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The x86 CMPXCHG instruction returns success in the ZF flag, so this change saves a compare after CMPXCHG. No functional change intended. Signed-off-by: Uros Bizjak Cc: Alexander Viro Cc: Christian Brauner Cc: Jan Kara --- fs/super.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/fs/super.c b/fs/super.c index 7f876f32343a..e91718017701 100644 --- a/fs/super.c +++ b/fs/super.c @@ -2318,13 +2318,15 @@ int sb_init_dio_done_wq(struct super_block *sb) sb->s_id); if (!wq) return -ENOMEM; + + old = NULL; /* * This has to be atomic as more DIOs can race to create the workqueue */ - old = cmpxchg(&sb->s_dio_done_wq, NULL, wq); - /* Someone created workqueue before us? Free ours... */ - if (old) + if (!try_cmpxchg(&sb->s_dio_done_wq, &old, wq)) { + /* Someone created workqueue before us? Free ours... */ destroy_workqueue(wq); + } return 0; } EXPORT_SYMBOL_GPL(sb_init_dio_done_wq); -- 2.50.1