Merge branch 'for-linus-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mason...

[firefly-linux-kernel-4.4.55.git] / fs / btrfs / delayed-inode.c

diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
index a2ae42720a6afe92701de402b837d56dd66d03b4..e0941fbb913c2e99740b9df34d06efbc8cffdea1 100644 (file)
--- a/fs/btrfs/delayed-inode.c
+++ b/fs/btrfs/delayed-inode.c
@@ -463,6 +463,10 @@ static int __btrfs_add_delayed_deletion_item(struct btrfs_delayed_node *node,
 static void finish_one_item(struct btrfs_delayed_root *delayed_root)
 {
        int seq = atomic_inc_return(&delayed_root->items_seq);
+
+       /*
+        * atomic_dec_return implies a barrier for waitqueue_active
+        */
        if ((atomic_dec_return(&delayed_root->items) <
            BTRFS_DELAYED_BACKGROUND || seq % BTRFS_DELAYED_BATCH == 0) &&
            waitqueue_active(&delayed_root->wait))