From: Huaisheng Ye <yehs1@xxxxxxxxxx> In functions writecache_discard and writecache_find_entry, there is high probablity that the pointer of structure rb_node doesn't equal to NULL. Add unlikly for the pointer node. Signed-off-by: Huaisheng Ye <yehs1@xxxxxxxxxx> --- drivers/md/dm-writecache.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c index 5b4d1c1..cfbbfbc 100644 --- a/drivers/md/dm-writecache.c +++ b/drivers/md/dm-writecache.c @@ -571,7 +571,7 @@ static struct wc_entry *writecache_find_entry(struct dm_writecache *wc, node = rb_prev(&e->rb_node); else node = rb_next(&e->rb_node); - if (!node) + if (unlikely(!node)) return e; e2 = container_of(node, struct wc_entry, rb_node); if (read_original_sector(wc, e2) != block) @@ -804,7 +804,7 @@ static void writecache_discard(struct dm_writecache *wc, sector_t start, sector_ writecache_free_entry(wc, e); } - if (!node) + if (unlikely(!node)) break; e = container_of(node, struct wc_entry, rb_node); -- 1.8.3.1 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel