[PATCH 4/5] ceph: fix improper use of smp_mb__before_atomic()

[Andrea Parri]

This barrier only applies to the read-modify-write operations; in
particular, it does not apply to the atomic64_set() primitive.

Replace the barrier with an smp_mb().

Fixes: fdd4e15838e59 ("ceph: rework dcache readdir")
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: "Paul E. McKenney" <paulmck@xxxxxxxxxxxxx>
Reported-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Signed-off-by: Andrea Parri <andrea.parri@xxxxxxxxxxxxxxxxxxxx>
Cc: "Yan, Zheng" <zyan@xxxxxxxxxx>
Cc: Sage Weil <sage@xxxxxxxxxx>
Cc: Ilya Dryomov <idryomov@xxxxxxxxx>
Cc: ceph-devel@xxxxxxxxxxxxxxx
---
 fs/ceph/super.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 16c03188578ea..b5c782e6d62f1 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -541,7 +541,7 @@ static inline void __ceph_dir_set_complete(struct ceph_inode_info *ci,
 					   long long release_count,
 					   long long ordered_count)
 {
-	smp_mb__before_atomic();
+	smp_mb();
 	atomic64_set(&ci->i_complete_seq[0], release_count);
 	atomic64_set(&ci->i_complete_seq[1], ordered_count);
 }
-- 
2.7.4