From 0099190e7f18e890185e36c5a657e9ce95179bc8 Mon Sep 17 00:00:00 2001
From: zhongtao <zhongtao17@huawei.com>
Date: Fri, 1 Mar 2024 15:04:09 +0800
Subject: [PATCH 17/43] bugfix for the concurrency competition between the
 reuse layer and the creation layer

Signed-off-by: zhongtao <zhongtao17@huawei.com>
---
 src/daemon/modules/image/oci/oci_load.c          | 9 ++++++++-
 src/daemon/modules/image/oci/registry/registry.c | 9 ++++++++-
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/src/daemon/modules/image/oci/oci_load.c b/src/daemon/modules/image/oci/oci_load.c
index 534e2647..85127f35 100644
--- a/src/daemon/modules/image/oci/oci_load.c
+++ b/src/daemon/modules/image/oci/oci_load.c
@@ -680,6 +680,12 @@ static int oci_load_set_layers_info(load_image_t *im, const image_manifest_items
     char *parent_chain_id_sha256 = "";
     char *id = NULL;
     char *parent_chain_id = NULL;
+    // exist_flag is used to mark whether a non-existent layer has been encountered during this layer reuse process.
+    // 1.exist_flag is true if the layers are currently reusable;
+    // 2.exist_flag is false if encounter an uncreated layer that cannot be reused
+    // Prevent concurrent competition between the creation layer function
+    // and the reuse layer function on the im -> layer_of_hold_refs variable
+    bool exist_flag = true;
 
     if (im == NULL || manifest == NULL || dstdir == NULL) {
         ERROR("Invalid input params image or manifest is null");
@@ -761,7 +767,7 @@ static int oci_load_set_layers_info(load_image_t *im, const image_manifest_items
             goto out;
         }
 
-        if (storage_inc_hold_refs(id) == 0) {
+        if (exist_flag && storage_inc_hold_refs(id) == 0) {
             free(im->layer_of_hold_refs);
             im->layer_of_hold_refs = util_strdup_s(id);
             if (parent_chain_id != NULL && storage_dec_hold_refs(parent_chain_id) != 0) {
@@ -781,6 +787,7 @@ static int oci_load_set_layers_info(load_image_t *im, const image_manifest_items
             continue;
         }
 
+        exist_flag = false;
         if (check_and_set_digest_from_tarball(im->layers[i], conf->rootfs->diff_ids[i]) != 0) {
             ERROR("Check layer digest failed");
             ret = -1;
diff --git a/src/daemon/modules/image/oci/registry/registry.c b/src/daemon/modules/image/oci/registry/registry.c
index aed3057a..66fa0076 100644
--- a/src/daemon/modules/image/oci/registry/registry.c
+++ b/src/daemon/modules/image/oci/registry/registry.c
@@ -1516,6 +1516,12 @@ static int fetch_all(pull_descriptor *desc)
     struct layer_list *list = NULL;
     pthread_t tid = 0;
     struct timespec ts = { 0 };
+    // exist_flag is used to mark whether a non-existent layer has been encountered during this layer reuse process.
+    // 1.exist_flag is true if the layers are currently reusable;
+    // 2.exist_flag is false if encounter an uncreated layer that cannot be reused
+    // Prevent concurrent competition between the creation layer function
+    // and the reuse layer function on the im -> layer_of_hold_refs variable
+    bool exist_flag = true;
 
     if (desc == NULL) {
         ERROR("Invalid NULL param");
@@ -1547,7 +1553,7 @@ static int fetch_all(pull_descriptor *desc)
 
         // Skip layer that already exist in local store
         list = storage_layers_get_by_compress_digest(desc->layers[i].digest);
-        if (list != NULL) {
+        if (exist_flag && list != NULL) {
             for (j = 0; j < list->layers_len; j++) {
                 if ((list->layers[j]->parent == NULL && i == 0) ||
                     (parent_chain_id != NULL && list->layers[j]->parent != NULL &&
@@ -1579,6 +1585,7 @@ static int fetch_all(pull_descriptor *desc)
                 continue;
             }
         }
+        exist_flag = false;
 
         // parent_chain_id = NULL means no parent chain match from now on, so no longer need
         // to get layers by compressed digest to reuse layer.
-- 
2.34.1

