mysql5/mysql-5.7.27/include/my_thread_os_id.h

99 lines
2.8 KiB
C

/* Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA */
/**
@file include/my_thread_os_id.h
Portable wrapper for gettid().
*/
#ifndef MY_THREAD_OS_ID_INCLUDED
#define MY_THREAD_OS_ID_INCLUDED
#include "my_global.h" /* my_bool */
#ifndef _WIN32
#include <sys/types.h> /* pid_t */
#include <sys/syscall.h> /* SYS_gettid */
#include <unistd.h> /* syscall */
#include <pthread.h> /* pthread_self */
#endif
#ifdef HAVE_PTHREAD_GETTHREADID_NP
#include <pthread_np.h> /* pthread_getthreadid_np() */
#endif /* HAVE_PTHREAD_GETTHREADID_NP */
#ifdef HAVE_PTHREAD_THREADID_NP
#include <pthread.h>
#endif /* HAVE_PTHREAD_THREADID_NP */
C_MODE_START
typedef unsigned long long my_thread_os_id_t;
/**
Return the operating system thread id.
With Linux, threads have:
- an internal id, @c pthread_self(), visible in process
- an external id, @c gettid(), visible in the operating system,
for example with perf in linux.
This helper returns the underling operating system thread id.
*/
static inline my_thread_os_id_t my_thread_os_id()
{
#ifdef HAVE_PTHREAD_THREADID_NP
/*
macOS.
Be careful to use this version first, and to not use SYS_gettid on macOS,
as SYS_gettid has a different meaning compared to linux gettid().
*/
uint64_t tid64;
pthread_threadid_np(nullptr, &tid64);
return (pid_t)tid64;
#else
#ifdef HAVE_SYS_GETTID
/*
Linux.
See man gettid
See GLIBC Bug 6399 - gettid() should have a wrapper
https://sourceware.org/bugzilla/show_bug.cgi?id=6399
*/
return syscall(SYS_gettid);
#else
#ifdef _WIN32
/* Windows */
return GetCurrentThreadId();
#else
#ifdef HAVE_PTHREAD_GETTHREADID_NP
/* FreeBSD 10.2 */
return pthread_getthreadid_np();
#else
#ifdef HAVE_INTEGER_PTHREAD_SELF
/* Unknown platform, fallback. */
return pthread_self();
#else
/* Feature not available. */
return 0;
#endif /* HAVE_INTEGER_PTHREAD_SELF */
#endif /* HAVE_PTHREAD_GETTHREADID_NP */
#endif /* _WIN32 */
#endif /* HAVE_SYS_GETTID */
#endif /* HAVE_SYS_THREAD_SELFID */
}
C_MODE_END
#endif /* MY_THREAD_OS_ID_INCLUDED */