ * You called ww_mutex_lock after receiving -EDEADLK,
+ * but 'forgot' to unlock everything else first?
+ */
+ DEBUG_LOCKS_WARN_ON(ww_ctx->acquired > 0);
+ ww_ctx->contending_lock = NULL;
+ }
/*
- * Technically we could use raw_spin_[un]lock_irq() here, but this can
- * be called in early boot if the cmpxchg() fast path is disabled
- * (debug, no architecture support). In this case we will acquire the
- * rtmutex with lock->wait_lock held. But we cannot unconditionally
- * enable interrupts in that early boot case. So we need to use the
- * irqsave/restore variants.
+ * Naughty, using a different class will lead to undefined behavior!
*/
- raw_spin_lock_irqsave(&lock->wait_lock, flags);
+ DEBUG_LOCKS_WARN_ON(ww_ctx->ww_class != ww->ww_class);
+#endif
+ ww_ctx->acquired++;
+}
+
+#ifdef CONFIG_PREEMPT_RT
+static void ww_mutex_account_lock(struct rt_mutex *lock,
+ struct ww_acquire_ctx *ww_ctx)
+{
+ struct ww_mutex *ww = container_of(lock, struct ww_mutex, base.lock);
+ struct rt_mutex_waiter *waiter, *n;
+
+ /*
+ * This branch gets optimized out for the common case,
+ * and is only important for ww_mutex_lock.
+ */
+ ww_mutex_lock_acquired(ww, ww_ctx);
+ ww->ctx = ww_ctx;
+
+ /*
+ * Give any possible sleeping processes the chance to wake up,
+ * so they can recheck if they have to back off.
+ */
+ rbtree_postorder_for_each_entry_safe(waiter, n, &lock->waiters.rb_root,
+ tree_entry) {
+ /* XXX debug rt mutex waiter wakeup */
+
+ BUG_ON(waiter->lock != lock);
+ rt_mutex_wake_waiter(waiter);
+ }
+}
+
+#else
+
+static void ww_mutex_account_lock(struct rt_mutex *lock,
+ struct ww_acquire_ctx *ww_ctx)
+{
+ BUG();
+}
+#endif
+
+int __sched rt_mutex_slowlock_locked(struct rt_mutex *lock, int state,
+ struct hrtimer_sleeper *timeout,
+ enum rtmutex_chainwalk chwalk,
+ struct ww_acquire_ctx *ww_ctx,
+ struct rt_mutex_waiter *waiter)
+{
+ int ret;
+
+#ifdef CONFIG_PREEMPT_RT
+ if (ww_ctx) {
+ struct ww_mutex *ww;
+
+ ww = container_of(lock, struct ww_mutex, base.lock);
+ if (unlikely(ww_ctx == READ_ONCE(ww->ctx)))
+ return -EALREADY;
+ }
+#endif
/* Try to acquire the lock again: */
if (try_to_take_rt_mutex(lock, current, NULL)) {
- raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+ if (ww_ctx)
+ ww_mutex_account_lock(lock, ww_ctx);
return 0;
}
@@ -1277,16 +1732,26 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
if (unlikely(timeout))
hrtimer_start_expires(&timeout->timer, HRTIMER_MODE_ABS);
- ret = task_blocks_on_rt_mutex(lock, &waiter, current, chwalk);
+ ret = task_blocks_on_rt_mutex(lock, waiter, current, chwalk);
- if (likely(!ret))
+ if (likely(!ret)) {
/* sleep on the mutex */
- ret = __rt_mutex_slowlock(lock, state, timeout, &waiter);
+ ret = __rt_mutex_slowlock(lock, state, timeout, waiter,
+ ww_ctx);
+ } else if (ww_ctx) {
+ /* ww_mutex received EDEADLK, let it become EALREADY */
+ ret = __mutex_lock_check_stamp(lock, ww_ctx);
+ BUG_ON(!ret);
+ }
if (unlikely(ret)) {
__set_current_state(TASK_RUNNING);
- remove_waiter(lock, &waiter);
- rt_mutex_handle_deadlock(ret, chwalk, lock, &waiter);
+ remove_waiter(lock, waiter);
+ /* ww_mutex wants to report EDEADLK/EALREADY, let it */
+ if (!ww_ctx)
+ rt_mutex_handle_deadlock(ret, chwalk, lock, waiter);
+ } else if (ww_ctx) {
+ ww_mutex_account_lock(lock, ww_ctx);
}
/*
@@ -1294,7 +1759,36 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
* unconditionally. We might have to fix that up.
*/
fixup_rt_mutex_waiters(lock, true);
+ return ret;
+}
+/*
+ * Slow path lock function:
+ */
+static int __sched
+rt_mutex_slowlock(struct rt_mutex *lock, int state,
+ struct hrtimer_sleeper *timeout,
+ enum rtmutex_chainwalk chwalk,
+ struct ww_acquire_ctx *ww_ctx)
+{
+ struct rt_mutex_waiter waiter;
+ unsigned long flags;
+ int ret = 0;
+
+ rt_mutex_init_waiter(&waiter, false);
+
+ /*
+ * Technically we could use raw_spin_[un]lock_irq() here, but this can
+ * be called in early boot if the cmpxchg() fast path is disabled
+ * (debug, no architecture support). In this case we will acquire the
+ * rtmutex with lock->wait_lock held. But we cannot unconditionally
+ * enable interrupts in that early boot case. So we need to use the
+ * irqsave/restore variants.
+ */
+ raw_spin_lock_irqsave(&lock->wait_lock, flags);
+
+ ret = rt_mutex_slowlock_locked(lock, state, timeout, chwalk, ww_ctx,
+ &waiter);
raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
/* Remove pending timer: */
@@ -1354,7 +1848,8 @@ static inline int rt_mutex_slowtrylock(struct rt_mutex *lock)
* Return whether the current task needs to call rt_mutex_postunlock().
*/
static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
- struct wake_q_head *wake_q)
+ struct wake_q_head *wake_q,
+ struct wake_q_head *wake_sleeper_q)
{
unsigned long flags;
@@ -1408,7 +1903,7 @@ static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
*
* Queue the next waiter for wakeup once we release the wait_lock.
*/
- mark_wakeup_next_waiter(wake_q, lock);
+ mark_wakeup_next_waiter(wake_q, wake_sleeper_q, lock);
raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
return true; /* call rt_mutex_postunlock() */
@@ -1422,29 +1917,16 @@ static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
*/
static inline int
rt_mutex_fastlock(struct rt_mutex *lock, int state,
+ struct ww_acquire_ctx *ww_ctx,
int (*slowfn)(struct rt_mutex *lock, int state,
struct hrtimer_sleeper *timeout,
- enum rtmutex_chainwalk chwalk))
+ enum rtmutex_chainwalk chwalk,
+ struct ww_acquire_ctx *ww_ctx))
{
if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
return 0;
- return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK);
-}
-
-static inline int
-rt_mutex_timed_fastlock(struct rt_mutex *lock, int state,
- struct hrtimer_sleeper *timeout,
- enum rtmutex_chainwalk chwalk,
- int (*slowfn)(struct rt_mutex *lock, int state,
- struct hrtimer_sleeper *timeout,
- enum rtmutex_chainwalk chwalk))
-{
- if (chwalk == RT_MUTEX_MIN_CHAINWALK &&
- likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
- return 0;
-
- return slowfn(lock, state, timeout, chwalk);
+ return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK, ww_ctx);
}
static inline int
@@ -1460,9 +1942,11 @@ rt_mutex_fasttrylock(struct rt_mutex *lock,
/*
* Performs the wakeup of the top-waiter and re-enables preemption.
*/
-void rt_mutex_postunlock(struct wake_q_head *wake_q)
+void rt_mutex_postunlock(struct wake_q_head *wake_q,
+ struct wake_q_head *wake_sleeper_q)
{
wake_up_q(wake_q);
+ wake_up_q_sleeper(wake_sleeper_q);
/* Pairs with preempt_disable() in rt_mutex_slowunlock() */
preempt_enable();
@@ -1471,23 +1955,46 @@ void rt_mutex_postunlock(struct wake_q_head *wake_q)
static inline void
rt_mutex_fastunlock(struct rt_mutex *lock,
bool (*slowfn)(struct rt_mutex *lock,
- struct wake_q_head *wqh))
+ struct wake_q_head *wqh,
+ struct wake_q_head *wq_sleeper))
{
DEFINE_WAKE_Q(wake_q);
+ DEFINE_WAKE_Q(wake_sleeper_q);
if (likely(rt_mutex_cmpxchg_release(lock, current, NULL)))
return;
- if (slowfn(lock, &wake_q))
- rt_mutex_postunlock(&wake_q);
+ if (slowfn(lock, &wake_q, &wake_sleeper_q))
+ rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
}
-static inline void __rt_mutex_lock(struct rt_mutex *lock, unsigned int subclass)
+int __sched __rt_mutex_lock_state(struct rt_mutex *lock, int state)
{
might_sleep();
+ return rt_mutex_fastlock(lock, state, NULL, rt_mutex_slowlock);
+}
+
+/**
+ * rt_mutex_lock_state - lock a rt_mutex with a given state
+ *
+ * @lock: The rt_mutex to be locked
+ * @state: The state to set when blocking on the rt_mutex
+ */
+static inline int __sched rt_mutex_lock_state(struct rt_mutex *lock,
+ unsigned int subclass, int state)
+{
+ int ret;
mutex_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
- rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, rt_mutex_slowlock);
+ ret = __rt_mutex_lock_state(lock, state);
+ if (ret)
+ mutex_release(&lock->dep_map, _RET_IP_);
+ return ret;
+}
+
+static inline void __rt_mutex_lock(struct rt_mutex *lock, unsigned int subclass)
+{
+ rt_mutex_lock_state(lock, subclass, TASK_UNINTERRUPTIBLE);
}
#ifdef CONFIG_DEBUG_LOCK_ALLOC
@@ -1528,16 +2035,7 @@ EXPORT_SYMBOL_GPL(rt_mutex_lock);
*/
int __sched rt_mutex_lock_interruptible(struct rt_mutex *lock)
{
- int ret;
-
- might_sleep();
-
- mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
- ret = rt_mutex_fastlock(lock, TASK_INTERRUPTIBLE, rt_mutex_slowlock);
- if (ret)
- mutex_release(&lock->dep_map, _RET_IP_);
-
- return ret;
+ return rt_mutex_lock_state(lock, 0, TASK_INTERRUPTIBLE);
}
EXPORT_SYMBOL_GPL(rt_mutex_lock_interruptible);
@@ -1554,36 +2052,17 @@ int __sched __rt_mutex_futex_trylock(struct rt_mutex *lock)
return __rt_mutex_slowtrylock(lock);
}
-/**
- * rt_mutex_timed_lock - lock a rt_mutex interruptible
- * the timeout structure is provided
- * by the caller
- *
- * @lock: the rt_mutex to be locked
- * @timeout: timeout structure or NULL (no timeout)
- *
- * Returns:
- * 0 on success
- * -EINTR when interrupted by a signal
- * -ETIMEDOUT when the timeout expired
- */
-int
-rt_mutex_timed_lock(struct rt_mutex *lock, struct hrtimer_sleeper *timeout)
+int __sched __rt_mutex_trylock(struct rt_mutex *lock)
{
- int ret;
-
- might_sleep();
-
- mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
- ret = rt_mutex_timed_fastlock(lock, TASK_INTERRUPTIBLE, timeout,
- RT_MUTEX_MIN_CHAINWALK,
- rt_mutex_slowlock);
- if (ret)
- mutex_release(&lock->dep_map, _RET_IP_);
+#ifdef CONFIG_PREEMPT_RT
+ if (WARN_ON_ONCE(in_irq() || in_nmi()))
+#else
+ if (WARN_ON_ONCE(in_irq() || in_nmi() || in_serving_softirq()))
+#endif
+ return 0;
- return ret;
+ return rt_mutex_fasttrylock(lock, rt_mutex_slowtrylock);
}
-EXPORT_SYMBOL_GPL(rt_mutex_timed_lock);
/**
* rt_mutex_trylock - try to lock a rt_mutex
@@ -1600,10 +2079,7 @@ int __sched rt_mutex_trylock(struct rt_mutex *lock)
{
int ret;
- if (WARN_ON_ONCE(in_irq() || in_nmi() || in_serving_softirq()))
- return 0;
-
- ret = rt_mutex_fasttrylock(lock, rt_mutex_slowtrylock);
+ ret = __rt_mutex_trylock(lock);
if (ret)
mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_);
@@ -1611,6 +2087,11 @@ int __sched rt_mutex_trylock(struct rt_mutex *lock)
}
EXPORT_SYMBOL_GPL(rt_mutex_trylock);
+void __sched __rt_mutex_unlock(struct rt_mutex *lock)
+{
+ rt_mutex_fastunlock(lock, rt_mutex_slowunlock);
+}
+
/**
* rt_mutex_unlock - unlock a rt_mutex
*
@@ -1619,16 +2100,13 @@ EXPORT_SYMBOL_GPL(rt_mutex_trylock);
void __sched rt_mutex_unlock(struct rt_mutex *lock)
{
mutex_release(&lock->dep_map, _RET_IP_);
- rt_mutex_fastunlock(lock, rt_mutex_slowunlock);
+ __rt_mutex_unlock(lock);
}
EXPORT_SYMBOL_GPL(rt_mutex_unlock);
-/**
- * Futex variant, that since futex variants do not use the fast-path, can be
- * simple and will not need to retry.
- */
-bool __sched __rt_mutex_futex_unlock(struct rt_mutex *lock,
- struct wake_q_head *wake_q)
+static bool __sched __rt_mutex_unlock_common(struct rt_mutex *lock,
+ struct wake_q_head *wake_q,
+ struct wake_q_head *wq_sleeper)
{
lockdep_assert_held(&lock->wait_lock);
@@ -1645,23 +2123,35 @@ bool __sched __rt_mutex_futex_unlock(struct rt_mutex *lock,
* avoid inversion prior to the wakeup. preempt_disable()
* therein pairs with rt_mutex_postunlock().
*/
- mark_wakeup_next_waiter(wake_q, lock);
+ mark_wakeup_next_waiter(wake_q, wq_sleeper, lock);
return true; /* call postunlock() */
}
+/**
+ * Futex variant, that since futex variants do not use the fast-path, can be
+ * simple and will not need to retry.
+ */
+bool __sched __rt_mutex_futex_unlock(struct rt_mutex *lock,
+ struct wake_q_head *wake_q,
+ struct wake_q_head *wq_sleeper)
+{
+ return __rt_mutex_unlock_common(lock, wake_q, wq_sleeper);
+}
+
void __sched rt_mutex_futex_unlock(struct rt_mutex *lock)
{
DEFINE_WAKE_Q(wake_q);
+ DEFINE_WAKE_Q(wake_sleeper_q);
unsigned long flags;
bool postunlock;
raw_spin_lock_irqsave(&lock->wait_lock, flags);
- postunlock = __rt_mutex_futex_unlock(lock, &wake_q);
+ postunlock = __rt_mutex_futex_unlock(lock, &wake_q, &wake_sleeper_q);
raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
if (postunlock)
- rt_mutex_postunlock(&wake_q);
+ rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
}
/**
@@ -1675,9 +2165,6 @@ void __sched rt_mutex_futex_unlock(struct rt_mutex *lock)
void rt_mutex_destroy(struct rt_mutex *lock)
{
WARN_ON(rt_mutex_is_locked(lock));
-#ifdef CONFIG_DEBUG_RT_MUTEXES
- lock->magic = NULL;
-#endif
}
EXPORT_SYMBOL_GPL(rt_mutex_destroy);
@@ -1700,7 +2187,7 @@ void __rt_mutex_init(struct rt_mutex *lock, const char *name,
if (name && key)
debug_rt_mutex_init(lock, name, key);
}
-EXPORT_SYMBOL_GPL(__rt_mutex_init);
+EXPORT_SYMBOL(__rt_mutex_init);
/**
* rt_mutex_init_proxy_locked - initialize and lock a rt_mutex on behalf of a
@@ -1720,6 +2207,14 @@ void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
struct task_struct *proxy_owner)
{
__rt_mutex_init(lock, NULL, NULL);
+#ifdef CONFIG_DEBUG_SPINLOCK
+ /*
+ * get another key class for the wait_lock. LOCK_PI and UNLOCK_PI is
+ * holding the ->wait_lock of the proxy_lock while unlocking a sleeping
+ * lock.
+ */
+ raw_spin_lock_init(&lock->wait_lock);
+#endif
debug_rt_mutex_proxy_lock(lock, proxy_owner);
rt_mutex_set_owner(lock, proxy_owner);
}
@@ -1742,6 +2237,26 @@ void rt_mutex_proxy_unlock(struct rt_mutex *lock)
rt_mutex_clear_owner(lock);
}
+static void fixup_rt_mutex_blocked(struct rt_mutex *lock)
+{
+ struct task_struct *tsk = current;
+ /*
+ * RT has a problem here when the wait got interrupted by a timeout
+ * or a signal. task->pi_blocked_on is still set. The task must
+ * acquire the hash bucket lock when returning from this function.
+ *
+ * If the hash bucket lock is contended then the
+ * BUG_ON(rt_mutex_real_waiter(task->pi_blocked_on)) in
+ * task_blocks_on_rt_mutex() will trigger. This can be avoided by
+ * clearing task->pi_blocked_on which removes the task from the
+ * boosting chain of the rtmutex. That's correct because the task
+ * is not longer blocked on it.
+ */
+ raw_spin_lock(&tsk->pi_lock);
+ tsk->pi_blocked_on = NULL;
+ raw_spin_unlock(&tsk->pi_lock);
+}
+
/**
* __rt_mutex_start_proxy_lock() - Start lock acquisition for another task
* @lock: the rt_mutex to take
@@ -1772,6 +2287,34 @@ int __rt_mutex_start_proxy_lock(struct rt_mutex *lock,
if (try_to_take_rt_mutex(lock, task, NULL))
return 1;
+#ifdef CONFIG_PREEMPT_RT
+ /*
+ * In PREEMPT_RT there's an added race.
+ * If the task, that we are about to requeue, times out,
+ * it can set the PI_WAKEUP_INPROGRESS. This tells the requeue
+ * to skip this task. But right after the task sets
+ * its pi_blocked_on to PI_WAKEUP_INPROGRESS it can then
+ * block on the spin_lock(&hb->lock), which in RT is an rtmutex.
+ * This will replace the PI_WAKEUP_INPROGRESS with the actual
+ * lock that it blocks on. We *must not* place this task
+ * on this proxy lock in that case.
+ *
+ * To prevent this race, we first take the task's pi_lock
+ * and check if it has updated its pi_blocked_on. If it has,
+ * we assume that it woke up and we return -EAGAIN.
+ * Otherwise, we set the task's pi_blocked_on to
+ * PI_REQUEUE_INPROGRESS, so that if the task is waking up
+ * it will know that we are in the process of requeuing it.
+ */
+ raw_spin_lock(&task->pi_lock);
+ if (task->pi_blocked_on) {
+ raw_spin_unlock(&task->pi_lock);
+ return -EAGAIN;
+ }
+ task->pi_blocked_on = PI_REQUEUE_INPROGRESS;
+ raw_spin_unlock(&task->pi_lock);
+#endif
+
/* We enforce deadlock detection for futexes */
ret = task_blocks_on_rt_mutex(lock, waiter, task,
RT_MUTEX_FULL_CHAINWALK);
@@ -1786,7 +2329,8 @@ int __rt_mutex_start_proxy_lock(struct rt_mutex *lock,
ret = 0;
}
- debug_rt_mutex_print_deadlock(waiter);
+ if (ret)
+ fixup_rt_mutex_blocked(lock);
return ret;
}
@@ -1871,7 +2415,7 @@ int rt_mutex_wait_proxy_lock(struct rt_mutex *lock,
raw_spin_lock_irq(&lock->wait_lock);
/* sleep on the mutex */
set_current_state(TASK_INTERRUPTIBLE);
- ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter);
+ ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter, NULL);
/*
* try_to_take_rt_mutex() sets the waiter bit unconditionally. We might
* have to fix that up.
@@ -1938,3 +2482,97 @@ bool rt_mutex_cleanup_proxy_lock(struct rt_mutex *lock,
return cleanup;
}
+
+static inline int
+ww_mutex_deadlock_injection(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+#ifdef CONFIG_DEBUG_WW_MUTEX_SLOWPATH
+ unsigned int tmp;
+
+ if (ctx->deadlock_inject_countdown-- == 0) {
+ tmp = ctx->deadlock_inject_interval;
+ if (tmp > UINT_MAX/4)
+ tmp = UINT_MAX;
+ else
+ tmp = tmp*2 + tmp + tmp/2;
+
+ ctx->deadlock_inject_interval = tmp;
+ ctx->deadlock_inject_countdown = tmp;
+ ctx->contending_lock = lock;
+
+ ww_mutex_unlock(lock);
+
+ return -EDEADLK;
+ }
+#endif
+
+ return 0;
+}
+
+#ifdef CONFIG_PREEMPT_RT
+int __sched
+ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+ int ret;
+
+ might_sleep();
+
+ mutex_acquire_nest(&lock->base.dep_map, 0, 0,
+ ctx ? &ctx->dep_map : NULL, _RET_IP_);
+ ret = rt_mutex_slowlock(&lock->base.lock, TASK_INTERRUPTIBLE, NULL, 0,
+ ctx);
+ if (ret)
+ mutex_release(&lock->base.dep_map, _RET_IP_);
+ else if (!ret && ctx && ctx->acquired > 1)
+ return ww_mutex_deadlock_injection(lock, ctx);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(ww_mutex_lock_interruptible);
+
+int __sched
+ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+ int ret;
+
+ might_sleep();
+
+ mutex_acquire_nest(&lock->base.dep_map, 0, 0,
+ ctx ? &ctx->dep_map : NULL, _RET_IP_);
+ ret = rt_mutex_slowlock(&lock->base.lock, TASK_UNINTERRUPTIBLE, NULL, 0,
+ ctx);
+ if (ret)
+ mutex_release(&lock->base.dep_map, _RET_IP_);
+ else if (!ret && ctx && ctx->acquired > 1)
+ return ww_mutex_deadlock_injection(lock, ctx);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(ww_mutex_lock);
+
+void __sched ww_mutex_unlock(struct ww_mutex *lock)
+{
+ /*
+ * The unlocking fastpath is the 0->1 transition from 'locked'
+ * into 'unlocked' state:
+ */
+ if (lock->ctx) {
+#ifdef CONFIG_DEBUG_MUTEXES
+ DEBUG_LOCKS_WARN_ON(!lock->ctx->acquired);
+#endif
+ if (lock->ctx->acquired > 0)
+ lock->ctx->acquired--;
+ lock->ctx = NULL;
+ }
+
+ mutex_release(&lock->base.dep_map, _RET_IP_);
+ __rt_mutex_unlock(&lock->base.lock);
+}
+EXPORT_SYMBOL(ww_mutex_unlock);
+
+int __rt_mutex_owner_current(struct rt_mutex *lock)
+{
+ return rt_mutex_owner(lock) == current;
+}
+EXPORT_SYMBOL(__rt_mutex_owner_current);
+#endif
diff --git a/kernel/locking/rtmutex.h b/kernel/locking/rtmutex.h
index 732f96abf..338ccd291 100644
--- a/kernel/locking/rtmutex.h
+++ b/kernel/locking/rtmutex.h
@@ -19,15 +19,8 @@
#define debug_rt_mutex_proxy_unlock(l) do { } while (0)
#define debug_rt_mutex_unlock(l) do { } while (0)
#define debug_rt_mutex_init(m, n, k) do { } while (0)
-#define debug_rt_mutex_deadlock(d, a ,l) do { } while (0)
-#define debug_rt_mutex_print_deadlock(w) do { } while (0)
#define debug_rt_mutex_reset_waiter(w) do { } while (0)
-static inline void rt_mutex_print_deadlock(struct rt_mutex_waiter *w)
-{
- WARN(1, "rtmutex deadlock detected\n");
-}
-
static inline bool debug_rt_mutex_detect_deadlock(struct rt_mutex_waiter *w,
enum rtmutex_chainwalk walk)
{
diff --git a/kernel/locking/rtmutex_common.h b/kernel/locking/rtmutex_common.h
index ca6fb4890..248a7d915 100644
--- a/kernel/locking/rtmutex_common.h
+++ b/kernel/locking/rtmutex_common.h
@@ -15,6 +15,7 @@
#include <linux/rtmutex.h>
#include <linux/sched/wake_q.h>
+#include <linux/sched/debug.h>
/*
* This is the control structure for tasks blocked on a rt_mutex,
@@ -29,12 +30,8 @@ struct rt_mutex_waiter {
struct rb_node pi_tree_entry;
struct task_struct *task;
struct rt_mutex *lock;
-#ifdef CONFIG_DEBUG_RT_MUTEXES
- unsigned long ip;
- struct pid *deadlock_task_pid;
- struct rt_mutex *deadlock_lock;
-#endif
int prio;
+ bool savestate;
u64 deadline;
};
@@ -130,11 +127,14 @@ enum rtmutex_chainwalk {
/*
* PI-futex support (proxy locking functions, etc.):
*/
+#define PI_WAKEUP_INPROGRESS ((struct rt_mutex_waiter *) 1)
+#define PI_REQUEUE_INPROGRESS ((struct rt_mutex_waiter *) 2)
+
extern struct task_struct *rt_mutex_next_owner(struct rt_mutex *lock);
extern void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
struct task_struct *proxy_owner);
extern void rt_mutex_proxy_unlock(struct rt_mutex *lock);
-extern void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter);
+extern void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter, bool savetate);
extern int __rt_mutex_start_proxy_lock(struct rt_mutex *lock,
struct rt_mutex_waiter *waiter,
struct task_struct *task);
@@ -152,9 +152,27 @@ extern int __rt_mutex_futex_trylock(struct rt_mutex *l);
extern void rt_mutex_futex_unlock(struct rt_mutex *lock);
extern bool __rt_mutex_futex_unlock(struct rt_mutex *lock,
- struct wake_q_head *wqh);
-
-extern void rt_mutex_postunlock(struct wake_q_head *wake_q);
+ struct wake_q_head *wqh,
+ struct wake_q_head *wq_sleeper);
+
+extern void rt_mutex_postunlock(struct wake_q_head *wake_q,
+ struct wake_q_head *wake_sleeper_q);
+
+/* RW semaphore special interface */
+struct ww_acquire_ctx;
+
+extern int __rt_mutex_lock_state(struct rt_mutex *lock, int state);
+extern int __rt_mutex_trylock(struct rt_mutex *lock);
+extern void __rt_mutex_unlock(struct rt_mutex *lock);
+int __sched rt_mutex_slowlock_locked(struct rt_mutex *lock, int state,
+ struct hrtimer_sleeper *timeout,
+ enum rtmutex_chainwalk chwalk,
+ struct ww_acquire_ctx *ww_ctx,
+ struct rt_mutex_waiter *waiter);
+void __sched rt_spin_lock_slowlock_locked(struct rt_mutex *lock,
+ struct rt_mutex_waiter *waiter,
+ unsigned long flags);
+void __sched rt_spin_lock_slowunlock(struct rt_mutex *lock);
#ifdef CONFIG_DEBUG_RT_MUTEXES
# include "rtmutex-debug.h"
diff --git a/kernel/locking/rwlock-rt.c b/kernel/locking/rwlock-rt.c
new file mode 100644
index 000000000..3d2d1f14b
--- /dev/null
+++ b/kernel/locking/rwlock-rt.c
@@ -0,0 +1,334 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/sched/debug.h>
+#include <linux/export.h>
+
+#include "rtmutex_common.h"
+#include <linux/rwlock_types_rt.h>
+
+/*
+ * RT-specific reader/writer locks
+ *
+ * write_lock()
+ * 1) Lock lock->rtmutex
+ * 2) Remove the reader BIAS to force readers into the slow path
+ * 3) Wait until all readers have left the critical region
+ * 4) Mark it write locked
+ *
+ * write_unlock()
+ * 1) Remove the write locked marker
+ * 2) Set the reader BIAS so readers can use the fast path again
+ * 3) Unlock lock->rtmutex to release blocked readers
+ *
+ * read_lock()
+ * 1) Try fast path acquisition (reader BIAS is set)
+ * 2) Take lock->rtmutex.wait_lock which protects the writelocked flag
+ * 3) If !writelocked, acquire it for read
+ * 4) If writelocked, block on lock->rtmutex
+ * 5) unlock lock->rtmutex, goto 1)
+ *
+ * read_unlock()
+ * 1) Try fast path release (reader count != 1)
+ * 2) Wake the writer waiting in write_lock()#3
+ *
+ * read_lock()#3 has the consequence, that rw locks on RT are not writer
+ * fair, but writers, which should be avoided in RT tasks (think tasklist
+ * lock), are subject to the rtmutex priority/DL inheritance mechanism.
+ *
+ * It's possible to make the rw locks writer fair by keeping a list of
+ * active readers. A blocked writer would force all newly incoming readers
+ * to block on the rtmutex, but the rtmutex would have to be proxy locked
+ * for one reader after the other. We can't use multi-reader inheritance
+ * because there is no way to support that with
+ * SCHED_DEADLINE. Implementing the one by one reader boosting/handover
+ * mechanism is a major surgery for a very dubious value.
+ *
+ * The risk of writer starvation is there, but the pathological use cases
+ * which trigger it are not necessarily the typical RT workloads.
+ */
+
+void __rwlock_biased_rt_init(struct rt_rw_lock *lock, const char *name,
+ struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ /*
+ * Make sure we are not reinitializing a held semaphore:
+ */
+ debug_check_no_locks_freed((void *)lock, sizeof(*lock));
+ lockdep_init_map(&lock->dep_map, name, key, 0);
+#endif
+ atomic_set(&lock->readers, READER_BIAS);
+ rt_mutex_init(&lock->rtmutex);
+ lock->rtmutex.save_state = 1;
+}
+
+static int __read_rt_trylock(struct rt_rw_lock *lock)
+{
+ int r, old;
+
+ /*
+ * Increment reader count, if lock->readers < 0, i.e. READER_BIAS is
+ * set.
+ */
+ for (r = atomic_read(&lock->readers); r < 0;) {
+ old = atomic_cmpxchg(&lock->readers, r, r + 1);
+ if (likely(old == r))
+ return 1;
+ r = old;
+ }
+ return 0;
+}
+
+static void __read_rt_lock(struct rt_rw_lock *lock)
+{
+ struct rt_mutex *m = &lock->rtmutex;
+ struct rt_mutex_waiter waiter;
+ unsigned long flags;
+
+ if (__read_rt_trylock(lock))
+ return;
+
+ raw_spin_lock_irqsave(&m->wait_lock, flags);
+ /*
+ * Allow readers as long as the writer has not completely
+ * acquired the semaphore for write.
+ */
+ if (atomic_read(&lock->readers) != WRITER_BIAS) {
+ atomic_inc(&lock->readers);
+ raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+ return;
+ }
+
+ /*
+ * Call into the slow lock path with the rtmutex->wait_lock
+ * held, so this can't result in the following race:
+ *
+ * Reader1 Reader2 Writer
+ * read_lock()
+ * write_lock()
+ * rtmutex_lock(m)
+ * swait()
+ * read_lock()
+ * unlock(m->wait_lock)
+ * read_unlock()
+ * swake()
+ * lock(m->wait_lock)
+ * lock->writelocked=true
+ * unlock(m->wait_lock)
+ *
+ * write_unlock()
+ * lock->writelocked=false
+ * rtmutex_unlock(m)
+ * read_lock()
+ * write_lock()
+ * rtmutex_lock(m)
+ * swait()
+ * rtmutex_lock(m)
+ *
+ * That would put Reader1 behind the writer waiting on
+ * Reader2 to call read_unlock() which might be unbound.
+ */
+ rt_mutex_init_waiter(&waiter, true);
+ rt_spin_lock_slowlock_locked(m, &waiter, flags);
+ /*
+ * The slowlock() above is guaranteed to return with the rtmutex is
+ * now held, so there can't be a writer active. Increment the reader
+ * count and immediately drop the rtmutex again.
+ */
+ atomic_inc(&lock->readers);
+ raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+ rt_spin_lock_slowunlock(m);
+
+ debug_rt_mutex_free_waiter(&waiter);
+}
+
+static void __read_rt_unlock(struct rt_rw_lock *lock)
+{
+ struct rt_mutex *m = &lock->rtmutex;
+ struct task_struct *tsk;
+
+ /*
+ * sem->readers can only hit 0 when a writer is waiting for the
+ * active readers to leave the critical region.
+ */
+ if (!atomic_dec_and_test(&lock->readers))
+ return;
+
+ raw_spin_lock_irq(&m->wait_lock);
+ /*
+ * Wake the writer, i.e. the rtmutex owner. It might release the
+ * rtmutex concurrently in the fast path, but to clean up the rw
+ * lock it needs to acquire m->wait_lock. The worst case which can
+ * happen is a spurious wakeup.
+ */
+ tsk = rt_mutex_owner(m);
+ if (tsk)
+ wake_up_process(tsk);
+
+ raw_spin_unlock_irq(&m->wait_lock);
+}
+
+static void __write_unlock_common(struct rt_rw_lock *lock, int bias,
+ unsigned long flags)
+{
+ struct rt_mutex *m = &lock->rtmutex;
+
+ atomic_add(READER_BIAS - bias, &lock->readers);
+ raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+ rt_spin_lock_slowunlock(m);
+}
+
+static void __write_rt_lock(struct rt_rw_lock *lock)
+{
+ struct rt_mutex *m = &lock->rtmutex;
+ struct task_struct *self = current;
+ unsigned long flags;
+
+ /* Take the rtmutex as a first step */
+ __rt_spin_lock(m);
+
+ /* Force readers into slow path */
+ atomic_sub(READER_BIAS, &lock->readers);
+
+ raw_spin_lock_irqsave(&m->wait_lock, flags);
+
+ raw_spin_lock(&self->pi_lock);
+ self->saved_state = self->state;
+ __set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+ raw_spin_unlock(&self->pi_lock);
+
+ for (;;) {
+ /* Have all readers left the critical region? */
+ if (!atomic_read(&lock->readers)) {
+ atomic_set(&lock->readers, WRITER_BIAS);
+ raw_spin_lock(&self->pi_lock);
+ __set_current_state_no_track(self->saved_state);
+ self->saved_state = TASK_RUNNING;
+ raw_spin_unlock(&self->pi_lock);
+ raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+ return;
+ }
+
+ raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+
+ if (atomic_read(&lock->readers) != 0)
+ preempt_schedule_lock();
+
+ raw_spin_lock_irqsave(&m->wait_lock, flags);
+
+ raw_spin_lock(&self->pi_lock);
+ __set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+ raw_spin_unlock(&self->pi_lock);
+ }
+}
+
+static int __write_rt_trylock(struct rt_rw_lock *lock)
+{
+ struct rt_mutex *m = &lock->rtmutex;
+ unsigned long flags;
+
+ if (!__rt_mutex_trylock(m))
+ return 0;
+
+ atomic_sub(READER_BIAS, &lock->readers);
+
+ raw_spin_lock_irqsave(&m->wait_lock, flags);
+ if (!atomic_read(&lock->readers)) {
+ atomic_set(&lock->readers, WRITER_BIAS);
+ raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+ return 1;
+ }
+ __write_unlock_common(lock, 0, flags);
+ return 0;
+}
+
+static void __write_rt_unlock(struct rt_rw_lock *lock)
+{
+ struct rt_mutex *m = &lock->rtmutex;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&m->wait_lock, flags);
+ __write_unlock_common(lock, WRITER_BIAS, flags);
+}
+
+int __lockfunc rt_read_can_lock(rwlock_t *rwlock)
+{
+ return atomic_read(&rwlock->readers) < 0;
+}
+
+int __lockfunc rt_write_can_lock(rwlock_t *rwlock)
+{
+ return atomic_read(&rwlock->readers) == READER_BIAS;
+}
+
+/*
+ * The common functions which get wrapped into the rwlock API.
+ */
+int __lockfunc rt_read_trylock(rwlock_t *rwlock)
+{
+ int ret;
+
+ ret = __read_rt_trylock(rwlock);
+ if (ret) {
+ rwlock_acquire_read(&rwlock->dep_map, 0, 1, _RET_IP_);
+ rcu_read_lock();
+ migrate_disable();
+ }
+ return ret;
+}
+EXPORT_SYMBOL(rt_read_trylock);
+
+int __lockfunc rt_write_trylock(rwlock_t *rwlock)
+{
+ int ret;
+
+ ret = __write_rt_trylock(rwlock);
+ if (ret) {
+ rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_);
+ rcu_read_lock();
+ migrate_disable();
+ }
+ return ret;
+}
+EXPORT_SYMBOL(rt_write_trylock);
+
+void __lockfunc rt_read_lock(rwlock_t *rwlock)
+{
+ rwlock_acquire_read(&rwlock->dep_map, 0, 0, _RET_IP_);
+ __read_rt_lock(rwlock);
+ rcu_read_lock();
+ migrate_disable();
+}
+EXPORT_SYMBOL(rt_read_lock);
+
+void __lockfunc rt_write_lock(rwlock_t *rwlock)
+{
+ rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_);
+ __write_rt_lock(rwlock);
+ rcu_read_lock();
+ migrate_disable();
+}
+EXPORT_SYMBOL(rt_write_lock);
+
+void __lockfunc rt_read_unlock(rwlock_t *rwlock)
+{
+ rwlock_release(&rwlock->dep_map, _RET_IP_);
+ migrate_enable();
+ rcu_read_unlock();
+ __read_rt_unlock(rwlock);
+}
+EXPORT_SYMBOL(rt_read_unlock);
+
+void __lockfunc rt_write_unlock(rwlock_t *rwlock)
+{
+ rwlock_release(&rwlock->dep_map, _RET_IP_);
+ migrate_enable();
+ rcu_read_unlock();
+ __write_rt_unlock(rwlock);
+}
+EXPORT_SYMBOL(rt_write_unlock);
+
+void __rt_rwlock_init(rwlock_t *rwlock, char *name, struct lock_class_key *key)
+{
+ __rwlock_biased_rt_init(rwlock, name, key);
+}
+EXPORT_SYMBOL(__rt_rwlock_init);
diff --git a/kernel/locking/rwsem-rt.c b/kernel/locking/rwsem-rt.c
new file mode 100644
index 000000000..b61edc4dc
--- /dev/null
+++ b/kernel/locking/rwsem-rt.c
@@ -0,0 +1,317 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/rwsem.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/signal.h>
+#include <linux/export.h>
+#include <linux/blkdev.h>
+
+#include "rtmutex_common.h"
+
+/*
+ * RT-specific reader/writer semaphores
+ *
+ * down_write()
+ * 1) Lock sem->rtmutex
+ * 2) Remove the reader BIAS to force readers into the slow path
+ * 3) Wait until all readers have left the critical region
+ * 4) Mark it write locked
+ *
+ * up_write()
+ * 1) Remove the write locked marker
+ * 2) Set the reader BIAS so readers can use the fast path again
+ * 3) Unlock sem->rtmutex to release blocked readers
+ *
+ * down_read()
+ * 1) Try fast path acquisition (reader BIAS is set)
+ * 2) Take sem->rtmutex.wait_lock which protects the writelocked flag
+ * 3) If !writelocked, acquire it for read
+ * 4) If writelocked, block on sem->rtmutex
+ * 5) unlock sem->rtmutex, goto 1)
+ *
+ * up_read()
+ * 1) Try fast path release (reader count != 1)
+ * 2) Wake the writer waiting in down_write()#3
+ *
+ * down_read()#3 has the consequence, that rw semaphores on RT are not writer
+ * fair, but writers, which should be avoided in RT tasks (think mmap_sem),
+ * are subject to the rtmutex priority/DL inheritance mechanism.
+ *
+ * It's possible to make the rw semaphores writer fair by keeping a list of
+ * active readers. A blocked writer would force all newly incoming readers to
+ * block on the rtmutex, but the rtmutex would have to be proxy locked for one
+ * reader after the other. We can't use multi-reader inheritance because there
+ * is no way to support that with SCHED_DEADLINE. Implementing the one by one
+ * reader boosting/handover mechanism is a major surgery for a very dubious
+ * value.
+ *
+ * The risk of writer starvation is there, but the pathological use cases
+ * which trigger it are not necessarily the typical RT workloads.
+ */
+
+void __rwsem_init(struct rw_semaphore *sem, const char *name,
+ struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ /*
+ * Make sure we are not reinitializing a held semaphore:
+ */
+ debug_check_no_locks_freed((void *)sem, sizeof(*sem));
+ lockdep_init_map(&sem->dep_map, name, key, 0);
+#endif
+ atomic_set(&sem->readers, READER_BIAS);
+}
+EXPORT_SYMBOL(__rwsem_init);
+
+int __down_read_trylock(struct rw_semaphore *sem)
+{
+ int r, old;
+
+ /*
+ * Increment reader count, if sem->readers < 0, i.e. READER_BIAS is
+ * set.
+ */
+ for (r = atomic_read(&sem->readers); r < 0;) {
+ old = atomic_cmpxchg(&sem->readers, r, r + 1);
+ if (likely(old == r))
+ return 1;
+ r = old;
+ }
+ return 0;
+}
+
+static int __sched __down_read_common(struct rw_semaphore *sem, int state)
+{
+ struct rt_mutex *m = &sem->rtmutex;
+ struct rt_mutex_waiter waiter;
+ int ret;
+
+ if (__down_read_trylock(sem))
+ return 0;
+
+ /*
+ * Flush blk before ->pi_blocked_on is set. At schedule() time it is too
+ * late if one of the callbacks needs to acquire a sleeping lock.
+ */
+ if (blk_needs_flush_plug(current))
+ blk_schedule_flush_plug(current);
+
+ might_sleep();
+ raw_spin_lock_irq(&m->wait_lock);
+ /*
+ * Allow readers as long as the writer has not completely
+ * acquired the semaphore for write.
+ */
+ if (atomic_read(&sem->readers) != WRITER_BIAS) {
+ atomic_inc(&sem->readers);
+ raw_spin_unlock_irq(&m->wait_lock);
+ return 0;
+ }
+
+ /*
+ * Call into the slow lock path with the rtmutex->wait_lock
+ * held, so this can't result in the following race:
+ *
+ * Reader1 Reader2 Writer
+ * down_read()
+ * down_write()
+ * rtmutex_lock(m)
+ * swait()
+ * down_read()
+ * unlock(m->wait_lock)
+ * up_read()
+ * swake()
+ * lock(m->wait_lock)
+ * sem->writelocked=true
+ * unlock(m->wait_lock)
+ *
+ * up_write()
+ * sem->writelocked=false
+ * rtmutex_unlock(m)
+ * down_read()
+ * down_write()
+ * rtmutex_lock(m)
+ * swait()
+ * rtmutex_lock(m)
+ *
+ * That would put Reader1 behind the writer waiting on
+ * Reader2 to call up_read() which might be unbound.
+ */
+ rt_mutex_init_waiter(&waiter, false);
+ ret = rt_mutex_slowlock_locked(m, state, NULL, RT_MUTEX_MIN_CHAINWALK,
+ NULL, &waiter);
+ /*
+ * The slowlock() above is guaranteed to return with the rtmutex (for
+ * ret = 0) is now held, so there can't be a writer active. Increment
+ * the reader count and immediately drop the rtmutex again.
+ * For ret != 0 we don't hold the rtmutex and need unlock the wait_lock.
+ * We don't own the lock then.
+ */
+ if (!ret)
+ atomic_inc(&sem->readers);
+ raw_spin_unlock_irq(&m->wait_lock);
+ if (!ret)
+ __rt_mutex_unlock(m);
+
+ debug_rt_mutex_free_waiter(&waiter);
+ return ret;
+}
+
+void __down_read(struct rw_semaphore *sem)
+{
+ int ret;
+
+ ret = __down_read_common(sem, TASK_UNINTERRUPTIBLE);
+ WARN_ON_ONCE(ret);
+}
+
+int __down_read_interruptible(struct rw_semaphore *sem)
+{
+ int ret;
+
+ ret = __down_read_common(sem, TASK_INTERRUPTIBLE);
+ if (likely(!ret))
+ return ret;
+ WARN_ONCE(ret != -EINTR, "Unexpected state: %d\n", ret);
+ return -EINTR;
+}
+
+int __down_read_killable(struct rw_semaphore *sem)
+{
+ int ret;
+
+ ret = __down_read_common(sem, TASK_KILLABLE);
+ if (likely(!ret))
+ return ret;
+ WARN_ONCE(ret != -EINTR, "Unexpected state: %d\n", ret);
+ return -EINTR;
+}
+
+void __up_read(struct rw_semaphore *sem)
+{
+ struct rt_mutex *m = &sem->rtmutex;
+ struct task_struct *tsk;
+
+ /*
+ * sem->readers can only hit 0 when a writer is waiting for the
+ * active readers to leave the critical region.
+ */
+ if (!atomic_dec_and_test(&sem->readers))
+ return;
+
+ raw_spin_lock_irq(&m->wait_lock);
+ /*
+ * Wake the writer, i.e. the rtmutex owner. It might release the
+ * rtmutex concurrently in the fast path (due to a signal), but to
+ * clean up the rwsem it needs to acquire m->wait_lock. The worst
+ * case which can happen is a spurious wakeup.
+ */
+ tsk = rt_mutex_owner(m);
+ if (tsk)
+ wake_up_process(tsk);
+
+ raw_spin_unlock_irq(&m->wait_lock);
+}
+
+static void __up_write_unlock(struct rw_semaphore *sem, int bias,
+ unsigned long flags)
+{
+ struct rt_mutex *m = &sem->rtmutex;
+
+ atomic_add(READER_BIAS - bias, &sem->readers);
+ raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+ __rt_mutex_unlock(m);
+}
+
+static int __sched __down_write_common(struct rw_semaphore *sem, int state)
+{
+ struct rt_mutex *m = &sem->rtmutex;
+ unsigned long flags;
+
+ /*
+ * Flush blk before ->pi_blocked_on is set. At schedule() time it is too
+ * late if one of the callbacks needs to acquire a sleeping lock.
+ */
+ if (blk_needs_flush_plug(current))
+ blk_schedule_flush_plug(current);
+
+ /* Take the rtmutex as a first step */
+ if (__rt_mutex_lock_state(m, state))
+ return -EINTR;
+
+ /* Force readers into slow path */
+ atomic_sub(READER_BIAS, &sem->readers);
+ might_sleep();
+
+ set_current_state(state);
+ for (;;) {
+ raw_spin_lock_irqsave(&m->wait_lock, flags);
+ /* Have all readers left the critical region? */
+ if (!atomic_read(&sem->readers)) {
+ atomic_set(&sem->readers, WRITER_BIAS);
+ __set_current_state(TASK_RUNNING);
+ raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+ return 0;
+ }
+
+ if (signal_pending_state(state, current)) {
+ __set_current_state(TASK_RUNNING);
+ __up_write_unlock(sem, 0, flags);
+ return -EINTR;
+ }
+ raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+
+ if (atomic_read(&sem->readers) != 0) {
+ schedule();
+ set_current_state(state);
+ }
+ }
+}
+
+void __sched __down_write(struct rw_semaphore *sem)
+{
+ __down_write_common(sem, TASK_UNINTERRUPTIBLE);
+}
+
+int __sched __down_write_killable(struct rw_semaphore *sem)
+{
+ return __down_write_common(sem, TASK_KILLABLE);
+}
+
+int __down_write_trylock(struct rw_semaphore *sem)
+{
+ struct rt_mutex *m = &sem->rtmutex;
+ unsigned long flags;
+
+ if (!__rt_mutex_trylock(m))
+ return 0;
+
+ atomic_sub(READER_BIAS, &sem->readers);
+
+ raw_spin_lock_irqsave(&m->wait_lock, flags);
+ if (!atomic_read(&sem->readers)) {
+ atomic_set(&sem->readers, WRITER_BIAS);
+ raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+ return 1;
+ }
+ __up_write_unlock(sem, 0, flags);
+ return 0;
+}
+
+void __up_write(struct rw_semaphore *sem)
+{
+ struct rt_mutex *m = &sem->rtmutex;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&m->wait_lock, flags);
+ __up_write_unlock(sem, WRITER_BIAS, flags);
+}
+
+void __downgrade_write(struct rw_semaphore *sem)
+{
+ struct rt_mutex *m = &sem->rtmutex;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&m->wait_lock, flags);
+ /* Release it and account current as reader */
+ __up_write_unlock(sem, WRITER_BIAS - 1, flags);
+}
diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c
index cc5cc889b..f7c909ef1 100644
--- a/kernel/locking/rwsem.c
+++ b/kernel/locking/rwsem.c
@@ -28,6 +28,7 @@
#include <linux/rwsem.h>
#include <linux/atomic.h>
+#ifndef CONFIG_PREEMPT_RT
#include "lock_events.h"
/*
@@ -1494,6 +1495,7 @@ static inline void __downgrade_write(struct rw_semaphore *sem)
if (tmp & RWSEM_FLAG_WAITERS)
rwsem_downgrade_wake(sem);
}
+#endif
/*
* lock for reading
@@ -1657,7 +1659,9 @@ void down_read_non_owner(struct rw_semaphore *sem)
{
might_sleep();
__down_read(sem);
+#ifndef CONFIG_PREEMPT_RT
__rwsem_set_reader_owned(sem, NULL);
+#endif
}
EXPORT_SYMBOL(down_read_non_owner);
@@ -1686,7 +1690,9 @@ EXPORT_SYMBOL(down_write_killable_nested);
void up_read_non_owner(struct rw_semaphore *sem)
{
+#ifndef CONFIG_PREEMPT_RT
DEBUG_RWSEMS_WARN_ON(!is_rwsem_reader_owned(sem), sem);
+#endif
__up_read(sem);
}
EXPORT_SYMBOL(up_read_non_owner);
diff --git a/kernel/locking/spinlock.c b/kernel/locking/spinlock.c
index 0ff08380f..45445a2f1 100644
--- a/kernel/locking/spinlock.c
+++ b/kernel/locking/spinlock.c
@@ -124,8 +124,11 @@ void __lockfunc __raw_##op##_lock_bh(locktype##_t *lock) \
* __[spin|read|write]_lock_bh()
*/
BUILD_LOCK_OPS(spin, raw_spinlock);
+
+#ifndef CONFIG_PREEMPT_RT
BUILD_LOCK_OPS(read, rwlock);
BUILD_LOCK_OPS(write, rwlock);
+#endif
#endif
@@ -209,6 +212,8 @@ void __lockfunc _raw_spin_unlock_bh(raw_spinlock_t *lock)
EXPORT_SYMBOL(_raw_spin_unlock_bh);
#endif
+#ifndef CONFIG_PREEMPT_RT
+
#ifndef CONFIG_INLINE_READ_TRYLOCK
int __lockfunc _raw_read_trylock(rwlock_t *lock)
{
@@ -353,6 +358,8 @@ void __lockfunc _raw_write_unlock_bh(rwlock_t *lock)
EXPORT_SYMBOL(_raw_write_unlock_bh);
#endif
+#endif /* !PREEMPT_RT */
+
#ifdef CONFIG_DEBUG_LOCK_ALLOC
void __lockfunc _raw_spin_lock_nested(raw_spinlock_t *lock, int subclass)
diff --git a/kernel/locking/spinlock_debug.c b/kernel/locking/spinlock_debug.c
index b9d93087e..72e306e0e 100644
--- a/kernel/locking/spinlock_debug.c
+++ b/kernel/locking/spinlock_debug.c
@@ -31,6 +31,7 @@ void __raw_spin_lock_init(raw_spinlock_t *lock, const char *name,
EXPORT_SYMBOL(__raw_spin_lock_init);
+#ifndef CONFIG_PREEMPT_RT
void __rwlock_init(rwlock_t *lock, const char *name,
struct lock_class_key *key)
{
@@ -48,6 +49,7 @@ void __rwlock_init(rwlock_t *lock, const char *name,
}
EXPORT_SYMBOL(__rwlock_init);
+#endif
static void spin_dump(raw_spinlock_t *lock, const char *msg)
{
@@ -139,6 +141,7 @@ void do_raw_spin_unlock(raw_spinlock_t *lock)
arch_spin_unlock(&lock->raw_lock);
}
+#ifndef CONFIG_PREEMPT_RT
static void rwlock_bug(rwlock_t *lock, const char *msg)
{
if (!debug_locks_off())
@@ -228,3 +231,5 @@ void do_raw_write_unlock(rwlock_t *lock)
debug_write_unlock(lock);
arch_write_unlock(&lock->raw_lock);
}
+
+#endif
diff --git a/kernel/notifier.c b/kernel/notifier.c
index 1b019cbca..c20782f07 100644
--- a/kernel/notifier.c
+++ b/kernel/notifier.c
@@ -142,9 +142,9 @@ int atomic_notifier_chain_register(struct atomic_notifier_head *nh,
unsigned long flags;
int ret;
- spin_lock_irqsave(&nh->lock, flags);
+ raw_spin_lock_irqsave(&nh->lock, flags);
ret = notifier_chain_register(&nh->head, n);
- spin_unlock_irqrestore(&nh->lock, flags);
+ raw_spin_unlock_irqrestore(&nh->lock, flags);
return ret;
}
EXPORT_SYMBOL_GPL(atomic_notifier_chain_register);
@@ -164,9 +164,9 @@ int atomic_notifier_chain_unregister(struct atomic_notifier_head *nh,
unsigned long flags;
int ret;
- spin_lock_irqsave(&nh->lock, flags);
+ raw_spin_lock_irqsave(&nh->lock, flags);
ret = notifier_chain_unregister(&nh->head, n);
- spin_unlock_irqrestore(&nh->lock, flags);
+ raw_spin_unlock_irqrestore(&nh->lock, flags);
synchronize_rcu();
return ret;
}
@@ -182,9 +182,9 @@ int atomic_notifier_call_chain_robust(struct atomic_notifier_head *nh,
* Musn't use RCU; because then the notifier list can
* change between the up and down traversal.
*/
- spin_lock_irqsave(&nh->lock, flags);
+ raw_spin_lock_irqsave(&nh->lock, flags);
ret = notifier_call_chain_robust(&nh->head, val_up, val_down, v);
- spin_unlock_irqrestore(&nh->lock, flags);
+ raw_spin_unlock_irqrestore(&nh->lock, flags);
return ret;
}
diff --git a/kernel/panic.c b/kernel/panic.c
index 6d7127667..abb1be02e 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -241,11 +241,26 @@ void check_panic_on_warn(const char *origin)
void panic(const char *fmt, ...)
{
static char buf[1024];
+ va_list args2;
va_list args;
long i, i_next = 0, len;
int state = 0;
int old_cpu, this_cpu;
bool _crash_kexec_post_notifiers = crash_kexec_post_notifiers;
+ console_verbose();
+ pr_emerg("Kernel panic - not syncing:\n");
+ va_start(args2, fmt);
+ va_copy(args, args2);
+ vprintk(fmt, args2);
+ va_end(args2);
+#ifdef CONFIG_DEBUG_BUGVERBOSE
+ /*
+ * Avoid nested stack-dumping if a panic occurs during oops processing
+ */
+ if (!test_taint(TAINT_DIE) && oops_in_progress <= 1)
+ dump_stack();
+#endif
+ pr_flush(1000, true);
if (panic_on_warn) {
/*
@@ -287,24 +302,13 @@ void panic(const char *fmt, ...)
if (old_cpu != PANIC_CPU_INVALID && old_cpu != this_cpu)
panic_smp_self_stop();
- console_verbose();
bust_spinlocks(1);
- va_start(args, fmt);
len = vscnprintf(buf, sizeof(buf), fmt, args);
va_end(args);
if (len && buf[len - 1] == '\n')
buf[len - 1] = '\0';
- pr_emerg("Kernel panic - not syncing: %s\n", buf);
-#ifdef CONFIG_DEBUG_BUGVERBOSE
- /*
- * Avoid nested stack-dumping if a panic occurs during oops processing
- */
- if (!test_taint(TAINT_DIE) && oops_in_progress <= 1)
- dump_stack();
-#endif
-
/*
* If kgdb is enabled, give it a chance to run before we stop all
* the other CPUs or else we won't be able to debug processes left
@@ -321,7 +325,6 @@ void panic(const char *fmt, ...)
* Bypass the panic_cpu check and call __crash_kexec directly.
*/
if (!_crash_kexec_post_notifiers) {
- printk_safe_flush_on_panic();
__crash_kexec(NULL);
/*
@@ -372,8 +375,6 @@ void panic(const char *fmt, ...)
*/
atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
- /* Call flush even twice. It tries harder with a single online CPU */
- printk_safe_flush_on_panic();
kmsg_dump(KMSG_DUMP_PANIC);
/*
@@ -651,9 +652,11 @@ static u64 oops_id;
static int init_oops_id(void)
{
+#ifndef CONFIG_PREEMPT_RT
if (!oops_id)
get_random_bytes(&oops_id, sizeof(oops_id));
else
+#endif
oops_id++;
return 0;
@@ -664,6 +667,7 @@ static void print_oops_end_marker(void)
{
init_oops_id();
pr_warn("---[ end trace %016llx ]---\n", (unsigned long long)oops_id);
+ pr_flush(1000, true);
}
/*
diff --git a/kernel/printk/Makefile b/kernel/printk/Makefile
index eee3dc9b6..59cb24e25 100644
--- a/kernel/printk/Makefile
+++ b/kernel/printk/Makefile
@@ -1,5 +1,4 @@
# SPDX-License-Identifier: GPL-2.0-only
obj-y = printk.o
-obj-$(CONFIG_PRINTK) += printk_safe.o
obj-$(CONFIG_A11Y_BRAILLE_CONSOLE) += braille.o
obj-$(CONFIG_PRINTK) += printk_ringbuffer.o
diff --git a/kernel/printk/internal.h b/kernel/printk/internal.h
index b1c155328..059c3d876 100644
--- a/kernel/printk/internal.h
+++ b/kernel/printk/internal.h
@@ -12,8 +12,6 @@
#define PRINTK_NMI_CONTEXT_OFFSET 0x010000000
-extern raw_spinlock_t logbuf_lock;
-
__printf(4, 0)
int vprintk_store(int facility, int level,
const struct dev_printk_info *dev_info,
@@ -23,7 +21,6 @@ __printf(1, 0) int vprintk_default(const char *fmt, va_list args);
__printf(1, 0) int vprintk_deferred(const char *fmt, va_list args);
__printf(1, 0) int vprintk_func(const char *fmt, va_list args);
-void printk_safe_init(void);
bool printk_percpu_data_ready(void);
void defer_console_output(void);
@@ -32,6 +29,5 @@ void defer_console_output(void);
__printf(1, 0) int vprintk_func(const char *fmt, va_list args) { return 0; }
-static inline void printk_safe_init(void) { }
static inline bool printk_percpu_data_ready(void) { return false; }
#endif /* CONFIG_PRINTK */
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index d6727b715..88a877fdc 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -44,6 +44,9 @@
#include <linux/irq_work.h>
#include <linux/ctype.h>
#include <linux/uio.h>
+#include <linux/kthread.h>
+#include <linux/kdb.h>
+#include <linux/clocksource.h>
#include <linux/sched/clock.h>
#include <linux/sched/debug.h>
#include <linux/sched/task_stack.h>
@@ -58,7 +61,6 @@
#include "printk_ringbuffer.h"
#include "console_cmdline.h"
#include "braille.h"
-#include "internal.h"
int console_printk[4] = {
CONSOLE_LOGLEVEL_DEFAULT, /* console_loglevel */
@@ -233,19 +235,7 @@ static int nr_ext_console_drivers;
static int __down_trylock_console_sem(unsigned long ip)
{
- int lock_failed;
- unsigned long flags;
-
- /*
- * Here and in __up_console_sem() we need to be in safe mode,
- * because spindump/WARN/etc from under console ->lock will
- * deadlock in printk()->down_trylock_console_sem() otherwise.
- */
- printk_safe_enter_irqsave(flags);
- lock_failed = down_trylock(&console_sem);
- printk_safe_exit_irqrestore(flags);
-
- if (lock_failed)
+ if (down_trylock(&console_sem))
return 1;
mutex_acquire(&console_lock_dep_map, 0, 1, ip);
return 0;
@@ -254,13 +244,9 @@ static int __down_trylock_console_sem(unsigned long ip)
static void __up_console_sem(unsigned long ip)
{
- unsigned long flags;
-
mutex_release(&console_lock_dep_map, ip);
- printk_safe_enter_irqsave(flags);
up(&console_sem);
- printk_safe_exit_irqrestore(flags);
}
#define up_console_sem() __up_console_sem(_RET_IP_)
@@ -279,11 +265,6 @@ static bool panic_in_progress(void)
*/
static int console_locked, console_suspended;
-/*
- * If exclusive_console is non-NULL then only this console is to be printed to.
- */
-static struct console *exclusive_console;
-
/*
* Array of consoles built from command line options (console=)
*/
@@ -368,61 +349,43 @@ enum log_flags {
LOG_CONT = 8, /* text is a fragment of a continuation line */
};
-/*
- * The logbuf_lock protects kmsg buffer, indices, counters. This can be taken
- * within the scheduler's rq lock. It must be released before calling
- * console_unlock() or anything else that might wake up a process.
- */
-DEFINE_RAW_SPINLOCK(logbuf_lock);
+#ifdef CONFIG_PRINTK
+/* syslog_lock protects syslog_* variables and write access to clear_seq. */
+static DEFINE_SPINLOCK(syslog_lock);
-/*
- * Helper macros to lock/unlock logbuf_lock and switch between
- * printk-safe/unsafe modes.
- */
-#define logbuf_lock_irq() \
- do { \
- printk_safe_enter_irq(); \
- raw_spin_lock(&logbuf_lock); \
- } while (0)
-
-#define logbuf_unlock_irq() \
- do { \
- raw_spin_unlock(&logbuf_lock); \
- printk_safe_exit_irq(); \
- } while (0)
-
-#define logbuf_lock_irqsave(flags) \
- do { \
- printk_safe_enter_irqsave(flags); \
- raw_spin_lock(&logbuf_lock); \
- } while (0)
-
-#define logbuf_unlock_irqrestore(flags) \
- do { \
- raw_spin_unlock(&logbuf_lock); \
- printk_safe_exit_irqrestore(flags); \
- } while (0)
+/* Set to enable sync mode. Once set, it is never cleared. */
+static bool sync_mode;
-#ifdef CONFIG_PRINTK
DECLARE_WAIT_QUEUE_HEAD(log_wait);
+/* All 3 protected by @syslog_lock. */
/* the next printk record to read by syslog(READ) or /proc/kmsg */
static u64 syslog_seq;
static size_t syslog_partial;
static bool syslog_time;
-/* the next printk record to write to the console */
-static u64 console_seq;
-static u64 exclusive_console_stop_seq;
-static unsigned long console_dropped;
+struct latched_seq {
+ seqcount_latch_t latch;
+ u64 val[2];
+};
-/* the next printk record to read after the last 'clear' command */
-static u64 clear_seq;
+/*
+ * The next printk record to read after the last 'clear' command. There are
+ * two copies (updated with seqcount_latch) so that reads can locklessly
+ * access a valid value. Writers are synchronized by @syslog_lock.
+ */
+static struct latched_seq clear_seq = {
+ .latch = SEQCNT_LATCH_ZERO(clear_seq.latch),
+ .val[0] = 0,
+ .val[1] = 0,
+};
#ifdef CONFIG_PRINTK_CALLER
#define PREFIX_MAX 48
#else
#define PREFIX_MAX 32
#endif
+
+/* the maximum size allowed to be reserved for a record */
#define LOG_LINE_MAX (1024 - PREFIX_MAX)
#define LOG_LEVEL(v) ((v) & 0x07)
@@ -460,11 +423,36 @@ static struct printk_ringbuffer *prb = &printk_rb_static;
*/
static bool __printk_percpu_data_ready __read_mostly;
-bool printk_percpu_data_ready(void)
+static bool printk_percpu_data_ready(void)
{
return __printk_percpu_data_ready;
}
+/* Must be called under syslog_lock. */
+static void latched_seq_write(struct latched_seq *ls, u64 val)
+{
+ raw_write_seqcount_latch(&ls->latch);
+ ls->val[0] = val;
+ raw_write_seqcount_latch(&ls->latch);
+ ls->val[1] = val;
+}
+
+/* Can be called from any context. */
+static u64 latched_seq_read_nolock(struct latched_seq *ls)
+{
+ unsigned int seq;
+ unsigned int idx;
+ u64 val;
+
+ do {
+ seq = raw_read_seqcount_latch(&ls->latch);
+ idx = seq & 0x1;
+ val = ls->val[idx];
+ } while (read_seqcount_latch_retry(&ls->latch, seq));
+
+ return val;
+}
+
/* Return log buffer address */
char *log_buf_addr_get(void)
{
@@ -506,52 +494,6 @@ static void truncate_msg(u16 *text_len, u16 *trunc_msg_len)
*trunc_msg_len = 0;
}
-/* insert record into the buffer, discard old ones, update heads */
-static int log_store(u32 caller_id, int facility, int level,
- enum log_flags flags, u64 ts_nsec,
- const struct dev_printk_info *dev_info,
- const char *text, u16 text_len)
-{
- struct prb_reserved_entry e;
- struct printk_record r;
- u16 trunc_msg_len = 0;
-
- prb_rec_init_wr(&r, text_len);
-
- if (!prb_reserve(&e, prb, &r)) {
- /* truncate the message if it is too long for empty buffer */
- truncate_msg(&text_len, &trunc_msg_len);
- prb_rec_init_wr(&r, text_len + trunc_msg_len);
- /* survive when the log buffer is too small for trunc_msg */
- if (!prb_reserve(&e, prb, &r))
- return 0;
- }
-
- /* fill message */
- memcpy(&r.text_buf[0], text, text_len);
- if (trunc_msg_len)
- memcpy(&r.text_buf[text_len], trunc_msg, trunc_msg_len);
- r.info->text_len = text_len + trunc_msg_len;
- r.info->facility = facility;
- r.info->level = level & 7;
- r.info->flags = flags & 0x1f;
- if (ts_nsec > 0)
- r.info->ts_nsec = ts_nsec;
- else
- r.info->ts_nsec = local_clock();
- r.info->caller_id = caller_id;
- if (dev_info)
- memcpy(&r.info->dev_info, dev_info, sizeof(r.info->dev_info));
-
- /* A message without a trailing newline can be continued. */
- if (!(flags & LOG_NEWLINE))
- prb_commit(&e);
- else
- prb_final_commit(&e);
-
- return (text_len + trunc_msg_len);
-}
-
int dmesg_restrict = IS_ENABLED(CONFIG_SECURITY_DMESG_RESTRICT);
static int syslog_action_restricted(int type)
@@ -680,7 +622,7 @@ out:
/* /dev/kmsg - userspace message inject/listen interface */
struct devkmsg_user {
- u64 seq;
+ atomic64_t seq;
struct ratelimit_state rs;
struct mutex lock;
char buf[CONSOLE_EXT_LOG_MAX];
@@ -781,27 +723,22 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf,
if (ret)
return ret;
- logbuf_lock_irq();
- if (!prb_read_valid(prb, user->seq, r)) {
+ if (!prb_read_valid(prb, atomic64_read(&user->seq), r)) {
if (file->f_flags & O_NONBLOCK) {
ret = -EAGAIN;
- logbuf_unlock_irq();
goto out;
}
- logbuf_unlock_irq();
ret = wait_event_interruptible(log_wait,
- prb_read_valid(prb, user->seq, r));
+ prb_read_valid(prb, atomic64_read(&user->seq), r));
if (ret)
goto out;
- logbuf_lock_irq();
}
- if (r->info->seq != user->seq) {
+ if (r->info->seq != atomic64_read(&user->seq)) {
/* our last seen message is gone, return error and reset */
- user->seq = r->info->seq;
+ atomic64_set(&user->seq, r->info->seq);
ret = -EPIPE;
- logbuf_unlock_irq();
goto out;
}
@@ -810,8 +747,7 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf,
&r->text_buf[0], r->info->text_len,
&r->info->dev_info);
- user->seq = r->info->seq + 1;
- logbuf_unlock_irq();
+ atomic64_set(&user->seq, r->info->seq + 1);
if (len > count) {
ret = -EINVAL;
@@ -846,11 +782,10 @@ static loff_t devkmsg_llseek(struct file *file, loff_t offset, int whence)
if (offset)
return -ESPIPE;
- logbuf_lock_irq();
switch (whence) {
case SEEK_SET:
/* the first record */
- user->seq = prb_first_valid_seq(prb);
+ atomic64_set(&user->seq, prb_first_valid_seq(prb));
break;
case SEEK_DATA:
/*
@@ -858,16 +793,15 @@ static loff_t devkmsg_llseek(struct file *file, loff_t offset, int whence)
* like issued by 'dmesg -c'. Reading /dev/kmsg itself
* changes no global state, and does not clear anything.
*/
- user->seq = clear_seq;
+ atomic64_set(&user->seq, latched_seq_read_nolock(&clear_seq));
break;
case SEEK_END:
/* after the last record */
- user->seq = prb_next_seq(prb);
+ atomic64_set(&user->seq, prb_next_seq(prb));
break;
default:
ret = -EINVAL;
}
- logbuf_unlock_irq();
return ret;
}
@@ -882,15 +816,13 @@ static __poll_t devkmsg_poll(struct file *file, poll_table *wait)
poll_wait(file, &log_wait, wait);
- logbuf_lock_irq();
- if (prb_read_valid_info(prb, user->seq, &info, NULL)) {
+ if (prb_read_valid_info(prb, atomic64_read(&user->seq), &info, NULL)) {
/* return error when data has vanished underneath us */
- if (info.seq != user->seq)
+ if (info.seq != atomic64_read(&user->seq))
ret = EPOLLIN|EPOLLRDNORM|EPOLLERR|EPOLLPRI;
else
ret = EPOLLIN|EPOLLRDNORM;
}
- logbuf_unlock_irq();
return ret;
}
@@ -923,9 +855,7 @@ static int devkmsg_open(struct inode *inode, struct file *file)
prb_rec_init_rd(&user->record, &user->info,
&user->text_buf[0], sizeof(user->text_buf));
- logbuf_lock_irq();
- user->seq = prb_first_valid_seq(prb);
- logbuf_unlock_irq();
+ atomic64_set(&user->seq, prb_first_valid_seq(prb));
file->private_data = user;
return 0;
@@ -1017,6 +947,9 @@ void log_buf_vmcoreinfo_setup(void)
VMCOREINFO_SIZE(atomic_long_t);
VMCOREINFO_TYPE_OFFSET(atomic_long_t, counter);
+
+ VMCOREINFO_STRUCT_SIZE(latched_seq);
+ VMCOREINFO_OFFSET(latched_seq, val);
}
#endif
@@ -1088,9 +1021,6 @@ static inline void log_buf_add_cpu(void) {}
static void __init set_percpu_data_ready(void)
{
- printk_safe_init();
- /* Make sure we set this flag only after printk_safe() init is done */
- barrier();
__printk_percpu_data_ready = true;
}
@@ -1130,7 +1060,6 @@ void __init setup_log_buf(int early)
struct printk_record r;
size_t new_descs_size;
size_t new_infos_size;
- unsigned long flags;
char *new_log_buf;
unsigned int free;
u64 seq;
@@ -1188,8 +1117,6 @@ void __init setup_log_buf(int early)
new_descs, ilog2(new_descs_count),
new_infos);
- logbuf_lock_irqsave(flags);
-
log_buf_len = new_log_buf_len;
log_buf = new_log_buf;
new_log_buf_len = 0;
@@ -1205,8 +1132,6 @@ void __init setup_log_buf(int early)
*/
prb = &printk_rb_dynamic;
- logbuf_unlock_irqrestore(flags);
-
if (seq != prb_next_seq(&printk_rb_static)) {
pr_err("dropped %llu messages\n",
prb_next_seq(&printk_rb_static) - seq);
@@ -1483,6 +1408,50 @@ static size_t get_record_print_text_size(struct printk_info *info,
return ((prefix_len * line_count) + info->text_len + 1);
}
+/*
+ * Beginning with @start_seq, find the first record where it and all following
+ * records up to (but not including) @max_seq fit into @size.
+ *
+ * @max_seq is simply an upper bound and does not need to exist. If the caller
+ * does not require an upper bound, -1 can be used for @max_seq.
+ */
+static u64 find_first_fitting_seq(u64 start_seq, u64 max_seq, size_t size,
+ bool syslog, bool time)
+{
+ struct printk_info info;
+ unsigned int line_count;
+ size_t len = 0;
+ u64 seq;
+
+ /* Determine the size of the records up to @max_seq. */
+ prb_for_each_info(start_seq, prb, seq, &info, &line_count) {
+ if (info.seq >= max_seq)
+ break;
+ len += get_record_print_text_size(&info, line_count, syslog, time);
+ }
+
+ /*
+ * Adjust the upper bound for the next loop to avoid subtracting
+ * lengths that were never added.
+ */
+ if (seq < max_seq)
+ max_seq = seq;
+
+ /*
+ * Move first record forward until length fits into the buffer. Ignore
+ * newest messages that were not counted in the above cycle. Messages
+ * might appear and get lost in the meantime. This is a best effort
+ * that prevents an infinite loop that could occur with a retry.
+ */
+ prb_for_each_info(start_seq, prb, seq, &info, &line_count) {
+ if (len <= size || info.seq >= max_seq)
+ break;
+ len -= get_record_print_text_size(&info, line_count, syslog, time);
+ }
+
+ return seq;
+}
+
static int syslog_print(char __user *buf, int size)
{
struct printk_info info;
@@ -1490,19 +1459,19 @@ static int syslog_print(char __user *buf, int size)
char *text;
int len = 0;
- text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
+ text = kmalloc(CONSOLE_LOG_MAX, GFP_KERNEL);
if (!text)
return -ENOMEM;
- prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);
+ prb_rec_init_rd(&r, &info, text, CONSOLE_LOG_MAX);
while (size > 0) {
size_t n;
size_t skip;
- logbuf_lock_irq();
+ spin_lock_irq(&syslog_lock);
if (!prb_read_valid(prb, syslog_seq, &r)) {
- logbuf_unlock_irq();
+ spin_unlock_irq(&syslog_lock);
break;
}
if (r.info->seq != syslog_seq) {
@@ -1531,7 +1500,7 @@ static int syslog_print(char __user *buf, int size)
syslog_partial += n;
} else
n = 0;
- logbuf_unlock_irq();
+ spin_unlock_irq(&syslog_lock);
if (!n)
break;
@@ -1554,34 +1523,25 @@ static int syslog_print(char __user *buf, int size)
static int syslog_print_all(char __user *buf, int size, bool clear)
{
struct printk_info info;
- unsigned int line_count;
struct printk_record r;
char *text;
int len = 0;
u64 seq;
bool time;
- text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
+ text = kmalloc(CONSOLE_LOG_MAX, GFP_KERNEL);
if (!text)
return -ENOMEM;
time = printk_time;
- logbuf_lock_irq();
/*
* Find first record that fits, including all following records,
* into the user-provided buffer for this dump.
*/
- prb_for_each_info(clear_seq, prb, seq, &info, &line_count)
- len += get_record_print_text_size(&info, line_count, true, time);
-
- /* move first record forward until length fits into the buffer */
- prb_for_each_info(clear_seq, prb, seq, &info, &line_count) {
- if (len <= size)
- break;
- len -= get_record_print_text_size(&info, line_count, true, time);
- }
+ seq = find_first_fitting_seq(latched_seq_read_nolock(&clear_seq), -1,
+ size, true, time);
- prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);
+ prb_rec_init_rd(&r, &info, text, CONSOLE_LOG_MAX);
len = 0;
prb_for_each_record(seq, prb, seq, &r) {
@@ -1594,20 +1554,20 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
break;
}
- logbuf_unlock_irq();
if (copy_to_user(buf + len, text, textlen))
len = -EFAULT;
else
len += textlen;
- logbuf_lock_irq();
if (len < 0)
break;
}
- if (clear)
- clear_seq = seq;
- logbuf_unlock_irq();
+ if (clear) {
+ spin_lock_irq(&syslog_lock);
+ latched_seq_write(&clear_seq, seq);
+ spin_unlock_irq(&syslog_lock);
+ }
kfree(text);
return len;
@@ -1615,9 +1575,21 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
static void syslog_clear(void)
{
- logbuf_lock_irq();
- clear_seq = prb_next_seq(prb);
- logbuf_unlock_irq();
+ spin_lock_irq(&syslog_lock);
+ latched_seq_write(&clear_seq, prb_next_seq(prb));
+ spin_unlock_irq(&syslog_lock);
+}
+
+/* Return a consistent copy of @syslog_seq. */
+static u64 read_syslog_seq_irq(void)
+{
+ u64 seq;
+
+ spin_lock_irq(&syslog_lock);
+ seq = syslog_seq;
+ spin_unlock_irq(&syslog_lock);
+
+ return seq;
}
int do_syslog(int type, char __user *buf, int len, int source)
@@ -1643,8 +1615,9 @@ int do_syslog(int type, char __user *buf, int len, int source)
return 0;
if (!access_ok(buf, len))
return -EFAULT;
+
error = wait_event_interruptible(log_wait,
- prb_read_valid(prb, syslog_seq, NULL));
+ prb_read_valid(prb, read_syslog_seq_irq(), NULL));
if (error)
return error;
error = syslog_print(buf, len);
@@ -1692,10 +1665,10 @@ int do_syslog(int type, char __user *buf, int len, int source)
break;
/* Number of chars in the log buffer */
case SYSLOG_ACTION_SIZE_UNREAD:
- logbuf_lock_irq();
+ spin_lock_irq(&syslog_lock);
if (!prb_read_valid_info(prb, syslog_seq, &info, NULL)) {
/* No unread messages. */
- logbuf_unlock_irq();
+ spin_unlock_irq(&syslog_lock);
return 0;
}
if (info.seq != syslog_seq) {
@@ -1723,7 +1696,7 @@ int do_syslog(int type, char __user *buf, int len, int source)
}
error -= syslog_partial;
}
- logbuf_unlock_irq();
+ spin_unlock_irq(&syslog_lock);
break;
/* Size of the log buffer */
case SYSLOG_ACTION_SIZE_BUFFER:
@@ -1742,169 +1715,308 @@ SYSCALL_DEFINE3(syslog, int, type, char __user *, buf, int, len)
return do_syslog(type, buf, len, SYSLOG_FROM_READER);
}
-/*
- * Special console_lock variants that help to reduce the risk of soft-lockups.
- * They allow to pass console_lock to another printk() call using a busy wait.
- */
+int printk_delay_msec __read_mostly;
+
+static inline void printk_delay(int level)
+{
+ boot_delay_msec(level);
-#ifdef CONFIG_LOCKDEP
-static struct lockdep_map console_owner_dep_map = {
- .name = "console_owner"
-};
-#endif
+ if (unlikely(printk_delay_msec)) {
+ int m = printk_delay_msec;
+
+ while (m--) {
+ mdelay(1);
+ touch_nmi_watchdog();
+ }
+ }
+}
+
+static bool kernel_sync_mode(void)
+ {
+ return (oops_in_progress || sync_mode);
+}
+
+static bool console_can_sync(struct console *con)
+{
+ if (!(con->flags & CON_ENABLED))
+ return false;
+ if (con->write_atomic && kernel_sync_mode())
+ return true;
+ if (con->write_atomic && (con->flags & CON_HANDOVER) && !con->thread)
+ return true;
+ if (con->write && (con->flags & CON_BOOT) && !con->thread)
+ return true;
+ return false;
+}
+
+static bool call_sync_console_driver(struct console *con, const char *text, size_t text_len)
+{
+ if (!(con->flags & CON_ENABLED))
+ return false;
+ if (con->write_atomic && kernel_sync_mode())
+ con->write_atomic(con, text, text_len);
+ else if (con->write_atomic && (con->flags & CON_HANDOVER) && !con->thread)
+ con->write_atomic(con, text, text_len);
+ else if (con->write && (con->flags & CON_BOOT) && !con->thread)
+ con->write(con, text, text_len);
+ else
+ return false;
+
+ return true;
+ }
-static DEFINE_RAW_SPINLOCK(console_owner_lock);
-static struct task_struct *console_owner;
-static bool console_waiter;
+static bool have_atomic_console(void)
+ {
+
+ struct console *con;
+
+ for_each_console(con) {
+ if (!(con->flags & CON_ENABLED))
+ continue;
+ if (con->write_atomic)
+ return true;
+ }
+ return false;
+ }
+
+static bool print_sync(struct console *con, u64 *seq)
+ {
+ struct printk_info info;
+ struct printk_record r;
+ size_t text_len;
+
+ prb_rec_init_rd(&r, &info, &con->sync_buf[0], sizeof(con->sync_buf));
+
+ if (!prb_read_valid(prb, *seq, &r))
+ return false;
+
+ text_len = record_print_text(&r, console_msg_format & MSG_FORMAT_SYSLOG, printk_time);
+
+ if (!call_sync_console_driver(con, &con->sync_buf[0], text_len))
+ return false;
+
+ *seq = r.info->seq;
+
+ touch_softlockup_watchdog_sync();
+ clocksource_touch_watchdog();
+ rcu_cpu_stall_reset();
+ touch_nmi_watchdog();
+
+ if (text_len)
+ printk_delay(r.info->level);
+
+ return true;
+}
+
+static void print_sync_until(struct console *con, u64 seq)
+{
+ unsigned int flags;
+ u64 printk_seq;
+
+ console_atomic_lock(&flags);
+ for (;;) {
+ printk_seq = atomic64_read(&con->printk_seq);
+ if (printk_seq >= seq)
+ break;
+ if (!print_sync(con, &printk_seq))
+ break;
+ atomic64_set(&con->printk_seq, printk_seq + 1);
+ }
+ console_atomic_unlock(flags);
+}
+
#if defined(CONFIG_X86) || defined(CONFIG_ARM64_PSEUDO_NMI)
void zap_locks(void)
{
- if (raw_spin_is_locked(&logbuf_lock)) {
- debug_locks_off();
- raw_spin_lock_init(&logbuf_lock);
- }
-
- if (raw_spin_is_locked(&console_owner_lock)) {
- raw_spin_lock_init(&console_owner_lock);
- }
+// if (raw_spin_is_locked(&logbuf_lock)) {
+// debug_locks_off();
+// raw_spin_lock_init(&logbuf_lock);
+// }
+
+// if (raw_spin_is_locked(&console_owner_lock)) {
+// raw_spin_lock_init(&console_owner_lock);
+// }
+
+// console_owner = NULL;
+// console_waiter = false;
+
+// sema_init(&console_sem, 1);
+ }
+#endif
+
+#ifdef CONFIG_PRINTK_NMI
+#define NUM_RECURSION_CTX 2
+#else
+#define NUM_RECURSION_CTX 1
+#endif
+
+struct printk_recursion {
+ char count[NUM_RECURSION_CTX];
+};
+
+static DEFINE_PER_CPU(struct printk_recursion, percpu_printk_recursion);
+static char printk_recursion_count[NUM_RECURSION_CTX];
+
+static char *printk_recursion_counter(void)
+{
+ struct printk_recursion *rec;
+ char *count;
+
+ if (!printk_percpu_data_ready()) {
+ count = &printk_recursion_count[0];
+ } else {
+ rec = this_cpu_ptr(&percpu_printk_recursion);
+ count = &rec->count[0];
+ }
- console_owner = NULL;
- console_waiter = false;
+#ifdef CONFIG_PRINTK_NMI
+ if (in_nmi())
+ count++;
+#endif
- sema_init(&console_sem, 1);
+ return count;
}
-#endif
+
+static bool printk_enter_irqsave(unsigned long *flags)
+ {
-/**
- * console_lock_spinning_enable - mark beginning of code where another
- * thread might safely busy wait
- *
- * This basically converts console_lock into a spinlock. This marks
- * the section where the console_lock owner can not sleep, because
- * there may be a waiter spinning (like a spinlock). Also it must be
- * ready to hand over the lock at the end of the section.
- */
-static void console_lock_spinning_enable(void)
-{
- raw_spin_lock(&console_owner_lock);
- console_owner = current;
- raw_spin_unlock(&console_owner_lock);
+ char *count;
+
+ local_irq_save(*flags);
+ count = printk_recursion_counter();
+ /* Only 1 level of recursion allowed. */
+ if (*count > 1) {
+ local_irq_restore(*flags);
+ return false;
+ }
+ (*count)++;
- /* The waiter may spin on us after setting console_owner */
- spin_acquire(&console_owner_dep_map, 0, 0, _THIS_IP_);
+ return true;
}
-/**
- * console_lock_spinning_disable_and_check - mark end of code where another
- * thread was able to busy wait and check if there is a waiter
- *
- * This is called at the end of the section where spinning is allowed.
- * It has two functions. First, it is a signal that it is no longer
- * safe to start busy waiting for the lock. Second, it checks if
- * there is a busy waiter and passes the lock rights to her.
- *
- * Important: Callers lose the lock if there was a busy waiter.
- * They must not touch items synchronized by console_lock
- * in this case.
- *
- * Return: 1 if the lock rights were passed, 0 otherwise.
- */
-static int console_lock_spinning_disable_and_check(void)
+static void printk_exit_irqrestore(unsigned long flags)
{
- int waiter;
-
- raw_spin_lock(&console_owner_lock);
- waiter = READ_ONCE(console_waiter);
- console_owner = NULL;
- raw_spin_unlock(&console_owner_lock);
-
- if (!waiter) {
- spin_release(&console_owner_dep_map, _THIS_IP_);
- return 0;
- }
+ char *count;
- /* The waiter is now free to continue */
- WRITE_ONCE(console_waiter, false);
+ count = printk_recursion_counter();
+ (*count)--;
+ local_irq_restore(flags);
+ }
- spin_release(&console_owner_dep_map, _THIS_IP_);
-
- /*
- * Hand off console_lock to waiter. The waiter will perform
- * the up(). After this, the waiter is the console_lock owner.
- */
- mutex_release(&console_lock_dep_map, _THIS_IP_);
- return 1;
+static inline u32 printk_caller_id(void)
+{
+ return in_task() ? task_pid_nr(current) :
+ 0x80000000 + raw_smp_processor_id();
}
/**
- * console_trylock_spinning - try to get console_lock by busy waiting
- *
- * This allows to busy wait for the console_lock when the current
- * owner is running in specially marked sections. It means that
- * the current owner is running and cannot reschedule until it
- * is ready to lose the lock.
- *
- * Return: 1 if we got the lock, 0 othrewise
+ * parse_prefix - Parse level and control flags.
+ *
+ * @text: The terminated text message.
+ * @level: A pointer to the current level value, will be updated.
+ * @lflags: A pointer to the current log flags, will be updated.
+ *
+ * @level may be NULL if the caller is not interested in the parsed value.
+ * Otherwise the variable pointed to by @level must be set to
+ * LOGLEVEL_DEFAULT in order to be updated with the parsed value.
+ *
+ * @lflags may be NULL if the caller is not interested in the parsed value.
+ * Otherwise the variable pointed to by @lflags will be OR'd with the parsed
+ * value.
+ *
+ * Return: The length of the parsed level and control flags.
*/
-static int console_trylock_spinning(void)
+static u16 parse_prefix(char *text, int *level, enum log_flags *lflags)
+ {
+ u16 prefix_len = 0;
+ int kern_level;
+
+ while (*text) {
+ kern_level = printk_get_level(text);
+ if (!kern_level)
+ break;
+
+ switch (kern_level) {
+ case '0' ... '7':
+ if (level && *level == LOGLEVEL_DEFAULT)
+ *level = kern_level - '0';
+ break;
+ case 'c': /* KERN_CONT */
+ if (lflags)
+ *lflags |= LOG_CONT;
+ }
+
+ prefix_len += 2;
+ text += 2;
+ }
+
+ return prefix_len;
+ }
+
+static u16 printk_sprint(char *text, u16 size, int facility, enum log_flags *lflags,
+ const char *fmt, va_list args)
+ {
+ u16 text_len;
+
+ text_len = vscnprintf(text, size, fmt, args);
+
+ /* Mark and strip a trailing newline. */
+ if (text_len && text[text_len - 1] == '\n') {
+ text_len--;
+ *lflags |= LOG_NEWLINE;
+ }
+
+ /* Strip log level and control flags. */
+ if (facility == 0) {
+ u16 prefix_len;
+
+ prefix_len = parse_prefix(text, NULL, NULL);
+ if (prefix_len) {
+ text_len -= prefix_len;
+ memmove(text, text + prefix_len, text_len);
+ }
+ }
+
+ return text_len;
+ }
+
+__printf(4, 0)
+static int vprintk_store(int facility, int level,
+ const struct dev_printk_info *dev_info,
+ const char *fmt, va_list args)
{
- struct task_struct *owner = NULL;
- bool waiter;
- bool spin = false;
- unsigned long flags;
-
- if (console_trylock())
- return 1;
+ const u32 caller_id = printk_caller_id();
+ struct prb_reserved_entry e;
+ enum log_flags lflags = 0;
+ bool final_commit = false;
+ struct printk_record r;
+ unsigned long irqflags;
+ u16 trunc_msg_len = 0;
+ char prefix_buf[8];
+ u16 reserve_size;
+ va_list args2;
+ u16 text_len;
+ int ret = 0;
+ u64 ts_nsec;
+ u64 seq;
/*
- * It's unsafe to spin once a panic has begun. If we are the
- * panic CPU, we may have already halted the owner of the
- * console_sem. If we are not the panic CPU, then we should
- * avoid taking console_sem, so the panic CPU has a better
- * chance of cleanly acquiring it later.
+ * Since the duration of printk() can vary depending on the message
+ * and state of the ringbuffer, grab the timestamp now so that it is
+ * close to the call of printk(). This provides a more deterministic
+ * timestamp with respect to the caller.
*/
- if (panic_in_progress())
- return 0;
-
- printk_safe_enter_irqsave(flags);
+ ts_nsec = local_clock();
- raw_spin_lock(&console_owner_lock);
- owner = READ_ONCE(console_owner);
- waiter = READ_ONCE(console_waiter);
- if (!waiter && owner && owner != current) {
- WRITE_ONCE(console_waiter, true);
- spin = true;
- }
- raw_spin_unlock(&console_owner_lock);
-
- /*
- * If there is an active printk() writing to the
- * consoles, instead of having it write our data too,
- * see if we can offload that load from the active
- * printer, and do some printing ourselves.
- * Go into a spin only if there isn't already a waiter
- * spinning, and there is an active printer, and
- * that active printer isn't us (recursive printk?).
- */
- if (!spin) {
- printk_safe_exit_irqrestore(flags);
+ if (!printk_enter_irqsave(&irqflags))
return 0;
- }
-
- /* We spin waiting for the owner to release us */
- spin_acquire(&console_owner_dep_map, 0, 0, _THIS_IP_);
- /* Owner will clear console_waiter on hand off */
- while (READ_ONCE(console_waiter))
- cpu_relax();
- spin_release(&console_owner_dep_map, _THIS_IP_);
- printk_safe_exit_irqrestore(flags);
/*
- * The owner passed the console lock to us.
- * Since we did not spin on console lock, annotate
- * this as a trylock. Otherwise lockdep will
- * complain.
+ * The sprintf needs to come first since the syslog prefix might be
+ * passed in as a parameter. An extra byte must be reserved so that
+ * later the vscnprintf() into the reserved buffer has room for the
+ * terminating '\0', which is not counted by vsnprintf().
*/
mutex_acquire(&console_lock_dep_map, 0, 1, _THIS_IP_);
@@ -1912,205 +2024,134 @@ static int console_trylock_spinning(void)
* Update @console_may_schedule for trylock because the previous
* owner may have been schedulable.
*/
- console_may_schedule = 0;
-
- return 1;
-}
-
-/*
- * Call the console drivers, asking them to write out
- * log_buf[start] to log_buf[end - 1].
- * The console_lock must be held.
- */
-static void call_console_drivers(const char *ext_text, size_t ext_len,
- const char *text, size_t len)
-{
- static char dropped_text[64];
- size_t dropped_len = 0;
- struct console *con;
-
- trace_console_rcuidle(text, len);
-
- if (!console_drivers)
- return;
-
- if (console_dropped) {
- dropped_len = snprintf(dropped_text, sizeof(dropped_text),
- "** %lu printk messages dropped **\n",
- console_dropped);
- console_dropped = 0;
- }
-
- for_each_console(con) {
- if (exclusive_console && con != exclusive_console)
- continue;
- if (!(con->flags & CON_ENABLED))
- continue;
- if (!con->write)
- continue;
- if (!cpu_online(smp_processor_id()) &&
- !(con->flags & CON_ANYTIME))
- continue;
- if (con->flags & CON_EXTENDED)
- con->write(con, ext_text, ext_len);
- else {
- if (dropped_len)
- con->write(con, dropped_text, dropped_len);
- con->write(con, text, len);
- }
- }
-}
-
-int printk_delay_msec __read_mostly;
+ va_copy(args2, args);
+ reserve_size = vsnprintf(&prefix_buf[0], sizeof(prefix_buf), fmt, args2) + 1;
+ va_end(args2);
-static inline void printk_delay(void)
-{
- if (unlikely(printk_delay_msec)) {
- int m = printk_delay_msec;
+ if (reserve_size > LOG_LINE_MAX)
+ reserve_size = LOG_LINE_MAX;
- while (m--) {
- mdelay(1);
- touch_nmi_watchdog();
- }
- }
-}
+ /* Extract log level or control flags. */
+ if (facility == 0)
+ parse_prefix(&prefix_buf[0], &level, &lflags);
-static inline u32 printk_caller_id(void)
-{
- return in_task() ? task_pid_nr(current) :
- 0x80000000 + raw_smp_processor_id();
-}
+ if (level == LOGLEVEL_DEFAULT)
+ level = default_message_loglevel;
-static size_t log_output(int facility, int level, enum log_flags lflags,
- const struct dev_printk_info *dev_info,
- char *text, size_t text_len)
-{
- const u32 caller_id = printk_caller_id();
+ if (dev_info)
+ lflags |= LOG_NEWLINE;
if (lflags & LOG_CONT) {
- struct prb_reserved_entry e;
- struct printk_record r;
-
- prb_rec_init_wr(&r, text_len);
+ prb_rec_init_wr(&r, reserve_size);
if (prb_reserve_in_last(&e, prb, &r, caller_id, LOG_LINE_MAX)) {
- memcpy(&r.text_buf[r.info->text_len], text, text_len);
+ seq = r.info->seq;
+ text_len = printk_sprint(&r.text_buf[r.info->text_len], reserve_size,
+ facility, &lflags, fmt, args);
r.info->text_len += text_len;
if (lflags & LOG_NEWLINE) {
r.info->flags |= LOG_NEWLINE;
prb_final_commit(&e);
+ final_commit = true;
} else {
prb_commit(&e);
}
- return text_len;
+
+ ret = text_len;
+ goto out;
}
}
- /* Store it in the record log */
- return log_store(caller_id, facility, level, lflags, 0,
- dev_info, text, text_len);
-}
-
-/* Must be called under logbuf_lock. */
-int vprintk_store(int facility, int level,
- const struct dev_printk_info *dev_info,
- const char *fmt, va_list args)
-{
- static char textbuf[LOG_LINE_MAX];
- char *text = textbuf;
- size_t text_len;
- enum log_flags lflags = 0;
/*
- * The printf needs to come first; we need the syslog
- * prefix which might be passed-in as a parameter.
+ * Explicitly initialize the record before every prb_reserve() call.
+ * prb_reserve_in_last() and prb_reserve() purposely invalidate the
+ * structure when they fail.
*/
- text_len = vscnprintf(text, sizeof(textbuf), fmt, args);
+ prb_rec_init_wr(&r, reserve_size);
+ if (!prb_reserve(&e, prb, &r)) {
+ /* truncate the message if it is too long for empty buffer */
+ truncate_msg(&reserve_size, &trunc_msg_len);
- /* mark and strip a trailing newline */
- if (text_len && text[text_len-1] == '\n') {
- text_len--;
- lflags |= LOG_NEWLINE;
- }
-
- /* strip kernel syslog prefix and extract log level or control flags */
- if (facility == 0) {
- int kern_level;
-
- while ((kern_level = printk_get_level(text)) != 0) {
- switch (kern_level) {
- case '0' ... '7':
- if (level == LOGLEVEL_DEFAULT)
- level = kern_level - '0';
- break;
- case 'c': /* KERN_CONT */
- lflags |= LOG_CONT;
- }
-
- text_len -= 2;
- text += 2;
- }
+ prb_rec_init_wr(&r, reserve_size + trunc_msg_len);
+ if (!prb_reserve(&e, prb, &r))
+ goto out;
}
- if (level == LOGLEVEL_DEFAULT)
- level = default_message_loglevel;
+ seq = r.info->seq;
+
+ /* fill message */
+ text_len = printk_sprint(&r.text_buf[0], reserve_size, facility, &lflags, fmt, args);
+ if (trunc_msg_len)
+ memcpy(&r.text_buf[text_len], trunc_msg, trunc_msg_len);
+ r.info->text_len = text_len + trunc_msg_len;
+ r.info->facility = facility;
+ r.info->level = level & 7;
+ r.info->flags = lflags & 0x1f;
+ r.info->ts_nsec = ts_nsec;
+ r.info->caller_id = caller_id;
if (dev_info)
- lflags |= LOG_NEWLINE;
-
- return log_output(facility, level, lflags, dev_info, text, text_len);
-}
-
-asmlinkage int vprintk_emit(int facility, int level,
- const struct dev_printk_info *dev_info,
- const char *fmt, va_list args)
-{
- int printed_len;
- bool in_sched = false;
- unsigned long flags;
-
- /* Suppress unimportant messages after panic happens */
- if (unlikely(suppress_printk))
- return 0;
-
- if (unlikely(suppress_panic_printk) &&
- atomic_read(&panic_cpu) != raw_smp_processor_id())
- return 0;
+ memcpy(&r.info->dev_info, dev_info, sizeof(r.info->dev_info));
- if (level == LOGLEVEL_SCHED) {
- level = LOGLEVEL_DEFAULT;
- in_sched = true;
+ /* A message without a trailing newline can be continued. */
+ if (!(lflags & LOG_NEWLINE)) {
+ prb_commit(&e);
+ } else {
+ prb_final_commit(&e);
+ final_commit = true;
}
- boot_delay_msec(level);
- printk_delay();
-
- /* This stops the holder of console_sem just where we want him */
- logbuf_lock_irqsave(flags);
- printed_len = vprintk_store(facility, level, dev_info, fmt, args);
- logbuf_unlock_irqrestore(flags);
+ ret = text_len + trunc_msg_len;
+out:
+ /* only the kernel may perform synchronous printing */
+ if (facility == 0 && final_commit) {
+ struct console *con;
- /* If called from the scheduler, we can not call up(). */
- if (!in_sched) {
- /*
- * Disable preemption to avoid being preempted while holding
- * console_sem which would prevent anyone from printing to
- * console
- */
- preempt_disable();
- /*
- * Try to acquire and then immediately release the console
- * semaphore. The release will print out buffers and wake up
- * /dev/kmsg and syslog() users.
- */
- if (console_trylock_spinning())
- console_unlock();
- preempt_enable();
+ for_each_console(con) {
+ if (console_can_sync(con))
+ print_sync_until(con, seq + 1);
+ }
}
- wake_up_klogd();
- return printed_len;
+ printk_exit_irqrestore(irqflags);
+ return ret;
}
-EXPORT_SYMBOL(vprintk_emit);
+
+asmlinkage int vprintk_emit(int facility, int level,
+ const struct dev_printk_info *dev_info,
+ const char *fmt, va_list args)
+ {
+ int printed_len;
+
+ /* Suppress unimportant messages after panic happens */
+ if (unlikely(suppress_printk))
+ return 0;
+
+ if (level == LOGLEVEL_SCHED)
+ level = LOGLEVEL_DEFAULT;
+ printed_len = vprintk_store(facility, level, dev_info, fmt, args);
+
+ wake_up_klogd();
+ return printed_len;
+ }
+ EXPORT_SYMBOL(vprintk_emit);
+
+__printf(1, 0)
+static int vprintk_default(const char *fmt, va_list args)
+ {
+ return vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, fmt, args);
+ }
+
+__printf(1, 0)
+static int vprintk_func(const char *fmt, va_list args)
+ {
+#ifdef CONFIG_KGDB_KDB
+ /* Allow to pass printk() to kdb but avoid a recursion. */
+ if (unlikely(kdb_trap_printk && kdb_printf_cpu < 0))
+ return vkdb_printf(KDB_MSGSRC_PRINTK, fmt, args);
+#endif
+ return vprintk_default(fmt, args);
+ }
asmlinkage int vprintk(const char *fmt, va_list args)
{
@@ -2118,12 +2159,6 @@ asmlinkage int vprintk(const char *fmt, va_list args)
}
EXPORT_SYMBOL(vprintk);
-int vprintk_default(const char *fmt, va_list args)
-{
- return vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, fmt, args);
-}
-EXPORT_SYMBOL_GPL(vprintk_default);
-
/**
* printk - print a kernel message
* @fmt: format string
@@ -2158,38 +2193,158 @@ asmlinkage __visible int printk(const char *fmt, ...)
}
EXPORT_SYMBOL(printk);
-#else /* CONFIG_PRINTK */
+static int printk_kthread_func(void *data)
+{
+ struct console *con = data;
+ unsigned long dropped = 0;
+ char *dropped_text = NULL;
+ struct printk_info info;
+ struct printk_record r;
+ char *ext_text = NULL;
+ size_t dropped_len;
+ int ret = -ENOMEM;
+ char *text = NULL;
+ char *write_text;
+ u64 printk_seq;
+ size_t len;
+ int error;
+ u64 seq;
-#define LOG_LINE_MAX 0
-#define PREFIX_MAX 0
-#define printk_time false
+ if (con->flags & CON_EXTENDED) {
+ ext_text = kmalloc(CONSOLE_EXT_LOG_MAX, GFP_KERNEL);
+ if (!ext_text)
+ goto out;
+ }
+ text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
+ dropped_text = kmalloc(64, GFP_KERNEL);
+ if (!text || !dropped_text)
+ goto out;
-#define prb_read_valid(rb, seq, r) false
-#define prb_first_valid_seq(rb) 0
+ if (con->flags & CON_EXTENDED)
+ write_text = ext_text;
+ else
+ write_text = text;
-static u64 syslog_seq;
-static u64 console_seq;
-static u64 exclusive_console_stop_seq;
-static unsigned long console_dropped;
+ seq = atomic64_read(&con->printk_seq);
+
+ prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);
+
+ for (;;) {
+ error = wait_event_interruptible(log_wait,
+ prb_read_valid(prb, seq, &r) || kthread_should_stop());
+
+ if (kthread_should_stop())
+ break;
+
+ if (error)
+ continue;
+
+ if (seq != r.info->seq) {
+ dropped += r.info->seq - seq;
+ seq = r.info->seq;
+ }
+
+ seq++;
+
+ if (!(con->flags & CON_ENABLED))
+ continue;
-static size_t record_print_text(const struct printk_record *r,
- bool syslog, bool time)
+ if (suppress_message_printing(r.info->level))
+ continue;
+
+ if (con->flags & CON_EXTENDED) {
+ len = info_print_ext_header(ext_text,
+ CONSOLE_EXT_LOG_MAX,
+ r.info);
+ len += msg_print_ext_body(ext_text + len,
+ CONSOLE_EXT_LOG_MAX - len,
+ &r.text_buf[0], r.info->text_len,
+ &r.info->dev_info);
+ } else {
+ len = record_print_text(&r,
+ console_msg_format & MSG_FORMAT_SYSLOG,
+ printk_time);
+ }
+
+ printk_seq = atomic64_read(&con->printk_seq);
+
+ console_lock();
+ console_may_schedule = 0;
+
+ if (kernel_sync_mode() && con->write_atomic) {
+ console_unlock();
+ break;
+ }
+
+ if (!(con->flags & CON_EXTENDED) && dropped) {
+ dropped_len = snprintf(dropped_text, 64,
+ "** %lu printk messages dropped **\n",
+ dropped);
+ dropped = 0;
+
+ con->write(con, dropped_text, dropped_len);
+ printk_delay(r.info->level);
+ }
+
+ con->write(con, write_text, len);
+ if (len)
+ printk_delay(r.info->level);
+
+ atomic64_cmpxchg_relaxed(&con->printk_seq, printk_seq, seq);
+
+ console_unlock();
+ }
+out:
+ kfree(dropped_text);
+ kfree(text);
+ kfree(ext_text);
+ pr_info("%sconsole [%s%d]: printing thread stopped\n",
+ (con->flags & CON_BOOT) ? "boot" : "",
+ con->name, con->index);
+ return ret;
+}
+
+/* Must be called within console_lock(). */
+static void start_printk_kthread(struct console *con)
{
- return 0;
+ con->thread = kthread_run(printk_kthread_func, con,
+ "pr/%s%d", con->name, con->index);
+ if (IS_ERR(con->thread)) {
+ pr_err("%sconsole [%s%d]: unable to start printing thread\n",
+ (con->flags & CON_BOOT) ? "boot" : "",
+ con->name, con->index);
+ return;
+ }
+ pr_info("%sconsole [%s%d]: printing thread started\n",
+ (con->flags & CON_BOOT) ? "boot" : "",
+ con->name, con->index);
}
-static ssize_t info_print_ext_header(char *buf, size_t size,
- struct printk_info *info)
+
+/* protected by console_lock */
+static bool kthreads_started;
+
+/* Must be called within console_lock(). */
+static void console_try_thread(struct console *con)
{
- return 0;
+ if (kthreads_started) {
+ start_printk_kthread(con);
+ return;
+ }
+
+ /*
+ * The printing threads have not been started yet. If this console
+ * can print synchronously, print all unprinted messages.
+ */
+ if (console_can_sync(con))
+ print_sync_until(con, prb_next_seq(prb));
}
-static ssize_t msg_print_ext_body(char *buf, size_t size,
- char *text, size_t text_len,
- struct dev_printk_info *dev_info) { return 0; }
-static void console_lock_spinning_enable(void) { }
-static int console_lock_spinning_disable_and_check(void) { return 0; }
-static void call_console_drivers(const char *ext_text, size_t ext_len,
- const char *text, size_t len) {}
-static bool suppress_message_printing(int level) { return false; }
+
+#else /* CONFIG_PRINTK */
+
+#define prb_first_valid_seq(rb) 0
+#define prb_next_seq(rb) 0
+
+#define console_try_thread(con)
#endif /* CONFIG_PRINTK */
@@ -2434,21 +2589,6 @@ int is_console_locked(void)
}
EXPORT_SYMBOL(is_console_locked);
-/*
- * Check if we have any console that is capable of printing while cpu is
- * booting or shutting down. Requires console_sem.
- */
-static int have_callable_console(void)
-{
- struct console *con;
-
- for_each_console(con)
- if ((con->flags & CON_ENABLED) &&
- (con->flags & CON_ANYTIME))
- return 1;
-
- return 0;
-}
/*
* Return true when this CPU should unlock console_sem without pushing all
@@ -2469,17 +2609,6 @@ static bool abandon_console_lock_in_panic(void)
return atomic_read(&panic_cpu) != raw_smp_processor_id();
}
-/*
- * Can we actually use the console at this time on this cpu?
- *
- * Console drivers may assume that per-cpu resources have been allocated. So
- * unless they're explicitly marked as being able to cope (CON_ANYTIME) don't
- * call them until this CPU is officially up.
- */
-static inline int can_use_console(void)
-{
- return cpu_online(raw_smp_processor_id()) || have_callable_console();
-}
/**
* console_unlock - unlock the console system
@@ -2497,154 +2626,12 @@ static inline int can_use_console(void)
*/
void console_unlock(void)
{
- static char ext_text[CONSOLE_EXT_LOG_MAX];
- static char text[LOG_LINE_MAX + PREFIX_MAX];
- static int panic_console_dropped;
- unsigned long flags;
- bool do_cond_resched, retry, locked = false;
- struct printk_info info;
- struct printk_record r;
-
if (console_suspended) {
- up_console_sem();
- return;
- }
-
- prb_rec_init_rd(&r, &info, text, sizeof(text));
-
- /*
- * Console drivers are called with interrupts disabled, so
- * @console_may_schedule should be cleared before; however, we may
- * end up dumping a lot of lines, for example, if called from
- * console registration path, and should invoke cond_resched()
- * between lines if allowable. Not doing so can cause a very long
- * scheduling stall on a slow console leading to RCU stall and
- * softlockup warnings which exacerbate the issue with more
- * messages practically incapacitating the system.
- *
- * console_trylock() is not able to detect the preemptive
- * context reliably. Therefore the value must be stored before
- * and cleared after the "again" goto label.
- */
- do_cond_resched = console_may_schedule;
-again:
- console_may_schedule = 0;
-
- /*
- * We released the console_sem lock, so we need to recheck if
- * cpu is online and (if not) is there at least one CON_ANYTIME
- * console.
- */
- if (!can_use_console()) {
- console_locked = 0;
- up_console_sem();
- return;
- }
-
- for (;;) {
- size_t ext_len = 0;
- size_t len;
-
- printk_safe_enter_irqsave(flags);
- raw_spin_lock(&logbuf_lock);
- locked = true;
-skip:
- if (!prb_read_valid(prb, console_seq, &r))
- break;
-
- if (console_seq != r.info->seq) {
- console_dropped += r.info->seq - console_seq;
- console_seq = r.info->seq;
- if (panic_in_progress() && panic_console_dropped++ > 10) {
- suppress_panic_printk = 1;
- pr_warn_once("Too many dropped messages. Supress message on non-panic CPUs to prevent livelock.\n");
- }
- }
-
- if (suppress_message_printing(r.info->level)) {
- /*
- * Skip record we have buffered and already printed
- * directly to the console when we received it, and
- * record that has level above the console loglevel.
- */
- console_seq++;
- goto skip;
- }
-
- /* Output to all consoles once old messages replayed. */
- if (unlikely(exclusive_console &&
- console_seq >= exclusive_console_stop_seq)) {
- exclusive_console = NULL;
- }
-
- /*
- * Handle extended console text first because later
- * record_print_text() will modify the record buffer in-place.
- */
- if (nr_ext_console_drivers) {
- ext_len = info_print_ext_header(ext_text,
- sizeof(ext_text),
- r.info);
- ext_len += msg_print_ext_body(ext_text + ext_len,
- sizeof(ext_text) - ext_len,
- &r.text_buf[0],
- r.info->text_len,
- &r.info->dev_info);
- }
- len = record_print_text(&r,
- console_msg_format & MSG_FORMAT_SYSLOG,
- printk_time);
- console_seq++;
- locked = false;
- raw_spin_unlock(&logbuf_lock);
-
- /*
- * While actively printing out messages, if another printk()
- * were to occur on another CPU, it may wait for this one to
- * finish. This task can not be preempted if there is a
- * waiter waiting to take over.
- */
- console_lock_spinning_enable();
-
- stop_critical_timings(); /* don't trace print latency */
- call_console_drivers(ext_text, ext_len, text, len);
- start_critical_timings();
-
- if (console_lock_spinning_disable_and_check()) {
- printk_safe_exit_irqrestore(flags);
- return;
- }
-
- /* Allow panic_cpu to take over the consoles safely */
- if (abandon_console_lock_in_panic())
- break;
-
- printk_safe_exit_irqrestore(flags);
-
- if (do_cond_resched)
- cond_resched();
- }
-
- console_locked = 0;
-
- if (likely(locked))
- raw_spin_unlock(&logbuf_lock);
-
- up_console_sem();
-
- /*
- * Someone could have filled up the buffer again, so re-check if there's
- * something to flush. In case we cannot trylock the console_sem again,
- * there's a new owner and the console_unlock() from them will do the
- * flush, no worries.
- */
- raw_spin_lock(&logbuf_lock);
- retry = prb_read_valid(prb, console_seq, NULL);
- raw_spin_unlock(&logbuf_lock);
- printk_safe_exit_irqrestore(flags);
-
- if (retry && !abandon_console_lock_in_panic() && console_trylock())
- goto again;
+ up_console_sem();
+ return;
+ }
+ console_locked = 0;
+ up_console_sem();
}
EXPORT_SYMBOL(console_unlock);
@@ -2694,23 +2681,20 @@ void console_unblank(void)
*/
void console_flush_on_panic(enum con_flush_mode mode)
{
- /*
- * If someone else is holding the console lock, trylock will fail
- * and may_schedule may be set. Ignore and proceed to unlock so
- * that messages are flushed out. As this can be called from any
- * context and we don't want to get preempted while flushing,
- * ensure may_schedule is cleared.
- */
- console_trylock();
+ struct console *c;
+ u64 seq;
+
+ if (!console_trylock())
+ return;
+
console_may_schedule = 0;
- if (mode == CONSOLE_REPLAY_ALL) {
- unsigned long flags;
+ if (mode == CONSOLE_REPLAY_ALL) {
+ seq = prb_first_valid_seq(prb);
+ for_each_console(c)
+ atomic64_set(&c->printk_seq, seq);
+ }
- logbuf_lock_irqsave(flags);
- console_seq = prb_first_valid_seq(prb);
- logbuf_unlock_irqrestore(flags);
- }
console_unlock();
}
EXPORT_SYMBOL(console_flush_on_panic);
@@ -2879,7 +2863,6 @@ static void try_enable_default_console(struct console *newcon)
*/
void register_console(struct console *newcon)
{
- unsigned long flags;
struct console *bcon = NULL;
int err;
@@ -2903,6 +2886,8 @@ void register_console(struct console *newcon)
}
}
+ newcon->thread = NULL;
+
if (console_drivers && console_drivers->flags & CON_BOOT)
bcon = console_drivers;
@@ -2934,8 +2919,10 @@ void register_console(struct console *newcon)
* the real console are the same physical device, it's annoying to
* see the beginning boot messages twice
*/
- if (bcon && ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV))
+ if (bcon && ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV)) {
newcon->flags &= ~CON_PRINTBUFFER;
+ newcon->flags |= CON_HANDOVER;
+ }
/*
* Put this console in the list - keep the
@@ -2957,26 +2944,12 @@ void register_console(struct console *newcon)
if (newcon->flags & CON_EXTENDED)
nr_ext_console_drivers++;
- if (newcon->flags & CON_PRINTBUFFER) {
- /*
- * console_unlock(); will print out the buffered messages
- * for us.
- */
- logbuf_lock_irqsave(flags);
- /*
- * We're about to replay the log buffer. Only do this to the
- * just-registered console to avoid excessive message spam to
- * the already-registered consoles.
- *
- * Set exclusive_console with disabled interrupts to reduce
- * race window with eventual console_flush_on_panic() that
- * ignores console_lock.
- */
- exclusive_console = newcon;
- exclusive_console_stop_seq = console_seq;
- console_seq = syslog_seq;
- logbuf_unlock_irqrestore(flags);
- }
+ if (newcon->flags & CON_PRINTBUFFER)
+ atomic64_set(&newcon->printk_seq, 0);
+ else
+ atomic64_set(&newcon->printk_seq, prb_next_seq(prb));
+
+ console_try_thread(newcon);
console_unlock();
console_sysfs_notify();
@@ -3050,6 +3023,9 @@ int unregister_console(struct console *console)
console_unlock();
console_sysfs_notify();
+ if (console->thread && !IS_ERR(console->thread))
+ kthread_stop(console->thread);
+
if (console->exit)
res = console->exit(console);
@@ -3132,6 +3108,15 @@ static int __init printk_late_init(void)
unregister_console(con);
}
}
+
+#ifdef CONFIG_PRINTK
+ console_lock();
+ for_each_console(con)
+ start_printk_kthread(con);
+ kthreads_started = true;
+ console_unlock();
+#endif
+
ret = cpuhp_setup_state_nocalls(CPUHP_PRINTK_DEAD, "printk:dead", NULL,
console_cpu_notify);
WARN_ON(ret < 0);
@@ -3147,7 +3132,6 @@ late_initcall(printk_late_init);
* Delayed printk version, for scheduler-internal messages:
*/
#define PRINTK_PENDING_WAKEUP 0x01
-#define PRINTK_PENDING_OUTPUT 0x02
static DEFINE_PER_CPU(int, printk_pending);
@@ -3155,14 +3139,8 @@ static void wake_up_klogd_work_func(struct irq_work *irq_work)
{
int pending = __this_cpu_xchg(printk_pending, 0);
- if (pending & PRINTK_PENDING_OUTPUT) {
- /* If trylock fails, someone else is doing the printing */
- if (console_trylock())
- console_unlock();
- }
-
if (pending & PRINTK_PENDING_WAKEUP)
- wake_up_interruptible(&log_wait);
+ wake_up_interruptible_all(&log_wait);
}
static DEFINE_PER_CPU(struct irq_work, wake_up_klogd_work) =
@@ -3181,25 +3159,10 @@ void wake_up_klogd(void)
preempt_enable();
}
-void defer_console_output(void)
-{
- if (!printk_percpu_data_ready())
- return;
-
- preempt_disable();
- __this_cpu_or(printk_pending, PRINTK_PENDING_OUTPUT);
- irq_work_queue(this_cpu_ptr(&wake_up_klogd_work));
- preempt_enable();
-}
-
-int vprintk_deferred(const char *fmt, va_list args)
+__printf(1, 0)
+static int vprintk_deferred(const char *fmt, va_list args)
{
- int r;
-
- r = vprintk_emit(0, LOGLEVEL_SCHED, NULL, fmt, args);
- defer_console_output();
-
- return r;
+ return vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, fmt, args);
}
int printk_deferred(const char *fmt, ...)
@@ -3338,8 +3301,26 @@ EXPORT_SYMBOL_GPL(kmsg_dump_reason_str);
*/
void kmsg_dump(enum kmsg_dump_reason reason)
{
+ struct kmsg_dumper_iter iter;
struct kmsg_dumper *dumper;
- unsigned long flags;
+
+ if (!oops_in_progress) {
+ /*
+ * If atomic consoles are available, activate kernel sync mode
+ * to make sure any final messages are visible. The trailing
+ * printk message is important to flush any pending messages.
+ */
+ if (have_atomic_console()) {
+ sync_mode = true;
+ pr_info("enabled sync mode\n");
+ }
+
+ /*
+ * Give the printing threads time to flush, allowing up to
+ * 1s of no printing forward progress before giving up.
+ */
+ pr_flush(1000, true);
+ }
rcu_read_lock();
list_for_each_entry_rcu(dumper, &dump_list, list) {
@@ -3357,25 +3338,18 @@ void kmsg_dump(enum kmsg_dump_reason reason)
continue;
/* initialize iterator with data about the stored records */
- dumper->active = true;
-
- logbuf_lock_irqsave(flags);
- dumper->cur_seq = clear_seq;
- dumper->next_seq = prb_next_seq(prb);
- logbuf_unlock_irqrestore(flags);
+ iter.active = true;
+ kmsg_dump_rewind(&iter);
/* invoke dumper which will iterate over records */
- dumper->dump(dumper, reason);
-
- /* reset iterator */
- dumper->active = false;
+ dumper->dump(dumper, reason, &iter);
}
rcu_read_unlock();
}
/**
- * kmsg_dump_get_line_nolock - retrieve one kmsg log line (unlocked version)
- * @dumper: registered kmsg dumper
+ * kmsg_dump_get_line - retrieve one kmsg log line
+ * @iter: kmsg dumper iterator
* @syslog: include the "<4>" prefixes
* @line: buffer to copy the line to
* @size: maximum size of the buffer
@@ -3389,11 +3363,9 @@ void kmsg_dump(enum kmsg_dump_reason reason)
*
* A return value of FALSE indicates that there are no more records to
* read.
- *
- * The function is similar to kmsg_dump_get_line(), but grabs no locks.
*/
-bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog,
- char *line, size_t size, size_t *len)
+bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog,
+ char *line, size_t size, size_t *len)
{
struct printk_info info;
unsigned int line_count;
@@ -3403,16 +3375,16 @@ bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog,
prb_rec_init_rd(&r, &info, line, size);
- if (!dumper->active)
+ if (!iter->active)
goto out;
/* Read text or count text lines? */
if (line) {
- if (!prb_read_valid(prb, dumper->cur_seq, &r))
+ if (!prb_read_valid(prb, iter->cur_seq, &r))
goto out;
l = record_print_text(&r, syslog, printk_time);
} else {
- if (!prb_read_valid_info(prb, dumper->cur_seq,
+ if (!prb_read_valid_info(prb, iter->cur_seq,
&info, &line_count)) {
goto out;
}
@@ -3421,48 +3393,18 @@ bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog,
}
- dumper->cur_seq = r.info->seq + 1;
+ iter->cur_seq = r.info->seq + 1;
ret = true;
out:
if (len)
*len = l;
return ret;
}
-
-/**
- * kmsg_dump_get_line - retrieve one kmsg log line
- * @dumper: registered kmsg dumper
- * @syslog: include the "<4>" prefixes
- * @line: buffer to copy the line to
- * @size: maximum size of the buffer
- * @len: length of line placed into buffer
- *
- * Start at the beginning of the kmsg buffer, with the oldest kmsg
- * record, and copy one record into the provided buffer.
- *
- * Consecutive calls will return the next available record moving
- * towards the end of the buffer with the youngest messages.
- *
- * A return value of FALSE indicates that there are no more records to
- * read.
- */
-bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
- char *line, size_t size, size_t *len)
-{
- unsigned long flags;
- bool ret;
-
- logbuf_lock_irqsave(flags);
- ret = kmsg_dump_get_line_nolock(dumper, syslog, line, size, len);
- logbuf_unlock_irqrestore(flags);
-
- return ret;
-}
EXPORT_SYMBOL_GPL(kmsg_dump_get_line);
/**
* kmsg_dump_get_buffer - copy kmsg log lines
- * @dumper: registered kmsg dumper
+ * @iter: kmsg dumper iterator
* @syslog: include the "<4>" prefixes
* @buf: buffer to copy the line to
* @size: maximum size of the buffer
@@ -3479,116 +3421,256 @@ EXPORT_SYMBOL_GPL(kmsg_dump_get_line);
* A return value of FALSE indicates that there are no more records to
* read.
*/
-bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
- char *buf, size_t size, size_t *len)
+bool kmsg_dump_get_buffer(struct kmsg_dumper_iter *iter, bool syslog,
+ char *buf, size_t size, size_t *len_out)
{
struct printk_info info;
- unsigned int line_count;
struct printk_record r;
- unsigned long flags;
u64 seq;
u64 next_seq;
- size_t l = 0;
+ size_t len = 0;
bool ret = false;
bool time = printk_time;
- prb_rec_init_rd(&r, &info, buf, size);
-
- if (!dumper->active || !buf || !size)
+ if (!iter->active || !buf || !size)
goto out;
- logbuf_lock_irqsave(flags);
- if (prb_read_valid_info(prb, dumper->cur_seq, &info, NULL)) {
- if (info.seq != dumper->cur_seq) {
+ if (prb_read_valid_info(prb, iter->cur_seq, &info, NULL)) {
+ if (info.seq != iter->cur_seq) {
/* messages are gone, move to first available one */
- dumper->cur_seq = info.seq;
+ iter->cur_seq = info.seq;
}
}
/* last entry */
- if (dumper->cur_seq >= dumper->next_seq) {
- logbuf_unlock_irqrestore(flags);
+ if (iter->cur_seq >= iter->next_seq)
goto out;
- }
- /* calculate length of entire buffer */
- seq = dumper->cur_seq;
- while (prb_read_valid_info(prb, seq, &info, &line_count)) {
- if (r.info->seq >= dumper->next_seq)
- break;
- l += get_record_print_text_size(&info, line_count, syslog, time);
- seq = r.info->seq + 1;
- }
-
- /* move first record forward until length fits into the buffer */
- seq = dumper->cur_seq;
- while (l >= size && prb_read_valid_info(prb, seq,
- &info, &line_count)) {
- if (r.info->seq >= dumper->next_seq)
- break;
- l -= get_record_print_text_size(&info, line_count, syslog, time);
- seq = r.info->seq + 1;
- }
+ /*
+ * Find first record that fits, including all following records,
+ * into the user-provided buffer for this dump. Pass in size-1
+ * because this function (by way of record_print_text()) will
+ * not write more than size-1 bytes of text into @buf.
+ */
+ seq = find_first_fitting_seq(iter->cur_seq, iter->next_seq,
+ size - 1, syslog, time);
- /* last message in next interation */
+ /*
+ * Next kmsg_dump_get_buffer() invocation will dump block of
+ * older records stored right before this one.
+ */
next_seq = seq;
- /* actually read text into the buffer now */
- l = 0;
- while (prb_read_valid(prb, seq, &r)) {
- if (r.info->seq >= dumper->next_seq)
- break;
+ prb_rec_init_rd(&r, &info, buf, size);
- l += record_print_text(&r, syslog, time);
+ len = 0;
+ prb_for_each_record(seq, prb, seq, &r) {
+ if (r.info->seq >= iter->next_seq)
+ break;
- /* adjust record to store to remaining buffer space */
- prb_rec_init_rd(&r, &info, buf + l, size - l);
+ len += record_print_text(&r, syslog, time);
- seq = r.info->seq + 1;
+ /* Adjust record to store to remaining buffer space. */
+ prb_rec_init_rd(&r, &info, buf + len, size - len);
}
- dumper->next_seq = next_seq;
+ iter->next_seq = next_seq;
ret = true;
- logbuf_unlock_irqrestore(flags);
out:
- if (len)
- *len = l;
+ if (len_out)
+ *len_out = len;
return ret;
}
EXPORT_SYMBOL_GPL(kmsg_dump_get_buffer);
/**
- * kmsg_dump_rewind_nolock - reset the iterator (unlocked version)
- * @dumper: registered kmsg dumper
+ * kmsg_dump_rewind - reset the iterator
+ * @iter: kmsg dumper iterator
*
* Reset the dumper's iterator so that kmsg_dump_get_line() and
* kmsg_dump_get_buffer() can be called again and used multiple
* times within the same dumper.dump() callback.
+ */
+void kmsg_dump_rewind(struct kmsg_dumper_iter *iter)
+{
+ iter->cur_seq = latched_seq_read_nolock(&clear_seq);
+ iter->next_seq = prb_next_seq(prb);
+}
+EXPORT_SYMBOL_GPL(kmsg_dump_rewind);
+
+#endif
+
+struct prb_cpulock {
+ atomic_t owner;
+ unsigned long __percpu *irqflags;
+};
+
+#define DECLARE_STATIC_PRINTKRB_CPULOCK(name) \
+static DEFINE_PER_CPU(unsigned long, _##name##_percpu_irqflags); \
+static struct prb_cpulock name = { \
+ .owner = ATOMIC_INIT(-1), \
+ .irqflags = &_##name##_percpu_irqflags, \
+}
+
+static bool __prb_trylock(struct prb_cpulock *cpu_lock,
+ unsigned int *cpu_store)
+{
+ unsigned long *flags;
+ unsigned int cpu;
+
+ cpu = get_cpu();
+
+ *cpu_store = atomic_read(&cpu_lock->owner);
+ /* memory barrier to ensure the current lock owner is visible */
+ smp_rmb();
+ if (*cpu_store == -1) {
+ flags = per_cpu_ptr(cpu_lock->irqflags, cpu);
+ local_irq_save(*flags);
+ if (atomic_try_cmpxchg_acquire(&cpu_lock->owner,
+ cpu_store, cpu)) {
+ return true;
+ }
+ local_irq_restore(*flags);
+ } else if (*cpu_store == cpu) {
+ return true;
+ }
+
+ put_cpu();
+ return false;
+}
+
+/*
+ * prb_lock: Perform a processor-reentrant spin lock.
+ * @cpu_lock: A pointer to the lock object.
+ * @cpu_store: A "flags" pointer to store lock status information.
+ *
+ * If no processor has the lock, the calling processor takes the lock and
+ * becomes the owner. If the calling processor is already the owner of the
+ * lock, this function succeeds immediately. If lock is locked by another
+ * processor, this function spins until the calling processor becomes the
+ * owner.
*
- * The function is similar to kmsg_dump_rewind(), but grabs no locks.
+ * It is safe to call this function from any context and state.
*/
-void kmsg_dump_rewind_nolock(struct kmsg_dumper *dumper)
+static void prb_lock(struct prb_cpulock *cpu_lock, unsigned int *cpu_store)
{
- dumper->cur_seq = clear_seq;
- dumper->next_seq = prb_next_seq(prb);
+ for (;;) {
+ if (__prb_trylock(cpu_lock, cpu_store))
+ break;
+ cpu_relax();
+ }
}
-/**
- * kmsg_dump_rewind - reset the iterator
- * @dumper: registered kmsg dumper
+/*
+ * prb_unlock: Perform a processor-reentrant spin unlock.
+ * @cpu_lock: A pointer to the lock object.
+ * @cpu_store: A "flags" object storing lock status information.
*
- * Reset the dumper's iterator so that kmsg_dump_get_line() and
- * kmsg_dump_get_buffer() can be called again and used multiple
- * times within the same dumper.dump() callback.
+ * Release the lock. The calling processor must be the owner of the lock.
+ *
+ * It is safe to call this function from any context and state.
*/
-void kmsg_dump_rewind(struct kmsg_dumper *dumper)
+static void prb_unlock(struct prb_cpulock *cpu_lock, unsigned int cpu_store)
{
- unsigned long flags;
+ unsigned long *flags;
+ unsigned int cpu;
+
+ cpu = atomic_read(&cpu_lock->owner);
+ atomic_set_release(&cpu_lock->owner, cpu_store);
+
+ if (cpu_store == -1) {
+ flags = per_cpu_ptr(cpu_lock->irqflags, cpu);
+ local_irq_restore(*flags);
+ }
- logbuf_lock_irqsave(flags);
- kmsg_dump_rewind_nolock(dumper);
- logbuf_unlock_irqrestore(flags);
+ put_cpu();
}
-EXPORT_SYMBOL_GPL(kmsg_dump_rewind);
-#endif
+DECLARE_STATIC_PRINTKRB_CPULOCK(printk_cpulock);
+
+void console_atomic_lock(unsigned int *flags)
+{
+ prb_lock(&printk_cpulock, flags);
+}
+EXPORT_SYMBOL(console_atomic_lock);
+
+void console_atomic_unlock(unsigned int flags)
+{
+ prb_unlock(&printk_cpulock, flags);
+}
+EXPORT_SYMBOL(console_atomic_unlock);
+
+static void pr_msleep(bool may_sleep, int ms)
+{
+ if (may_sleep) {
+ msleep(ms);
+ } else {
+ while (ms--)
+ udelay(1000);
+ }
+}
+
+/**
+ * pr_flush() - Wait for printing threads to catch up.
+ *
+ * @timeout_ms: The maximum time (in ms) to wait.
+ * @reset_on_progress: Reset the timeout if forward progress is seen.
+ *
+ * A value of 0 for @timeout_ms means no waiting will occur. A value of -1
+ * represents infinite waiting.
+ *
+ * If @reset_on_progress is true, the timeout will be reset whenever any
+ * printer has been seen to make some forward progress.
+ *
+ * Context: Any context.
+ * Return: true if all enabled printers are caught up.
+ */
+bool pr_flush(int timeout_ms, bool reset_on_progress)
+{
+ int remaining = timeout_ms;
+ struct console *con;
+ u64 last_diff = 0;
+ bool may_sleep;
+ u64 printk_seq;
+ u64 diff;
+ u64 seq;
+
+ may_sleep = (preemptible() &&
+ !in_softirq() &&
+ system_state >= SYSTEM_RUNNING);
+
+ seq = prb_next_seq(prb);
+
+ for (;;) {
+ diff = 0;
+
+ for_each_console(con) {
+ if (!(con->flags & CON_ENABLED))
+ continue;
+ printk_seq = atomic64_read(&con->printk_seq);
+ if (printk_seq < seq)
+ diff += seq - printk_seq;
+ }
+
+ if (diff != last_diff && reset_on_progress)
+ remaining = timeout_ms;
+
+ if (!diff || remaining == 0)
+ break;
+
+ if (remaining < 0) {
+ pr_msleep(may_sleep, 100);
+ } else if (remaining < 100) {
+ pr_msleep(may_sleep, remaining);
+ remaining = 0;
+ } else {
+ pr_msleep(may_sleep, 100);
+ remaining -= 100;
+ }
+
+ last_diff = diff;
+ }
+
+ return (diff == 0);
+}
+EXPORT_SYMBOL(pr_flush);
diff --git a/kernel/printk/printk_safe.c b/kernel/printk/printk_safe.c
index b774685cc..218e42566 100644
--- a/kernel/printk/printk_safe.c
+++ b/kernel/printk/printk_safe.c
@@ -15,295 +15,9 @@
#include "internal.h"
-/*
- * printk() could not take logbuf_lock in NMI context. Instead,
- * it uses an alternative implementation that temporary stores
- * the strings into a per-CPU buffer. The content of the buffer
- * is later flushed into the main ring buffer via IRQ work.
- *
- * The alternative implementation is chosen transparently
- * by examining current printk() context mask stored in @printk_context
- * per-CPU variable.
- *
- * The implementation allows to flush the strings also from another CPU.
- * There are situations when we want to make sure that all buffers
- * were handled or when IRQs are blocked.
- */
-
-#define SAFE_LOG_BUF_LEN ((1 << CONFIG_PRINTK_SAFE_LOG_BUF_SHIFT) - \
- sizeof(atomic_t) - \
- sizeof(atomic_t) - \
- sizeof(struct irq_work))
-
-struct printk_safe_seq_buf {
- atomic_t len; /* length of written data */
- atomic_t message_lost;
- struct irq_work work; /* IRQ work that flushes the buffer */
- unsigned char buffer[SAFE_LOG_BUF_LEN];
-};
-
-static DEFINE_PER_CPU(struct printk_safe_seq_buf, safe_print_seq);
static DEFINE_PER_CPU(int, printk_context);
-static DEFINE_RAW_SPINLOCK(safe_read_lock);
-
#ifdef CONFIG_PRINTK_NMI
-static DEFINE_PER_CPU(struct printk_safe_seq_buf, nmi_print_seq);
-#endif
-
-/* Get flushed in a more safe context. */
-static void queue_flush_work(struct printk_safe_seq_buf *s)
-{
- if (printk_percpu_data_ready())
- irq_work_queue(&s->work);
-}
-
-/*
- * Add a message to per-CPU context-dependent buffer. NMI and printk-safe
- * have dedicated buffers, because otherwise printk-safe preempted by
- * NMI-printk would have overwritten the NMI messages.
- *
- * The messages are flushed from irq work (or from panic()), possibly,
- * from other CPU, concurrently with printk_safe_log_store(). Should this
- * happen, printk_safe_log_store() will notice the buffer->len mismatch
- * and repeat the write.
- */
-static __printf(2, 0) int printk_safe_log_store(struct printk_safe_seq_buf *s,
- const char *fmt, va_list args)
-{
- int add;
- size_t len;
- va_list ap;
-
-again:
- len = atomic_read(&s->len);
-
- /* The trailing '\0' is not counted into len. */
- if (len >= sizeof(s->buffer) - 1) {
- atomic_inc(&s->message_lost);
- queue_flush_work(s);
- return 0;
- }
-
- /*
- * Make sure that all old data have been read before the buffer
- * was reset. This is not needed when we just append data.
- */
- if (!len)
- smp_rmb();
-
- va_copy(ap, args);
- add = vscnprintf(s->buffer + len, sizeof(s->buffer) - len, fmt, ap);
- va_end(ap);
- if (!add)
- return 0;
-
- /*
- * Do it once again if the buffer has been flushed in the meantime.
- * Note that atomic_cmpxchg() is an implicit memory barrier that
- * makes sure that the data were written before updating s->len.
- */
- if (atomic_cmpxchg(&s->len, len, len + add) != len)
- goto again;
-
- queue_flush_work(s);
- return add;
-}
-
-static inline void printk_safe_flush_line(const char *text, int len)
-{
- /*
- * Avoid any console drivers calls from here, because we may be
- * in NMI or printk_safe context (when in panic). The messages
- * must go only into the ring buffer at this stage. Consoles will
- * get explicitly called later when a crashdump is not generated.
- */
- printk_deferred("%.*s", len, text);
-}
-
-/* printk part of the temporary buffer line by line */
-static int printk_safe_flush_buffer(const char *start, size_t len)
-{
- const char *c, *end;
- bool header;
-
- c = start;
- end = start + len;
- header = true;
-
- /* Print line by line. */
- while (c < end) {
- if (*c == '\n') {
- printk_safe_flush_line(start, c - start + 1);
- start = ++c;
- header = true;
- continue;
- }
-
- /* Handle continuous lines or missing new line. */
- if ((c + 1 < end) && printk_get_level(c)) {
- if (header) {
- c = printk_skip_level(c);
- continue;
- }
-
- printk_safe_flush_line(start, c - start);
- start = c++;
- header = true;
- continue;
- }
-
- header = false;
- c++;
- }
-
- /* Check if there was a partial line. Ignore pure header. */
- if (start < end && !header) {
- static const char newline[] = KERN_CONT "\n";
-
- printk_safe_flush_line(start, end - start);
- printk_safe_flush_line(newline, strlen(newline));
- }
-
- return len;
-}
-
-static void report_message_lost(struct printk_safe_seq_buf *s)
-{
- int lost = atomic_xchg(&s->message_lost, 0);
-
- if (lost)
- printk_deferred("Lost %d message(s)!\n", lost);
-}
-
-/*
- * Flush data from the associated per-CPU buffer. The function
- * can be called either via IRQ work or independently.
- */
-static void __printk_safe_flush(struct irq_work *work)
-{
- struct printk_safe_seq_buf *s =
- container_of(work, struct printk_safe_seq_buf, work);
- unsigned long flags;
- size_t len;
- int i;
-
- /*
- * The lock has two functions. First, one reader has to flush all
- * available message to make the lockless synchronization with
- * writers easier. Second, we do not want to mix messages from
- * different CPUs. This is especially important when printing
- * a backtrace.
- */
- raw_spin_lock_irqsave(&safe_read_lock, flags);
-
- i = 0;
-more:
- len = atomic_read(&s->len);
-
- /*
- * This is just a paranoid check that nobody has manipulated
- * the buffer an unexpected way. If we printed something then
- * @len must only increase. Also it should never overflow the
- * buffer size.
- */
- if ((i && i >= len) || len > sizeof(s->buffer)) {
- const char *msg = "printk_safe_flush: internal error\n";
-
- printk_safe_flush_line(msg, strlen(msg));
- len = 0;
- }
-
- if (!len)
- goto out; /* Someone else has already flushed the buffer. */
-
- /* Make sure that data has been written up to the @len */
- smp_rmb();
- i += printk_safe_flush_buffer(s->buffer + i, len - i);
-
- /*
- * Check that nothing has got added in the meantime and truncate
- * the buffer. Note that atomic_cmpxchg() is an implicit memory
- * barrier that makes sure that the data were copied before
- * updating s->len.
- */
- if (atomic_cmpxchg(&s->len, len, 0) != len)
- goto more;
-
-out:
- report_message_lost(s);
- raw_spin_unlock_irqrestore(&safe_read_lock, flags);
-}
-
-/**
- * printk_safe_flush - flush all per-cpu nmi buffers.
- *
- * The buffers are flushed automatically via IRQ work. This function
- * is useful only when someone wants to be sure that all buffers have
- * been flushed at some point.
- */
-void printk_safe_flush(void)
-{
- int cpu;
-
- for_each_possible_cpu(cpu) {
-#ifdef CONFIG_PRINTK_NMI
- __printk_safe_flush(&per_cpu(nmi_print_seq, cpu).work);
-#endif
- __printk_safe_flush(&per_cpu(safe_print_seq, cpu).work);
- }
-}
-
-/**
- * printk_safe_flush_on_panic - flush all per-cpu nmi buffers when the system
- * goes down.
- *
- * Similar to printk_safe_flush() but it can be called even in NMI context when
- * the system goes down. It does the best effort to get NMI messages into
- * the main ring buffer.
- *
- * Note that it could try harder when there is only one CPU online.
- */
-void printk_safe_flush_on_panic(void)
-{
- /*
- * Make sure that we could access the main ring buffer.
- * Do not risk a double release when more CPUs are up.
- */
- if (raw_spin_is_locked(&logbuf_lock)) {
- if (num_online_cpus() > 1)
- return;
-
- debug_locks_off();
- raw_spin_lock_init(&logbuf_lock);
- }
-
- if (raw_spin_is_locked(&safe_read_lock)) {
- if (num_online_cpus() > 1)
- return;
-
- debug_locks_off();
- raw_spin_lock_init(&safe_read_lock);
- }
-
- printk_safe_flush();
-}
-EXPORT_SYMBOL_GPL(printk_safe_flush_on_panic);
-
-#ifdef CONFIG_PRINTK_NMI
-/*
- * Safe printk() for NMI context. It uses a per-CPU buffer to
- * store the message. NMIs are not nested, so there is always only
- * one writer running. But the buffer might get flushed from another
- * CPU, so we need to be careful.
- */
-static __printf(1, 0) int vprintk_nmi(const char *fmt, va_list args)
-{
- struct printk_safe_seq_buf *s = this_cpu_ptr(&nmi_print_seq);
-
- return printk_safe_log_store(s, fmt, args);
-}
-
void noinstr printk_nmi_enter(void)
{
this_cpu_add(printk_context, PRINTK_NMI_CONTEXT_OFFSET);
@@ -318,11 +32,6 @@ void noinstr printk_nmi_exit(void)
* Marks a code that might produce many messages in NMI context
* and the risk of losing them is more critical than eventual
* reordering.
- *
- * It has effect only when called in NMI context. Then printk()
- * will try to store the messages into the main logbuf directly
- * and use the per-CPU buffers only as a fallback when the lock
- * is not available.
*/
void printk_nmi_direct_enter(void)
{
@@ -335,27 +44,8 @@ void printk_nmi_direct_exit(void)
this_cpu_and(printk_context, ~PRINTK_NMI_DIRECT_CONTEXT_MASK);
}
-#else
-
-static __printf(1, 0) int vprintk_nmi(const char *fmt, va_list args)
-{
- return 0;
-}
-
#endif /* CONFIG_PRINTK_NMI */
-/*
- * Lock-less printk(), to avoid deadlocks should the printk() recurse
- * into itself. It uses a per-CPU buffer to store the message, just like
- * NMI.
- */
-static __printf(1, 0) int vprintk_safe(const char *fmt, va_list args)
-{
- struct printk_safe_seq_buf *s = this_cpu_ptr(&safe_print_seq);
-
- return printk_safe_log_store(s, fmt, args);
-}
-
/* Can be preempted by NMI. */
void printk_safe_enter(void)
{
@@ -379,47 +69,22 @@ __printf(1, 0) int vprintk_func(const char *fmt, va_list args)
#endif
/*
- * Try to use the main logbuf even in NMI. But avoid calling console
+ * Use the main logbuf even in NMI. But avoid calling console
* drivers that might have their own locks.
*/
- if ((this_cpu_read(printk_context) & PRINTK_NMI_DIRECT_CONTEXT_MASK) &&
- raw_spin_trylock(&logbuf_lock)) {
+ if (this_cpu_read(printk_context) &
+ (PRINTK_NMI_DIRECT_CONTEXT_MASK |
+ PRINTK_NMI_CONTEXT_MASK |
+ PRINTK_SAFE_CONTEXT_MASK)) {
int len;
+ printk_safe_enter_irqsave(flags);
len = vprintk_store(0, LOGLEVEL_DEFAULT, NULL, fmt, args);
- raw_spin_unlock(&logbuf_lock);
+ printk_safe_exit_irqrestore(flags);
defer_console_output();
return len;
}
- /* Use extra buffer in NMI when logbuf_lock is taken or in safe mode. */
- if (this_cpu_read(printk_context) & PRINTK_NMI_CONTEXT_MASK)
- return vprintk_nmi(fmt, args);
-
- /* Use extra buffer to prevent a recursion deadlock in safe mode. */
- if (this_cpu_read(printk_context) & PRINTK_SAFE_CONTEXT_MASK)
- return vprintk_safe(fmt, args);
-
/* No obstacles. */
return vprintk_default(fmt, args);
}
-
-void __init printk_safe_init(void)
-{
- int cpu;
-
- for_each_possible_cpu(cpu) {
- struct printk_safe_seq_buf *s;
-
- s = &per_cpu(safe_print_seq, cpu);
- init_irq_work(&s->work, __printk_safe_flush);
-
-#ifdef CONFIG_PRINTK_NMI
- s = &per_cpu(nmi_print_seq, cpu);
- init_irq_work(&s->work, __printk_safe_flush);
-#endif
- }
-
- /* Flush pending messages that did not have scheduled IRQ works. */
- printk_safe_flush();
-}
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 6d82fba43..8a65ec16c 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -197,7 +197,14 @@ static bool ptrace_freeze_traced(struct task_struct *task)
spin_lock_irq(&task->sighand->siglock);
if (task_is_traced(task) && !looks_like_a_spurious_pid(task) &&
!__fatal_signal_pending(task)) {
- task->state = __TASK_TRACED;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&task->pi_lock, flags);
+ if (task->state & __TASK_TRACED)
+ task->state = __TASK_TRACED;
+ else
+ task->saved_state = __TASK_TRACED;
+ raw_spin_unlock_irqrestore(&task->pi_lock, flags);
ret = true;
}
spin_unlock_irq(&task->sighand->siglock);
@@ -207,8 +214,8 @@ static bool ptrace_freeze_traced(struct task_struct *task)
static void ptrace_unfreeze_traced(struct task_struct *task)
{
- if (task->state != __TASK_TRACED)
- return;
+ unsigned long flags;
+ bool frozen = true;
WARN_ON(!task->ptrace || task->parent != current);
@@ -217,12 +224,19 @@ static void ptrace_unfreeze_traced(struct task_struct *task)
* Recheck state under the lock to close this race.
*/
spin_lock_irq(&task->sighand->siglock);
- if (task->state == __TASK_TRACED) {
- if (__fatal_signal_pending(task))
- wake_up_state(task, __TASK_TRACED);
- else
- task->state = TASK_TRACED;
- }
+
+ raw_spin_lock_irqsave(&task->pi_lock, flags);
+ if (task->state == __TASK_TRACED)
+ task->state = TASK_TRACED;
+ else if (task->saved_state == __TASK_TRACED)
+ task->saved_state = TASK_TRACED;
+ else
+ frozen = false;
+ raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+
+ if (frozen && __fatal_signal_pending(task))
+ wake_up_state(task, __TASK_TRACED);
+
spin_unlock_irq(&task->sighand->siglock);
}
diff --git a/kernel/rcu/Kconfig b/kernel/rcu/Kconfig
index b1d7aef10..5e11e30f4 100644
--- a/kernel/rcu/Kconfig
+++ b/kernel/rcu/Kconfig
@@ -190,8 +190,8 @@ config RCU_FAST_NO_HZ
config RCU_BOOST
bool "Enable RCU priority boosting"
- depends on RT_MUTEXES && PREEMPT_RCU && RCU_EXPERT
- default n
+ depends on (RT_MUTEXES && PREEMPT_RCU && RCU_EXPERT) || PREEMPT_RT
+ default y if PREEMPT_RT
help
This option boosts the priority of preempted RCU readers that
block the current preemptible RCU grace period for too long.
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 44a89a72e..3fa502e5e 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -101,8 +101,10 @@ static struct rcu_state rcu_state = {
static bool dump_tree;
module_param(dump_tree, bool, 0444);
/* By default, use RCU_SOFTIRQ instead of rcuc kthreads. */
-static bool use_softirq = true;
+static bool use_softirq = !IS_ENABLED(CONFIG_PREEMPT_RT);
+#ifndef CONFIG_PREEMPT_RT
module_param(use_softirq, bool, 0444);
+#endif
/* Control rcu_node-tree auto-balancing at boot time. */
static bool rcu_fanout_exact;
module_param(rcu_fanout_exact, bool, 0444);
diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index 0e3821783..2beba0dfd 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -56,8 +56,10 @@
#ifndef CONFIG_TINY_RCU
module_param(rcu_expedited, int, 0);
module_param(rcu_normal, int, 0);
-static int rcu_normal_after_boot;
+static int rcu_normal_after_boot = IS_ENABLED(CONFIG_PREEMPT_RT);
+#ifndef CONFIG_PREEMPT_RT
module_param(rcu_normal_after_boot, int, 0);
+#endif
#endif /* #ifndef CONFIG_TINY_RCU */
#ifdef CONFIG_DEBUG_LOCK_ALLOC
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 457eeebc7..bf88a1034 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -67,7 +67,11 @@ const_debug unsigned int sysctl_sched_features =
* Number of tasks to iterate in a single balance run.
* Limited because this is done with IRQs disabled.
*/
+#ifdef CONFIG_PREEMPT_RT
+const_debug unsigned int sysctl_sched_nr_migrate = 8;
+#else
const_debug unsigned int sysctl_sched_nr_migrate = 32;
+#endif
/*
* period over which we measure -rt task CPU usage in us.
@@ -860,9 +864,15 @@ static bool set_nr_if_polling(struct task_struct *p)
#endif
#endif
-static bool __wake_q_add(struct wake_q_head *head, struct task_struct *task)
+static bool __wake_q_add(struct wake_q_head *head, struct task_struct *task,
+ bool sleeper)
{
- struct wake_q_node *node = &task->wake_q;
+ struct wake_q_node *node;
+
+ if (sleeper)
+ node = &task->wake_q_sleeper;
+ else
+ node = &task->wake_q;
/*
* Atomically grab the task, if ->wake_q is !nil already it means
@@ -898,7 +908,13 @@ static bool __wake_q_add(struct wake_q_head *head, struct task_struct *task)
*/
void wake_q_add(struct wake_q_head *head, struct task_struct *task)
{
- if (__wake_q_add(head, task))
+ if (__wake_q_add(head, task, false))
+ get_task_struct(task);
+}
+
+void wake_q_add_sleeper(struct wake_q_head *head, struct task_struct *task)
+{
+ if (__wake_q_add(head, task, true))
get_task_struct(task);
}
@@ -921,28 +937,39 @@ void wake_q_add(struct wake_q_head *head, struct task_struct *task)
*/
void wake_q_add_safe(struct wake_q_head *head, struct task_struct *task)
{
- if (!__wake_q_add(head, task))
+ if (!__wake_q_add(head, task, false))
put_task_struct(task);
}
-void wake_up_q(struct wake_q_head *head)
+void __wake_up_q(struct wake_q_head *head, bool sleeper)
{
struct wake_q_node *node = head->first;
while (node != WAKE_Q_TAIL) {
struct task_struct *task;
- task = container_of(node, struct task_struct, wake_q);
+ if (sleeper)
+ task = container_of(node, struct task_struct, wake_q_sleeper);
+ else
+ task = container_of(node, struct task_struct, wake_q);
+
BUG_ON(!task);
/* Task can safely be re-inserted now: */
node = node->next;
- task->wake_q.next = NULL;
+ if (sleeper)
+ task->wake_q_sleeper.next = NULL;
+ else
+ task->wake_q.next = NULL;
/*
* wake_up_process() executes a full barrier, which pairs with
* the queueing in wake_q_add() so as not to miss wakeups.
*/
- wake_up_process(task);
+ if (sleeper)
+ wake_up_lock_sleeper(task);
+ else
+ wake_up_process(task);
+
put_task_struct(task);
}
}
@@ -978,6 +1005,48 @@ void resched_curr(struct rq *rq)
trace_sched_wake_idle_without_ipi(cpu);
}
+#ifdef CONFIG_PREEMPT_LAZY
+
+static int tsk_is_polling(struct task_struct *p)
+{
+#ifdef TIF_POLLING_NRFLAG
+ return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG);
+#else
+ return 0;
+#endif
+}
+
+void resched_curr_lazy(struct rq *rq)
+{
+ struct task_struct *curr = rq->curr;
+ int cpu;
+
+ if (!sched_feat(PREEMPT_LAZY)) {
+ resched_curr(rq);
+ return;
+ }
+
+ lockdep_assert_held(&rq->__lock);
+
+ if (test_tsk_need_resched(curr))
+ return;
+
+ if (test_tsk_need_resched_lazy(curr))
+ return;
+
+ set_tsk_need_resched_lazy(curr);
+
+ cpu = cpu_of(rq);
+ if (cpu == smp_processor_id())
+ return;
+
+ /* NEED_RESCHED_LAZY must be visible before we test polling */
+ smp_mb();
+ if (!tsk_is_polling(curr))
+ smp_send_reschedule(cpu);
+}
+#endif
+
void resched_cpu(int cpu)
{
struct rq *rq = cpu_rq(cpu);
@@ -2070,6 +2139,82 @@ void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags)
#ifdef CONFIG_SMP
+static void
+__do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask, u32 flags);
+
+static int __set_cpus_allowed_ptr(struct task_struct *p,
+ const struct cpumask *new_mask,
+ u32 flags);
+
+static void migrate_disable_switch(struct rq *rq, struct task_struct *p)
+{
+ if (likely(!p->migration_disabled))
+ return;
+
+ if (p->cpus_ptr != &p->cpus_mask)
+ return;
+
+ /*
+ * Violates locking rules! see comment in __do_set_cpus_allowed().
+ */
+ __do_set_cpus_allowed(p, cpumask_of(rq->cpu), SCA_MIGRATE_DISABLE);
+}
+
+void migrate_disable(void)
+{
+ struct task_struct *p = current;
+
+ if (p->migration_disabled) {
+ p->migration_disabled++;
+ return;
+ }
+
+ trace_sched_migrate_disable_tp(p);
+
+ preempt_disable();
+ this_rq()->nr_pinned++;
+ p->migration_disabled = 1;
+ preempt_lazy_disable();
+ preempt_enable();
+}
+EXPORT_SYMBOL_GPL(migrate_disable);
+
+void migrate_enable(void)
+{
+ struct task_struct *p = current;
+
+ if (p->migration_disabled > 1) {
+ p->migration_disabled--;
+ return;
+ }
+
+ /*
+ * Ensure stop_task runs either before or after this, and that
+ * __set_cpus_allowed_ptr(SCA_MIGRATE_ENABLE) doesn't schedule().
+ */
+ preempt_disable();
+ if (p->cpus_ptr != &p->cpus_mask)
+ __set_cpus_allowed_ptr(p, &p->cpus_mask, SCA_MIGRATE_ENABLE);
+ /*
+ * Mustn't clear migration_disabled() until cpus_ptr points back at the
+ * regular cpus_mask, otherwise things that race (eg.
+ * select_fallback_rq) get confused.
+ */
+ barrier();
+ p->migration_disabled = 0;
+ this_rq()->nr_pinned--;
+ preempt_lazy_enable();
+ preempt_enable();
+
+ trace_sched_migrate_enable_tp(p);
+}
+EXPORT_SYMBOL_GPL(migrate_enable);
+
+static inline bool rq_has_pinned_tasks(struct rq *rq)
+{
+ return rq->nr_pinned;
+}
+
/*
* Per-CPU kthreads are allowed to run on !active && online CPUs, see
* __set_cpus_allowed_ptr() and select_fallback_rq().
@@ -2079,7 +2224,7 @@ static inline bool is_cpu_allowed(struct task_struct *p, int cpu)
if (!cpumask_test_cpu(cpu, p->cpus_ptr))
return false;
- if (is_per_cpu_kthread(p))
+ if (is_per_cpu_kthread(p) || is_migration_disabled(p))
return cpu_online(cpu);
return cpu_active(cpu);
@@ -2124,8 +2269,21 @@ static struct rq *move_queued_task(struct rq *rq, struct rq_flags *rf,
}
struct migration_arg {
- struct task_struct *task;
- int dest_cpu;
+ struct task_struct *task;
+ int dest_cpu;
+ struct set_affinity_pending *pending;
+};
+
+/*
+ * @refs: number of wait_for_completion()
+ * @stop_pending: is @stop_work in use
+ */
+struct set_affinity_pending {
+ refcount_t refs;
+ unsigned int stop_pending;
+ struct completion done;
+ struct cpu_stop_work stop_work;
+ struct migration_arg arg;
};
/*
@@ -2158,15 +2316,17 @@ static struct rq *__migrate_task(struct rq *rq, struct rq_flags *rf,
static int migration_cpu_stop(void *data)
{
struct migration_arg *arg = data;
+ struct set_affinity_pending *pending = arg->pending;
struct task_struct *p = arg->task;
struct rq *rq = this_rq();
+ bool complete = false;
struct rq_flags rf;
/*
* The original target CPU might have gone down and we might
* be on another CPU but it doesn't matter.
*/
- local_irq_disable();
+ local_irq_save(rf.flags);
/*
* We need to explicitly wake pending tasks before running
* __migrate_task() such that we will not miss enforcing cpus_ptr
@@ -2176,21 +2336,121 @@ static int migration_cpu_stop(void *data)
raw_spin_lock(&p->pi_lock);
rq_lock(rq, &rf);
+
/*
* If task_rq(p) != rq, it cannot be migrated here, because we're
* holding rq->lock, if p->on_rq == 0 it cannot get enqueued because
* we're holding p->pi_lock.
*/
if (task_rq(p) == rq) {
+ if (is_migration_disabled(p))
+ goto out;
+
+ if (pending) {
+ if (p->migration_pending == pending)
+ p->migration_pending = NULL;
+ complete = true;
+
+ if (cpumask_test_cpu(task_cpu(p), &p->cpus_mask))
+ goto out;
+ }
+
if (task_on_rq_queued(p))
rq = __migrate_task(rq, &rf, p, arg->dest_cpu);
else
p->wake_cpu = arg->dest_cpu;
+
+ /*
+ * XXX __migrate_task() can fail, at which point we might end
+ * up running on a dodgy CPU, AFAICT this can only happen
+ * during CPU hotplug, at which point we'll get pushed out
+ * anyway, so it's probably not a big deal.
+ */
+
+ } else if (pending) {
+ /*
+ * This happens when we get migrated between migrate_enable()'s
+ * preempt_enable() and scheduling the stopper task. At that
+ * point we're a regular task again and not current anymore.
+ *
+ * A !PREEMPT kernel has a giant hole here, which makes it far
+ * more likely.
+ */
+
+ /*
+ * The task moved before the stopper got to run. We're holding
+ * ->pi_lock, so the allowed mask is stable - if it got
+ * somewhere allowed, we're done.
+ */
+ if (cpumask_test_cpu(task_cpu(p), p->cpus_ptr)) {
+ if (p->migration_pending == pending)
+ p->migration_pending = NULL;
+ complete = true;
+ goto out;
+ }
+
+ /*
+ * When migrate_enable() hits a rq mis-match we can't reliably
+ * determine is_migration_disabled() and so have to chase after
+ * it.
+ */
+ WARN_ON_ONCE(!pending->stop_pending);
+ task_rq_unlock(rq, p, &rf);
+ stop_one_cpu_nowait(task_cpu(p), migration_cpu_stop,
+ &pending->arg, &pending->stop_work);
+ return 0;
}
- rq_unlock(rq, &rf);
- raw_spin_unlock(&p->pi_lock);
+out:
+ if (pending)
+ pending->stop_pending = false;
+ task_rq_unlock(rq, p, &rf);
- local_irq_enable();
+ if (complete)
+ complete_all(&pending->done);
+
+ return 0;
+}
+
+int push_cpu_stop(void *arg)
+{
+ struct rq *lowest_rq = NULL, *rq = this_rq();
+ struct task_struct *p = arg;
+
+ raw_spin_lock_irq(&p->pi_lock);
+ raw_spin_lock(&rq->__lock);
+
+ if (task_rq(p) != rq)
+ goto out_unlock;
+
+ if (is_migration_disabled(p)) {
+ p->migration_flags |= MDF_PUSH;
+ goto out_unlock;
+ }
+
+ p->migration_flags &= ~MDF_PUSH;
+
+ if (p->sched_class->find_lock_rq)
+ lowest_rq = p->sched_class->find_lock_rq(p, rq);
+
+ if (!lowest_rq)
+ goto out_unlock;
+
+ // XXX validate p is still the highest prio task
+ if (task_rq(p) == rq) {
+ deactivate_task(rq, p, 0);
+ set_task_cpu(p, lowest_rq->cpu);
+ activate_task(lowest_rq, p, 0);
+ resched_curr(lowest_rq);
+ }
+
+ double_unlock_balance(rq, lowest_rq);
+
+out_unlock:
+ rq->push_busy = false;
+ raw_spin_unlock(&rq->__lock);
+ raw_spin_unlock_irq(&p->pi_lock);
+
+ put_task_struct(p);
return 0;
}
@@ -2198,18 +2458,39 @@ static int migration_cpu_stop(void *data)
* sched_class::set_cpus_allowed must do the below, but is not required to
* actually call this function.
*/
-void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask)
+void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask, u32 flags)
{
+ if (flags & (SCA_MIGRATE_ENABLE | SCA_MIGRATE_DISABLE)) {
+ p->cpus_ptr = new_mask;
+ return;
+ }
+
cpumask_copy(&p->cpus_mask, new_mask);
p->nr_cpus_allowed = cpumask_weight(new_mask);
}
-void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
+static void
+__do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask, u32 flags)
{
struct rq *rq = task_rq(p);
bool queued, running;
- lockdep_assert_held(&p->pi_lock);
+ /*
+ * This here violates the locking rules for affinity, since we're only
+ * supposed to change these variables while holding both rq->lock and
+ * p->pi_lock.
+ *
+ * HOWEVER, it magically works, because ttwu() is the only code that
+ * accesses these variables under p->pi_lock and only does so after
+ * smp_cond_load_acquire(&p->on_cpu, !VAL), and we're in __schedule()
+ * before finish_task().
+ *
+ * XXX do further audits, this smells like something putrid.
+ */
+ if (flags & SCA_MIGRATE_DISABLE)
+ SCHED_WARN_ON(!p->on_cpu);
+ else
+ lockdep_assert_held(&p->pi_lock);
queued = task_on_rq_queued(p);
running = task_current(rq, p);
@@ -2225,7 +2506,7 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
if (running)
put_prev_task(rq, p);
- p->sched_class->set_cpus_allowed(p, new_mask);
+ p->sched_class->set_cpus_allowed(p, new_mask, flags);
if (queued)
enqueue_task(rq, p, ENQUEUE_RESTORE | ENQUEUE_NOCLOCK);
@@ -2233,6 +2514,222 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
set_next_task(rq, p);
}
+void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
+{
+ __do_set_cpus_allowed(p, new_mask, 0);
+}
+
+/*
+ * This function is wildly self concurrent; here be dragons.
+ *
+ *
+ * When given a valid mask, __set_cpus_allowed_ptr() must block until the
+ * designated task is enqueued on an allowed CPU. If that task is currently
+ * running, we have to kick it out using the CPU stopper.
+ *
+ * Migrate-Disable comes along and tramples all over our nice sandcastle.
+ * Consider:
+ *
+ * Initial conditions: P0->cpus_mask = [0, 1]
+ *
+ * P0@CPU0 P1
+ *
+ * migrate_disable();
+ * <preempted>
+ * set_cpus_allowed_ptr(P0, [1]);
+ *
+ * P1 *cannot* return from this set_cpus_allowed_ptr() call until P0 executes
+ * its outermost migrate_enable() (i.e. it exits its Migrate-Disable region).
+ * This means we need the following scheme:
+ *
+ * P0@CPU0 P1
+ *
+ * migrate_disable();
+ * <preempted>
+ * set_cpus_allowed_ptr(P0, [1]);
+ * <blocks>
+ * <resumes>
+ * migrate_enable();
+ * __set_cpus_allowed_ptr();
+ * <wakes local stopper>
+ * `--> <woken on migration completion>
+ *
+ * Now the fun stuff: there may be several P1-like tasks, i.e. multiple
+ * concurrent set_cpus_allowed_ptr(P0, [*]) calls. CPU affinity changes of any
+ * task p are serialized by p->pi_lock, which we can leverage: the one that
+ * should come into effect at the end of the Migrate-Disable region is the last
+ * one. This means we only need to track a single cpumask (i.e. p->cpus_mask),
+ * but we still need to properly signal those waiting tasks at the appropriate
+ * moment.
+ *
+ * This is implemented using struct set_affinity_pending. The first
+ * __set_cpus_allowed_ptr() caller within a given Migrate-Disable region will
+ * setup an instance of that struct and install it on the targeted task_struct.
+ * Any and all further callers will reuse that instance. Those then wait for
+ * a completion signaled at the tail of the CPU stopper callback (1), triggered
+ * on the end of the Migrate-Disable region (i.e. outermost migrate_enable()).
+ *
+ *
+ * (1) In the cases covered above. There is one more where the completion is
+ * signaled within affine_move_task() itself: when a subsequent affinity request
+ * cancels the need for an active migration. Consider:
+ *
+ * Initial conditions: P0->cpus_mask = [0, 1]
+ *
+ * P0@CPU0 P1 P2
+ *
+ * migrate_disable();
+ * <preempted>
+ * set_cpus_allowed_ptr(P0, [1]);
+ * <blocks>
+ * set_cpus_allowed_ptr(P0, [0, 1]);
+ * <signal completion>
+ * <awakes>
+ *
+ * Note that the above is safe vs a concurrent migrate_enable(), as any
+ * pending affinity completion is preceded an uninstallion of
+ * p->migration_pending done with p->pi_lock held.
+ */
+static int affine_move_task(struct rq *rq, struct task_struct *p, struct rq_flags *rf,
+ int dest_cpu, unsigned int flags)
+{
+ struct set_affinity_pending my_pending = { }, *pending = NULL;
+ bool stop_pending, complete = false;
+
+ /* Can the task run on the task's current CPU? If so, we're done */
+ if (cpumask_test_cpu(task_cpu(p), &p->cpus_mask)) {
+ struct task_struct *push_task = NULL;
+
+ if ((flags & SCA_MIGRATE_ENABLE) &&
+ (p->migration_flags & MDF_PUSH) && !rq->push_busy) {
+ rq->push_busy = true;
+ push_task = get_task_struct(p);
+ }
+
+ /*
+ * If there are pending waiters, but no pending stop_work,
+ * then complete now.
+ */
+ pending = p->migration_pending;
+ if (pending && !pending->stop_pending) {
+ p->migration_pending = NULL;
+ complete = true;
+ }
+
+ task_rq_unlock(rq, p, rf);
+
+ if (push_task) {
+ stop_one_cpu_nowait(rq->cpu, push_cpu_stop,
+ p, &rq->push_work);
+ }
+
+ if (complete)
+ complete_all(&pending->done);
+
+ return 0;
+ }
+
+ if (!(flags & SCA_MIGRATE_ENABLE)) {
+ /* serialized by p->pi_lock */
+ if (!p->migration_pending) {
+ /* Install the request */
+ refcount_set(&my_pending.refs, 1);
+ init_completion(&my_pending.done);
+ my_pending.arg = (struct migration_arg) {
+ .task = p,
+ .dest_cpu = dest_cpu,
+ .pending = &my_pending,
+ };
+
+ p->migration_pending = &my_pending;
+ } else {
+ pending = p->migration_pending;
+ refcount_inc(&pending->refs);
+ /*
+ * Affinity has changed, but we've already installed a
+ * pending. migration_cpu_stop() *must* see this, else
+ * we risk a completion of the pending despite having a
+ * task on a disallowed CPU.
+ *
+ * Serialized by p->pi_lock, so this is safe.
+ */
+ pending->arg.dest_cpu = dest_cpu;
+ }
+ }
+ pending = p->migration_pending;
+ /*
+ * - !MIGRATE_ENABLE:
+ * we'll have installed a pending if there wasn't one already.
+ *
+ * - MIGRATE_ENABLE:
+ * we're here because the current CPU isn't matching anymore,
+ * the only way that can happen is because of a concurrent
+ * set_cpus_allowed_ptr() call, which should then still be
+ * pending completion.
+ *
+ * Either way, we really should have a @pending here.
+ */
+ if (WARN_ON_ONCE(!pending)) {
+ task_rq_unlock(rq, p, rf);
+ return -EINVAL;
+ }
+
+ if (task_running(rq, p) || p->state == TASK_WAKING) {
+ /*
+ * MIGRATE_ENABLE gets here because 'p == current', but for
+ * anything else we cannot do is_migration_disabled(), punt
+ * and have the stopper function handle it all race-free.
+ */
+ stop_pending = pending->stop_pending;
+ if (!stop_pending)
+ pending->stop_pending = true;
+
+ if (flags & SCA_MIGRATE_ENABLE)
+ p->migration_flags &= ~MDF_PUSH;
+
+ task_rq_unlock(rq, p, rf);
+
+ if (!stop_pending) {
+ stop_one_cpu_nowait(cpu_of(rq), migration_cpu_stop,
+ &pending->arg, &pending->stop_work);
+ }
+
+ if (flags & SCA_MIGRATE_ENABLE)
+ return 0;
+ } else {
+
+ if (!is_migration_disabled(p)) {
+ if (task_on_rq_queued(p))
+ rq = move_queued_task(rq, rf, p, dest_cpu);
+
+ if (!pending->stop_pending) {
+ p->migration_pending = NULL;
+ complete = true;
+ }
+ }
+ task_rq_unlock(rq, p, rf);
+
+ if (complete)
+ complete_all(&pending->done);
+ }
+
+ wait_for_completion(&pending->done);
+
+ if (refcount_dec_and_test(&pending->refs))
+ wake_up_var(&pending->refs); /* No UaF, just an address */
+
+ /*
+ * Block the original owner of &pending until all subsequent callers
+ * have seen the completion and decremented the refcount
+ */
+ wait_var_event(&my_pending.refs, !refcount_read(&my_pending.refs));
+
+ /* ARGH */
+ WARN_ON_ONCE(my_pending.stop_pending);
+
+ return 0;
+}
+
/*
* Change a given task's CPU affinity. Migrate the thread to a
* proper CPU and schedule it away if the CPU it's executing on
@@ -2243,7 +2740,8 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
* call is not atomic; no spinlocks may be held.
*/
static int __set_cpus_allowed_ptr(struct task_struct *p,
- const struct cpumask *new_mask, bool check)
+ const struct cpumask *new_mask,
+ u32 flags)
{
const struct cpumask *cpu_valid_mask = cpu_active_mask;
unsigned int dest_cpu;
@@ -2254,9 +2752,14 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
rq = task_rq_lock(p, &rf);
update_rq_clock(rq);
- if (p->flags & PF_KTHREAD) {
+ if (p->flags & PF_KTHREAD || is_migration_disabled(p)) {
/*
- * Kernel threads are allowed on online && !active CPUs
+ * Kernel threads are allowed on online && !active CPUs.
+ *
+ * Specifically, migration_disabled() tasks must not fail the
+ * cpumask_any_and_distribute() pick below, esp. so on
+ * SCA_MIGRATE_ENABLE, otherwise we'll not call
+ * set_cpus_allowed_common() and actually reset p->cpus_ptr.
*/
cpu_valid_mask = cpu_online_mask;
}
@@ -2265,13 +2768,22 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
* Must re-check here, to close a race against __kthread_bind(),
* sched_setaffinity() is not guaranteed to observe the flag.
*/
- if (check && (p->flags & PF_NO_SETAFFINITY)) {
+ if ((flags & SCA_CHECK) && (p->flags & PF_NO_SETAFFINITY)) {
ret = -EINVAL;
goto out;
}
- if (cpumask_equal(&p->cpus_mask, new_mask))
- goto out;
+ if (!(flags & SCA_MIGRATE_ENABLE)) {
+ if (cpumask_equal(&p->cpus_mask, new_mask))
+ goto out;
+
+ if (WARN_ON_ONCE(p == current &&
+ is_migration_disabled(p) &&
+ !cpumask_test_cpu(task_cpu(p), new_mask))) {
+ ret = -EBUSY;
+ goto out;
+ }
+ }
/*
* Picking a ~random cpu helps in cases where we are changing affinity
@@ -2284,7 +2796,7 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
goto out;
}
- do_set_cpus_allowed(p, new_mask);
+ __do_set_cpus_allowed(p, new_mask, flags);
if (p->flags & PF_KTHREAD) {
/*
@@ -2296,23 +2808,8 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
p->nr_cpus_allowed != 1);
}
- /* Can the task run on the task's current CPU? If so, we're done */
- if (cpumask_test_cpu(task_cpu(p), new_mask))
- goto out;
+ return affine_move_task(rq, p, &rf, dest_cpu, flags);
- if (task_running(rq, p) || p->state == TASK_WAKING) {
- struct migration_arg arg = { p, dest_cpu };
- /* Need help from migration thread: drop lock and wait. */
- task_rq_unlock(rq, p, &rf);
- stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg);
- return 0;
- } else if (task_on_rq_queued(p)) {
- /*
- * OK, since we're going to drop the lock immediately
- * afterwards anyway.
- */
- rq = move_queued_task(rq, &rf, p, dest_cpu);
- }
out:
task_rq_unlock(rq, p, &rf);
@@ -2321,7 +2818,7 @@ out:
int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
{
- return __set_cpus_allowed_ptr(p, new_mask, false);
+ return __set_cpus_allowed_ptr(p, new_mask, 0);
}
EXPORT_SYMBOL_GPL(set_cpus_allowed_ptr);
@@ -2362,6 +2859,8 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
* Clearly, migrating tasks to offline CPUs is a fairly daft thing.
*/
WARN_ON_ONCE(!cpu_online(new_cpu));
+
+ WARN_ON_ONCE(is_migration_disabled(p));
#endif
trace_sched_migrate_task(p, new_cpu);
@@ -2494,6 +2993,18 @@ out:
}
#endif /* CONFIG_NUMA_BALANCING */
+static bool check_task_state(struct task_struct *p, long match_state)
+{
+ bool match = false;
+
+ raw_spin_lock_irq(&p->pi_lock);
+ if (p->state == match_state || p->saved_state == match_state)
+ match = true;
+ raw_spin_unlock_irq(&p->pi_lock);
+
+ return match;
+}
+
/*
* wait_task_inactive - wait for a thread to unschedule.
*
@@ -2538,7 +3049,7 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
* is actually now running somewhere else!
*/
while (task_running(rq, p)) {
- if (match_state && unlikely(p->state != match_state))
+ if (match_state && !check_task_state(p, match_state))
return 0;
cpu_relax();
}
@@ -2553,7 +3064,8 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
running = task_running(rq, p);
queued = task_on_rq_queued(p);
ncsw = 0;
- if (!match_state || p->state == match_state)
+ if (!match_state || p->state == match_state ||
+ p->saved_state == match_state)
ncsw = p->nvcsw | LONG_MIN; /* sets MSB */
task_rq_unlock(rq, p, &rf);
@@ -2587,7 +3099,7 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
ktime_t to = NSEC_PER_SEC / HZ;
set_current_state(TASK_UNINTERRUPTIBLE);
- schedule_hrtimeout(&to, HRTIMER_MODE_REL);
+ schedule_hrtimeout(&to, HRTIMER_MODE_REL_HARD);
continue;
}
@@ -2692,6 +3204,12 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
}
fallthrough;
case possible:
+ /*
+ * XXX When called from select_task_rq() we only
+ * hold p->pi_lock and again violate locking order.
+ *
+ * More yuck to audit.
+ */
do_set_cpus_allowed(p, cpu_possible_mask);
state = fail;
break;
@@ -2726,7 +3244,7 @@ int select_task_rq(struct task_struct *p, int cpu, int sd_flags, int wake_flags)
{
lockdep_assert_held(&p->pi_lock);
- if (p->nr_cpus_allowed > 1)
+ if (p->nr_cpus_allowed > 1 && !is_migration_disabled(p))
cpu = p->sched_class->select_task_rq(p, cpu, sd_flags, wake_flags);
else
cpu = cpumask_any(p->cpus_ptr);
@@ -2749,6 +3267,7 @@ int select_task_rq(struct task_struct *p, int cpu, int sd_flags, int wake_flags)
void sched_set_stop_task(int cpu, struct task_struct *stop)
{
+ static struct lock_class_key stop_pi_lock;
struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 };
struct task_struct *old_stop = cpu_rq(cpu)->stop;
@@ -2764,6 +3283,20 @@ void sched_set_stop_task(int cpu, struct task_struct *stop)
sched_setscheduler_nocheck(stop, SCHED_FIFO, &param);
stop->sched_class = &stop_sched_class;
+
+ /*
+ * The PI code calls rt_mutex_setprio() with ->pi_lock held to
+ * adjust the effective priority of a task. As a result,
+ * rt_mutex_setprio() can trigger (RT) balancing operations,
+ * which can then trigger wakeups of the stop thread to push
+ * around the current task.
+ *
+ * The stop task itself will never be part of the PI-chain, it
+ * never blocks, therefore that ->pi_lock recursion is safe.
+ * Tell lockdep about this by placing the stop->pi_lock in its
+ * own class.
+ */
+ lockdep_set_class(&stop->pi_lock, &stop_pi_lock);
}
cpu_rq(cpu)->stop = stop;
@@ -2777,15 +3310,23 @@ void sched_set_stop_task(int cpu, struct task_struct *stop)
}
}
-#else
+#else /* CONFIG_SMP */
static inline int __set_cpus_allowed_ptr(struct task_struct *p,
- const struct cpumask *new_mask, bool check)
+ const struct cpumask *new_mask,
+ u32 flags)
{
return set_cpus_allowed_ptr(p, new_mask);
}
-#endif /* CONFIG_SMP */
+static inline void migrate_disable_switch(struct rq *rq, struct task_struct *p) { }
+
+static inline bool rq_has_pinned_tasks(struct rq *rq)
+{
+ return false;
+}
+
+#endif /* !CONFIG_SMP */
static void
ttwu_stat(struct task_struct *p, int cpu, int wake_flags)
@@ -3227,7 +3768,7 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
int cpu, success = 0;
preempt_disable();
- if (p == current) {
+ if (!IS_ENABLED(CONFIG_PREEMPT_RT) && p == current) {
/*
* We're waking current, this means 'p->on_rq' and 'task_cpu(p)
* == smp_processor_id()'. Together this means we can special
@@ -3257,8 +3798,26 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
*/
raw_spin_lock_irqsave(&p->pi_lock, flags);
smp_mb__after_spinlock();
- if (!(p->state & state))
+ if (!(p->state & state)) {
+ /*
+ * The task might be running due to a spinlock sleeper
+ * wakeup. Check the saved state and set it to running
+ * if the wakeup condition is true.
+ */
+ if (!(wake_flags & WF_LOCK_SLEEPER)) {
+ if (p->saved_state & state) {
+ p->saved_state = TASK_RUNNING;
+ success = 1;
+ }
+ }
goto unlock;
+ }
+ /*
+ * If this is a regular wakeup, then we can unconditionally
+ * clear the saved state of a "lock sleeper".
+ */
+ if (!(wake_flags & WF_LOCK_SLEEPER))
+ p->saved_state = TASK_RUNNING;
trace_sched_waking(p);
@@ -3447,6 +4006,18 @@ int wake_up_process(struct task_struct *p)
}
EXPORT_SYMBOL(wake_up_process);
+/**
+ * wake_up_lock_sleeper - Wake up a specific process blocked on a "sleeping lock"
+ * @p: The process to be woken up.
+ *
+ * Same as wake_up_process() above, but wake_flags=WF_LOCK_SLEEPER to indicate
+ * the nature of the wakeup.
+ */
+int wake_up_lock_sleeper(struct task_struct *p)
+{
+ return try_to_wake_up(p, TASK_UNINTERRUPTIBLE, WF_LOCK_SLEEPER);
+}
+
int wake_up_state(struct task_struct *p, unsigned int state)
{
return try_to_wake_up(p, state, 0);
@@ -3500,6 +4071,7 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p)
init_numa_balancing(clone_flags, p);
#ifdef CONFIG_SMP
p->wake_entry.u_flags = CSD_TYPE_TTWU;
+ p->migration_pending = NULL;
#endif
#ifdef CONFIG_BPF_SCHED
p->tag = 0;
@@ -3719,6 +4291,9 @@ int sched_fork(unsigned long clone_flags, struct task_struct *p)
p->on_cpu = 0;
#endif
init_task_preempt_count(p);
+#ifdef CONFIG_HAVE_PREEMPT_LAZY
+ task_thread_info(p)->preempt_lazy_count = 0;
+#endif
#ifdef CONFIG_SMP
plist_node_init(&p->pushable_tasks, MAX_PRIO);
RB_CLEAR_NODE(&p->pushable_dl_tasks);
@@ -3889,60 +4464,145 @@ __fire_sched_out_preempt_notifiers(struct task_struct *curr,
notifier->ops->sched_out(notifier, next);
}
-static __always_inline void
-fire_sched_out_preempt_notifiers(struct task_struct *curr,
- struct task_struct *next)
+
+static __always_inline void
+fire_sched_out_preempt_notifiers(struct task_struct *curr,
+ struct task_struct *next)
+{
+ if (static_branch_unlikely(&preempt_notifier_key))
+ __fire_sched_out_preempt_notifiers(curr, next);
+}
+
+#else /* !CONFIG_PREEMPT_NOTIFIERS */
+
+static inline void fire_sched_in_preempt_notifiers(struct task_struct *curr)
+{
+}
+
+static inline void
+fire_sched_out_preempt_notifiers(struct task_struct *curr,
+ struct task_struct *next)
+{
+}
+
+#endif /* CONFIG_PREEMPT_NOTIFIERS */
+
+static inline void prepare_task(struct task_struct *next)
+{
+#ifdef CONFIG_SMP
+ /*
+ * Claim the task as running, we do this before switching to it
+ * such that any running task will have this set.
+ *
+ * See the ttwu() WF_ON_CPU case and its ordering comment.
+ */
+ WRITE_ONCE(next->on_cpu, 1);
+#endif
+}
+
+static inline void finish_task(struct task_struct *prev)
+{
+#ifdef CONFIG_SMP
+ /*
+ * This must be the very last reference to @prev from this CPU. After
+ * p->on_cpu is cleared, the task can be moved to a different CPU. We
+ * must ensure this doesn't happen until the switch is completely
+ * finished.
+ *
+ * In particular, the load of prev->state in finish_task_switch() must
+ * happen before this.
+ *
+ * Pairs with the smp_cond_load_acquire() in try_to_wake_up().
+ */
+ smp_store_release(&prev->on_cpu, 0);
+#endif
+}
+
+#ifdef CONFIG_SMP
+
+static void do_balance_callbacks(struct rq *rq, struct callback_head *head)
+{
+ void (*func)(struct rq *rq);
+ struct callback_head *next;
+
+ lockdep_assert_held(&rq->__lock);
+
+ while (head) {
+ func = (void (*)(struct rq *))head->func;
+ next = head->next;
+ head->next = NULL;
+ head = next;
+
+ func(rq);
+ }
+}
+
+static inline struct callback_head *splice_balance_callbacks(struct rq *rq)
+{
+ struct callback_head *head = rq->balance_callback;
+
+ lockdep_assert_held(&rq->__lock);
+ if (head) {
+ rq->balance_callback = NULL;
+ rq->balance_flags &= ~BALANCE_WORK;
+ }
+
+ return head;
+}
+
+static void __balance_callbacks(struct rq *rq)
+{
+ do_balance_callbacks(rq, splice_balance_callbacks(rq));
+}
+
+static inline void balance_callbacks(struct rq *rq, struct callback_head *head)
+{
+ unsigned long flags;
+
+ if (unlikely(head)) {
+ raw_spin_lock_irqsave(&rq->__lock, flags);
+ do_balance_callbacks(rq, head);
+ raw_spin_unlock_irqrestore(&rq->__lock, flags);
+ }
+}
+
+static void balance_push(struct rq *rq);
+
+static inline void balance_switch(struct rq *rq)
{
- if (static_branch_unlikely(&preempt_notifier_key))
- __fire_sched_out_preempt_notifiers(curr, next);
+ if (likely(!rq->balance_flags))
+ return;
+
+ if (rq->balance_flags & BALANCE_PUSH) {
+ balance_push(rq);
+ return;
+ }
+
+ __balance_callbacks(rq);
}
-#else /* !CONFIG_PREEMPT_NOTIFIERS */
+#else
-static inline void fire_sched_in_preempt_notifiers(struct task_struct *curr)
+static inline void __balance_callbacks(struct rq *rq)
{
}
-static inline void
-fire_sched_out_preempt_notifiers(struct task_struct *curr,
- struct task_struct *next)
+static inline struct callback_head *splice_balance_callbacks(struct rq *rq)
{
+ return NULL;
}
-#endif /* CONFIG_PREEMPT_NOTIFIERS */
-
-static inline void prepare_task(struct task_struct *next)
+static inline void balance_callbacks(struct rq *rq, struct callback_head *head)
{
-#ifdef CONFIG_SMP
- /*
- * Claim the task as running, we do this before switching to it
- * such that any running task will have this set.
- *
- * See the smp_load_acquire(&p->on_cpu) case in ttwu() and
- * its ordering comment.
- */
- WRITE_ONCE(next->on_cpu, 1);
-#endif
}
-static inline void finish_task(struct task_struct *prev)
+static inline void balance_switch(struct rq *rq)
{
-#ifdef CONFIG_SMP
- /*
- * This must be the very last reference to @prev from this CPU. After
- * p->on_cpu is cleared, the task can be moved to a different CPU. We
- * must ensure this doesn't happen until the switch is completely
- * finished.
- *
- * In particular, the load of prev->state in finish_task_switch() must
- * happen before this.
- *
- * Pairs with the smp_cond_load_acquire() in try_to_wake_up().
- */
- smp_store_release(&prev->on_cpu, 0);
-#endif
}
+#endif
+
+
static inline void
prepare_lock_switch(struct rq *rq, struct task_struct *next, struct rq_flags *rf)
{
@@ -3983,6 +4643,22 @@ static inline void finish_lock_switch(struct rq *rq)
# define finish_arch_post_lock_switch() do { } while (0)
#endif
+static inline void kmap_local_sched_out(void)
+{
+#ifdef CONFIG_KMAP_LOCAL
+ if (unlikely(current->kmap_ctrl.idx))
+ __kmap_local_sched_out();
+#endif
+}
+
+static inline void kmap_local_sched_in(void)
+{
+#ifdef CONFIG_KMAP_LOCAL
+ if (unlikely(current->kmap_ctrl.idx))
+ __kmap_local_sched_in();
+#endif
+}
+
/**
* prepare_task_switch - prepare to switch tasks
* @rq: the runqueue preparing to switch
@@ -4005,6 +4681,7 @@ prepare_task_switch(struct rq *rq, struct task_struct *prev,
perf_event_task_sched_out(prev, next);
rseq_preempt(prev);
fire_sched_out_preempt_notifiers(prev, next);
+ kmap_local_sched_out();
prepare_task(next);
prepare_arch_switch(next);
}
@@ -4073,6 +4750,7 @@ static struct rq *finish_task_switch(struct task_struct *prev)
finish_lock_switch(rq);
finish_arch_post_lock_switch();
kcov_finish_switch(current);
+ kmap_local_sched_in();
fire_sched_in_preempt_notifiers(current);
/*
@@ -4089,63 +4767,19 @@ static struct rq *finish_task_switch(struct task_struct *prev)
*/
if (mm) {
membarrier_mm_sync_core_before_usermode(mm);
- mmdrop(mm);
+ mmdrop_delayed(mm);
}
if (unlikely(prev_state == TASK_DEAD)) {
if (prev->sched_class->task_dead)
prev->sched_class->task_dead(prev);
- /*
- * Remove function-return probe instances associated with this
- * task and put them back on the free list.
- */
- kprobe_flush_task(prev);
-
- /* Task is done with its stack. */
- put_task_stack(prev);
-
put_task_struct_rcu_user(prev);
}
return rq;
}
-#ifdef CONFIG_SMP
-
-/* rq->lock is NOT held, but preemption is disabled */
-static void __balance_callback(struct rq *rq)
-{
- struct callback_head *head, *next;
- void (*func)(struct rq *rq);
- unsigned long flags;
-
- raw_spin_rq_lock_irqsave(rq, flags);
- head = rq->balance_callback;
- rq->balance_callback = NULL;
- while (head) {
- func = (void (*)(struct rq *))head->func;
- next = head->next;
- head->next = NULL;
- head = next;
-
- func(rq);
- }
- raw_spin_rq_unlock_irqrestore(rq, flags);
-}
-
-static inline void balance_callback(struct rq *rq)
-{
- if (unlikely(rq->balance_callback))
- __balance_callback(rq);
-}
-
-#else
-
-static inline void balance_callback(struct rq *rq)
-{
-}
-#endif
/**
* schedule_tail - first thing a freshly forked thread must call.
@@ -4166,7 +4800,6 @@ asmlinkage __visible void schedule_tail(struct task_struct *prev)
*/
rq = finish_task_switch(prev);
- balance_callback(rq);
preempt_enable();
if (current->set_child_tid)
@@ -5327,7 +5960,7 @@ pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
*
* WARNING: must be called with preemption disabled!
*/
-static void __sched notrace __schedule(bool preempt)
+static void __sched notrace __schedule(bool preempt, bool spinning_lock)
{
struct task_struct *prev, *next;
unsigned long *switch_count;
@@ -5380,7 +6013,7 @@ static void __sched notrace __schedule(bool preempt)
* - ptrace_{,un}freeze_traced() can change ->state underneath us.
*/
prev_state = prev->state;
- if (!preempt && prev_state) {
+ if ((!preempt || spinning_lock) && prev_state) {
if (signal_pending_state(prev_state, prev)) {
prev->state = TASK_RUNNING;
} else {
@@ -5415,6 +6048,7 @@ static void __sched notrace __schedule(bool preempt)
next = pick_next_task(rq, prev, &rf);
clear_tsk_need_resched(prev);
+ clear_tsk_need_resched_lazy(prev);
clear_preempt_need_resched();
if (likely(prev != next)) {
@@ -5440,6 +6074,7 @@ static void __sched notrace __schedule(bool preempt)
*/
++*switch_count;
+ migrate_disable_switch(rq, prev);
psi_sched_switch(prev, next, !task_on_rq_queued(prev));
trace_sched_switch(preempt, prev, next);
@@ -5448,10 +6083,11 @@ static void __sched notrace __schedule(bool preempt)
rq = context_switch(rq, prev, next, &rf);
} else {
rq->clock_update_flags &= ~(RQCF_ACT_SKIP|RQCF_REQ_SKIP);
- rq_unlock_irq(rq, &rf);
- }
- balance_callback(rq);
+ rq_unpin_lock(rq, &rf);
+ __balance_callbacks(rq);
+ raw_spin_unlock_irq(&rq->__lock);
+ }
}
void __noreturn do_task_dead(void)
@@ -5462,7 +6098,7 @@ void __noreturn do_task_dead(void)
/* Tell freezer to ignore us: */
current->flags |= PF_NOFREEZE;
- __schedule(false);
+ __schedule(false, false);
BUG();
/* Avoid "noreturn function does return" - but don't continue if BUG() is a NOP: */
@@ -5495,9 +6131,6 @@ static inline void sched_submit_work(struct task_struct *tsk)
preempt_enable_no_resched();
}
- if (tsk_is_pi_blocked(tsk))
- return;
-
/*
* If we are going to sleep and we have plugged IO queued,
* make sure to submit it to avoid deadlocks.
@@ -5523,7 +6156,7 @@ asmlinkage __visible void __sched schedule(void)
sched_submit_work(tsk);
do {
preempt_disable();
- __schedule(false);
+ __schedule(false, false);
sched_preempt_enable_no_resched();
} while (need_resched());
sched_update_worker(tsk);
@@ -5551,7 +6184,7 @@ void __sched schedule_idle(void)
*/
WARN_ON_ONCE(current->state);
do {
- __schedule(false);
+ __schedule(false, false);
} while (need_resched());
}
@@ -5604,7 +6237,7 @@ static void __sched notrace preempt_schedule_common(void)
*/
preempt_disable_notrace();
preempt_latency_start(1);
- __schedule(true);
+ __schedule(true, false);
preempt_latency_stop(1);
preempt_enable_no_resched_notrace();
@@ -5615,6 +6248,30 @@ static void __sched notrace preempt_schedule_common(void)
} while (need_resched());
}
+#ifdef CONFIG_PREEMPT_LAZY
+/*
+ * If TIF_NEED_RESCHED is then we allow to be scheduled away since this is
+ * set by a RT task. Oterwise we try to avoid beeing scheduled out as long as
+ * preempt_lazy_count counter >0.
+ */
+static __always_inline int preemptible_lazy(void)
+{
+ if (test_thread_flag(TIF_NEED_RESCHED))
+ return 1;
+ if (current_thread_info()->preempt_lazy_count)
+ return 0;
+ return 1;
+}
+
+#else
+
+static inline int preemptible_lazy(void)
+{
+ return 1;
+}
+
+#endif
+
#ifdef CONFIG_PREEMPTION
/*
* This is the entry point to schedule() from in-kernel preemption
@@ -5628,12 +6285,26 @@ asmlinkage __visible void __sched notrace preempt_schedule(void)
*/
if (likely(!preemptible()))
return;
-
+ if (!preemptible_lazy())
+ return;
preempt_schedule_common();
}
NOKPROBE_SYMBOL(preempt_schedule);
EXPORT_SYMBOL(preempt_schedule);
+#ifdef CONFIG_PREEMPT_RT
+void __sched notrace preempt_schedule_lock(void)
+{
+ do {
+ preempt_disable();
+ __schedule(true, true);
+ sched_preempt_enable_no_resched();
+ } while (need_resched());
+}
+NOKPROBE_SYMBOL(preempt_schedule_lock);
+EXPORT_SYMBOL(preempt_schedule_lock);
+#endif
+
#ifdef CONFIG_PREEMPT_DYNAMIC
DEFINE_STATIC_CALL(preempt_schedule, __preempt_schedule_func);
EXPORT_STATIC_CALL(preempt_schedule);
@@ -5661,6 +6332,9 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void)
if (likely(!preemptible()))
return;
+ if (!preemptible_lazy())
+ return;
+
do {
/*
* Because the function tracer can trace preempt_count_sub()
@@ -5683,7 +6357,7 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void)
* an infinite recursion.
*/
prev_ctx = exception_enter();
- __schedule(true);
+ __schedule(true, false);
exception_exit(prev_ctx);
preempt_latency_stop(1);
@@ -5901,7 +6575,7 @@ asmlinkage __visible void __sched preempt_schedule_irq(void)
do {
preempt_disable();
local_irq_enable();
- __schedule(true);
+ __schedule(true, false);
local_irq_disable();
sched_preempt_enable_no_resched();
} while (need_resched());
@@ -6067,9 +6741,11 @@ void rt_mutex_setprio(struct task_struct *p, struct task_struct *pi_task)
out_unlock:
/* Avoid rq from going away on us: */
preempt_disable();
- __task_rq_unlock(rq, &rf);
- balance_callback(rq);
+ rq_unpin_lock(rq, &rf);
+ __balance_callbacks(rq);
+ raw_spin_unlock(&rq->__lock);
+
preempt_enable();
}
#else
@@ -6312,6 +6988,7 @@ static int __sched_setscheduler(struct task_struct *p,
int oldpolicy = -1, policy = attr->sched_policy;
int retval, oldprio, newprio, queued, running;
const struct sched_class *prev_class;
+ struct callback_head *head;
struct rq_flags rf;
int reset_on_fork;
int queue_flags = DEQUEUE_SAVE | DEQUEUE_MOVE | DEQUEUE_NOCLOCK;
@@ -6573,6 +7250,7 @@ change:
/* Avoid rq from going away on us: */
preempt_disable();
+ head = splice_balance_callbacks(rq);
task_rq_unlock(rq, p, &rf);
if (pi) {
@@ -6582,7 +7260,7 @@ change:
}
/* Run balance callbacks after we've adjusted the PI chain: */
- balance_callback(rq);
+ balance_callbacks(rq, head);
preempt_enable();
return 0;
@@ -7077,7 +7755,7 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask)
}
#endif
again:
- retval = __set_cpus_allowed_ptr(p, new_mask, true);
+ retval = __set_cpus_allowed_ptr(p, new_mask, SCA_CHECK);
if (!retval) {
cpuset_cpus_allowed(p, cpus_allowed);
@@ -7703,7 +8381,7 @@ void __init init_idle(struct task_struct *idle, int cpu)
*
* And since this is boot we can forgo the serialization.
*/
- set_cpus_allowed_common(idle, cpumask_of(cpu));
+ set_cpus_allowed_common(idle, cpumask_of(cpu), 0);
#endif
/*
* We're having a chicken and egg problem, even though we are
@@ -7730,7 +8408,9 @@ void __init init_idle(struct task_struct *idle, int cpu)
/* Set the preempt count _outside_ the spinlocks! */
init_idle_preempt_count(idle, cpu);
-
+#ifdef CONFIG_HAVE_PREEMPT_LAZY
+ task_thread_info(idle)->preempt_lazy_count = 0;
+#endif
/*
* The idle tasks have their own, simple scheduling class:
*/
@@ -7827,6 +8507,7 @@ void sched_setnuma(struct task_struct *p, int nid)
#endif /* CONFIG_NUMA_BALANCING */
#ifdef CONFIG_HOTPLUG_CPU
+
/*
* Ensure that the idle task is using init_mm right before its CPU goes
* offline.
@@ -7846,119 +8527,126 @@ void idle_task_exit(void)
/* finish_cpu(), as ran on the BP, will clean up the active_mm state */
}
-/*
- * Since this CPU is going 'away' for a while, fold any nr_active delta
- * we might have. Assumes we're called after migrate_tasks() so that the
- * nr_active count is stable. We need to take the teardown thread which
- * is calling this into account, so we hand in adjust = 1 to the load
- * calculation.
- *
- * Also see the comment "Global load-average calculations".
- */
-static void calc_load_migrate(struct rq *rq)
+static int __balance_push_cpu_stop(void *arg)
{
- long delta = calc_load_fold_active(rq, 1);
- if (delta)
- atomic_long_add(delta, &calc_load_tasks);
-}
+ struct task_struct *p = arg;
+ struct rq *rq = this_rq();
+ struct rq_flags rf;
+ int cpu;
-static struct task_struct *__pick_migrate_task(struct rq *rq)
-{
- const struct sched_class *class;
- struct task_struct *next;
+ raw_spin_lock_irq(&p->pi_lock);
+ rq_lock(rq, &rf);
- for_each_class(class) {
- next = class->pick_next_task(rq);
- if (next) {
- next->sched_class->put_prev_task(rq, next);
- return next;
- }
+ update_rq_clock(rq);
+
+ if (task_rq(p) == rq && task_on_rq_queued(p)) {
+ cpu = select_fallback_rq(rq->cpu, p);
+ rq = __migrate_task(rq, &rf, p, cpu);
}
- /* The idle class should always have a runnable task */
- BUG();
+ rq_unlock(rq, &rf);
+ raw_spin_unlock_irq(&p->pi_lock);
+
+ put_task_struct(p);
+
+ return 0;
}
+static DEFINE_PER_CPU(struct cpu_stop_work, push_work);
+
/*
- * Migrate all tasks from the rq, sleeping tasks will be migrated by
- * try_to_wake_up()->select_task_rq().
- *
- * Called with rq->lock held even though we'er in stop_machine() and
- * there's no concurrency possible, we hold the required locks anyway
- * because of lock validation efforts.
+ * Ensure we only run per-cpu kthreads once the CPU goes !active.
*/
-static void migrate_tasks(struct rq *dead_rq, struct rq_flags *rf)
+static void balance_push(struct rq *rq)
{
- struct rq *rq = dead_rq;
- struct task_struct *next, *stop = rq->stop;
- struct rq_flags orf = *rf;
- int dest_cpu;
+ struct task_struct *push_task = rq->curr;
+
+ lockdep_assert_held(&rq->__lock);
+ SCHED_WARN_ON(rq->cpu != smp_processor_id());
/*
- * Fudge the rq selection such that the below task selection loop
- * doesn't get stuck on the currently eligible stop task.
- *
- * We're currently inside stop_machine() and the rq is either stuck
- * in the stop_machine_cpu_stop() loop, or we're executing this code,
- * either way we should never end up calling schedule() until we're
- * done here.
+ * Both the cpu-hotplug and stop task are in this case and are
+ * required to complete the hotplug process.
*/
- rq->stop = NULL;
+ if (is_per_cpu_kthread(push_task) || is_migration_disabled(push_task)) {
+ /*
+ * If this is the idle task on the outgoing CPU try to wake
+ * up the hotplug control thread which might wait for the
+ * last task to vanish. The rcuwait_active() check is
+ * accurate here because the waiter is pinned on this CPU
+ * and can't obviously be running in parallel.
+ *
+ * On RT kernels this also has to check whether there are
+ * pinned and scheduled out tasks on the runqueue. They
+ * need to leave the migrate disabled section first.
+ */
+ if (!rq->nr_running && !rq_has_pinned_tasks(rq) &&
+ rcuwait_active(&rq->hotplug_wait)) {
+ raw_spin_unlock(&rq->__lock);
+ rcuwait_wake_up(&rq->hotplug_wait);
+ raw_spin_lock(&rq->__lock);
+ }
+ return;
+ }
+ get_task_struct(push_task);
/*
- * put_prev_task() and pick_next_task() sched
- * class method both need to have an up-to-date
- * value of rq->clock[_task]
+ * Temporarily drop rq->lock such that we can wake-up the stop task.
+ * Both preemption and IRQs are still disabled.
*/
- update_rq_clock(rq);
+ raw_spin_unlock(&rq->__lock);
+ stop_one_cpu_nowait(rq->cpu, __balance_push_cpu_stop, push_task,
+ this_cpu_ptr(&push_work));
+ /*
+ * At this point need_resched() is true and we'll take the loop in
+ * schedule(). The next pick is obviously going to be the stop task
+ * which is_per_cpu_kthread() and will push this task away.
+ */
+ raw_spin_lock(&rq->__lock);
+}
- for (;;) {
- /*
- * There's this thread running, bail when that's the only
- * remaining thread:
- */
- if (rq->nr_running == 1)
- break;
+static void balance_push_set(int cpu, bool on)
+{
+ struct rq *rq = cpu_rq(cpu);
+ struct rq_flags rf;
- next = __pick_migrate_task(rq);
+ rq_lock_irqsave(rq, &rf);
+ if (on)
+ rq->balance_flags |= BALANCE_PUSH;
+ else
+ rq->balance_flags &= ~BALANCE_PUSH;
+ rq_unlock_irqrestore(rq, &rf);
+}
- /*
- * Rules for changing task_struct::cpus_mask are holding
- * both pi_lock and rq->lock, such that holding either
- * stabilizes the mask.
- *
- * Drop rq->lock is not quite as disastrous as it usually is
- * because !cpu_active at this point, which means load-balance
- * will not interfere. Also, stop-machine.
- */
- rq_unlock(rq, rf);
- raw_spin_lock(&next->pi_lock);
- rq_relock(rq, rf);
+/*
+ * Invoked from a CPUs hotplug control thread after the CPU has been marked
+ * inactive. All tasks which are not per CPU kernel threads are either
+ * pushed off this CPU now via balance_push() or placed on a different CPU
+ * during wakeup. Wait until the CPU is quiescent.
+ */
+static void balance_hotplug_wait(void)
+{
+ struct rq *rq = this_rq();
- /*
- * Since we're inside stop-machine, _nothing_ should have
- * changed the task, WARN if weird stuff happened, because in
- * that case the above rq->lock drop is a fail too.
- */
- if (WARN_ON(task_rq(next) != rq || !task_on_rq_queued(next))) {
- raw_spin_unlock(&next->pi_lock);
- continue;
- }
+ rcuwait_wait_event(&rq->hotplug_wait,
+ rq->nr_running == 1 && !rq_has_pinned_tasks(rq),
+ TASK_UNINTERRUPTIBLE);
+}
- /* Find suitable destination for @next, with force if needed. */
- dest_cpu = select_fallback_rq(dead_rq->cpu, next);
- rq = __migrate_task(rq, rf, next, dest_cpu);
- if (rq != dead_rq) {
- rq_unlock(rq, rf);
- rq = dead_rq;
- *rf = orf;
- rq_relock(rq, rf);
- }
- raw_spin_unlock(&next->pi_lock);
- }
+#else
+
+static inline void balance_push(struct rq *rq)
+{
+}
+
+static inline void balance_push_set(int cpu, bool on)
+{
+}
- rq->stop = stop;
+static inline void balance_hotplug_wait(void)
+{
}
+
#endif /* CONFIG_HOTPLUG_CPU */
void set_rq_online(struct rq *rq)
@@ -8061,7 +8749,8 @@ int sched_cpu_activate(unsigned int cpu)
{
struct rq *rq = cpu_rq(cpu);
struct rq_flags rf;
-
+
+ balance_push_set(cpu, false);
/*
* When going up, increment the number of cores with SMT present.
*/
@@ -8097,6 +8786,8 @@ int sched_cpu_activate(unsigned int cpu)
int sched_cpu_deactivate(unsigned int cpu)
{
+ struct rq *rq = cpu_rq(cpu);
+ struct rq_flags rf;
int ret;
set_cpu_active(cpu, false);
@@ -8108,6 +8799,15 @@ int sched_cpu_deactivate(unsigned int cpu)
* Do sync before park smpboot threads to take care the rcu boost case.
*/
synchronize_rcu();
+ balance_push_set(cpu, true);
+
+ rq_lock_irqsave(rq, &rf);
+ if (rq->rd) {
+ update_rq_clock(rq);
+ BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
+ set_rq_offline(rq);
+ }
+ rq_unlock_irqrestore(rq, &rf);
/*
* When going down, decrement the number of cores with SMT present.
@@ -8151,6 +8851,41 @@ int sched_cpu_starting(unsigned int cpu)
}
#ifdef CONFIG_HOTPLUG_CPU
+
+/*
+ * Invoked immediately before the stopper thread is invoked to bring the
+ * CPU down completely. At this point all per CPU kthreads except the
+ * hotplug thread (current) and the stopper thread (inactive) have been
+ * either parked or have been unbound from the outgoing CPU. Ensure that
+ * any of those which might be on the way out are gone.
+ *
+ * If after this point a bound task is being woken on this CPU then the
+ * responsible hotplug callback has failed to do it's job.
+ * sched_cpu_dying() will catch it with the appropriate fireworks.
+ */
+int sched_cpu_wait_empty(unsigned int cpu)
+{
+ balance_hotplug_wait();
+ return 0;
+}
+
+/*
+ * Since this CPU is going 'away' for a while, fold any nr_active delta we
+ * might have. Called from the CPU stopper task after ensuring that the
+ * stopper is the last running task on the CPU, so nr_active count is
+ * stable. We need to take the teardown thread which is calling this into
+ * account, so we hand in adjust = 1 to the load calculation.
+ *
+ * Also see the comment "Global load-average calculations".
+ */
+static void calc_load_migrate(struct rq *rq)
+{
+ long delta = calc_load_fold_active(rq, 1);
+
+ if (delta)
+ atomic_long_add(delta, &calc_load_tasks);
+}
+
int sched_cpu_dying(unsigned int cpu)
{
struct rq *rq = cpu_rq(cpu);
@@ -8160,12 +8895,7 @@ int sched_cpu_dying(unsigned int cpu)
sched_tick_stop(cpu);
rq_lock_irqsave(rq, &rf);
- if (rq->rd) {
- BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
- set_rq_offline(rq);
- }
- migrate_tasks(rq, &rf);
- BUG_ON(rq->nr_running != 1);
+ BUG_ON(rq->nr_running != 1 || rq_has_pinned_tasks(rq));
rq_unlock_irqrestore(rq, &rf);
calc_load_migrate(rq);
@@ -8399,6 +9129,9 @@ void __init sched_init(void)
INIT_CSD(&rq->nohz_csd, nohz_csd_func, rq);
#endif
+#ifdef CONFIG_HOTPLUG_CPU
+ rcuwait_init(&rq->hotplug_wait);
+#endif
#endif /* CONFIG_SMP */
hrtick_rq_init(rq);
atomic_set(&rq->nr_iowait, 0);
@@ -8449,7 +9182,7 @@ void __init sched_init(void)
#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
static inline int preempt_count_equals(int preempt_offset)
{
- int nested = preempt_count() + rcu_preempt_depth();
+ int nested = preempt_count() + sched_rcu_preempt_depth();
return (nested == preempt_offset);
}
@@ -8546,6 +9279,39 @@ void __cant_sleep(const char *file, int line, int preempt_offset)
add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
}
EXPORT_SYMBOL_GPL(__cant_sleep);
+
+#ifdef CONFIG_SMP
+void __cant_migrate(const char *file, int line)
+{
+ static unsigned long prev_jiffy;
+
+ if (irqs_disabled())
+ return;
+
+ if (is_migration_disabled(current))
+ return;
+
+ if (!IS_ENABLED(CONFIG_PREEMPT_COUNT))
+ return;
+
+ if (preempt_count() > 0)
+ return;
+
+ if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
+ return;
+ prev_jiffy = jiffies;
+
+ pr_err("BUG: assuming non migratable context at %s:%d\n", file, line);
+ pr_err("in_atomic(): %d, irqs_disabled(): %d, migration_disabled() %u pid: %d, name: %s\n",
+ in_atomic(), irqs_disabled(), is_migration_disabled(current),
+ current->pid, current->comm);
+
+ debug_show_held_locks(current);
+ dump_stack();
+ add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
+}
+EXPORT_SYMBOL_GPL(__cant_migrate);
+#endif
#endif
#ifdef CONFIG_MAGIC_SYSRQ
diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c
index 8cb06c8c7..ceb03d76c 100644
--- a/kernel/sched/cpudeadline.c
+++ b/kernel/sched/cpudeadline.c
@@ -120,7 +120,7 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p,
const struct sched_dl_entity *dl_se = &p->dl;
if (later_mask &&
- cpumask_and(later_mask, cp->free_cpus, p->cpus_ptr)) {
+ cpumask_and(later_mask, cp->free_cpus, &p->cpus_mask)) {
unsigned long cap, max_cap = 0;
int cpu, max_cpu = -1;
@@ -151,7 +151,7 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p,
WARN_ON(best_cpu != -1 && !cpu_present(best_cpu));
- if (cpumask_test_cpu(best_cpu, p->cpus_ptr) &&
+ if (cpumask_test_cpu(best_cpu, &p->cpus_mask) &&
dl_time_before(dl_se->deadline, cp->elements[0].dl)) {
if (later_mask)
cpumask_set_cpu(best_cpu, later_mask);
diff --git a/kernel/sched/cpupri.c b/kernel/sched/cpupri.c
index 0033731a0..11c4df201 100644
--- a/kernel/sched/cpupri.c
+++ b/kernel/sched/cpupri.c
@@ -73,11 +73,11 @@ static inline int __cpupri_find(struct cpupri *cp, struct task_struct *p,
if (skip)
return 0;
- if (cpumask_any_and(p->cpus_ptr, vec->mask) >= nr_cpu_ids)
+ if (cpumask_any_and(&p->cpus_mask, vec->mask) >= nr_cpu_ids)
return 0;
if (lowest_mask) {
- cpumask_and(lowest_mask, p->cpus_ptr, vec->mask);
+ cpumask_and(lowest_mask, &p->cpus_mask, vec->mask);
/*
* We have to ensure that we have at least one bit
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index f03b3af2f..e1ffc9caf 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -44,12 +44,13 @@ static void irqtime_account_delta(struct irqtime *irqtime, u64 delta,
}
/*
- * Called before incrementing preempt_count on {soft,}irq_enter
+ * Called after incrementing preempt_count on {soft,}irq_enter
* and before decrementing preempt_count on {soft,}irq_exit.
*/
-void irqtime_account_irq(struct task_struct *curr)
+void irqtime_account_irq(struct task_struct *curr, unsigned int offset)
{
struct irqtime *irqtime = this_cpu_ptr(&cpu_irqtime);
+ unsigned int pc;
s64 delta;
int cpu;
@@ -59,6 +60,7 @@ void irqtime_account_irq(struct task_struct *curr)
cpu = smp_processor_id();
delta = sched_clock_cpu(cpu) - irqtime->irq_start_time;
irqtime->irq_start_time += delta;
+ pc = irq_count() - offset;
/*
* We do not account for softirq time from ksoftirqd here.
@@ -66,12 +68,11 @@ void irqtime_account_irq(struct task_struct *curr)
* in that case, so as not to confuse scheduler with a special task
* that do not consume any time, but still wants to run.
*/
- if (hardirq_count())
+ if (pc & HARDIRQ_MASK)
irqtime_account_delta(irqtime, delta, CPUTIME_IRQ);
- else if (in_serving_softirq() && curr != this_cpu_ksoftirqd())
+ else if ((pc & SOFTIRQ_OFFSET) && curr != this_cpu_ksoftirqd())
irqtime_account_delta(irqtime, delta, CPUTIME_SOFTIRQ);
}
-EXPORT_SYMBOL_GPL(irqtime_account_irq);
static u64 irqtime_tick_accounted(u64 maxtime)
{
@@ -418,24 +419,21 @@ void vtime_task_switch(struct task_struct *prev)
}
# endif
-/*
- * Archs that account the whole time spent in the idle task
- * (outside irq) as idle time can rely on this and just implement
- * vtime_account_kernel() and vtime_account_idle(). Archs that
- * have other meaning of the idle time (s390 only includes the
- * time spent by the CPU when it's in low power mode) must override
- * vtime_account().
- */
-#ifndef __ARCH_HAS_VTIME_ACCOUNT
-void vtime_account_irq_enter(struct task_struct *tsk)
+void vtime_account_irq(struct task_struct *tsk, unsigned int offset)
{
- if (!in_interrupt() && is_idle_task(tsk))
+ unsigned int pc = irq_count() - offset;
+
+ if (pc & HARDIRQ_OFFSET) {
+ vtime_account_hardirq(tsk);
+ } else if (pc & SOFTIRQ_OFFSET) {
+ vtime_account_softirq(tsk);
+ } else if (!IS_ENABLED(CONFIG_HAVE_VIRT_CPU_ACCOUNTING_IDLE) &&
+ is_idle_task(tsk)) {
vtime_account_idle(tsk);
- else
+ } else {
vtime_account_kernel(tsk);
+ }
}
-EXPORT_SYMBOL_GPL(vtime_account_irq_enter);
-#endif /* __ARCH_HAS_VTIME_ACCOUNT */
void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev,
u64 *ut, u64 *st)
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index cff58dba2..f89cbba9b 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -552,7 +552,7 @@ static int push_dl_task(struct rq *rq);
static inline bool need_pull_dl_task(struct rq *rq, struct task_struct *prev)
{
- return dl_task(prev);
+ return rq->online && dl_task(prev);
}
static DEFINE_PER_CPU(struct callback_head, dl_push_head);
@@ -1917,7 +1917,7 @@ static void task_fork_dl(struct task_struct *p)
static int pick_dl_task(struct rq *rq, struct task_struct *p, int cpu)
{
if (!task_running(rq, p) &&
- cpumask_test_cpu(cpu, p->cpus_ptr))
+ cpumask_test_cpu(cpu, &p->cpus_mask))
return 1;
return 0;
}
@@ -2007,8 +2007,8 @@ static int find_later_rq(struct task_struct *task)
return this_cpu;
}
- best_cpu = cpumask_first_and(later_mask,
- sched_domain_span(sd));
+ best_cpu = cpumask_any_and_distribute(later_mask,
+ sched_domain_span(sd));
/*
* Last chance: if a CPU being in both later_mask
* and current sd span is valid, that becomes our
@@ -2030,7 +2030,7 @@ static int find_later_rq(struct task_struct *task)
if (this_cpu != -1)
return this_cpu;
- cpu = cpumask_any(later_mask);
+ cpu = cpumask_any_distribute(later_mask);
if (cpu < nr_cpu_ids)
return cpu;
@@ -2095,7 +2095,7 @@ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq)
*/
next_task = pick_next_pushable_dl_task(rq);
if (unlikely(next_task != task ||
- !cpumask_test_cpu(later_rq->cpu, task->cpus_ptr))) {
+ !cpumask_test_cpu(later_rq->cpu, &task->cpus_mask))) {
double_unlock_balance(rq, later_rq);
later_rq = NULL;
break;
@@ -2139,6 +2139,9 @@ static int push_dl_task(struct rq *rq)
return 0;
retry:
+ if (is_migration_disabled(next_task))
+ return 0;
+
if (WARN_ON(next_task == rq->curr))
return 0;
@@ -2216,7 +2219,7 @@ static void push_dl_tasks(struct rq *rq)
static void pull_dl_task(struct rq *this_rq)
{
int this_cpu = this_rq->cpu, cpu;
- struct task_struct *p;
+ struct task_struct *p, *push_task;
bool resched = false;
struct rq *src_rq;
u64 dmin = LONG_MAX;
@@ -2246,6 +2249,7 @@ static void pull_dl_task(struct rq *this_rq)
continue;
/* Might drop this_rq->lock */
+ push_task = NULL;
double_lock_balance(this_rq, src_rq);
/*
@@ -2277,17 +2281,28 @@ static void pull_dl_task(struct rq *this_rq)
src_rq->curr->dl.deadline))
goto skip;
- resched = true;
-
- deactivate_task(src_rq, p, 0);
- set_task_cpu(p, this_cpu);
- activate_task(this_rq, p, 0);
- dmin = p->dl.deadline;
+ if (is_migration_disabled(p)) {
+ trace_sched_migrate_pull_tp(p);
+ push_task = get_push_task(src_rq);
+ } else {
+ deactivate_task(src_rq, p, 0);
+ set_task_cpu(p, this_cpu);
+ activate_task(this_rq, p, 0);
+ dmin = p->dl.deadline;
+ resched = true;
+ }
/* Is there any other task even earlier? */
}
skip:
double_unlock_balance(this_rq, src_rq);
+
+ if (push_task) {
+ raw_spin_unlock(&this_rq->__lock);
+ stop_one_cpu_nowait(src_rq->cpu, push_cpu_stop,
+ push_task, &src_rq->push_work);
+ raw_spin_lock(&this_rq->__lock);
+ }
}
if (resched)
@@ -2311,7 +2326,8 @@ static void task_woken_dl(struct rq *rq, struct task_struct *p)
}
static void set_cpus_allowed_dl(struct task_struct *p,
- const struct cpumask *new_mask)
+ const struct cpumask *new_mask,
+ u32 flags)
{
struct root_domain *src_rd;
struct rq *rq;
@@ -2340,7 +2356,7 @@ static void set_cpus_allowed_dl(struct task_struct *p,
raw_spin_unlock(&src_dl_b->lock);
}
- set_cpus_allowed_common(p, new_mask);
+ set_cpus_allowed_common(p, new_mask, flags);
}
/* Assumes rq->lock is held */
@@ -2548,6 +2564,7 @@ const struct sched_class dl_sched_class
.rq_online = rq_online_dl,
.rq_offline = rq_offline_dl,
.task_woken = task_woken_dl,
+ .find_lock_rq = find_lock_later_rq,
#endif
.task_tick = task_tick_dl,
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index a518d636f..7433aa10e 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -4915,7 +4915,7 @@ check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr)
#endif
if (delta_exec > ideal_runtime) {
- resched_curr(rq_of(cfs_rq));
+ resched_curr_lazy(rq_of(cfs_rq));
/*
* The current task ran long enough, ensure it doesn't get
* re-elected due to buddy favours.
@@ -4939,7 +4939,7 @@ check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr)
return;
if (delta > ideal_runtime)
- resched_curr(rq_of(cfs_rq));
+ resched_curr_lazy(rq_of(cfs_rq));
}
static void
@@ -5082,7 +5082,7 @@ entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued)
* validating it and just reschedule.
*/
if (queued) {
- resched_curr(rq_of(cfs_rq));
+ resched_curr_lazy(rq_of(cfs_rq));
return;
}
/*
@@ -5231,7 +5231,7 @@ static void __account_cfs_rq_runtime(struct cfs_rq *cfs_rq, u64 delta_exec)
* hierarchy can be throttled
*/
if (!assign_cfs_rq_runtime(cfs_rq) && likely(cfs_rq->curr))
- resched_curr(rq_of(cfs_rq));
+ resched_curr_lazy(rq_of(cfs_rq));
}
static __always_inline
@@ -6545,7 +6545,7 @@ static void hrtick_start_fair(struct rq *rq, struct task_struct *p)
if (delta < 0) {
if (rq->curr == p)
- resched_curr(rq);
+ resched_curr_lazy(rq);
return;
}
hrtick_start(rq, delta);
@@ -8575,7 +8575,7 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_
return;
preempt:
- resched_curr(rq);
+ resched_curr_lazy(rq);
/*
* Only set the backward buddy when the current task is still
* on the rq. This can happen when a wakeup gets interleaved
@@ -13534,7 +13534,7 @@ static void task_fork_fair(struct task_struct *p)
* 'current' within the tree based on its new key value.
*/
swap(curr->vruntime, se->vruntime);
- resched_curr(rq);
+ resched_curr_lazy(rq);
}
se->vruntime -= cfs_rq->min_vruntime;
@@ -13561,7 +13561,7 @@ prio_changed_fair(struct rq *rq, struct task_struct *p, int oldprio)
*/
if (rq->curr == p) {
if (p->prio > oldprio)
- resched_curr(rq);
+ resched_curr_lazy(rq);
} else
check_preempt_curr(rq, p, 0);
}
diff --git a/kernel/sched/features.h b/kernel/sched/features.h
index fb885b20b..51fd2ba3a 100644
--- a/kernel/sched/features.h
+++ b/kernel/sched/features.h
@@ -45,11 +45,19 @@ SCHED_FEAT(DOUBLE_TICK, false)
*/
SCHED_FEAT(NONTASK_CAPACITY, true)
+#ifdef CONFIG_PREEMPT_RT
+SCHED_FEAT(TTWU_QUEUE, false)
+# ifdef CONFIG_PREEMPT_LAZY
+SCHED_FEAT(PREEMPT_LAZY, true)
+# endif
+#else
+
/*
* Queue remote wakeups on the target CPU and process them
* using the scheduler IPI. Reduces rq->lock contention/bounces.
*/
SCHED_FEAT(TTWU_QUEUE, true)
+#endif
/*
* When doing wakeups, attempt to limit superfluous scans of the LLC domain.
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index ddbc857a2..9dc62a542 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -270,7 +270,7 @@ static void pull_rt_task(struct rq *this_rq);
static inline bool need_pull_rt_task(struct rq *rq, struct task_struct *prev)
{
/* Try to pull RT tasks here if we lower this rq's prio */
- return rq->rt.highest_prio.curr > prev->prio;
+ return rq->online && rq->rt.highest_prio.curr > prev->prio;
}
static inline int rt_overloaded(struct rq *rq)
@@ -1681,7 +1681,7 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu)
{
if (!task_running(rq, p) &&
- cpumask_test_cpu(cpu, p->cpus_ptr))
+ cpumask_test_cpu(cpu, &p->cpus_mask))
return 1;
return 0;
@@ -1775,8 +1775,8 @@ static int find_lowest_rq(struct task_struct *task)
return this_cpu;
}
- best_cpu = cpumask_first_and(lowest_mask,
- sched_domain_span(sd));
+ best_cpu = cpumask_any_and_distribute(lowest_mask,
+ sched_domain_span(sd));
if (best_cpu < nr_cpu_ids) {
rcu_read_unlock();
return best_cpu;
@@ -1793,7 +1793,7 @@ static int find_lowest_rq(struct task_struct *task)
if (this_cpu != -1)
return this_cpu;
- cpu = cpumask_any(lowest_mask);
+ cpu = cpumask_any_distribute(lowest_mask);
if (cpu < nr_cpu_ids)
return cpu;
@@ -1854,7 +1854,7 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
*/
struct task_struct *next_task = pick_next_pushable_task(rq);
if (unlikely(next_task != task ||
- !cpumask_test_cpu(lowest_rq->cpu, task->cpus_ptr))) {
+ !cpumask_test_cpu(lowest_rq->cpu, &task->cpus_mask))) {
double_unlock_balance(rq, lowest_rq);
lowest_rq = NULL;
break;
@@ -1878,7 +1878,7 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
* running task can migrate over to a CPU that is running a task
* of lesser priority.
*/
-static int push_rt_task(struct rq *rq)
+static int push_rt_task(struct rq *rq, bool pull)
{
struct task_struct *next_task;
struct rq *lowest_rq;
@@ -1892,6 +1892,39 @@ static int push_rt_task(struct rq *rq)
return 0;
retry:
+ if (is_migration_disabled(next_task)) {
+ struct task_struct *push_task = NULL;
+ int cpu;
+
+ if (!pull)
+ return 0;
+
+ trace_sched_migrate_pull_tp(next_task);
+
+ if (rq->push_busy)
+ return 0;
+
+ cpu = find_lowest_rq(rq->curr);
+ if (cpu == -1 || cpu == rq->cpu)
+ return 0;
+
+ /*
+ * Given we found a CPU with lower priority than @next_task,
+ * therefore it should be running. However we cannot migrate it
+ * to this other CPU, instead attempt to push the current
+ * running task on this CPU away.
+ */
+ push_task = get_push_task(rq);
+ if (push_task) {
+ raw_spin_unlock(&rq->__lock);
+ stop_one_cpu_nowait(rq->cpu, push_cpu_stop,
+ push_task, &rq->push_work);
+ raw_spin_lock(&rq->__lock);
+ }
+
+ return 0;
+ }
+
if (WARN_ON(next_task == rq->curr))
return 0;
@@ -1949,12 +1982,10 @@ retry:
deactivate_task(rq, next_task, 0);
set_task_cpu(next_task, lowest_rq->cpu);
activate_task(lowest_rq, next_task, 0);
- ret = 1;
-
resched_curr(lowest_rq);
+ ret = 1;
double_unlock_balance(rq, lowest_rq);
-
out:
put_task_struct(next_task);
@@ -1964,7 +1995,7 @@ out:
static void push_rt_tasks(struct rq *rq)
{
/* push_rt_task will return true if it moved an RT */
- while (push_rt_task(rq))
+ while (push_rt_task(rq, false))
;
}
@@ -2117,7 +2148,10 @@ void rto_push_irq_work_func(struct irq_work *work)
*/
if (has_pushable_tasks(rq)) {
raw_spin_rq_lock(rq);
- push_rt_tasks(rq);
+
+ while (push_rt_task(rq, true))
+ ;
+
raw_spin_rq_unlock(rq);
}
@@ -2142,7 +2176,7 @@ static void pull_rt_task(struct rq *this_rq)
{
int this_cpu = this_rq->cpu, cpu;
bool resched = false;
- struct task_struct *p;
+ struct task_struct *p, *push_task;
struct rq *src_rq;
int rt_overload_count = rt_overloaded(this_rq);
@@ -2189,6 +2223,7 @@ static void pull_rt_task(struct rq *this_rq)
* double_lock_balance, and another CPU could
* alter this_rq
*/
+ push_task = NULL;
double_lock_balance(this_rq, src_rq);
/*
@@ -2216,11 +2251,15 @@ static void pull_rt_task(struct rq *this_rq)
if (p->prio < src_rq->curr->prio)
goto skip;
- resched = true;
-
- deactivate_task(src_rq, p, 0);
- set_task_cpu(p, this_cpu);
- activate_task(this_rq, p, 0);
+ if (is_migration_disabled(p)) {
+ trace_sched_migrate_pull_tp(p);
+ push_task = get_push_task(src_rq);
+ } else {
+ deactivate_task(src_rq, p, 0);
+ set_task_cpu(p, this_cpu);
+ activate_task(this_rq, p, 0);
+ resched = true;
+ }
/*
* We continue with the search, just in
* case there's an even higher prio task
@@ -2230,6 +2269,13 @@ static void pull_rt_task(struct rq *this_rq)
}
skip:
double_unlock_balance(this_rq, src_rq);
+
+ if (push_task) {
+ raw_spin_unlock(&this_rq->__lock);
+ stop_one_cpu_nowait(src_rq->cpu, push_cpu_stop,
+ push_task, &src_rq->push_work);
+ raw_spin_lock(&this_rq->__lock);
+ }
}
if (resched)
@@ -2479,6 +2525,7 @@ const struct sched_class rt_sched_class
.rq_offline = rq_offline_rt,
.task_woken = task_woken_rt,
.switched_from = switched_from_rt,
+ .find_lock_rq = find_lock_lowest_rq,
#endif
.task_tick = task_tick_rt,
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index fe6342305..269837135 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1112,6 +1112,7 @@ struct rq {
unsigned long cpu_capacity_orig;
struct callback_head *balance_callback;
+ unsigned char balance_flags;
unsigned char nohz_idle_balance;
unsigned char idle_balance;
@@ -1142,6 +1143,10 @@ struct rq {
/* This is used to determine avg_idle's max value */
u64 max_idle_balance_cost;
+
+#ifdef CONFIG_HOTPLUG_CPU
+ struct rcuwait hotplug_wait;
+#endif
#endif /* CONFIG_SMP */
#ifdef CONFIG_IRQ_TIME_ACCOUNTING
@@ -1215,6 +1220,11 @@ struct rq {
unsigned char core_forceidle;
unsigned int core_forceidle_seq;
#endif
+#ifdef CONFIG_SMP
+ unsigned int nr_pinned;
+#endif
+ unsigned int push_busy;
+ struct cpu_stop_work push_work;
#if defined(CONFIG_QOS_SCHED_PRIO_LB) && !defined(__GENKSYMS__)
struct list_head cfs_offline_tasks;
@@ -1254,6 +1264,16 @@ static inline int cpu_of(struct rq *rq)
return 0;
#endif
}
+#define MDF_PUSH 0x01
+
+static inline bool is_migration_disabled(struct task_struct *p)
+{
+#ifdef CONFIG_SMP
+ return p->migration_disabled;
+#else
+ return false;
+#endif
+}
#ifdef CONFIG_QOS_SCHED
#ifdef CONFIG_QOS_SCHED_MULTILEVEL
@@ -1671,6 +1691,9 @@ static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
rf->clock_update_flags = 0;
#endif
+#if 0//def CONFIG_SMP
+ SCHED_WARN_ON(rq->balance_callback);
+#endif
}
static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
@@ -1851,6 +1874,9 @@ init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
#ifdef CONFIG_SMP
+#define BALANCE_WORK 0x01
+#define BALANCE_PUSH 0x02
+
static inline void
queue_balance_callback(struct rq *rq,
struct callback_head *head,
@@ -1858,12 +1884,13 @@ queue_balance_callback(struct rq *rq,
{
lockdep_assert_rq_held(rq);
- if (unlikely(head->next))
+ if (unlikely(head->next || (rq->balance_flags & BALANCE_PUSH)))
return;
head->func = (void (*)(struct callback_head *))func;
head->next = rq->balance_callback;
rq->balance_callback = head;
+ rq->balance_flags |= BALANCE_WORK;
}
#define rcu_dereference_check_sched_domain(p) \
@@ -2189,7 +2216,7 @@ static inline int task_on_rq_migrating(struct task_struct *p)
#define WF_SYNC 0x01 /* Waker goes to sleep after wakeup */
#define WF_FORK 0x02 /* Child wakeup after fork */
#define WF_MIGRATED 0x04 /* Internal use, task got migrated */
-
+#define WF_LOCK_SLEEPER 0x10 /* Wakeup spinlock "sleeper" */
/*
* To aid in avoiding the subversion of "niceness" due to uneven distribution
* of tasks with abnormal "nice" values across CPUs the contribution that
@@ -2270,10 +2297,13 @@ struct sched_class {
void (*task_woken)(struct rq *this_rq, struct task_struct *task);
void (*set_cpus_allowed)(struct task_struct *p,
- const struct cpumask *newmask);
+ const struct cpumask *newmask,
+ u32 flags);
void (*rq_online)(struct rq *rq);
void (*rq_offline)(struct rq *rq);
+
+ struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
#endif
void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
@@ -2363,13 +2393,38 @@ static inline bool sched_fair_runnable(struct rq *rq)
extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
extern struct task_struct *pick_next_task_idle(struct rq *rq);
+#define SCA_CHECK 0x01
+#define SCA_MIGRATE_DISABLE 0x02
+#define SCA_MIGRATE_ENABLE 0x04
+
#ifdef CONFIG_SMP
extern void update_group_capacity(struct sched_domain *sd, int cpu);
extern void trigger_load_balance(struct rq *rq);
-extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask);
+extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask, u32 flags);
+
+static inline struct task_struct *get_push_task(struct rq *rq)
+{
+ struct task_struct *p = rq->curr;
+
+ lockdep_assert_held(&rq->__lock);
+
+ if (rq->push_busy)
+ return NULL;
+
+ if (p->nr_cpus_allowed == 1)
+ return NULL;
+
+ if (p->migration_disabled)
+ return NULL;
+
+ rq->push_busy = true;
+ return get_task_struct(p);
+}
+
+extern int push_cpu_stop(void *arg);
#endif
@@ -2413,6 +2468,15 @@ extern void reweight_task(struct task_struct *p, int prio);
extern void resched_curr(struct rq *rq);
extern void resched_cpu(int cpu);
+#ifdef CONFIG_PREEMPT_LAZY
+extern void resched_curr_lazy(struct rq *rq);
+#else
+static inline void resched_curr_lazy(struct rq *rq)
+{
+ resched_curr(rq);
+}
+#endif
+
extern struct rt_bandwidth def_rt_bandwidth;
extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
diff --git a/kernel/sched/swait.c b/kernel/sched/swait.c
index e1c655f92..f230b1ac7 100644
--- a/kernel/sched/swait.c
+++ b/kernel/sched/swait.c
@@ -64,6 +64,7 @@ void swake_up_all(struct swait_queue_head *q)
struct swait_queue *curr;
LIST_HEAD(tmp);
+ WARN_ON(irqs_disabled());
raw_spin_lock_irq(&q->lock);
list_splice_init(&q->task_list, &tmp);
while (!list_empty(&tmp)) {
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index 4bf575e4e..77f50c703 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -528,7 +528,8 @@ static int init_rootdomain(struct root_domain *rd)
#ifdef HAVE_RT_PUSH_IPI
rd->rto_cpu = -1;
raw_spin_lock_init(&rd->rto_lock);
- init_irq_work(&rd->rto_push_work, rto_push_irq_work_func);
+// init_irq_work(&rd->rto_push_work, rto_push_irq_work_func);
+ rd->rto_push_work = IRQ_WORK_INIT_HARD(rto_push_irq_work_func);
#endif
init_dl_bw(&rd->dl_bw);
diff --git a/kernel/signal.c b/kernel/signal.c
index eed7a3a38..9769b462e 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -20,6 +20,7 @@
#include <linux/sched/task.h>
#include <linux/sched/task_stack.h>
#include <linux/sched/cputime.h>
+#include <linux/sched/rt.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/proc_fs.h>
@@ -406,13 +407,30 @@ void task_join_group_stop(struct task_struct *task)
task_set_jobctl_pending(task, mask | JOBCTL_STOP_PENDING);
}
+static inline struct sigqueue *get_task_cache(struct task_struct *t)
+{
+ struct sigqueue *q = t->sigqueue_cache;
+
+ if (cmpxchg(&t->sigqueue_cache, q, NULL) != q)
+ return NULL;
+ return q;
+}
+
+static inline int put_task_cache(struct task_struct *t, struct sigqueue *q)
+{
+ if (cmpxchg(&t->sigqueue_cache, NULL, q) == NULL)
+ return 0;
+ return 1;
+}
+
/*
* allocate a new signal queue record
* - this may be called without locks if and only if t == current, otherwise an
* appropriate lock must be held to stop the target task from exiting
*/
static struct sigqueue *
-__sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimit)
+__sigqueue_do_alloc(int sig, struct task_struct *t, gfp_t flags,
+ int override_rlimit, int fromslab)
{
struct sigqueue *q = NULL;
struct user_struct *user;
@@ -434,7 +452,10 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimi
rcu_read_unlock();
if (override_rlimit || likely(sigpending <= task_rlimit(t, RLIMIT_SIGPENDING))) {
- q = kmem_cache_alloc(sigqueue_cachep, flags);
+ if (!fromslab)
+ q = get_task_cache(t);
+ if (!q)
+ q = kmem_cache_alloc(sigqueue_cachep, flags);
} else {
print_dropped_signal(sig);
}
@@ -451,6 +472,13 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimi
return q;
}
+static struct sigqueue *
+__sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags,
+ int override_rlimit)
+{
+ return __sigqueue_do_alloc(sig, t, flags, override_rlimit, 0);
+}
+
static void __sigqueue_free(struct sigqueue *q)
{
if (q->flags & SIGQUEUE_PREALLOC)
@@ -460,6 +488,21 @@ static void __sigqueue_free(struct sigqueue *q)
kmem_cache_free(sigqueue_cachep, q);
}
+static void sigqueue_free_current(struct sigqueue *q)
+{
+ struct user_struct *up;
+
+ if (q->flags & SIGQUEUE_PREALLOC)
+ return;
+
+ up = q->user;
+ if (rt_prio(current->normal_prio) && !put_task_cache(current, q)) {
+ if (atomic_dec_and_test(&up->sigpending))
+ free_uid(up);
+ } else
+ __sigqueue_free(q);
+}
+
void flush_sigqueue(struct sigpending *queue)
{
struct sigqueue *q;
@@ -472,6 +515,21 @@ void flush_sigqueue(struct sigpending *queue)
}
}
+/*
+ * Called from __exit_signal. Flush tsk->pending and
+ * tsk->sigqueue_cache
+ */
+void flush_task_sigqueue(struct task_struct *tsk)
+{
+ struct sigqueue *q;
+
+ flush_sigqueue(&tsk->pending);
+
+ q = get_task_cache(tsk);
+ if (q)
+ kmem_cache_free(sigqueue_cachep, q);
+}
+
/*
* Flush all pending signals for this kthread.
*/
@@ -596,7 +654,7 @@ still_pending:
(info->si_code == SI_TIMER) &&
(info->si_sys_private);
- __sigqueue_free(first);
+ sigqueue_free_current(first);
} else {
/*
* Ok, it wasn't in the queue. This must be
@@ -633,6 +691,8 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, kernel_siginfo_t *in
bool resched_timer = false;
int signr;
+ WARN_ON_ONCE(tsk != current);
+
/* We only dequeue private signals from ourselves, we don't let
* signalfd steal them
*/
@@ -1321,6 +1381,34 @@ force_sig_info_to_task(struct kernel_siginfo *info, struct task_struct *t)
struct k_sigaction *action;
int sig = info->si_signo;
+ /*
+ * On some archs, PREEMPT_RT has to delay sending a signal from a trap
+ * since it can not enable preemption, and the signal code's spin_locks
+ * turn into mutexes. Instead, it must set TIF_NOTIFY_RESUME which will
+ * send the signal on exit of the trap.
+ */
+#ifdef ARCH_RT_DELAYS_SIGNAL_SEND
+ if (in_atomic()) {
+ struct task_struct *t = current;
+
+ if (WARN_ON_ONCE(t->forced_info.si_signo))
+ return 0;
+
+ if (is_si_special(info)) {
+ WARN_ON_ONCE(info != SEND_SIG_PRIV);
+ t->forced_info.si_signo = info->si_signo;
+ t->forced_info.si_errno = 0;
+ t->forced_info.si_code = SI_KERNEL;
+ t->forced_info.si_pid = 0;
+ t->forced_info.si_uid = 0;
+ } else {
+ t->forced_info = *info;
+ }
+
+ set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
+ return 0;
+ }
+#endif
spin_lock_irqsave(&t->sighand->siglock, flags);
action = &t->sighand->action[sig-1];
ignored = action->sa.sa_handler == SIG_IGN;
@@ -1814,7 +1902,8 @@ EXPORT_SYMBOL(kill_pid);
*/
struct sigqueue *sigqueue_alloc(void)
{
- struct sigqueue *q = __sigqueue_alloc(-1, current, GFP_KERNEL, 0);
+ /* Preallocated sigqueue objects always from the slabcache ! */
+ struct sigqueue *q = __sigqueue_do_alloc(-1, current, GFP_KERNEL, 0, 1);
if (q)
q->flags |= SIGQUEUE_PREALLOC;
@@ -2200,16 +2289,8 @@ static void ptrace_stop(int exit_code, int why, int clear_code, kernel_siginfo_t
if (gstop_done && ptrace_reparented(current))
do_notify_parent_cldstop(current, false, why);
- /*
- * Don't want to allow preemption here, because
- * sys_ptrace() needs this task to be inactive.
- *
- * XXX: implement read_unlock_no_resched().
- */
- preempt_disable();
read_unlock(&tasklist_lock);
cgroup_enter_frozen();
- preempt_enable_no_resched();
freezable_schedule();
cgroup_leave_frozen(true);
} else {
diff --git a/kernel/smp.c b/kernel/smp.c
index d9ba6935f..cf034c161 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -488,8 +488,18 @@ void flush_smp_call_function_from_idle(void)
local_irq_save(flags);
flush_smp_call_function_queue(true);
- if (local_softirq_pending())
- do_softirq();
+
+ if (local_softirq_pending()) {
+
+ if (!IS_ENABLED(CONFIG_PREEMPT_RT)) {
+ do_softirq();
+ } else {
+ struct task_struct *ksoftirqd = this_cpu_ksoftirqd();
+
+ if (ksoftirqd && ksoftirqd->state != TASK_RUNNING)
+ wake_up_process(ksoftirqd);
+ }
+ }
local_irq_restore(flags);
}
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 4196b9f84..aebf2d468 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -13,6 +13,7 @@
#include <linux/kernel_stat.h>
#include <linux/interrupt.h>
#include <linux/init.h>
+#include <linux/local_lock.h>
#include <linux/mm.h>
#include <linux/notifier.h>
#include <linux/percpu.h>
@@ -25,6 +26,7 @@
#include <linux/smpboot.h>
#include <linux/tick.h>
#include <linux/irq.h>
+#include <linux/wait_bit.h>
#define CREATE_TRACE_POINTS
#include <trace/events/irq.h>
@@ -92,27 +94,212 @@ static bool ksoftirqd_running(unsigned long pending)
!__kthread_should_park(tsk);
}
+#ifdef CONFIG_TRACE_IRQFLAGS
+DEFINE_PER_CPU(int, hardirqs_enabled);
+DEFINE_PER_CPU(int, hardirq_context);
+EXPORT_PER_CPU_SYMBOL_GPL(hardirqs_enabled);
+EXPORT_PER_CPU_SYMBOL_GPL(hardirq_context);
+#endif
+
/*
- * preempt_count and SOFTIRQ_OFFSET usage:
- * - preempt_count is changed by SOFTIRQ_OFFSET on entering or leaving
- * softirq processing.
- * - preempt_count is changed by SOFTIRQ_DISABLE_OFFSET (= 2 * SOFTIRQ_OFFSET)
+ * SOFTIRQ_OFFSET usage:
+ *
+ * On !RT kernels 'count' is the preempt counter, on RT kernels this applies
+ * to a per CPU counter and to task::softirqs_disabled_cnt.
+ *
+ * - count is changed by SOFTIRQ_OFFSET on entering or leaving softirq
+ * processing.
+ *
+ * - count is changed by SOFTIRQ_DISABLE_OFFSET (= 2 * SOFTIRQ_OFFSET)
* on local_bh_disable or local_bh_enable.
+ *
* This lets us distinguish between whether we are currently processing
* softirq and whether we just have bh disabled.
*/
+#ifdef CONFIG_PREEMPT_RT
/*
- * This one is for softirq.c-internal use,
- * where hardirqs are disabled legitimately:
+ * RT accounts for BH disabled sections in task::softirqs_disabled_cnt and
+ * also in per CPU softirq_ctrl::cnt. This is necessary to allow tasks in a
+ * softirq disabled section to be preempted.
+ *
+ * The per task counter is used for softirq_count(), in_softirq() and
+ * in_serving_softirqs() because these counts are only valid when the task
+ * holding softirq_ctrl::lock is running.
+ *
+ * The per CPU counter prevents pointless wakeups of ksoftirqd in case that
+ * the task which is in a softirq disabled section is preempted or blocks.
*/
-#ifdef CONFIG_TRACE_IRQFLAGS
+struct softirq_ctrl {
+ local_lock_t lock;
+ int cnt;
+};
-DEFINE_PER_CPU(int, hardirqs_enabled);
-DEFINE_PER_CPU(int, hardirq_context);
-EXPORT_PER_CPU_SYMBOL_GPL(hardirqs_enabled);
-EXPORT_PER_CPU_SYMBOL_GPL(hardirq_context);
+static DEFINE_PER_CPU(struct softirq_ctrl, softirq_ctrl) = {
+ .lock = INIT_LOCAL_LOCK(softirq_ctrl.lock),
+};
+
+/**
+ * local_bh_blocked() - Check for idle whether BH processing is blocked
+ *
+ * Returns false if the per CPU softirq::cnt is 0 otherwise true.
+ *
+ * This is invoked from the idle task to guard against false positive
+ * softirq pending warnings, which would happen when the task which holds
+ * softirq_ctrl::lock was the only running task on the CPU and blocks on
+ * some other lock.
+ */
+bool local_bh_blocked(void)
+{
+ return __this_cpu_read(softirq_ctrl.cnt) != 0;
+}
+
+void __local_bh_disable_ip(unsigned long ip, unsigned int cnt)
+{
+ unsigned long flags;
+ int newcnt;
+
+ WARN_ON_ONCE(in_hardirq());
+
+ /* First entry of a task into a BH disabled section? */
+ if (!current->softirq_disable_cnt) {
+ if (preemptible()) {
+ local_lock(&softirq_ctrl.lock);
+ /* Required to meet the RCU bottomhalf requirements. */
+ rcu_read_lock();
+ } else {
+ DEBUG_LOCKS_WARN_ON(this_cpu_read(softirq_ctrl.cnt));
+ }
+ }
+
+ /*
+ * Track the per CPU softirq disabled state. On RT this is per CPU
+ * state to allow preemption of bottom half disabled sections.
+ */
+ newcnt = __this_cpu_add_return(softirq_ctrl.cnt, cnt);
+ /*
+ * Reflect the result in the task state to prevent recursion on the
+ * local lock and to make softirq_count() & al work.
+ */
+ current->softirq_disable_cnt = newcnt;
+
+ if (IS_ENABLED(CONFIG_TRACE_IRQFLAGS) && newcnt == cnt) {
+ raw_local_irq_save(flags);
+ lockdep_softirqs_off(ip);
+ raw_local_irq_restore(flags);
+ }
+}
+EXPORT_SYMBOL(__local_bh_disable_ip);
+
+static void __local_bh_enable(unsigned int cnt, bool unlock)
+{
+ unsigned long flags;
+ int newcnt;
+
+ DEBUG_LOCKS_WARN_ON(current->softirq_disable_cnt !=
+ this_cpu_read(softirq_ctrl.cnt));
+
+ if (IS_ENABLED(CONFIG_TRACE_IRQFLAGS) && softirq_count() == cnt) {
+ raw_local_irq_save(flags);
+ lockdep_softirqs_on(_RET_IP_);
+ raw_local_irq_restore(flags);
+ }
+
+ newcnt = __this_cpu_sub_return(softirq_ctrl.cnt, cnt);
+ current->softirq_disable_cnt = newcnt;
+
+ if (!newcnt && unlock) {
+ rcu_read_unlock();
+ local_unlock(&softirq_ctrl.lock);
+ }
+}
+
+void __local_bh_enable_ip(unsigned long ip, unsigned int cnt)
+{
+ bool preempt_on = preemptible();
+ unsigned long flags;
+ u32 pending;
+ int curcnt;
+
+ WARN_ON_ONCE(in_irq());
+ lockdep_assert_irqs_enabled();
+ local_irq_save(flags);
+ curcnt = __this_cpu_read(softirq_ctrl.cnt);
+
+ /*
+ * If this is not reenabling soft interrupts, no point in trying to
+ * run pending ones.
+ */
+ if (curcnt != cnt)
+ goto out;
+
+ pending = local_softirq_pending();
+ if (!pending || ksoftirqd_running(pending))
+ goto out;
+
+ /*
+ * If this was called from non preemptible context, wake up the
+ * softirq daemon.
+ */
+ if (!preempt_on) {
+ wakeup_softirqd();
+ goto out;
+ }
+
+ /*
+ * Adjust softirq count to SOFTIRQ_OFFSET which makes
+ * in_serving_softirq() become true.
+ */
+ cnt = SOFTIRQ_OFFSET;
+ __local_bh_enable(cnt, false);
+ __do_softirq();
+
+out:
+ __local_bh_enable(cnt, preempt_on);
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL(__local_bh_enable_ip);
+
+/*
+ * Invoked from ksoftirqd_run() outside of the interrupt disabled section
+ * to acquire the per CPU local lock for reentrancy protection.
+ */
+static inline void ksoftirqd_run_begin(void)
+{
+ __local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET);
+ local_irq_disable();
+}
+
+/* Counterpart to ksoftirqd_run_begin() */
+static inline void ksoftirqd_run_end(void)
+{
+ __local_bh_enable(SOFTIRQ_OFFSET, true);
+ WARN_ON_ONCE(in_interrupt());
+ local_irq_enable();
+}
+
+static inline void softirq_handle_begin(void) { }
+static inline void softirq_handle_end(void) { }
+
+static inline bool should_wake_ksoftirqd(void)
+{
+ return !this_cpu_read(softirq_ctrl.cnt);
+}
+
+static inline void invoke_softirq(void)
+{
+ if (should_wake_ksoftirqd())
+ wakeup_softirqd();
+}
+
+#else /* CONFIG_PREEMPT_RT */
+
+/*
+ * This one is for softirq.c-internal use, where hardirqs are disabled
+ * legitimately:
+ */
+#ifdef CONFIG_TRACE_IRQFLAGS
void __local_bh_disable_ip(unsigned long ip, unsigned int cnt)
{
unsigned long flags;
@@ -203,6 +390,78 @@ void __local_bh_enable_ip(unsigned long ip, unsigned int cnt)
}
EXPORT_SYMBOL(__local_bh_enable_ip);
+static inline void softirq_handle_begin(void)
+{
+ __local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET);
+}
+
+static inline void softirq_handle_end(void)
+{
+ __local_bh_enable(SOFTIRQ_OFFSET);
+ WARN_ON_ONCE(in_interrupt());
+}
+
+static inline void ksoftirqd_run_begin(void)
+{
+ local_irq_disable();
+}
+
+static inline void ksoftirqd_run_end(void)
+{
+ local_irq_enable();
+}
+
+static inline bool should_wake_ksoftirqd(void)
+{
+ return true;
+}
+
+static inline void invoke_softirq(void)
+{
+ if (ksoftirqd_running(local_softirq_pending()))
+ return;
+
+ if (!force_irqthreads) {
+#ifdef CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK
+ /*
+ * We can safely execute softirq on the current stack if
+ * it is the irq stack, because it should be near empty
+ * at this stage.
+ */
+ __do_softirq();
+#else
+ /*
+ * Otherwise, irq_exit() is called on the task stack that can
+ * be potentially deep already. So call softirq in its own stack
+ * to prevent from any overrun.
+ */
+ do_softirq_own_stack();
+#endif
+ } else {
+ wakeup_softirqd();
+ }
+}
+
+asmlinkage __visible void do_softirq(void)
+{
+ __u32 pending;
+ unsigned long flags;
+
+ if (in_interrupt())
+ return;
+
+ local_irq_save(flags);
+
+ pending = local_softirq_pending();
+
+ if (pending && !ksoftirqd_running(pending))
+ do_softirq_own_stack();
+
+ local_irq_restore(flags);
+}
+
+#endif /* !CONFIG_PREEMPT_RT */
+
/*
* We restart softirq processing for at most MAX_SOFTIRQ_RESTART times,
* but break the loop if need_resched() is set or after 2 ms.
@@ -270,10 +529,10 @@ asmlinkage __visible void __softirq_entry __do_softirq(void)
current->flags &= ~PF_MEMALLOC;
pending = local_softirq_pending();
- account_irq_enter_time(current);
- __local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET);
+ softirq_handle_begin();
in_hardirq = lockdep_softirq_start();
+ account_softirq_enter(current);
restart:
/* Reset the pending bitmask before enabling irqs */
@@ -307,8 +566,10 @@ restart:
pending >>= softirq_bit;
}
- if (__this_cpu_read(ksoftirqd) == current)
+ if (!IS_ENABLED(CONFIG_PREEMPT_RT) &&
+ __this_cpu_read(ksoftirqd) == current)
rcu_softirq_qs();
+
local_irq_disable();
pending = local_softirq_pending();
@@ -320,29 +581,10 @@ restart:
wakeup_softirqd();
}
- lockdep_softirq_end(in_hardirq);
- account_irq_exit_time(current);
- __local_bh_enable(SOFTIRQ_OFFSET);
- WARN_ON_ONCE(in_interrupt());
- current_restore_flags(old_flags, PF_MEMALLOC);
-}
-
-asmlinkage __visible void do_softirq(void)
-{
- __u32 pending;
- unsigned long flags;
-
- if (in_interrupt())
- return;
-
- local_irq_save(flags);
-
- pending = local_softirq_pending();
-
- if (pending && !ksoftirqd_running(pending))
- do_softirq_own_stack();
-
- local_irq_restore(flags);
+ account_softirq_exit(current);
+ lockdep_softirq_end(in_hardirq);
+ softirq_handle_end();
+ current_restore_flags(old_flags, PF_MEMALLOC);
}
/**
@@ -350,17 +592,12 @@ asmlinkage __visible void do_softirq(void)
*/
void irq_enter_rcu(void)
{
- if (tick_nohz_full_cpu(smp_processor_id()) ||
- (is_idle_task(current) && !in_interrupt())) {
- /*
- * Prevent raise_softirq from needlessly waking up ksoftirqd
- * here, as softirq will be serviced on return from interrupt.
- */
- local_bh_disable();
+ __irq_enter_raw();
+
+ if (is_idle_task(current) && (irq_count() == HARDIRQ_OFFSET))
tick_irq_enter();
- _local_bh_enable();
- }
- __irq_enter();
+
+ account_hardirq_enter(current);
}
/**
@@ -372,31 +609,7 @@ void irq_enter(void)
irq_enter_rcu();
}
-static inline void invoke_softirq(void)
-{
- if (ksoftirqd_running(local_softirq_pending()))
- return;
- if (!force_irqthreads || !__this_cpu_read(ksoftirqd)) {
-#ifdef CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK
- /*
- * We can safely execute softirq on the current stack if
- * it is the irq stack, because it should be near empty
- * at this stage.
- */
- __do_softirq();
-#else
- /*
- * Otherwise, irq_exit() is called on the task stack that can
- * be potentially deep already. So call softirq in its own stack
- * to prevent from any overrun.
- */
- do_softirq_own_stack();
-#endif
- } else {
- wakeup_softirqd();
- }
-}
static inline void tick_irq_exit(void)
{
@@ -418,7 +631,7 @@ static inline void __irq_exit_rcu(void)
#else
lockdep_assert_irqs_disabled();
#endif
- account_irq_exit_time(current);
+ account_hardirq_exit(current);
preempt_count_sub(HARDIRQ_OFFSET);
if (!in_interrupt() && local_softirq_pending())
invoke_softirq();
@@ -467,7 +680,7 @@ inline void raise_softirq_irqoff(unsigned int nr)
* Otherwise we wake up ksoftirqd to make sure we
* schedule the softirq soon.
*/
- if (!in_interrupt())
+ if (!in_interrupt() && should_wake_ksoftirqd())
wakeup_softirqd();
}
@@ -533,6 +746,16 @@ void __tasklet_hi_schedule(struct tasklet_struct *t)
}
EXPORT_SYMBOL(__tasklet_hi_schedule);
+static inline bool tasklet_clear_sched(struct tasklet_struct *t)
+{
+ if (test_and_clear_bit(TASKLET_STATE_SCHED, &t->state)) {
+ wake_up_var(&t->state);
+ return true;
+ }
+
+ return false;
+}
+
static void tasklet_action_common(struct softirq_action *a,
struct tasklet_head *tl_head,
unsigned int softirq_nr)
@@ -552,8 +775,7 @@ static void tasklet_action_common(struct softirq_action *a,
if (tasklet_trylock(t)) {
if (!atomic_read(&t->count)) {
- if (!test_and_clear_bit(TASKLET_STATE_SCHED,
- &t->state))
+ if (!tasklet_clear_sched(t))
BUG();
if (t->use_callback)
t->callback(t);
@@ -608,21 +830,62 @@ void tasklet_init(struct tasklet_struct *t,
}
EXPORT_SYMBOL(tasklet_init);
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT)
+/*
+ * Do not use in new code. Waiting for tasklets from atomic contexts is
+ * error prone and should be avoided.
+ */
+void tasklet_unlock_spin_wait(struct tasklet_struct *t)
+{
+ while (test_bit(TASKLET_STATE_RUN, &(t)->state)) {
+ if (IS_ENABLED(CONFIG_PREEMPT_RT)) {
+ /*
+ * Prevent a live lock when current preempted soft
+ * interrupt processing or prevents ksoftirqd from
+ * running. If the tasklet runs on a different CPU
+ * then this has no effect other than doing the BH
+ * disable/enable dance for nothing.
+ */
+ local_bh_disable();
+ local_bh_enable();
+ } else {
+ cpu_relax();
+ }
+ }
+}
+EXPORT_SYMBOL(tasklet_unlock_spin_wait);
+#endif
+
void tasklet_kill(struct tasklet_struct *t)
{
if (in_interrupt())
pr_notice("Attempt to kill tasklet from interrupt\n");
- while (test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) {
- do {
- yield();
- } while (test_bit(TASKLET_STATE_SCHED, &t->state));
- }
+ while (test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
+ wait_var_event(&t->state, !test_bit(TASKLET_STATE_SCHED, &t->state));
+
tasklet_unlock_wait(t);
- clear_bit(TASKLET_STATE_SCHED, &t->state);
+ tasklet_clear_sched(t);
}
EXPORT_SYMBOL(tasklet_kill);
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT)
+void tasklet_unlock(struct tasklet_struct *t)
+{
+ smp_mb__before_atomic();
+ clear_bit(TASKLET_STATE_RUN, &t->state);
+ smp_mb__after_atomic();
+ wake_up_var(&t->state);
+}
+EXPORT_SYMBOL_GPL(tasklet_unlock);
+
+void tasklet_unlock_wait(struct tasklet_struct *t)
+{
+ wait_var_event(&t->state, !test_bit(TASKLET_STATE_RUN, &t->state));
+}
+EXPORT_SYMBOL_GPL(tasklet_unlock_wait);
+#endif
+
void __init softirq_init(void)
{
int cpu;
@@ -645,18 +908,18 @@ static int ksoftirqd_should_run(unsigned int cpu)
static void run_ksoftirqd(unsigned int cpu)
{
- local_irq_disable();
+ ksoftirqd_run_begin();
if (local_softirq_pending()) {
/*
* We can safely run softirq on inline stack, as we are not deep
* in the task stack here.
*/
__do_softirq();
- local_irq_enable();
+ ksoftirqd_run_end();
cond_resched();
return;
}
- local_irq_enable();
+ ksoftirqd_run_end();
}
#ifdef CONFIG_HOTPLUG_CPU
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index d0bf6da49..7a74b501a 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -47,11 +47,27 @@ struct cpu_stopper {
struct list_head works; /* list of pending works */
struct cpu_stop_work stop_work; /* for stop_cpus */
+ unsigned long caller;
+ cpu_stop_fn_t fn;
};
static DEFINE_PER_CPU(struct cpu_stopper, cpu_stopper);
static bool stop_machine_initialized = false;
+void print_stop_info(const char *log_lvl, struct task_struct *task)
+{
+ /*
+ * If @task is a stopper task, it cannot migrate and task_cpu() is
+ * stable.
+ */
+ struct cpu_stopper *stopper = per_cpu_ptr(&cpu_stopper, task_cpu(task));
+
+ if (task != stopper->thread)
+ return;
+
+ printk("%sStopper: %pS <- %pS\n", log_lvl, stopper->fn, (void *)stopper->caller);
+}
+
/* static data for stop_cpus */
static DEFINE_MUTEX(stop_cpus_mutex);
static bool stop_cpus_in_progress;
@@ -128,7 +144,7 @@ static bool cpu_stop_queue_work(unsigned int cpu, struct cpu_stop_work *work)
int stop_one_cpu(unsigned int cpu, cpu_stop_fn_t fn, void *arg)
{
struct cpu_stop_done done;
- struct cpu_stop_work work = { .fn = fn, .arg = arg, .done = &done };
+ struct cpu_stop_work work = { .fn = fn, .arg = arg, .done = &done, .caller = _RET_IP_ };
cpu_stop_init_done(&done, 1);
if (!cpu_stop_queue_work(cpu, &work))
@@ -344,7 +360,8 @@ int stop_two_cpus(unsigned int cpu1, unsigned int cpu2, cpu_stop_fn_t fn, void *
work1 = work2 = (struct cpu_stop_work){
.fn = multi_cpu_stop,
.arg = &msdata,
- .done = &done
+ .done = &done,
+ .caller = _RET_IP_,
};
cpu_stop_init_done(&done, 2);
@@ -380,7 +397,7 @@ int stop_two_cpus(unsigned int cpu1, unsigned int cpu2, cpu_stop_fn_t fn, void *
bool stop_one_cpu_nowait(unsigned int cpu, cpu_stop_fn_t fn, void *arg,
struct cpu_stop_work *work_buf)
{
- *work_buf = (struct cpu_stop_work){ .fn = fn, .arg = arg, };
+ *work_buf = (struct cpu_stop_work){ .fn = fn, .arg = arg, .caller = _RET_IP_, };
return cpu_stop_queue_work(cpu, work_buf);
}
@@ -500,6 +517,8 @@ repeat:
int ret;
/* cpu stop callbacks must not sleep, make in_atomic() == T */
+ stopper->caller = work->caller;
+ stopper->fn = fn;
preempt_count_inc();
ret = fn(arg);
if (done) {
@@ -508,6 +527,8 @@ repeat:
cpu_stop_signal_done(done);
}
preempt_count_dec();
+ stopper->fn = NULL;
+ stopper->caller = 0;
WARN_ONCE(preempt_count(),
"cpu_stop: %ps(%p) leaked preempt count\n", fn, arg);
goto repeat;
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 0aebb88f1..7bc5b47cd 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -2054,6 +2054,36 @@ SYSCALL_DEFINE2(nanosleep_time32, struct old_timespec32 __user *, rqtp,
}
#endif
+#ifdef CONFIG_PREEMPT_RT
+/*
+ * Sleep for 1 ms in hope whoever holds what we want will let it go.
+ */
+void cpu_chill(void)
+{
+ unsigned int freeze_flag = current->flags & PF_NOFREEZE;
+ struct task_struct *self = current;
+ ktime_t chill_time;
+
+ raw_spin_lock_irq(&self->pi_lock);
+ self->saved_state = self->state;
+ __set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+ raw_spin_unlock_irq(&self->pi_lock);
+
+ chill_time = ktime_set(0, NSEC_PER_MSEC);
+
+ current->flags |= PF_NOFREEZE;
+ schedule_hrtimeout(&chill_time, HRTIMER_MODE_REL_HARD);
+ if (!freeze_flag)
+ current->flags &= ~PF_NOFREEZE;
+
+ raw_spin_lock_irq(&self->pi_lock);
+ __set_current_state_no_track(self->saved_state);
+ self->saved_state = TASK_RUNNING;
+ raw_spin_unlock_irq(&self->pi_lock);
+}
+EXPORT_SYMBOL(cpu_chill);
+#endif
+
/*
* Functions related to boot-time initialization:
*/
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index d6dcce984..1a98eca9e 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -1031,7 +1031,7 @@ static bool can_stop_idle_tick(int cpu, struct tick_sched *ts)
if (unlikely(local_softirq_pending())) {
static int ratelimit;
- if (ratelimit < 10 &&
+ if (ratelimit < 10 && !local_bh_blocked() &&
(local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK)) {
pr_warn("NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #%02x!!!\n",
(unsigned int) local_softirq_pending());
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index c1b52dab3..101a73eea 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -1454,7 +1454,7 @@ static void del_timer_wait_running(struct timer_list *timer)
u32 tf;
tf = READ_ONCE(timer->flags);
- if (!(tf & TIMER_MIGRATING)) {
+ if (!(tf & (TIMER_MIGRATING | TIMER_IRQSAFE))) {
struct timer_base *base = get_timer_base(tf);
/*
@@ -1522,6 +1522,12 @@ static int __timer_delete_sync(struct timer_list *timer, bool shutdown)
* could lead to deadlock.
*/
WARN_ON(in_irq() && !(timer->flags & TIMER_IRQSAFE));
+ /*
+ * Must be able to sleep on PREEMPT_RT because of the slowpath in
+ * del_timer_wait_running().
+ */
+ if (IS_ENABLED(CONFIG_PREEMPT_RT) && !(timer->flags & TIMER_IRQSAFE))
+ lockdep_assert_preemption_enabled();
do {
ret = __try_to_del_timer_sync(timer, shutdown);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index a470950b8..5d90301ad 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2603,60 +2603,43 @@ enum print_line_t trace_handle_return(struct trace_seq *s)
}
EXPORT_SYMBOL_GPL(trace_handle_return);
-unsigned int tracing_gen_ctx_flags(unsigned long irqflags)
+static unsigned short migration_disable_value(void)
{
- unsigned int trace_flags = 0;
+#if defined(CONFIG_SMP) && defined(CONFIG_PREEMPT_RT)
+ return current->migration_disabled;
+#else
+ return 0;
+#endif
+}
+
+unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status)
+{
+ unsigned int trace_flags = irqs_status;
unsigned int pc;
pc = preempt_count();
-#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
- if (irqs_disabled_flags(irqflags))
- trace_flags |= TRACE_FLAG_IRQS_OFF;
-#else
- trace_flags |= TRACE_FLAG_IRQS_NOSUPPORT;
-#endif
-
if (pc & NMI_MASK)
trace_flags |= TRACE_FLAG_NMI;
if (pc & HARDIRQ_MASK)
trace_flags |= TRACE_FLAG_HARDIRQ;
-
- if (pc & SOFTIRQ_OFFSET)
+ if (in_serving_softirq())
trace_flags |= TRACE_FLAG_SOFTIRQ;
if (tif_need_resched())
trace_flags |= TRACE_FLAG_NEED_RESCHED;
if (test_preempt_need_resched())
trace_flags |= TRACE_FLAG_PREEMPT_RESCHED;
- return (trace_flags << 16) | (pc & 0xff);
-}
-unsigned int tracing_gen_ctx(void)
-{
- unsigned long irqflags;
-
-#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
- local_save_flags(irqflags);
-#else
- irqflags = 0;
+#ifdef CONFIG_PREEMPT_LAZY
+ if (need_resched_lazy())
+ trace_flags |= TRACE_FLAG_NEED_RESCHED_LAZY;
#endif
- return tracing_gen_ctx_flags(irqflags);
-}
-unsigned int tracing_gen_ctx_dec(void)
-{
- unsigned int trace_ctx;
-
- trace_ctx = tracing_gen_ctx();
-
- /*
- * Subtract one from the preeption counter if preemption is enabled,
- * see trace_event_buffer_reserve()for details.
- */
- if (IS_ENABLED(CONFIG_PREEMPTION))
- trace_ctx--;
- return trace_ctx;
+ return (pc & 0xff) |
+ (migration_disable_value() & 0xff) << 8 |
+ (preempt_lazy_count() & 0xff) << 16 |
+ (trace_flags << 24);
}
struct ring_buffer_event *
@@ -3858,14 +3841,17 @@ unsigned long trace_total_entries(struct trace_array *tr)
static void print_lat_help_header(struct seq_file *m)
{
- seq_puts(m, "# _------=> CPU# \n"
- "# / _-----=> irqs-off \n"
- "# | / _----=> need-resched \n"
- "# || / _---=> hardirq/softirq \n"
- "# ||| / _--=> preempt-depth \n"
- "# |||| / delay \n"
- "# cmd pid ||||| time | caller \n"
- "# \\ / ||||| \\ | / \n");
+ seq_puts(m, "# _--------=> CPU# \n"
+ "# / _-------=> irqs-off \n"
+ "# | / _------=> need-resched \n"
+ "# || / _-----=> need-resched-lazy\n"
+ "# ||| / _----=> hardirq/softirq \n"
+ "# |||| / _---=> preempt-depth \n"
+ "# ||||| / _--=> preempt-lazy-depth\n"
+ "# |||||| / _-=> migrate-disable \n"
+ "# ||||||| / delay \n"
+ "# cmd pid |||||||| time | caller \n"
+ "# \\ / |||||||| \\ | / \n");
}
static void print_event_info(struct array_buffer *buf, struct seq_file *m)
@@ -3899,13 +3885,16 @@ static void print_func_help_header_irq(struct array_buffer *buf, struct seq_file
print_event_info(buf, m);
- seq_printf(m, "# %.*s _-----=> irqs-off\n", prec, space);
- seq_printf(m, "# %.*s / _----=> need-resched\n", prec, space);
- seq_printf(m, "# %.*s| / _---=> hardirq/softirq\n", prec, space);
- seq_printf(m, "# %.*s|| / _--=> preempt-depth\n", prec, space);
- seq_printf(m, "# %.*s||| / delay\n", prec, space);
- seq_printf(m, "# TASK-PID %.*s CPU# |||| TIMESTAMP FUNCTION\n", prec, " TGID ");
- seq_printf(m, "# | | %.*s | |||| | |\n", prec, " | ");
+ seq_printf(m, "# %.*s _-------=> irqs-off\n", prec, space);
+ seq_printf(m, "# %.*s / _------=> need-resched\n", prec, space);
+ seq_printf(m, "# %.*s| / _-----=> need-resched-lazy\n", prec, space);
+ seq_printf(m, "# %.*s|| / _----=> hardirq/softirq\n", prec, space);
+ seq_printf(m, "# %.*s||| / _---=> preempt-depth\n", prec, space);
+ seq_printf(m, "# %.*s|||| / _--=> preempt-lazy-depth\n", prec, space);
+ seq_printf(m, "# %.*s||||| / _-=> migrate-disable\n", prec, space);
+ seq_printf(m, "# %.*s|||||| / delay\n", prec, space);
+ seq_printf(m, "# TASK-PID %.*s CPU# ||||||| TIMESTAMP FUNCTION\n", prec, " TGID ");
+ seq_printf(m, "# | | %.*s | ||||||| | |\n", prec, " | ");
}
void
@@ -9556,7 +9545,6 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
tracing_off();
local_irq_save(flags);
- printk_nmi_direct_enter();
/* Simulate the iterator */
trace_init_global_iter(&iter);
@@ -9636,7 +9624,6 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
atomic_dec(&per_cpu_ptr(iter.array_buffer->data, cpu)->disabled);
}
atomic_dec(&dump_running);
- printk_nmi_direct_exit();
local_irq_restore(flags);
}
EXPORT_SYMBOL_GPL(ftrace_dump);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index ae3411a6c..987fe88b5 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -141,25 +141,6 @@ struct kretprobe_trace_entry_head {
unsigned long ret_ip;
};
-/*
- * trace_flag_type is an enumeration that holds different
- * states when a trace occurs. These are:
- * IRQS_OFF - interrupts were disabled
- * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
- * NEED_RESCHED - reschedule is requested
- * HARDIRQ - inside an interrupt handler
- * SOFTIRQ - inside a softirq handler
- */
-enum trace_flag_type {
- TRACE_FLAG_IRQS_OFF = 0x01,
- TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
- TRACE_FLAG_NEED_RESCHED = 0x04,
- TRACE_FLAG_HARDIRQ = 0x08,
- TRACE_FLAG_SOFTIRQ = 0x10,
- TRACE_FLAG_PREEMPT_RESCHED = 0x20,
- TRACE_FLAG_NMI = 0x40,
-};
-
#define TRACE_BUF_SIZE 1024
struct trace_array;
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index c9ee8b730..8f98de8da 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -184,6 +184,8 @@ static int trace_define_common_fields(void)
__common_field(unsigned char, flags);
__common_field(unsigned char, preempt_count);
__common_field(int, pid);
+ __common_field(unsigned char, migrate_disable);
+ __common_field(unsigned char, preempt_lazy_count);
return ret;
}
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 74adb873e..995a4caf4 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -441,6 +441,7 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
{
char hardsoft_irq;
char need_resched;
+ char need_resched_lazy;
char irqs_off;
int hardirq;
int softirq;
@@ -471,6 +472,9 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
break;
}
+ need_resched_lazy =
+ (entry->flags & TRACE_FLAG_NEED_RESCHED_LAZY) ? 'L' : '.';
+
hardsoft_irq =
(nmi && hardirq) ? 'Z' :
nmi ? 'z' :
@@ -479,14 +483,25 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
softirq ? 's' :
'.' ;
- trace_seq_printf(s, "%c%c%c",
- irqs_off, need_resched, hardsoft_irq);
+ trace_seq_printf(s, "%c%c%c%c",
+ irqs_off, need_resched, need_resched_lazy,
+ hardsoft_irq);
if (entry->preempt_count)
trace_seq_printf(s, "%x", entry->preempt_count);
else
trace_seq_putc(s, '.');
+ if (entry->preempt_lazy_count)
+ trace_seq_printf(s, "%x", entry->preempt_lazy_count);
+ else
+ trace_seq_putc(s, '.');
+
+ if (entry->migrate_disable)
+ trace_seq_printf(s, "%x", entry->migrate_disable);
+ else
+ trace_seq_putc(s, '.');
+
return !trace_seq_has_overflowed(s);
}
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 687c4e61d..b3eda5091 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4859,9 +4859,7 @@ void show_workqueue_state(void)
* drivers that queue work while holding locks
* also taken in their write paths.
*/
- printk_safe_enter();
show_pwq(pwq);
- printk_safe_exit();
}
raw_spin_unlock_irqrestore(&pwq->pool->lock, flags);
/*
@@ -4891,7 +4889,6 @@ void show_workqueue_state(void)
* queue work while holding locks also taken in their write
* paths.
*/
- printk_safe_enter();
pr_info("pool %d:", pool->id);
pr_cont_pool_info(pool);
pr_cont(" hung=%lus workers=%d", hung, pool->nr_workers);
@@ -4904,7 +4901,6 @@ void show_workqueue_state(void)
first = false;
}
pr_cont("\n");
- printk_safe_exit();
next_pool:
raw_spin_unlock_irqrestore(&pool->lock, flags);
/*
@@ -4996,6 +4992,10 @@ static void unbind_workers(int cpu)
pool->flags |= POOL_DISASSOCIATED;
raw_spin_unlock_irq(&pool->lock);
+
+ for_each_pool_worker(worker, pool)
+ WARN_ON_ONCE(set_cpus_allowed_ptr(worker->task, cpu_active_mask) < 0);
+
mutex_unlock(&wq_pool_attach_mutex);
/*
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index d7ba1cde5..077a1b275 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1423,7 +1423,7 @@ config DEBUG_ATOMIC_SLEEP
config DEBUG_LOCKING_API_SELFTESTS
bool "Locking API boot-time self-tests"
- depends on DEBUG_KERNEL
+ depends on DEBUG_KERNEL && !PREEMPT_RT
help
Say Y here if you want the kernel to run a short self-test during
bootup. The self-test checks whether common types of locking bugs
diff --git a/lib/bug.c b/lib/bug.c
index 4ab398a2d..9c681f29e 100644
--- a/lib/bug.c
+++ b/lib/bug.c
@@ -202,6 +202,7 @@ enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs)
else
pr_crit("Kernel BUG at %pB [verbose debug info unavailable]\n",
(void *)bugaddr);
+ pr_flush(1000, true);
return BUG_TRAP_TYPE_BUG;
}
diff --git a/lib/cpumask.c b/lib/cpumask.c
index fb22fb266..c3c76b833 100644
--- a/lib/cpumask.c
+++ b/lib/cpumask.c
@@ -261,3 +261,21 @@ int cpumask_any_and_distribute(const struct cpumask *src1p,
return next;
}
EXPORT_SYMBOL(cpumask_any_and_distribute);
+
+int cpumask_any_distribute(const struct cpumask *srcp)
+{
+ int next, prev;
+
+ /* NOTE: our first selection will skip 0. */
+ prev = __this_cpu_read(distribute_cpu_mask_prev);
+
+ next = cpumask_next(prev, srcp);
+ if (next >= nr_cpu_ids)
+ next = cpumask_first(srcp);
+
+ if (next < nr_cpu_ids)
+ __this_cpu_write(distribute_cpu_mask_prev, next);
+
+ return next;
+}
+EXPORT_SYMBOL(cpumask_any_distribute);
diff --git a/lib/debugobjects.c b/lib/debugobjects.c
index b055741a5..1a7594541 100644
--- a/lib/debugobjects.c
+++ b/lib/debugobjects.c
@@ -615,7 +615,9 @@ __debug_object_init(void *addr, const struct debug_obj_descr *descr, int onstack
struct debug_obj *obj, o;
struct debug_bucket *db;
unsigned long flags;
-
+#ifdef CONFIG_PREEMPT_RT
+ if (preempt_count() == 0 && !irqs_disabled())
+#endif
debug_objects_fill_pool();
db = get_bucket((unsigned long) addr);
diff --git a/lib/dump_stack.c b/lib/dump_stack.c
index a00ee6eed..f5a33b6f7 100644
--- a/lib/dump_stack.c
+++ b/lib/dump_stack.c
@@ -12,6 +12,7 @@
#include <linux/atomic.h>
#include <linux/kexec.h>
#include <linux/utsname.h>
+#include <linux/stop_machine.h>
static char dump_stack_arch_desc_str[128];
@@ -57,6 +58,7 @@ void dump_stack_print_info(const char *log_lvl)
log_lvl, dump_stack_arch_desc_str);
print_worker_info(log_lvl, current);
+ print_stop_info(log_lvl, current);
}
/**
diff --git a/lib/irq_poll.c b/lib/irq_poll.c
index 2f17b488d..7557bf7ec 100644
--- a/lib/irq_poll.c
+++ b/lib/irq_poll.c
@@ -37,6 +37,7 @@ void irq_poll_sched(struct irq_poll *iop)
list_add_tail(&iop->list, this_cpu_ptr(&blk_cpu_iopoll));
raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
local_irq_restore(flags);
+ preempt_check_resched_rt();
}
EXPORT_SYMBOL(irq_poll_sched);
@@ -72,6 +73,7 @@ void irq_poll_complete(struct irq_poll *iop)
local_irq_save(flags);
__irq_poll_complete(iop);
local_irq_restore(flags);
+ preempt_check_resched_rt();
}
EXPORT_SYMBOL(irq_poll_complete);
@@ -96,6 +98,7 @@ static void __latent_entropy irq_poll_softirq(struct softirq_action *h)
}
local_irq_enable();
+ preempt_check_resched_rt();
/* Even though interrupts have been re-enabled, this
* access is safe because interrupts can only add new
@@ -133,6 +136,7 @@ static void __latent_entropy irq_poll_softirq(struct softirq_action *h)
__raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
local_irq_enable();
+ preempt_check_resched_rt();
}
/**
@@ -196,6 +200,7 @@ static int irq_poll_cpu_dead(unsigned int cpu)
this_cpu_ptr(&blk_cpu_iopoll));
__raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
local_irq_enable();
+ preempt_check_resched_rt();
return 0;
}
diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c
index 76c52b0b7..98c376b02 100644
--- a/lib/locking-selftest.c
+++ b/lib/locking-selftest.c
@@ -787,6 +787,8 @@ GENERATE_TESTCASE(init_held_rtmutex);
#include "locking-selftest-spin-hardirq.h"
GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_spin)
+#ifndef CONFIG_PREEMPT_RT
+
#include "locking-selftest-rlock-hardirq.h"
GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_rlock)
@@ -802,9 +804,12 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_rlock)
#include "locking-selftest-wlock-softirq.h"
GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_wlock)
+#endif
+
#undef E1
#undef E2
+#ifndef CONFIG_PREEMPT_RT
/*
* Enabling hardirqs with a softirq-safe lock held:
*/
@@ -837,6 +842,8 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock)
#undef E1
#undef E2
+#endif
+
/*
* Enabling irqs with an irq-safe lock held:
*/
@@ -860,6 +867,8 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock)
#include "locking-selftest-spin-hardirq.h"
GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_spin)
+#ifndef CONFIG_PREEMPT_RT
+
#include "locking-selftest-rlock-hardirq.h"
GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_rlock)
@@ -875,6 +884,8 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_rlock)
#include "locking-selftest-wlock-softirq.h"
GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock)
+#endif
+
#undef E1
#undef E2
@@ -906,6 +917,8 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock)
#include "locking-selftest-spin-hardirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_spin)
+#ifndef CONFIG_PREEMPT_RT
+
#include "locking-selftest-rlock-hardirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_rlock)
@@ -921,6 +934,8 @@ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_rlock)
#include "locking-selftest-wlock-softirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock)
+#endif
+
#undef E1
#undef E2
#undef E3
@@ -954,6 +969,8 @@ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock)
#include "locking-selftest-spin-hardirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_spin)
+#ifndef CONFIG_PREEMPT_RT
+
#include "locking-selftest-rlock-hardirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_rlock)
@@ -969,10 +986,14 @@ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_rlock)
#include "locking-selftest-wlock-softirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_wlock)
+#endif
+
#undef E1
#undef E2
#undef E3
+#ifndef CONFIG_PREEMPT_RT
+
/*
* read-lock / write-lock irq inversion.
*
@@ -1162,6 +1183,11 @@ GENERATE_PERMUTATIONS_3_EVENTS(W1W2_R2R3_R3W1)
#undef E1
#undef E2
#undef E3
+
+#endif
+
+#ifndef CONFIG_PREEMPT_RT
+
/*
* read-lock / write-lock recursion that is actually safe.
*/
@@ -1208,6 +1234,8 @@ GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft_wlock)
#undef E2
#undef E3
+#endif
+
/*
* read-lock / write-lock recursion that is unsafe.
*/
@@ -2456,6 +2484,7 @@ void locking_selftest(void)
printk(" --------------------------------------------------------------------------\n");
+#ifndef CONFIG_PREEMPT_RT
/*
* irq-context testcases:
*/
@@ -2470,6 +2499,28 @@ void locking_selftest(void)
DO_TESTCASE_6x2x2RW("irq read-recursion #2", irq_read_recursion2);
DO_TESTCASE_6x2x2RW("irq read-recursion #3", irq_read_recursion3);
+#else
+ /* On -rt, we only do hardirq context test for raw spinlock */
+ DO_TESTCASE_1B("hard-irqs-on + irq-safe-A", irqsafe1_hard_spin, 12);
+ DO_TESTCASE_1B("hard-irqs-on + irq-safe-A", irqsafe1_hard_spin, 21);
+
+ DO_TESTCASE_1B("hard-safe-A + irqs-on", irqsafe2B_hard_spin, 12);
+ DO_TESTCASE_1B("hard-safe-A + irqs-on", irqsafe2B_hard_spin, 21);
+
+ DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 123);
+ DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 132);
+ DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 213);
+ DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 231);
+ DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 312);
+ DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 321);
+
+ DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 123);
+ DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 132);
+ DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 213);
+ DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 231);
+ DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 312);
+ DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 321);
+#endif
ww_tests();
force_read_lock_recursive = 0;
diff --git a/lib/nmi_backtrace.c b/lib/nmi_backtrace.c
index 8abe1870d..b09a490f5 100644
--- a/lib/nmi_backtrace.c
+++ b/lib/nmi_backtrace.c
@@ -75,12 +75,6 @@ void nmi_trigger_cpumask_backtrace(const cpumask_t *mask,
touch_softlockup_watchdog();
}
- /*
- * Force flush any remote buffers that might be stuck in IRQ context
- * and therefore could not run their irq_work.
- */
- printk_safe_flush();
-
clear_bit_unlock(0, &backtrace_flag);
put_cpu();
}
diff --git a/lib/scatterlist.c b/lib/scatterlist.c
index a59778946..907f59045 100644
--- a/lib/scatterlist.c
+++ b/lib/scatterlist.c
@@ -892,7 +892,7 @@ void sg_miter_stop(struct sg_mapping_iter *miter)
flush_kernel_dcache_page(miter->page);
if (miter->__flags & SG_MITER_ATOMIC) {
- WARN_ON_ONCE(preemptible());
+ WARN_ON_ONCE(!pagefault_disabled());
kunmap_atomic(miter->addr);
} else
kunmap(miter->page);
diff --git a/lib/smp_processor_id.c b/lib/smp_processor_id.c
index 2916606a9..0c0c42b14 100644
--- a/lib/smp_processor_id.c
+++ b/lib/smp_processor_id.c
@@ -26,6 +26,11 @@ unsigned int check_preemption_disabled(const char *what1, const char *what2)
if (current->nr_cpus_allowed == 1)
goto out;
+#ifdef CONFIG_SMP
+ if (current->migration_disabled)
+ goto out;
+#endif
+
/*
* It is valid to assume CPU-locality during early bootup:
*/
diff --git a/lib/test_lockup.c b/lib/test_lockup.c
index 78a630bbd..d27a80502 100644
--- a/lib/test_lockup.c
+++ b/lib/test_lockup.c
@@ -485,6 +485,21 @@ static int __init test_lockup_init(void)
return -EINVAL;
#ifdef CONFIG_DEBUG_SPINLOCK
+#ifdef CONFIG_PREEMPT_RT
+ if (test_magic(lock_spinlock_ptr,
+ offsetof(spinlock_t, lock.wait_lock.magic),
+ SPINLOCK_MAGIC) ||
+ test_magic(lock_rwlock_ptr,
+ offsetof(rwlock_t, rtmutex.wait_lock.magic),
+ SPINLOCK_MAGIC) ||
+ test_magic(lock_mutex_ptr,
+ offsetof(struct mutex, lock.wait_lock.magic),
+ SPINLOCK_MAGIC) ||
+ test_magic(lock_rwsem_ptr,
+ offsetof(struct rw_semaphore, rtmutex.wait_lock.magic),
+ SPINLOCK_MAGIC))
+ return -EINVAL;
+#else
if (test_magic(lock_spinlock_ptr,
offsetof(spinlock_t, rlock.magic),
SPINLOCK_MAGIC) ||
@@ -498,6 +513,7 @@ static int __init test_lockup_init(void)
offsetof(struct rw_semaphore, wait_lock.magic),
SPINLOCK_MAGIC))
return -EINVAL;
+#endif
#endif
if ((wait_state != TASK_RUNNING ||
diff --git a/mm/Kconfig b/mm/Kconfig
index cc43f5124..8510a7395 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -404,7 +404,7 @@ config NOMMU_INITIAL_TRIM_EXCESS
config TRANSPARENT_HUGEPAGE
bool "Transparent Hugepage Support"
- depends on HAVE_ARCH_TRANSPARENT_HUGEPAGE
+ depends on HAVE_ARCH_TRANSPARENT_HUGEPAGE && !PREEMPT_RT
select COMPACTION
select XARRAY_MULTI
help
@@ -958,6 +958,9 @@ config ARCH_HAS_HUGEPD
config MAPPING_DIRTY_HELPERS
bool
+config KMAP_LOCAL
+ bool
+
config PIN_MEMORY
bool "Support for pin memory"
depends on MMU && ARM64
diff --git a/mm/highmem.c b/mm/highmem.c
index efe38ab47..ad72e587c 100644
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -31,10 +31,6 @@
#include <asm/tlbflush.h>
#include <linux/vmalloc.h>
-#if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
-DEFINE_PER_CPU(int, __kmap_atomic_idx);
-#endif
-
/*
* Virtual_count is not a pure "count".
* 0 means that it is not mapped, and has not been mapped
@@ -108,9 +104,7 @@ static inline wait_queue_head_t *get_pkmap_wait_queue_head(unsigned int color)
atomic_long_t _totalhigh_pages __read_mostly;
EXPORT_SYMBOL(_totalhigh_pages);
-EXPORT_PER_CPU_SYMBOL(__kmap_atomic_idx);
-
-unsigned int nr_free_highpages (void)
+unsigned int __nr_free_highpages (void)
{
struct zone *zone;
unsigned int pages = 0;
@@ -147,7 +141,7 @@ pte_t * pkmap_page_table;
do { spin_unlock(&kmap_lock); (void)(flags); } while (0)
#endif
-struct page *kmap_to_page(void *vaddr)
+struct page *__kmap_to_page(void *vaddr)
{
unsigned long addr = (unsigned long)vaddr;
@@ -158,7 +152,7 @@ struct page *kmap_to_page(void *vaddr)
return virt_to_page(addr);
}
-EXPORT_SYMBOL(kmap_to_page);
+EXPORT_SYMBOL(__kmap_to_page);
static void flush_all_zero_pkmaps(void)
{
@@ -200,10 +194,7 @@ static void flush_all_zero_pkmaps(void)
flush_tlb_kernel_range(PKMAP_ADDR(0), PKMAP_ADDR(LAST_PKMAP));
}
-/**
- * kmap_flush_unused - flush all unused kmap mappings in order to remove stray mappings
- */
-void kmap_flush_unused(void)
+void __kmap_flush_unused(void)
{
lock_kmap();
flush_all_zero_pkmaps();
@@ -428,7 +419,250 @@ void zero_user_segments(struct page *page, unsigned start1, unsigned end1,
}
EXPORT_SYMBOL(zero_user_segments);
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
-#endif /* CONFIG_HIGHMEM */
+#endif /* CONFIG_HIGHMEM */
+
+#ifdef CONFIG_KMAP_LOCAL
+
+#include <asm/kmap_size.h>
+
+/*
+ * With DEBUG_HIGHMEM the stack depth is doubled and every second
+ * slot is unused which acts as a guard page
+ */
+#ifdef CONFIG_DEBUG_HIGHMEM
+# define KM_INCR 2
+#else
+# define KM_INCR 1
+#endif
+
+static inline int kmap_local_idx_push(void)
+{
+ WARN_ON_ONCE(in_irq() && !irqs_disabled());
+ current->kmap_ctrl.idx += KM_INCR;
+ BUG_ON(current->kmap_ctrl.idx >= KM_MAX_IDX);
+ return current->kmap_ctrl.idx - 1;
+
+}
+
+static inline int kmap_local_idx(void)
+{
+ return current->kmap_ctrl.idx - 1;
+}
+
+static inline void kmap_local_idx_pop(void)
+{
+ current->kmap_ctrl.idx -= KM_INCR;
+ BUG_ON(current->kmap_ctrl.idx < 0);
+}
+
+#ifndef arch_kmap_local_post_map
+# define arch_kmap_local_post_map(vaddr, pteval) do { } while (0)
+#endif
+
+#ifndef arch_kmap_local_pre_unmap
+# define arch_kmap_local_pre_unmap(vaddr) do { } while (0)
+#endif
+
+#ifndef arch_kmap_local_post_unmap
+# define arch_kmap_local_post_unmap(vaddr) do { } while (0)
+#endif
+
+#ifndef arch_kmap_local_map_idx
+#define arch_kmap_local_map_idx(idx, pfn) kmap_local_calc_idx(idx)
+#endif
+
+#ifndef arch_kmap_local_unmap_idx
+#define arch_kmap_local_unmap_idx(idx, vaddr) kmap_local_calc_idx(idx)
+#endif
+
+#ifndef arch_kmap_local_high_get
+static inline void *arch_kmap_local_high_get(struct page *page)
+{
+ return NULL;
+}
+#endif
+
+/* Unmap a local mapping which was obtained by kmap_high_get() */
+static inline bool kmap_high_unmap_local(unsigned long vaddr)
+{
+#ifdef ARCH_NEEDS_KMAP_HIGH_GET
+ if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) {
+ kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)]));
+ return true;
+ }
+#endif
+ return false;
+}
+
+static inline int kmap_local_calc_idx(int idx)
+{
+ return idx + KM_MAX_IDX * smp_processor_id();
+}
+
+static pte_t *__kmap_pte;
+
+static pte_t *kmap_get_pte(void)
+{
+ if (!__kmap_pte)
+ __kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
+ return __kmap_pte;
+}
+
+void *__kmap_local_pfn_prot(unsigned long pfn, pgprot_t prot)
+{
+ pte_t pteval, *kmap_pte = kmap_get_pte();
+ unsigned long vaddr;
+ int idx;
+
+ /*
+ * Disable migration so resulting virtual address is stable
+ * accross preemption.
+ */
+ migrate_disable();
+ preempt_disable();
+ idx = arch_kmap_local_map_idx(kmap_local_idx_push(), pfn);
+ vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+ BUG_ON(!pte_none(*(kmap_pte - idx)));
+ pteval = pfn_pte(pfn, prot);
+ set_pte_at(&init_mm, vaddr, kmap_pte - idx, pteval);
+ arch_kmap_local_post_map(vaddr, pteval);
+ current->kmap_ctrl.pteval[kmap_local_idx()] = pteval;
+ preempt_enable();
+
+ return (void *)vaddr;
+}
+EXPORT_SYMBOL_GPL(__kmap_local_pfn_prot);
+
+void *__kmap_local_page_prot(struct page *page, pgprot_t prot)
+{
+ void *kmap;
+
+ if (!PageHighMem(page))
+ return page_address(page);
+
+ /* Try kmap_high_get() if architecture has it enabled */
+ kmap = arch_kmap_local_high_get(page);
+ if (kmap)
+ return kmap;
+
+ return __kmap_local_pfn_prot(page_to_pfn(page), prot);
+}
+EXPORT_SYMBOL(__kmap_local_page_prot);
+
+void kunmap_local_indexed(void *vaddr)
+{
+ unsigned long addr = (unsigned long) vaddr & PAGE_MASK;
+ pte_t *kmap_pte = kmap_get_pte();
+ int idx;
+
+ if (addr < __fix_to_virt(FIX_KMAP_END) ||
+ addr > __fix_to_virt(FIX_KMAP_BEGIN)) {
+ /*
+ * Handle mappings which were obtained by kmap_high_get()
+ * first as the virtual address of such mappings is below
+ * PAGE_OFFSET. Warn for all other addresses which are in
+ * the user space part of the virtual address space.
+ */
+ if (!kmap_high_unmap_local(addr))
+ WARN_ON_ONCE(addr < PAGE_OFFSET);
+ return;
+ }
+
+ preempt_disable();
+ idx = arch_kmap_local_unmap_idx(kmap_local_idx(), addr);
+ WARN_ON_ONCE(addr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
+
+ arch_kmap_local_pre_unmap(addr);
+ pte_clear(&init_mm, addr, kmap_pte - idx);
+ arch_kmap_local_post_unmap(addr);
+ current->kmap_ctrl.pteval[kmap_local_idx()] = __pte(0);
+ kmap_local_idx_pop();
+ preempt_enable();
+ migrate_enable();
+}
+EXPORT_SYMBOL(kunmap_local_indexed);
+
+/*
+ * Invoked before switch_to(). This is safe even when during or after
+ * clearing the maps an interrupt which needs a kmap_local happens because
+ * the task::kmap_ctrl.idx is not modified by the unmapping code so a
+ * nested kmap_local will use the next unused index and restore the index
+ * on unmap. The already cleared kmaps of the outgoing task are irrelevant
+ * because the interrupt context does not know about them. The same applies
+ * when scheduling back in for an interrupt which happens before the
+ * restore is complete.
+ */
+void __kmap_local_sched_out(void)
+{
+ struct task_struct *tsk = current;
+ pte_t *kmap_pte = kmap_get_pte();
+ int i;
+
+ /* Clear kmaps */
+ for (i = 0; i < tsk->kmap_ctrl.idx; i++) {
+ pte_t pteval = tsk->kmap_ctrl.pteval[i];
+ unsigned long addr;
+ int idx;
+
+ /* With debug all even slots are unmapped and act as guard */
+ if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !(i & 0x01)) {
+ WARN_ON_ONCE(!pte_none(pteval));
+ continue;
+ }
+ if (WARN_ON_ONCE(pte_none(pteval)))
+ continue;
+
+ /*
+ * This is a horrible hack for XTENSA to calculate the
+ * coloured PTE index. Uses the PFN encoded into the pteval
+ * and the map index calculation because the actual mapped
+ * virtual address is not stored in task::kmap_ctrl.
+ * For any sane architecture this is optimized out.
+ */
+ idx = arch_kmap_local_map_idx(i, pte_pfn(pteval));
+
+ addr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+ arch_kmap_local_pre_unmap(addr);
+ pte_clear(&init_mm, addr, kmap_pte - idx);
+ arch_kmap_local_post_unmap(addr);
+ }
+}
+
+void __kmap_local_sched_in(void)
+{
+ struct task_struct *tsk = current;
+ pte_t *kmap_pte = kmap_get_pte();
+ int i;
+
+ /* Restore kmaps */
+ for (i = 0; i < tsk->kmap_ctrl.idx; i++) {
+ pte_t pteval = tsk->kmap_ctrl.pteval[i];
+ unsigned long addr;
+ int idx;
+
+ /* With debug all even slots are unmapped and act as guard */
+ if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !(i & 0x01)) {
+ WARN_ON_ONCE(!pte_none(pteval));
+ continue;
+ }
+ if (WARN_ON_ONCE(pte_none(pteval)))
+ continue;
+
+ /* See comment in __kmap_local_sched_out() */
+ idx = arch_kmap_local_map_idx(i, pte_pfn(pteval));
+ addr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+ set_pte_at(&init_mm, addr, kmap_pte - idx, pteval);
+ arch_kmap_local_post_map(addr, pteval);
+ }
+}
+
+void kmap_local_fork(struct task_struct *tsk)
+{
+ if (WARN_ON_ONCE(tsk->kmap_ctrl.idx))
+ memset(&tsk->kmap_ctrl, 0, sizeof(tsk->kmap_ctrl));
+}
+
+#endif
#if defined(HASHED_PAGE_VIRTUAL)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index daa104384..4e6661d0f 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -67,6 +67,7 @@
#include <net/sock.h>
#include <net/ip.h>
#include "slab.h"
+#include <linux/local_lock.h>
#include <linux/uaccess.h>
@@ -100,6 +101,14 @@ bool cgroup_memory_noswap __read_mostly;
static DECLARE_WAIT_QUEUE_HEAD(memcg_cgwb_frn_waitq);
#endif
+
+struct event_lock {
+ local_lock_t l;
+};
+static DEFINE_PER_CPU(struct event_lock, event_lock) = {
+ .l = INIT_LOCAL_LOCK(l),
+};
+
/* Whether legacy memory+swap accounting is active */
static bool do_memsw_account(void)
{
@@ -760,6 +769,7 @@ void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
memcg = pn->memcg;
+ preempt_disable_rt();
/* Update memcg */
__this_cpu_add(memcg->vmstats_percpu->state[idx], val);
@@ -767,6 +777,7 @@ void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
__this_cpu_add(pn->lruvec_stats_percpu->state[idx], val);
memcg_rstat_updated(memcg);
+ preempt_enable_rt();
}
/**
@@ -2180,6 +2191,7 @@ void unlock_page_memcg(struct page *page)
EXPORT_SYMBOL(unlock_page_memcg);
struct memcg_stock_pcp {
+ local_lock_t lock;
struct mem_cgroup *cached; /* this never be root cgroup */
unsigned int nr_pages;
@@ -2231,7 +2243,7 @@ static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
if (nr_pages > MEMCG_CHARGE_BATCH)
return ret;
- local_irq_save(flags);
+ local_lock_irqsave(&memcg_stock.lock, flags);
stock = this_cpu_ptr(&memcg_stock);
if (memcg == stock->cached && stock->nr_pages >= nr_pages) {
@@ -2239,7 +2251,7 @@ static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
ret = true;
}
- local_irq_restore(flags);
+ local_unlock_irqrestore(&memcg_stock.lock, flags);
return ret;
}
@@ -2274,14 +2286,14 @@ static void drain_local_stock(struct work_struct *dummy)
* The only protection from memory hotplug vs. drain_stock races is
* that we always operate on local CPU stock here with IRQ disabled
*/
- local_irq_save(flags);
+ local_lock_irqsave(&memcg_stock.lock, flags);
stock = this_cpu_ptr(&memcg_stock);
drain_obj_stock(stock);
drain_stock(stock);
clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags);
- local_irq_restore(flags);
+ local_unlock_irqrestore(&memcg_stock.lock, flags);
}
/*
@@ -2293,7 +2305,7 @@ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
struct memcg_stock_pcp *stock;
unsigned long flags;
- local_irq_save(flags);
+ local_lock_irqsave(&memcg_stock.lock, flags);
stock = this_cpu_ptr(&memcg_stock);
if (stock->cached != memcg) { /* reset if necessary */
@@ -2306,7 +2318,7 @@ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
if (stock->nr_pages > MEMCG_CHARGE_BATCH)
drain_stock(stock);
- local_irq_restore(flags);
+ local_unlock_irqrestore(&memcg_stock.lock, flags);
}
/*
@@ -2326,7 +2338,7 @@ static void drain_all_stock(struct mem_cgroup *root_memcg)
* as well as workers from this path always operate on the local
* per-cpu data. CPU up doesn't touch memcg_stock at all.
*/
- curcpu = get_cpu();
+ curcpu = get_cpu_light();
for_each_online_cpu(cpu) {
struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu);
struct mem_cgroup *memcg;
@@ -2349,7 +2361,7 @@ static void drain_all_stock(struct mem_cgroup *root_memcg)
schedule_work_on(cpu, &stock->work);
}
}
- put_cpu();
+ put_cpu_light();
mutex_unlock(&percpu_charge_mutex);
}
@@ -3182,7 +3194,7 @@ static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
unsigned long flags;
bool ret = false;
- local_irq_save(flags);
+ local_lock_irqsave(&memcg_stock.lock, flags);
stock = this_cpu_ptr(&memcg_stock);
if (objcg == stock->cached_objcg && stock->nr_bytes >= nr_bytes) {
@@ -3190,7 +3202,7 @@ static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
ret = true;
}
- local_irq_restore(flags);
+ local_unlock_irqrestore(&memcg_stock.lock, flags);
return ret;
}
@@ -3246,7 +3258,7 @@ static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
struct memcg_stock_pcp *stock;
unsigned long flags;
- local_irq_save(flags);
+ local_lock_irqsave(&memcg_stock.lock, flags);
stock = this_cpu_ptr(&memcg_stock);
if (stock->cached_objcg != objcg) { /* reset if necessary */
@@ -3260,7 +3272,7 @@ static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
if (stock->nr_bytes > PAGE_SIZE)
drain_obj_stock(stock);
- local_irq_restore(flags);
+ local_unlock_irqrestore(&memcg_stock.lock, flags);
}
int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size)
@@ -6989,12 +7001,12 @@ static int mem_cgroup_move_account(struct page *page,
ret = 0;
- local_irq_disable();
+ local_lock_irq(&event_lock.l);
mem_cgroup_charge_statistics(to, page, nr_pages);
memcg_check_events(to, page);
mem_cgroup_charge_statistics(from, page, -nr_pages);
memcg_check_events(from, page);
- local_irq_enable();
+ local_unlock_irq(&event_lock.l);
out_unlock:
unlock_page(page);
out:
@@ -7983,10 +7995,10 @@ int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask)
css_get(&memcg->css);
commit_charge(page, memcg);
- local_irq_disable();
+ local_lock_irq(&event_lock.l);
mem_cgroup_charge_statistics(memcg, page, nr_pages);
memcg_check_events(memcg, page);
- local_irq_enable();
+ local_unlock_irq(&event_lock.l);
/*
* Cgroup1's unified memory+swap counter has been charged with the
@@ -8042,11 +8054,11 @@ static void uncharge_batch(const struct uncharge_gather *ug)
memcg_oom_recover(ug->memcg);
}
- local_irq_save(flags);
+ local_lock_irqsave(&event_lock.l, flags);
__count_memcg_events(ug->memcg, PGPGOUT, ug->pgpgout);
__this_cpu_add(ug->memcg->vmstats_percpu->nr_page_events, ug->nr_memory);
memcg_check_events(ug->memcg, ug->dummy_page);
- local_irq_restore(flags);
+ local_unlock_irqrestore(&event_lock.l, flags);
/* drop reference from uncharge_page */
css_put(&ug->memcg->css);
@@ -8218,10 +8230,10 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage)
css_get(&memcg->css);
commit_charge(newpage, memcg);
- local_irq_save(flags);
+ local_lock_irqsave(&event_lock.l, flags);
mem_cgroup_charge_statistics(memcg, newpage, nr_pages);
memcg_check_events(memcg, newpage);
- local_irq_restore(flags);
+ local_unlock_irqrestore(&event_lock.l, flags);
}
DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key);
@@ -8351,9 +8363,13 @@ static int __init mem_cgroup_init(void)
cpuhp_setup_state_nocalls(CPUHP_MM_MEMCQ_DEAD, "mm/memctrl:dead", NULL,
memcg_hotplug_cpu_dead);
- for_each_possible_cpu(cpu)
- INIT_WORK(&per_cpu_ptr(&memcg_stock, cpu)->work,
- drain_local_stock);
+ for_each_possible_cpu(cpu) {
+ struct memcg_stock_pcp *stock;
+
+ stock = per_cpu_ptr(&memcg_stock, cpu);
+ INIT_WORK(&stock->work, drain_local_stock);
+ local_lock_init(&stock->lock);
+ }
for_each_node(node) {
struct mem_cgroup_tree_per_node *rtpn;
@@ -8403,6 +8419,7 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
struct mem_cgroup *memcg, *swap_memcg;
unsigned int nr_entries;
unsigned short oldid;
+ unsigned long flags;
VM_BUG_ON_PAGE(PageLRU(page), page);
VM_BUG_ON_PAGE(page_count(page), page);
@@ -8448,9 +8465,13 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
* important here to have the interrupts disabled because it is the
* only synchronisation we have for updating the per-CPU variables.
*/
+ local_lock_irqsave(&event_lock.l, flags);
+#ifndef CONFIG_PREEMPT_RT
VM_BUG_ON(!irqs_disabled());
+#endif
mem_cgroup_charge_statistics(memcg, page, -nr_entries);
memcg_check_events(memcg, page);
+ local_unlock_irqrestore(&event_lock.l, flags);
css_put(&memcg->css);
}
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 7cf3cd1d0..024baa31c 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -61,6 +61,7 @@
#include <linux/hugetlb.h>
#include <linux/sched/rt.h>
#include <linux/sched/mm.h>
+#include <linux/local_lock.h>
#include <linux/page_owner.h>
#include <linux/kthread.h>
#include <linux/memcontrol.h>
@@ -393,6 +394,13 @@ EXPORT_SYMBOL(nr_node_ids);
EXPORT_SYMBOL(nr_online_nodes);
#endif
+struct pa_lock {
+ local_lock_t l;
+};
+static DEFINE_PER_CPU(struct pa_lock, pa_lock) = {
+ .l = INIT_LOCAL_LOCK(l),
+};
+
int page_group_by_mobility_disabled __read_mostly;
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
@@ -1337,7 +1345,7 @@ static inline void prefetch_buddy(struct page *page)
}
/*
- * Frees a number of pages from the PCP lists
+ * Frees a number of pages which have been collected from the pcp lists.
* Assumes all pages on list are in same zone, and of same order.
* count is the number of pages to free.
*
@@ -1347,15 +1355,56 @@ static inline void prefetch_buddy(struct page *page)
* And clear the zone's pages_scanned counter, to hold off the "all pages are
* pinned" detection logic.
*/
-static void free_pcppages_bulk(struct zone *zone, int count,
- struct per_cpu_pages *pcp)
+static void free_pcppages_bulk(struct zone *zone, struct list_head *head,
+ bool zone_retry)
+{
+ bool isolated_pageblocks;
+ struct page *page, *tmp;
+ unsigned long flags;
+
+ spin_lock_irqsave(&zone->lock, flags);
+ isolated_pageblocks = has_isolate_pageblock(zone);
+
+ /*
+ * Use safe version since after __free_one_page(),
+ * page->lru.next will not point to original list.
+ */
+ list_for_each_entry_safe(page, tmp, head, lru) {
+ int mt = get_pcppage_migratetype(page);
+
+ if (page_zone(page) != zone) {
+ /*
+ * free_unref_page_list() sorts pages by zone. If we end
+ * up with pages from a different NUMA nodes belonging
+ * to the same ZONE index then we need to redo with the
+ * correct ZONE pointer. Skip the page for now, redo it
+ * on the next iteration.
+ */
+ WARN_ON_ONCE(zone_retry == false);
+ if (zone_retry)
+ continue;
+ }
+
+ /* MIGRATE_ISOLATE page should not go to pcplists */
+ VM_BUG_ON_PAGE(is_migrate_isolate(mt), page);
+ /* Pageblock could have been isolated meanwhile */
+ if (unlikely(isolated_pageblocks))
+ mt = get_pageblock_migratetype(page);
+
+ list_del(&page->lru);
+ __free_one_page(page, page_to_pfn(page), zone, 0, mt, FPI_NONE);
+ trace_mm_page_pcpu_drain(page, 0, mt);
+ }
+ spin_unlock_irqrestore(&zone->lock, flags);
+}
+
+static void isolate_pcp_pages(int count, struct per_cpu_pages *pcp,
+ struct list_head *dst)
{
int migratetype = 0;
int batch_free = 0;
int prefetch_nr = READ_ONCE(pcp->batch);
- bool isolated_pageblocks;
- struct page *page, *tmp;
- LIST_HEAD(head);
+ struct page *page;
/*
* Ensure proper count is passed which otherwise would stuck in the
@@ -1392,7 +1441,7 @@ static void free_pcppages_bulk(struct zone *zone, int count,
if (bulkfree_pcp_prepare(page))
continue;
- list_add_tail(&page->lru, &head);
+ list_add_tail(&page->lru, dst);
/*
* We are going to put the page back to the global
@@ -1409,26 +1458,6 @@ static void free_pcppages_bulk(struct zone *zone, int count,
}
} while (--count && --batch_free && !list_empty(list));
}
-
- spin_lock(&zone->lock);
- isolated_pageblocks = has_isolate_pageblock(zone);
-
- /*
- * Use safe version since after __free_one_page(),
- * page->lru.next will not point to original list.
- */
- list_for_each_entry_safe(page, tmp, &head, lru) {
- int mt = get_pcppage_migratetype(page);
- /* MIGRATE_ISOLATE page should not go to pcplists */
- VM_BUG_ON_PAGE(is_migrate_isolate(mt), page);
- /* Pageblock could have been isolated meanwhile */
- if (unlikely(isolated_pageblocks))
- mt = get_pageblock_migratetype(page);
-
- __free_one_page(page, page_to_pfn(page), zone, 0, mt, FPI_NONE);
- trace_mm_page_pcpu_drain(page, 0, mt);
- }
- spin_unlock(&zone->lock);
}
static void free_one_page(struct zone *zone,
@@ -1530,11 +1559,11 @@ static void __free_pages_ok(struct page *page, unsigned int order,
return;
migratetype = get_pfnblock_migratetype(page, pfn);
- local_irq_save(flags);
+ local_lock_irqsave(&pa_lock.l, flags);
__count_vm_events(PGFREE, 1 << order);
free_one_page(page_zone(page), page, pfn, order, migratetype,
fpi_flags);
- local_irq_restore(flags);
+ local_unlock_irqrestore(&pa_lock.l, flags);
}
void __free_pages_core(struct page *page, unsigned int order)
@@ -2945,13 +2974,18 @@ void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
{
unsigned long flags;
int to_drain, batch;
+ LIST_HEAD(dst);
- local_irq_save(flags);
+ local_lock_irqsave(&pa_lock.l, flags);
batch = READ_ONCE(pcp->batch);
to_drain = min(pcp->count, batch);
if (to_drain > 0)
- free_pcppages_bulk(zone, to_drain, pcp);
- local_irq_restore(flags);
+ isolate_pcp_pages(to_drain, pcp, &dst);
+
+ local_unlock_irqrestore(&pa_lock.l, flags);
+
+ if (to_drain > 0)
+ free_pcppages_bulk(zone, &dst, false);
}
#endif
@@ -2967,14 +3001,21 @@ static void drain_pages_zone(unsigned int cpu, struct zone *zone)
unsigned long flags;
struct per_cpu_pageset *pset;
struct per_cpu_pages *pcp;
+ LIST_HEAD(dst);
+ int count;
- local_irq_save(flags);
+ local_lock_irqsave(&pa_lock.l, flags);
pset = per_cpu_ptr(zone->pageset, cpu);
pcp = &pset->pcp;
- if (pcp->count)
- free_pcppages_bulk(zone, pcp->count, pcp);
- local_irq_restore(flags);
+ count = pcp->count;
+ if (count)
+ isolate_pcp_pages(count, pcp, &dst);
+
+ local_unlock_irqrestore(&pa_lock.l, flags);
+
+ if (count)
+ free_pcppages_bulk(zone, &dst, false);
}
/*
@@ -3022,9 +3063,9 @@ static void drain_local_pages_wq(struct work_struct *work)
* cpu which is allright but we also have to make sure to not move to
* a different one.
*/
- preempt_disable();
+ migrate_disable();
drain_local_pages(drain->zone);
- preempt_enable();
+ migrate_enable();
}
/*
@@ -3194,7 +3235,8 @@ static bool free_unref_page_prepare(struct page *page, unsigned long pfn)
return true;
}
-static void free_unref_page_commit(struct page *page, unsigned long pfn)
+static void free_unref_page_commit(struct page *page, unsigned long pfn,
+ struct list_head *dst)
{
struct zone *zone = page_zone(page);
struct per_cpu_pages *pcp;
@@ -3223,7 +3265,8 @@ static void free_unref_page_commit(struct page *page, unsigned long pfn)
list_add(&page->lru, &pcp->lists[migratetype]);
pcp->count++;
if (pcp->count >= READ_ONCE(pcp->high))
- free_pcppages_bulk(zone, READ_ONCE(pcp->batch), pcp);
+
+ isolate_pcp_pages(READ_ONCE(pcp->batch), pcp, dst);
}
/*
@@ -3233,6 +3276,8 @@ void free_unref_page(struct page *page)
{
unsigned long flags;
unsigned long pfn = page_to_pfn(page);
+ struct zone *zone = page_zone(page);
+ LIST_HEAD(dst);
/* Free dynamic hugetlb page */
if (free_page_to_dhugetlb_pool(page))
@@ -3241,9 +3286,11 @@ void free_unref_page(struct page *page)
if (!free_unref_page_prepare(page, pfn))
return;
- local_irq_save(flags);
- free_unref_page_commit(page, pfn);
- local_irq_restore(flags);
+ local_lock_irqsave(&pa_lock.l, flags);
+ free_unref_page_commit(page, pfn, &dst);
+ local_unlock_irqrestore(&pa_lock.l, flags);
+ if (!list_empty(&dst))
+ free_pcppages_bulk(zone, &dst, false);
}
/*
@@ -3254,6 +3301,11 @@ void free_unref_page_list(struct list_head *list)
struct page *page, *next;
unsigned long flags, pfn;
int batch_count = 0;
+ struct list_head dsts[__MAX_NR_ZONES];
+ int i;
+
+ for (i = 0; i < __MAX_NR_ZONES; i++)
+ INIT_LIST_HEAD(&dsts[i]);
/* Free dynamic hugetlb page list */
free_page_list_to_dhugetlb_pool(list);
@@ -3266,25 +3318,42 @@ void free_unref_page_list(struct list_head *list)
set_page_private(page, pfn);
}
- local_irq_save(flags);
+ local_lock_irqsave(&pa_lock.l, flags);
list_for_each_entry_safe(page, next, list, lru) {
unsigned long pfn = page_private(page);
+ enum zone_type type;
set_page_private(page, 0);
trace_mm_page_free_batched(page);
- free_unref_page_commit(page, pfn);
+ type = page_zonenum(page);
+ free_unref_page_commit(page, pfn, &dsts[type]);
/*
* Guard against excessive IRQ disabled times when we get
* a large list of pages to free.
*/
if (++batch_count == SWAP_CLUSTER_MAX) {
- local_irq_restore(flags);
+ local_unlock_irqrestore(&pa_lock.l, flags);
batch_count = 0;
- local_irq_save(flags);
+ local_lock_irqsave(&pa_lock.l, flags);
}
}
- local_irq_restore(flags);
+ local_unlock_irqrestore(&pa_lock.l, flags);
+
+ for (i = 0; i < __MAX_NR_ZONES; ) {
+ struct page *page;
+ struct zone *zone;
+
+ if (list_empty(&dsts[i])) {
+ i++;
+ continue;
+ }
+
+ page = list_first_entry(&dsts[i], struct page, lru);
+ zone = page_zone(page);
+
+ free_pcppages_bulk(zone, &dsts[i], true);
+ }
}
/*
@@ -3441,7 +3510,7 @@ static struct page *rmqueue_pcplist(struct zone *preferred_zone,
struct page *page;
unsigned long flags;
- local_irq_save(flags);
+ local_lock_irqsave(&pa_lock.l, flags);
pcp = &this_cpu_ptr(zone->pageset)->pcp;
list = &pcp->lists[migratetype];
page = __rmqueue_pcplist(zone, migratetype, alloc_flags, pcp, list);
@@ -3449,7 +3518,7 @@ static struct page *rmqueue_pcplist(struct zone *preferred_zone,
__count_zid_vm_events(PGALLOC, page_zonenum(page), 1);
zone_statistics(preferred_zone, zone);
}
- local_irq_restore(flags);
+ local_unlock_irqrestore(&pa_lock.l, flags);
return page;
}
@@ -3483,7 +3552,8 @@ struct page *rmqueue(struct zone *preferred_zone,
* allocate greater than order-1 page units with __GFP_NOFAIL.
*/
WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1));
- spin_lock_irqsave(&zone->lock, flags);
+ local_lock_irqsave(&pa_lock.l, flags);
+ spin_lock(&zone->lock);
do {
page = NULL;
@@ -3509,7 +3579,7 @@ struct page *rmqueue(struct zone *preferred_zone,
__count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order);
zone_statistics(preferred_zone, zone);
- local_irq_restore(flags);
+ local_unlock_irqrestore(&pa_lock.l, flags);
out:
/* Separate test+clear to avoid unnecessary atomics */
@@ -3522,7 +3592,7 @@ out:
return page;
failed:
- local_irq_restore(flags);
+ local_unlock_irqrestore(&pa_lock.l, flags);
return NULL;
}
@@ -9414,7 +9484,7 @@ void zone_pcp_reset(struct zone *zone)
struct per_cpu_pageset *pset;
/* avoid races with drain_pages() */
- local_irq_save(flags);
+ local_lock_irqsave(&pa_lock.l, flags);
if (zone->pageset != &boot_pageset) {
for_each_online_cpu(cpu) {
pset = per_cpu_ptr(zone->pageset, cpu);
@@ -9423,7 +9493,7 @@ void zone_pcp_reset(struct zone *zone)
free_percpu(zone->pageset);
zone->pageset = &boot_pageset;
}
- local_irq_restore(flags);
+ local_unlock_irqrestore(&pa_lock.l, flags);
}
#ifdef CONFIG_MEMORY_HOTREMOVE
diff --git a/mm/shmem.c b/mm/shmem.c
index 9cb612d11..22abbff47 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -307,10 +307,10 @@ static int shmem_reserve_inode(struct super_block *sb, ino_t *inop)
ino_t ino;
if (!(sb->s_flags & SB_KERNMOUNT)) {
- spin_lock(&sbinfo->stat_lock);
+ raw_spin_lock(&sbinfo->stat_lock);
if (sbinfo->max_inodes) {
if (!sbinfo->free_inodes) {
- spin_unlock(&sbinfo->stat_lock);
+ raw_spin_unlock(&sbinfo->stat_lock);
return -ENOSPC;
}
sbinfo->free_inodes--;
@@ -333,7 +333,7 @@ static int shmem_reserve_inode(struct super_block *sb, ino_t *inop)
}
*inop = ino;
}
- spin_unlock(&sbinfo->stat_lock);
+ raw_spin_unlock(&sbinfo->stat_lock);
} else if (inop) {
/*
* __shmem_file_setup, one of our callers, is lock-free: it
@@ -348,13 +348,14 @@ static int shmem_reserve_inode(struct super_block *sb, ino_t *inop)
* to worry about things like glibc compatibility.
*/
ino_t *next_ino;
+
next_ino = per_cpu_ptr(sbinfo->ino_batch, get_cpu());
ino = *next_ino;
if (unlikely(ino % SHMEM_INO_BATCH == 0)) {
- spin_lock(&sbinfo->stat_lock);
+ raw_spin_lock(&sbinfo->stat_lock);
ino = sbinfo->next_ino;
sbinfo->next_ino += SHMEM_INO_BATCH;
- spin_unlock(&sbinfo->stat_lock);
+ raw_spin_unlock(&sbinfo->stat_lock);
if (unlikely(is_zero_ino(ino)))
ino++;
}
@@ -370,9 +371,9 @@ static void shmem_free_inode(struct super_block *sb)
{
struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
if (sbinfo->max_inodes) {
- spin_lock(&sbinfo->stat_lock);
+ raw_spin_lock(&sbinfo->stat_lock);
sbinfo->free_inodes++;
- spin_unlock(&sbinfo->stat_lock);
+ raw_spin_unlock(&sbinfo->stat_lock);
}
}
@@ -1471,10 +1472,10 @@ static struct mempolicy *shmem_get_sbmpol(struct shmem_sb_info *sbinfo)
{
struct mempolicy *mpol = NULL;
if (sbinfo->mpol) {
- spin_lock(&sbinfo->stat_lock); /* prevent replace/use races */
+ raw_spin_lock(&sbinfo->stat_lock); /* prevent replace/use races */
mpol = sbinfo->mpol;
mpol_get(mpol);
- spin_unlock(&sbinfo->stat_lock);
+ raw_spin_unlock(&sbinfo->stat_lock);
}
return mpol;
}
@@ -3595,9 +3596,10 @@ static int shmem_reconfigure(struct fs_context *fc)
struct shmem_options *ctx = fc->fs_private;
struct shmem_sb_info *sbinfo = SHMEM_SB(fc->root->d_sb);
unsigned long inodes;
+ struct mempolicy *mpol = NULL;
const char *err;
- spin_lock(&sbinfo->stat_lock);
+ raw_spin_lock(&sbinfo->stat_lock);
inodes = sbinfo->max_inodes - sbinfo->free_inodes;
if ((ctx->seen & SHMEM_SEEN_BLOCKS) && ctx->blocks) {
@@ -3643,14 +3645,15 @@ static int shmem_reconfigure(struct fs_context *fc)
* Preserve previous mempolicy unless mpol remount option was specified.
*/
if (ctx->mpol) {
- mpol_put(sbinfo->mpol);
+ mpol = sbinfo->mpol;
sbinfo->mpol = ctx->mpol; /* transfers initial ref */
ctx->mpol = NULL;
}
- spin_unlock(&sbinfo->stat_lock);
+ raw_spin_unlock(&sbinfo->stat_lock);
+ mpol_put(mpol);
return 0;
out:
- spin_unlock(&sbinfo->stat_lock);
+ raw_spin_unlock(&sbinfo->stat_lock);
return invalfc(fc, "%s", err);
}
@@ -3767,7 +3770,7 @@ static int shmem_fill_super(struct super_block *sb, struct fs_context *fc)
sbinfo->mpol = ctx->mpol;
ctx->mpol = NULL;
- spin_lock_init(&sbinfo->stat_lock);
+ raw_spin_lock_init(&sbinfo->stat_lock);
if (percpu_counter_init(&sbinfo->used_blocks, 0, GFP_KERNEL))
goto failed;
spin_lock_init(&sbinfo->shrinklist_lock);
diff --git a/mm/slab.c b/mm/slab.c
index ca71d3f3e..c2653a84b 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -234,7 +234,7 @@ static void kmem_cache_node_init(struct kmem_cache_node *parent)
parent->shared = NULL;
parent->alien = NULL;
parent->colour_next = 0;
- spin_lock_init(&parent->list_lock);
+ raw_spin_lock_init(&parent->list_lock);
parent->free_objects = 0;
parent->free_touched = 0;
}
@@ -559,9 +559,9 @@ static noinline void cache_free_pfmemalloc(struct kmem_cache *cachep,
page_node = page_to_nid(page);
n = get_node(cachep, page_node);
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
free_block(cachep, &objp, 1, page_node, &list);
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
slabs_destroy(cachep, &list);
}
@@ -699,7 +699,7 @@ static void __drain_alien_cache(struct kmem_cache *cachep,
struct kmem_cache_node *n = get_node(cachep, node);
if (ac->avail) {
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
/*
* Stuff objects into the remote nodes shared array first.
* That way we could avoid the overhead of putting the objects
@@ -710,7 +710,7 @@ static void __drain_alien_cache(struct kmem_cache *cachep,
free_block(cachep, ac->entry, ac->avail, node, list);
ac->avail = 0;
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
}
}
@@ -783,9 +783,9 @@ static int __cache_free_alien(struct kmem_cache *cachep, void *objp,
slabs_destroy(cachep, &list);
} else {
n = get_node(cachep, page_node);
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
free_block(cachep, &objp, 1, page_node, &list);
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
slabs_destroy(cachep, &list);
}
return 1;
@@ -826,10 +826,10 @@ static int init_cache_node(struct kmem_cache *cachep, int node, gfp_t gfp)
*/
n = get_node(cachep, node);
if (n) {
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
n->free_limit = (1 + nr_cpus_node(node)) * cachep->batchcount +
cachep->num;
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
return 0;
}
@@ -908,7 +908,7 @@ static int setup_kmem_cache_node(struct kmem_cache *cachep,
goto fail;
n = get_node(cachep, node);
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
if (n->shared && force_change) {
free_block(cachep, n->shared->entry,
n->shared->avail, node, &list);
@@ -926,7 +926,7 @@ static int setup_kmem_cache_node(struct kmem_cache *cachep,
new_alien = NULL;
}
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
slabs_destroy(cachep, &list);
/*
@@ -965,7 +965,7 @@ static void cpuup_canceled(long cpu)
if (!n)
continue;
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
/* Free limit for this kmem_cache_node */
n->free_limit -= cachep->batchcount;
@@ -976,7 +976,7 @@ static void cpuup_canceled(long cpu)
nc->avail = 0;
if (!cpumask_empty(mask)) {
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
goto free_slab;
}
@@ -990,7 +990,7 @@ static void cpuup_canceled(long cpu)
alien = n->alien;
n->alien = NULL;
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
kfree(shared);
if (alien) {
@@ -1174,7 +1174,7 @@ static void __init init_list(struct kmem_cache *cachep, struct kmem_cache_node *
/*
* Do not assume that spinlocks can be initialized via memcpy:
*/
- spin_lock_init(&ptr->list_lock);
+ raw_spin_lock_init(&ptr->list_lock);
MAKE_ALL_LISTS(cachep, ptr, nodeid);
cachep->node[nodeid] = ptr;
@@ -1345,11 +1345,11 @@ slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid)
for_each_kmem_cache_node(cachep, node, n) {
unsigned long total_slabs, free_slabs, free_objs;
- spin_lock_irqsave(&n->list_lock, flags);
+ raw_spin_lock_irqsave(&n->list_lock, flags);
total_slabs = n->total_slabs;
free_slabs = n->free_slabs;
free_objs = n->free_objects;
- spin_unlock_irqrestore(&n->list_lock, flags);
+ raw_spin_unlock_irqrestore(&n->list_lock, flags);
pr_warn(" node %d: slabs: %ld/%ld, objs: %ld/%ld\n",
node, total_slabs - free_slabs, total_slabs,
@@ -2106,7 +2106,7 @@ static void check_spinlock_acquired(struct kmem_cache *cachep)
{
#ifdef CONFIG_SMP
check_irq_off();
- assert_spin_locked(&get_node(cachep, numa_mem_id())->list_lock);
+ assert_raw_spin_locked(&get_node(cachep, numa_mem_id())->list_lock);
#endif
}
@@ -2114,7 +2114,7 @@ static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node)
{
#ifdef CONFIG_SMP
check_irq_off();
- assert_spin_locked(&get_node(cachep, node)->list_lock);
+ assert_raw_spin_locked(&get_node(cachep, node)->list_lock);
#endif
}
@@ -2154,9 +2154,9 @@ static void do_drain(void *arg)
check_irq_off();
ac = cpu_cache_get(cachep);
n = get_node(cachep, node);
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
free_block(cachep, ac->entry, ac->avail, node, &list);
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
ac->avail = 0;
slabs_destroy(cachep, &list);
}
@@ -2174,9 +2174,9 @@ static void drain_cpu_caches(struct kmem_cache *cachep)
drain_alien_cache(cachep, n->alien);
for_each_kmem_cache_node(cachep, node, n) {
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
drain_array_locked(cachep, n->shared, node, true, &list);
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
slabs_destroy(cachep, &list);
}
@@ -2198,10 +2198,10 @@ static int drain_freelist(struct kmem_cache *cache,
nr_freed = 0;
while (nr_freed < tofree && !list_empty(&n->slabs_free)) {
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
p = n->slabs_free.prev;
if (p == &n->slabs_free) {
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
goto out;
}
@@ -2214,7 +2214,7 @@ static int drain_freelist(struct kmem_cache *cache,
* to the cache.
*/
n->free_objects -= cache->num;
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
slab_destroy(cache, page);
nr_freed++;
}
@@ -2650,7 +2650,7 @@ static void cache_grow_end(struct kmem_cache *cachep, struct page *page)
INIT_LIST_HEAD(&page->slab_list);
n = get_node(cachep, page_to_nid(page));
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
n->total_slabs++;
if (!page->active) {
list_add_tail(&page->slab_list, &n->slabs_free);
@@ -2660,7 +2660,7 @@ static void cache_grow_end(struct kmem_cache *cachep, struct page *page)
STATS_INC_GROWN(cachep);
n->free_objects += cachep->num - page->active;
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
fixup_objfreelist_debug(cachep, &list);
}
@@ -2826,7 +2826,7 @@ static struct page *get_first_slab(struct kmem_cache_node *n, bool pfmemalloc)
{
struct page *page;
- assert_spin_locked(&n->list_lock);
+ assert_raw_spin_locked(&n->list_lock);
page = list_first_entry_or_null(&n->slabs_partial, struct page,
slab_list);
if (!page) {
@@ -2853,10 +2853,10 @@ static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep,
if (!gfp_pfmemalloc_allowed(flags))
return NULL;
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
page = get_first_slab(n, true);
if (!page) {
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
return NULL;
}
@@ -2865,7 +2865,7 @@ static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep,
fixup_slab_list(cachep, n, page, &list);
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
fixup_objfreelist_debug(cachep, &list);
return obj;
@@ -2924,7 +2924,7 @@ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags)
if (!n->free_objects && (!shared || !shared->avail))
goto direct_grow;
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
shared = READ_ONCE(n->shared);
/* See if we can refill from the shared array */
@@ -2948,7 +2948,7 @@ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags)
must_grow:
n->free_objects -= ac->avail;
alloc_done:
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
fixup_objfreelist_debug(cachep, &list);
direct_grow:
@@ -3173,7 +3173,7 @@ static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags,
BUG_ON(!n);
check_irq_off();
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
page = get_first_slab(n, false);
if (!page)
goto must_grow;
@@ -3191,12 +3191,12 @@ static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags,
fixup_slab_list(cachep, n, page, &list);
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
fixup_objfreelist_debug(cachep, &list);
return obj;
must_grow:
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
page = cache_grow_begin(cachep, gfp_exact_node(flags), nodeid);
if (page) {
/* This slab isn't counted yet so don't update free_objects */
@@ -3384,7 +3384,7 @@ static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac)
check_irq_off();
n = get_node(cachep, node);
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
if (n->shared) {
struct array_cache *shared_array = n->shared;
int max = shared_array->limit - shared_array->avail;
@@ -3413,7 +3413,7 @@ free_done:
STATS_SET_FREEABLE(cachep, i);
}
#endif
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
ac->avail -= batchcount;
memmove(ac->entry, &(ac->entry[batchcount]), sizeof(void *)*ac->avail);
slabs_destroy(cachep, &list);
@@ -3849,9 +3849,9 @@ static int do_tune_cpucache(struct kmem_cache *cachep, int limit,
node = cpu_to_mem(cpu);
n = get_node(cachep, node);
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
free_block(cachep, ac->entry, ac->avail, node, &list);
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
slabs_destroy(cachep, &list);
}
free_percpu(prev);
@@ -3946,9 +3946,9 @@ static void drain_array(struct kmem_cache *cachep, struct kmem_cache_node *n,
return;
}
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
drain_array_locked(cachep, ac, node, false, &list);
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
slabs_destroy(cachep, &list);
}
@@ -4032,7 +4032,7 @@ void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo)
for_each_kmem_cache_node(cachep, node, n) {
check_irq_on();
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
total_slabs += n->total_slabs;
free_slabs += n->free_slabs;
@@ -4041,7 +4041,7 @@ void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo)
if (n->shared)
shared_avail += n->shared->avail;
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
}
num_objs = total_slabs * cachep->num;
active_slabs = total_slabs - free_slabs;
diff --git a/mm/slab.h b/mm/slab.h
index a0e92203e..7d5d941de 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -524,7 +524,7 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s,
* The slab lists for all objects.
*/
struct kmem_cache_node {
- spinlock_t list_lock;
+ raw_spinlock_t list_lock;
#ifdef CONFIG_SLAB
struct list_head slabs_partial; /* partial list first, better asm code */
diff --git a/mm/slub.c b/mm/slub.c
index 9dd4cc478..46764081e 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -458,7 +458,7 @@ static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page,
#ifdef CONFIG_SLUB_DEBUG
static unsigned long object_map[BITS_TO_LONGS(MAX_OBJS_PER_PAGE)];
-static DEFINE_SPINLOCK(object_map_lock);
+static DEFINE_RAW_SPINLOCK(object_map_lock);
/*
* Determine a map of object in use on a page.
@@ -474,7 +474,7 @@ static unsigned long *get_map(struct kmem_cache *s, struct page *page)
VM_BUG_ON(!irqs_disabled());
- spin_lock(&object_map_lock);
+ raw_spin_lock(&object_map_lock);
bitmap_zero(object_map, page->objects);
@@ -487,7 +487,7 @@ static unsigned long *get_map(struct kmem_cache *s, struct page *page)
static void put_map(unsigned long *map) __releases(&object_map_lock)
{
VM_BUG_ON(map != object_map);
- spin_unlock(&object_map_lock);
+ raw_spin_unlock(&object_map_lock);
}
static inline unsigned int size_from_object(struct kmem_cache *s)
@@ -1238,7 +1238,7 @@ static noinline int free_debug_processing(
unsigned long flags;
int ret = 0;
- spin_lock_irqsave(&n->list_lock, flags);
+ raw_spin_lock_irqsave(&n->list_lock, flags);
slab_lock(page);
if (s->flags & SLAB_CONSISTENCY_CHECKS) {
@@ -1273,7 +1273,7 @@ out:
bulk_cnt, cnt);
slab_unlock(page);
- spin_unlock_irqrestore(&n->list_lock, flags);
+ raw_spin_unlock_irqrestore(&n->list_lock, flags);
if (!ret)
slab_fix(s, "Object at 0x%p not freed", object);
return ret;
@@ -1521,6 +1521,12 @@ static bool freelist_corrupted(struct kmem_cache *s, struct page *page,
}
#endif /* CONFIG_SLUB_DEBUG */
+struct slub_free_list {
+ raw_spinlock_t lock;
+ struct list_head list;
+};
+static DEFINE_PER_CPU(struct slub_free_list, slub_free_list);
+
/*
* Hooks for other subsystems that check memory allocations. In a typical
* production configuration these hooks all should produce no code at all.
@@ -1776,10 +1782,18 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
void *start, *p, *next;
int idx;
bool shuffle;
+ bool enableirqs = false;
flags &= gfp_allowed_mask;
if (gfpflags_allow_blocking(flags))
+ enableirqs = true;
+
+#ifdef CONFIG_PREEMPT_RT
+ if (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND)
+ enableirqs = true;
+#endif
+ if (enableirqs)
local_irq_enable();
flags |= s->allocflags;
@@ -1838,7 +1852,7 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
page->frozen = 1;
out:
- if (gfpflags_allow_blocking(flags))
+ if (enableirqs)
local_irq_disable();
if (!page)
return NULL;
@@ -1881,6 +1895,16 @@ static void __free_slab(struct kmem_cache *s, struct page *page)
__free_pages(page, order);
}
+static void free_delayed(struct list_head *h)
+{
+ while (!list_empty(h)) {
+ struct page *page = list_first_entry(h, struct page, lru);
+
+ list_del(&page->lru);
+ __free_slab(page->slab_cache, page);
+ }
+}
+
static void rcu_free_slab(struct rcu_head *h)
{
struct page *page = container_of(h, struct page, rcu_head);
@@ -1892,6 +1916,12 @@ static void free_slab(struct kmem_cache *s, struct page *page)
{
if (unlikely(s->flags & SLAB_TYPESAFE_BY_RCU)) {
call_rcu(&page->rcu_head, rcu_free_slab);
+ } else if (irqs_disabled()) {
+ struct slub_free_list *f = this_cpu_ptr(&slub_free_list);
+
+ raw_spin_lock(&f->lock);
+ list_add(&page->lru, &f->list);
+ raw_spin_unlock(&f->lock);
} else
__free_slab(s, page);
}
@@ -1999,7 +2029,7 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
if (!n || !n->nr_partial)
return NULL;
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
list_for_each_entry_safe(page, page2, &n->partial, slab_list) {
void *t;
@@ -2024,7 +2054,7 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
break;
}
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
return object;
}
@@ -2267,7 +2297,7 @@ redo:
* that acquire_slab() will see a slab page that
* is frozen
*/
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
}
} else {
m = M_FULL;
@@ -2279,7 +2309,7 @@ redo:
* slabs from diagnostic functions will not see
* any frozen slabs.
*/
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
}
#endif
}
@@ -2304,7 +2334,7 @@ redo:
goto redo;
if (lock)
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
if (m == M_PARTIAL)
stat(s, tail);
@@ -2344,10 +2374,10 @@ static void unfreeze_partials(struct kmem_cache *s,
n2 = get_node(s, page_to_nid(page));
if (n != n2) {
if (n)
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
n = n2;
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
}
do {
@@ -2376,7 +2406,7 @@ static void unfreeze_partials(struct kmem_cache *s,
}
if (n)
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
while (discard_page) {
page = discard_page;
@@ -2413,14 +2443,21 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain)
pobjects = oldpage->pobjects;
pages = oldpage->pages;
if (drain && pobjects > slub_cpu_partial(s)) {
+ struct slub_free_list *f;
unsigned long flags;
+ LIST_HEAD(tofree);
/*
* partial array is full. Move the existing
* set to the per node partial list.
*/
local_irq_save(flags);
unfreeze_partials(s, this_cpu_ptr(s->cpu_slab));
+ f = this_cpu_ptr(&slub_free_list);
+ raw_spin_lock(&f->lock);
+ list_splice_init(&f->list, &tofree);
+ raw_spin_unlock(&f->lock);
local_irq_restore(flags);
+ free_delayed(&tofree);
oldpage = NULL;
pobjects = 0;
pages = 0;
@@ -2486,7 +2523,19 @@ static bool has_cpu_slab(int cpu, void *info)
static void flush_all(struct kmem_cache *s)
{
+ LIST_HEAD(tofree);
+ int cpu;
+
on_each_cpu_cond(has_cpu_slab, flush_cpu_slab, s, 1);
+ for_each_online_cpu(cpu) {
+ struct slub_free_list *f;
+
+ f = &per_cpu(slub_free_list, cpu);
+ raw_spin_lock_irq(&f->lock);
+ list_splice_init(&f->list, &tofree);
+ raw_spin_unlock_irq(&f->lock);
+ free_delayed(&tofree);
+ }
}
/*
@@ -2541,10 +2590,10 @@ static unsigned long count_partial(struct kmem_cache_node *n,
unsigned long x = 0;
struct page *page;
- spin_lock_irqsave(&n->list_lock, flags);
+ raw_spin_lock_irqsave(&n->list_lock, flags);
list_for_each_entry(page, &n->partial, slab_list)
x += get_count(page);
- spin_unlock_irqrestore(&n->list_lock, flags);
+ raw_spin_unlock_irqrestore(&n->list_lock, flags);
return x;
}
#endif /* CONFIG_SLUB_DEBUG || CONFIG_SYSFS */
@@ -2683,8 +2732,10 @@ static inline void *get_freelist(struct kmem_cache *s, struct page *page)
* already disabled (which is the case for bulk allocation).
*/
static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
- unsigned long addr, struct kmem_cache_cpu *c)
+ unsigned long addr, struct kmem_cache_cpu *c,
+ struct list_head *to_free)
{
+ struct slub_free_list *f;
void *freelist;
struct page *page;
@@ -2753,6 +2804,13 @@ load_freelist:
VM_BUG_ON(!c->page->frozen);
c->freelist = get_freepointer(s, freelist);
c->tid = next_tid(c->tid);
+
+out:
+ f = this_cpu_ptr(&slub_free_list);
+ raw_spin_lock(&f->lock);
+ list_splice_init(&f->list, to_free);
+ raw_spin_unlock(&f->lock);
+
return freelist;
new_slab:
@@ -2768,7 +2826,7 @@ new_slab:
if (unlikely(!freelist)) {
slab_out_of_memory(s, gfpflags, node);
- return NULL;
+ goto out;
}
page = c->page;
@@ -2781,7 +2839,7 @@ new_slab:
goto new_slab; /* Slab failed checks. Next slab needed */
deactivate_slab(s, page, get_freepointer(s, freelist), c);
- return freelist;
+ goto out;
}
/*
@@ -2793,6 +2851,7 @@ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
{
void *p;
unsigned long flags;
+ LIST_HEAD(tofree);
local_irq_save(flags);
#ifdef CONFIG_PREEMPTION
@@ -2804,8 +2863,9 @@ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
c = this_cpu_ptr(s->cpu_slab);
#endif
- p = ___slab_alloc(s, gfpflags, node, addr, c);
+ p = ___slab_alloc(s, gfpflags, node, addr, c, &tofree);
local_irq_restore(flags);
+ free_delayed(&tofree);
return p;
}
@@ -2839,6 +2899,10 @@ static __always_inline void *slab_alloc_node(struct kmem_cache *s,
unsigned long tid;
struct obj_cgroup *objcg = NULL;
+ if (IS_ENABLED(CONFIG_PREEMPT_RT) && IS_ENABLED(CONFIG_DEBUG_ATOMIC_SLEEP))
+ WARN_ON_ONCE(!preemptible() &&
+ (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND));
+
s = slab_pre_alloc_hook(s, &objcg, 1, gfpflags);
if (!s)
return NULL;
@@ -3013,7 +3077,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
do {
if (unlikely(n)) {
- spin_unlock_irqrestore(&n->list_lock, flags);
+ raw_spin_unlock_irqrestore(&n->list_lock, flags);
n = NULL;
}
prior = page->freelist;
@@ -3045,7 +3109,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
* Otherwise the list_lock will synchronize with
* other processors updating the list of slabs.
*/
- spin_lock_irqsave(&n->list_lock, flags);
+ raw_spin_lock_irqsave(&n->list_lock, flags);
}
}
@@ -3087,7 +3151,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
add_partial(n, page, DEACTIVATE_TO_TAIL);
stat(s, FREE_ADD_PARTIAL);
}
- spin_unlock_irqrestore(&n->list_lock, flags);
+ raw_spin_unlock_irqrestore(&n->list_lock, flags);
return;
slab_empty:
@@ -3102,7 +3166,7 @@ slab_empty:
remove_full(s, n, page);
}
- spin_unlock_irqrestore(&n->list_lock, flags);
+ raw_spin_unlock_irqrestore(&n->list_lock, flags);
stat(s, FREE_SLAB);
discard_slab(s, page);
}
@@ -3329,9 +3393,14 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
void **p)
{
struct kmem_cache_cpu *c;
+ LIST_HEAD(to_free);
int i;
struct obj_cgroup *objcg = NULL;
+ if (IS_ENABLED(CONFIG_PREEMPT_RT) && IS_ENABLED(CONFIG_DEBUG_ATOMIC_SLEEP))
+ WARN_ON_ONCE(!preemptible() &&
+ (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND));
+
/* memcg and kmem_cache debug support */
s = slab_pre_alloc_hook(s, &objcg, size, flags);
if (unlikely(!s))
@@ -3368,7 +3437,7 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
* of re-populating per CPU c->freelist
*/
p[i] = ___slab_alloc(s, flags, NUMA_NO_NODE,
- _RET_IP_, c);
+ _RET_IP_, c, &to_free);
if (unlikely(!p[i]))
goto error;
@@ -3383,6 +3452,7 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
}
c->tid = next_tid(c->tid);
local_irq_enable();
+ free_delayed(&to_free);
/* Clear memory outside IRQ disabled fastpath loop */
if (unlikely(slab_want_init_on_alloc(flags, s))) {
@@ -3397,6 +3467,7 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
return i;
error:
local_irq_enable();
+ free_delayed(&to_free);
slab_post_alloc_hook(s, objcg, flags, i, p);
__kmem_cache_free_bulk(s, i, p);
return 0;
@@ -3532,7 +3603,7 @@ static void
init_kmem_cache_node(struct kmem_cache_node *n)
{
n->nr_partial = 0;
- spin_lock_init(&n->list_lock);
+ raw_spin_lock_init(&n->list_lock);
INIT_LIST_HEAD(&n->partial);
#ifdef CONFIG_SLUB_DEBUG
atomic_long_set(&n->nr_slabs, 0);
@@ -3927,7 +3998,7 @@ static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
struct page *page, *h;
BUG_ON(irqs_disabled());
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
list_for_each_entry_safe(page, h, &n->partial, slab_list) {
if (!page->inuse) {
remove_partial(n, page);
@@ -3937,7 +4008,7 @@ static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
"Objects remaining in %s on __kmem_cache_shutdown()");
}
}
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
list_for_each_entry_safe(page, h, &discard, slab_list)
discard_slab(s, page);
@@ -4206,7 +4277,7 @@ int __kmem_cache_shrink(struct kmem_cache *s)
for (i = 0; i < SHRINK_PROMOTE_MAX; i++)
INIT_LIST_HEAD(promote + i);
- spin_lock_irqsave(&n->list_lock, flags);
+ raw_spin_lock_irqsave(&n->list_lock, flags);
/*
* Build lists of slabs to discard or promote.
@@ -4237,7 +4308,7 @@ int __kmem_cache_shrink(struct kmem_cache *s)
for (i = SHRINK_PROMOTE_MAX - 1; i >= 0; i--)
list_splice(promote + i, &n->partial);
- spin_unlock_irqrestore(&n->list_lock, flags);
+ raw_spin_unlock_irqrestore(&n->list_lock, flags);
/* Release empty slabs */
list_for_each_entry_safe(page, t, &discard, slab_list)
@@ -4413,6 +4484,12 @@ void __init kmem_cache_init(void)
static __initdata struct kmem_cache boot_kmem_cache,
boot_kmem_cache_node;
int node;
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ raw_spin_lock_init(&per_cpu(slub_free_list, cpu).lock);
+ INIT_LIST_HEAD(&per_cpu(slub_free_list, cpu).list);
+ }
if (debug_guardpage_minorder())
slub_max_order = 0;
@@ -4611,7 +4688,7 @@ static int validate_slab_node(struct kmem_cache *s,
struct page *page;
unsigned long flags;
- spin_lock_irqsave(&n->list_lock, flags);
+ raw_spin_lock_irqsave(&n->list_lock, flags);
list_for_each_entry(page, &n->partial, slab_list) {
validate_slab(s, page);
@@ -4633,7 +4710,7 @@ static int validate_slab_node(struct kmem_cache *s,
s->name, count, atomic_long_read(&n->nr_slabs));
out:
- spin_unlock_irqrestore(&n->list_lock, flags);
+ raw_spin_unlock_irqrestore(&n->list_lock, flags);
return count;
}
@@ -4684,6 +4761,9 @@ static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags)
struct location *l;
int order;
+ if (IS_ENABLED(CONFIG_PREEMPT_RT) && flags == GFP_ATOMIC)
+ return 0;
+
order = get_order(sizeof(struct location) * max);
l = (void *)__get_free_pages(flags, order);
@@ -4812,12 +4892,12 @@ static int list_locations(struct kmem_cache *s, char *buf,
if (!atomic_long_read(&n->nr_slabs))
continue;
- spin_lock_irqsave(&n->list_lock, flags);
+ raw_spin_lock_irqsave(&n->list_lock, flags);
list_for_each_entry(page, &n->partial, slab_list)
process_slab(&t, s, page, alloc);
list_for_each_entry(page, &n->full, slab_list)
process_slab(&t, s, page, alloc);
- spin_unlock_irqrestore(&n->list_lock, flags);
+ raw_spin_unlock_irqrestore(&n->list_lock, flags);
}
for (i = 0; i < t.count; i++) {
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 6d802924d..a4ea22e5b 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1894,7 +1894,7 @@ static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
struct vmap_block *vb;
struct vmap_area *va;
unsigned long vb_idx;
- int node, err;
+ int node, err, cpu;
void *vaddr;
node = numa_node_id();
@@ -1931,11 +1931,12 @@ static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
return ERR_PTR(err);
}
- vbq = &get_cpu_var(vmap_block_queue);
+ cpu = get_cpu_light();
+ vbq = this_cpu_ptr(&vmap_block_queue);
spin_lock(&vbq->lock);
list_add_tail_rcu(&vb->free_list, &vbq->free);
spin_unlock(&vbq->lock);
- put_cpu_var(vmap_block_queue);
+ put_cpu_light();
return vaddr;
}
@@ -2000,6 +2001,7 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
struct vmap_block *vb;
void *vaddr = NULL;
unsigned int order;
+ int cpu;
BUG_ON(offset_in_page(size));
BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
@@ -2014,7 +2016,8 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
order = get_order(size);
rcu_read_lock();
- vbq = &get_cpu_var(vmap_block_queue);
+ cpu = get_cpu_light();
+ vbq = this_cpu_ptr(&vmap_block_queue);
list_for_each_entry_rcu(vb, &vbq->free, free_list) {
unsigned long pages_off;
@@ -2037,7 +2040,7 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
break;
}
- put_cpu_var(vmap_block_queue);
+ put_cpu_light();
rcu_read_unlock();
/* Allocate new block if nothing was found */
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 05433f663..afb32defb 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -321,6 +321,7 @@ void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
long x;
long t;
+ preempt_disable_rt();
x = delta + __this_cpu_read(*p);
t = __this_cpu_read(pcp->stat_threshold);
@@ -330,6 +331,7 @@ void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
x = 0;
}
__this_cpu_write(*p, x);
+ preempt_enable_rt();
}
EXPORT_SYMBOL(__mod_zone_page_state);
@@ -346,6 +348,7 @@ void __mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
delta >>= PAGE_SHIFT;
}
+ preempt_disable_rt();
x = delta + __this_cpu_read(*p);
t = __this_cpu_read(pcp->stat_threshold);
@@ -355,6 +358,7 @@ void __mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
x = 0;
}
__this_cpu_write(*p, x);
+ preempt_enable_rt();
}
EXPORT_SYMBOL(__mod_node_page_state);
@@ -387,6 +391,7 @@ void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
s8 __percpu *p = pcp->vm_stat_diff + item;
s8 v, t;
+ preempt_disable_rt();
v = __this_cpu_inc_return(*p);
t = __this_cpu_read(pcp->stat_threshold);
if (unlikely(v > t)) {
@@ -395,6 +400,7 @@ void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
zone_page_state_add(v + overstep, zone, item);
__this_cpu_write(*p, -overstep);
}
+ preempt_enable_rt();
}
void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
@@ -405,6 +411,7 @@ void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
VM_WARN_ON_ONCE(vmstat_item_in_bytes(item));
+ preempt_disable_rt();
v = __this_cpu_inc_return(*p);
t = __this_cpu_read(pcp->stat_threshold);
if (unlikely(v > t)) {
@@ -413,6 +420,7 @@ void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
node_page_state_add(v + overstep, pgdat, item);
__this_cpu_write(*p, -overstep);
}
+ preempt_enable_rt();
}
void __inc_zone_page_state(struct page *page, enum zone_stat_item item)
@@ -433,6 +441,7 @@ void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
s8 __percpu *p = pcp->vm_stat_diff + item;
s8 v, t;
+ preempt_disable_rt();
v = __this_cpu_dec_return(*p);
t = __this_cpu_read(pcp->stat_threshold);
if (unlikely(v < - t)) {
@@ -441,6 +450,7 @@ void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
zone_page_state_add(v - overstep, zone, item);
__this_cpu_write(*p, overstep);
}
+ preempt_enable_rt();
}
void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
@@ -451,6 +461,7 @@ void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
VM_WARN_ON_ONCE(vmstat_item_in_bytes(item));
+ preempt_disable_rt();
v = __this_cpu_dec_return(*p);
t = __this_cpu_read(pcp->stat_threshold);
if (unlikely(v < - t)) {
@@ -459,6 +470,7 @@ void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
node_page_state_add(v - overstep, pgdat, item);
__this_cpu_write(*p, overstep);
}
+ preempt_enable_rt();
}
void __dec_zone_page_state(struct page *page, enum zone_stat_item item)
diff --git a/mm/workingset.c b/mm/workingset.c
index 4a30e4a81..4c92584ca 100644
--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -431,6 +431,8 @@ static struct list_lru shadow_nodes;
void workingset_update_node(struct xa_node *node)
{
+ struct address_space *mapping;
+
/*
* Track non-empty nodes that contain only shadow entries;
* unlink those that contain pages or are being freed.
@@ -439,7 +441,8 @@ void workingset_update_node(struct xa_node *node)
* already where they should be. The list_empty() test is safe
* as node->private_list is protected by the i_pages lock.
*/
- VM_WARN_ON_ONCE(!irqs_disabled()); /* For __inc_lruvec_page_state */
+ mapping = container_of(node->array, struct address_space, i_pages);
+ lockdep_assert_held(&mapping->i_pages.xa_lock);
if (node->count && node->count == node->nr_values) {
if (list_empty(&node->private_list)) {
diff --git a/mm/z3fold.c b/mm/z3fold.c
index f75c638c6..6fdf4774f 100644
--- a/mm/z3fold.c
+++ b/mm/z3fold.c
@@ -623,14 +623,16 @@ static inline void add_to_unbuddied(struct z3fold_pool *pool,
{
if (zhdr->first_chunks == 0 || zhdr->last_chunks == 0 ||
zhdr->middle_chunks == 0) {
- struct list_head *unbuddied = get_cpu_ptr(pool->unbuddied);
-
+ struct list_head *unbuddied;
int freechunks = num_free_chunks(zhdr);
+
+ migrate_disable();
+ unbuddied = this_cpu_ptr(pool->unbuddied);
spin_lock(&pool->lock);
list_add(&zhdr->buddy, &unbuddied[freechunks]);
spin_unlock(&pool->lock);
zhdr->cpu = smp_processor_id();
- put_cpu_ptr(pool->unbuddied);
+ migrate_enable();
}
}
@@ -880,8 +882,9 @@ static inline struct z3fold_header *__z3fold_alloc(struct z3fold_pool *pool,
int chunks = size_to_chunks(size), i;
lookup:
+ migrate_disable();
/* First, try to find an unbuddied z3fold page. */
- unbuddied = get_cpu_ptr(pool->unbuddied);
+ unbuddied = this_cpu_ptr(pool->unbuddied);
for_each_unbuddied_list(i, chunks) {
struct list_head *l = &unbuddied[i];
@@ -899,7 +902,7 @@ lookup:
!z3fold_page_trylock(zhdr)) {
spin_unlock(&pool->lock);
zhdr = NULL;
- put_cpu_ptr(pool->unbuddied);
+ migrate_enable();
if (can_sleep)
cond_resched();
goto lookup;
@@ -913,7 +916,7 @@ lookup:
test_bit(PAGE_CLAIMED, &page->private)) {
z3fold_page_unlock(zhdr);
zhdr = NULL;
- put_cpu_ptr(pool->unbuddied);
+ migrate_enable();
if (can_sleep)
cond_resched();
goto lookup;
@@ -928,7 +931,7 @@ lookup:
kref_get(&zhdr->refcount);
break;
}
- put_cpu_ptr(pool->unbuddied);
+ migrate_enable();
if (!zhdr) {
int cpu;
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index 6079f5625..a928c7136 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -57,6 +57,7 @@
#include <linux/wait.h>
#include <linux/pagemap.h>
#include <linux/fs.h>
+#include <linux/local_lock.h>
#define ZSPAGE_MAGIC 0x58
@@ -77,6 +78,20 @@
#define ZS_HANDLE_SIZE (sizeof(unsigned long))
+#ifdef CONFIG_PREEMPT_RT
+
+struct zsmalloc_handle {
+ unsigned long addr;
+ spinlock_t lock;
+};
+
+#define ZS_HANDLE_ALLOC_SIZE (sizeof(struct zsmalloc_handle))
+
+#else
+
+#define ZS_HANDLE_ALLOC_SIZE (sizeof(unsigned long))
+#endif
+
/*
* Object location (<PFN>, <obj_idx>) is encoded as
* a single (unsigned long) handle value.
@@ -293,6 +308,7 @@ struct zspage {
};
struct mapping_area {
+ local_lock_t lock;
char *vm_buf; /* copy buffer for objects that span pages */
char *vm_addr; /* address of kmap_atomic()'ed pages */
enum zs_mapmode vm_mm; /* mapping mode */
@@ -322,7 +338,7 @@ static void SetZsPageMovable(struct zs_pool *pool, struct zspage *zspage) {}
static int create_cache(struct zs_pool *pool)
{
- pool->handle_cachep = kmem_cache_create("zs_handle", ZS_HANDLE_SIZE,
+ pool->handle_cachep = kmem_cache_create("zs_handle", ZS_HANDLE_ALLOC_SIZE,
0, 0, NULL);
if (!pool->handle_cachep)
return 1;
@@ -346,10 +362,27 @@ static void destroy_cache(struct zs_pool *pool)
static unsigned long cache_alloc_handle(struct zs_pool *pool, gfp_t gfp)
{
- return (unsigned long)kmem_cache_alloc(pool->handle_cachep,
- gfp & ~(__GFP_HIGHMEM|__GFP_MOVABLE));
+ void *p;
+
+ p = kmem_cache_alloc(pool->handle_cachep,
+ gfp & ~(__GFP_HIGHMEM|__GFP_MOVABLE));
+#ifdef CONFIG_PREEMPT_RT
+ if (p) {
+ struct zsmalloc_handle *zh = p;
+
+ spin_lock_init(&zh->lock);
+ }
+#endif
+ return (unsigned long)p;
}
+#ifdef CONFIG_PREEMPT_RT
+static struct zsmalloc_handle *zs_get_pure_handle(unsigned long handle)
+{
+ return (void *)(handle &~((1 << OBJ_TAG_BITS) - 1));
+}
+#endif
+
static void cache_free_handle(struct zs_pool *pool, unsigned long handle)
{
kmem_cache_free(pool->handle_cachep, (void *)handle);
@@ -368,12 +401,18 @@ static void cache_free_zspage(struct zs_pool *pool, struct zspage *zspage)
static void record_obj(unsigned long handle, unsigned long obj)
{
+#ifdef CONFIG_PREEMPT_RT
+ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+ WRITE_ONCE(zh->addr, obj);
+#else
/*
* lsb of @obj represents handle lock while other bits
* represent object value the handle is pointing so
* updating shouldn't do store tearing.
*/
WRITE_ONCE(*(unsigned long *)handle, obj);
+#endif
}
/* zpool driver */
@@ -458,7 +497,10 @@ MODULE_ALIAS("zpool-zsmalloc");
#endif /* CONFIG_ZPOOL */
/* per-cpu VM mapping areas for zspage accesses that cross page boundaries */
-static DEFINE_PER_CPU(struct mapping_area, zs_map_area);
+static DEFINE_PER_CPU(struct mapping_area, zs_map_area) = {
+ /* XXX remove this and use a spin_lock_t in pin_tag() */
+ .lock = INIT_LOCAL_LOCK(lock),
+};
static bool is_zspage_isolated(struct zspage *zspage)
{
@@ -868,7 +910,13 @@ static unsigned long location_to_obj(struct page *page, unsigned int obj_idx)
static unsigned long handle_to_obj(unsigned long handle)
{
+#ifdef CONFIG_PREEMPT_RT
+ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+ return zh->addr;
+#else
return *(unsigned long *)handle;
+#endif
}
static unsigned long obj_to_head(struct page *page, void *obj)
@@ -882,22 +930,46 @@ static unsigned long obj_to_head(struct page *page, void *obj)
static inline int testpin_tag(unsigned long handle)
{
+#ifdef CONFIG_PREEMPT_RT
+ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+ return spin_is_locked(&zh->lock);
+#else
return bit_spin_is_locked(HANDLE_PIN_BIT, (unsigned long *)handle);
+#endif
}
static inline int trypin_tag(unsigned long handle)
{
+#ifdef CONFIG_PREEMPT_RT
+ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+ return spin_trylock(&zh->lock);
+#else
return bit_spin_trylock(HANDLE_PIN_BIT, (unsigned long *)handle);
+#endif
}
static void pin_tag(unsigned long handle) __acquires(bitlock)
{
+#ifdef CONFIG_PREEMPT_RT
+ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+ return spin_lock(&zh->lock);
+#else
bit_spin_lock(HANDLE_PIN_BIT, (unsigned long *)handle);
+#endif
}
static void unpin_tag(unsigned long handle) __releases(bitlock)
{
+#ifdef CONFIG_PREEMPT_RT
+ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+ return spin_unlock(&zh->lock);
+#else
bit_spin_unlock(HANDLE_PIN_BIT, (unsigned long *)handle);
+#endif
}
static void reset_page(struct page *page)
@@ -1302,7 +1374,8 @@ void *zs_map_object(struct zs_pool *pool, unsigned long handle,
class = pool->size_class[class_idx];
off = (class->size * obj_idx) & ~PAGE_MASK;
- area = &get_cpu_var(zs_map_area);
+ local_lock(&zs_map_area.lock);
+ area = this_cpu_ptr(&zs_map_area);
area->vm_mm = mm;
if (off + class->size <= PAGE_SIZE) {
/* this object is contained entirely within a page */
@@ -1356,7 +1429,7 @@ void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
__zs_unmap_object(area, pages, off, class->size);
}
- put_cpu_var(zs_map_area);
+ local_unlock(&zs_map_area.lock);
migrate_read_unlock(zspage);
unpin_tag(handle);
diff --git a/net/Kconfig b/net/Kconfig
index 51a934426..9db79194a 100644
--- a/net/Kconfig
+++ b/net/Kconfig
@@ -280,7 +280,7 @@ config CGROUP_NET_CLASSID
config NET_RX_BUSY_POLL
bool
- default y
+ default y if !PREEMPT_RT
config BQL
bool
diff --git a/net/core/dev.c b/net/core/dev.c
index c49f3d306..5f9b8d26f 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -222,14 +222,14 @@ static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
static inline void rps_lock(struct softnet_data *sd)
{
#ifdef CONFIG_RPS
- spin_lock(&sd->input_pkt_queue.lock);
+ raw_spin_lock(&sd->input_pkt_queue.raw_lock);
#endif
}
static inline void rps_unlock(struct softnet_data *sd)
{
#ifdef CONFIG_RPS
- spin_unlock(&sd->input_pkt_queue.lock);
+ raw_spin_unlock(&sd->input_pkt_queue.raw_lock);
#endif
}
@@ -3054,6 +3054,7 @@ static void __netif_reschedule(struct Qdisc *q)
sd->output_queue_tailp = &q->next_sched;
raise_softirq_irqoff(NET_TX_SOFTIRQ);
local_irq_restore(flags);
+ preempt_check_resched_rt();
}
void __netif_schedule(struct Qdisc *q)
@@ -3116,6 +3117,7 @@ void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
__this_cpu_write(softnet_data.completion_queue, skb);
raise_softirq_irqoff(NET_TX_SOFTIRQ);
local_irq_restore(flags);
+ preempt_check_resched_rt();
}
EXPORT_SYMBOL(__dev_kfree_skb_irq);
@@ -3814,7 +3816,11 @@ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
* This permits qdisc->running owner to get the lock more
* often and dequeue packets faster.
*/
+#ifdef CONFIG_PREEMPT_RT
+ contended = true;
+#else
contended = qdisc_is_running(q);
+#endif
if (unlikely(contended))
spin_lock(&q->busylock);
@@ -4618,6 +4624,7 @@ drop:
rps_unlock(sd);
local_irq_restore(flags);
+ preempt_check_resched_rt();
atomic_long_inc(&skb->dev->rx_dropped);
kfree_skb(skb);
@@ -5047,7 +5054,7 @@ static int netif_rx_internal(struct sk_buff *skb)
struct rps_dev_flow voidflow, *rflow = &voidflow;
int cpu;
- preempt_disable();
+ migrate_disable();
rcu_read_lock();
cpu = get_rps_cpu(skb->dev, skb, &rflow);
@@ -5057,14 +5064,14 @@ static int netif_rx_internal(struct sk_buff *skb)
ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
rcu_read_unlock();
- preempt_enable();
+ migrate_enable();
} else
#endif
{
unsigned int qtail;
- ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
- put_cpu();
+ ret = enqueue_to_backlog(skb, get_cpu_light(), &qtail);
+ put_cpu_light();
}
return ret;
}
@@ -5103,11 +5110,9 @@ int netif_rx_ni(struct sk_buff *skb)
trace_netif_rx_ni_entry(skb);
- preempt_disable();
+ local_bh_disable();
err = netif_rx_internal(skb);
- if (local_softirq_pending())
- do_softirq();
- preempt_enable();
+ local_bh_enable();
trace_netif_rx_ni_exit(err);
return err;
@@ -6585,12 +6590,14 @@ static void net_rps_action_and_irq_enable(struct softnet_data *sd)
sd->rps_ipi_list = NULL;
local_irq_enable();
+ preempt_check_resched_rt();
/* Send pending IPI's to kick RPS processing on remote cpus. */
net_rps_send_ipi(remsd);
} else
#endif
local_irq_enable();
+ preempt_check_resched_rt();
}
static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
@@ -6668,6 +6675,7 @@ void __napi_schedule(struct napi_struct *n)
local_irq_save(flags);
____napi_schedule(this_cpu_ptr(&softnet_data), n);
local_irq_restore(flags);
+ preempt_check_resched_rt();
}
EXPORT_SYMBOL(__napi_schedule);
@@ -11218,6 +11226,7 @@ static int dev_cpu_dead(unsigned int oldcpu)
raise_softirq_irqoff(NET_TX_SOFTIRQ);
local_irq_enable();
+ preempt_check_resched_rt();
#ifdef CONFIG_RPS
remsd = oldsd->rps_ipi_list;
@@ -11231,7 +11240,7 @@ static int dev_cpu_dead(unsigned int oldcpu)
netif_rx_ni(skb);
input_queue_head_incr(oldsd);
}
- while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
+ while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
netif_rx_ni(skb);
input_queue_head_incr(oldsd);
}
@@ -11547,7 +11556,7 @@ static int __init net_dev_init(void)
INIT_WORK(flush, flush_backlog);
- skb_queue_head_init(&sd->input_pkt_queue);
+ skb_queue_head_init_raw(&sd->input_pkt_queue);
skb_queue_head_init(&sd->process_queue);
#ifdef CONFIG_XFRM_OFFLOAD
skb_queue_head_init(&sd->xfrm_backlog);
diff --git a/net/core/gen_estimator.c b/net/core/gen_estimator.c
index 8e582e29a..e51f4854d 100644
--- a/net/core/gen_estimator.c
+++ b/net/core/gen_estimator.c
@@ -42,7 +42,7 @@
struct net_rate_estimator {
struct gnet_stats_basic_packed *bstats;
spinlock_t *stats_lock;
- seqcount_t *running;
+ net_seqlock_t *running;
struct gnet_stats_basic_cpu __percpu *cpu_bstats;
u8 ewma_log;
u8 intvl_log; /* period : (250ms << intvl_log) */
@@ -125,7 +125,7 @@ int gen_new_estimator(struct gnet_stats_basic_packed *bstats,
struct gnet_stats_basic_cpu __percpu *cpu_bstats,
struct net_rate_estimator __rcu **rate_est,
spinlock_t *lock,
- seqcount_t *running,
+ net_seqlock_t *running,
struct nlattr *opt)
{
struct gnet_estimator *parm = nla_data(opt);
@@ -226,7 +226,7 @@ int gen_replace_estimator(struct gnet_stats_basic_packed *bstats,
struct gnet_stats_basic_cpu __percpu *cpu_bstats,
struct net_rate_estimator __rcu **rate_est,
spinlock_t *lock,
- seqcount_t *running, struct nlattr *opt)
+ net_seqlock_t *running, struct nlattr *opt)
{
return gen_new_estimator(bstats, cpu_bstats, rate_est,
lock, running, opt);
diff --git a/net/core/gen_stats.c b/net/core/gen_stats.c
index e491b083b..ef432cea2 100644
--- a/net/core/gen_stats.c
+++ b/net/core/gen_stats.c
@@ -137,7 +137,7 @@ __gnet_stats_copy_basic_cpu(struct gnet_stats_basic_packed *bstats,
}
void
-__gnet_stats_copy_basic(const seqcount_t *running,
+__gnet_stats_copy_basic(net_seqlock_t *running,
struct gnet_stats_basic_packed *bstats,
struct gnet_stats_basic_cpu __percpu *cpu,
struct gnet_stats_basic_packed *b)
@@ -150,15 +150,15 @@ __gnet_stats_copy_basic(const seqcount_t *running,
}
do {
if (running)
- seq = read_seqcount_begin(running);
+ seq = net_seq_begin(running);
bstats->bytes = b->bytes;
bstats->packets = b->packets;
- } while (running && read_seqcount_retry(running, seq));
+ } while (running && net_seq_retry(running, seq));
}
EXPORT_SYMBOL(__gnet_stats_copy_basic);
static int
-___gnet_stats_copy_basic(const seqcount_t *running,
+___gnet_stats_copy_basic(net_seqlock_t *running,
struct gnet_dump *d,
struct gnet_stats_basic_cpu __percpu *cpu,
struct gnet_stats_basic_packed *b,
@@ -204,7 +204,7 @@ ___gnet_stats_copy_basic(const seqcount_t *running,
* if the room in the socket buffer was not sufficient.
*/
int
-gnet_stats_copy_basic(const seqcount_t *running,
+gnet_stats_copy_basic(net_seqlock_t *running,
struct gnet_dump *d,
struct gnet_stats_basic_cpu __percpu *cpu,
struct gnet_stats_basic_packed *b)
@@ -228,7 +228,7 @@ EXPORT_SYMBOL(gnet_stats_copy_basic);
* if the room in the socket buffer was not sufficient.
*/
int
-gnet_stats_copy_basic_hw(const seqcount_t *running,
+gnet_stats_copy_basic_hw(net_seqlock_t *running,
struct gnet_dump *d,
struct gnet_stats_basic_cpu __percpu *cpu,
struct gnet_stats_basic_packed *b)
diff --git a/net/core/sock.c b/net/core/sock.c
index 2e39845d0..6f5d884b3 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -3128,12 +3128,11 @@ void lock_sock_nested(struct sock *sk, int subclass)
if (sk->sk_lock.owned)
__lock_sock(sk);
sk->sk_lock.owned = 1;
- spin_unlock(&sk->sk_lock.slock);
+ spin_unlock_bh(&sk->sk_lock.slock);
/*
* The sk_lock has mutex_lock() semantics here:
*/
mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
- local_bh_enable();
}
EXPORT_SYMBOL(lock_sock_nested);
@@ -3182,12 +3181,11 @@ bool lock_sock_fast(struct sock *sk)
__lock_sock(sk);
sk->sk_lock.owned = 1;
- spin_unlock(&sk->sk_lock.slock);
+ spin_unlock_bh(&sk->sk_lock.slock);
/*
* The sk_lock has mutex_lock() semantics here:
*/
mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
- local_bh_enable();
return true;
}
EXPORT_SYMBOL(lock_sock_fast);
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index cfb4904ee..260c6ae49 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -1276,7 +1276,7 @@ static struct Qdisc *qdisc_create(struct net_device *dev,
rcu_assign_pointer(sch->stab, stab);
}
if (tca[TCA_RATE]) {
- seqcount_t *running;
+ net_seqlock_t *running;
err = -EOPNOTSUPP;
if (sch->flags & TCQ_F_MQROOT) {
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index ec55f306a..920d10ec9 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -578,7 +578,11 @@ struct Qdisc noop_qdisc = {
.ops = &noop_qdisc_ops,
.q.lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.q.lock),
.dev_queue = &noop_netdev_queue,
+#ifdef CONFIG_PREEMPT_RT
+ .running = __SEQLOCK_UNLOCKED(noop_qdisc.running),
+#else
.running = SEQCNT_ZERO(noop_qdisc.running),
+#endif
.busylock = __SPIN_LOCK_UNLOCKED(noop_qdisc.busylock),
.gso_skb = {
.next = (struct sk_buff *)&noop_qdisc.gso_skb,
@@ -890,9 +894,15 @@ struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
lockdep_set_class(&sch->seqlock,
dev->qdisc_tx_busylock ?: &qdisc_tx_busylock);
+#ifdef CONFIG_PREEMPT_RT
+ seqlock_init(&sch->running);
+ lockdep_set_class(&sch->running.lock,
+ dev->qdisc_running_key ?: &qdisc_running_key);
+#else
seqcount_init(&sch->running);
lockdep_set_class(&sch->running,
dev->qdisc_running_key ?: &qdisc_running_key);
+#endif
sch->ops = ops;
sch->flags = ops->static_flags;
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index f56b4df6c..6cb833516 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -422,7 +422,7 @@ void svc_xprt_do_enqueue(struct svc_xprt *xprt)
if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags))
return;
- cpu = get_cpu();
+ cpu = get_cpu_light();
pool = svc_pool_for_cpu(xprt->xpt_server, cpu);
atomic_long_inc(&pool->sp_stats.packets);
@@ -446,7 +446,7 @@ void svc_xprt_do_enqueue(struct svc_xprt *xprt)
rqstp = NULL;
out_unlock:
rcu_read_unlock();
- put_cpu();
+ put_cpu_light();
trace_svc_xprt_do_enqueue(xprt, rqstp);
}
EXPORT_SYMBOL_GPL(svc_xprt_do_enqueue);
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 73f5cbae6..a976e2389 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -2670,7 +2670,8 @@ int __net_init xfrm_state_init(struct net *net)
net->xfrm.state_num = 0;
INIT_WORK(&net->xfrm.state_hash_work, xfrm_hash_resize);
spin_lock_init(&net->xfrm.xfrm_state_lock);
- seqcount_init(&net->xfrm.xfrm_state_hash_generation);
+ seqcount_spinlock_init(&net->xfrm.xfrm_state_hash_generation,
+ &net->xfrm.xfrm_state_lock);
return 0;
out_byspi:
--
2.41.0
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