From d1980131ca7f0776542f776ceb777cd01eb983e2 Mon Sep 17 00:00:00 2001 From: David Sterba Date: Fri, 16 Mar 2018 02:39:40 +0100 Subject: btrfs: update barrier in should_cow_block Once there was a simple int force_cow that was used with the plain barriers, and then converted to a bit, so we should use the appropriate barrier helper. Other variables in the complex if condition do not depend on a barrier, so we should be fine in case the atomic barrier becomes a no-op. Signed-off-by: David Sterba --- fs/btrfs/ctree.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/btrfs') diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 7c8faeb868f4..a2c9d21176e2 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -1441,8 +1441,8 @@ static inline int should_cow_block(struct btrfs_trans_handle *trans, if (btrfs_is_testing(root->fs_info)) return 0; - /* ensure we can see the force_cow */ - smp_rmb(); + /* Ensure we can see the FORCE_COW bit */ + smp_mb__before_atomic(); /* * We do not need to cow a block if -- cgit v1.2.3-55-g7522