diff --git a/[refs] b/[refs]
index a9fee2b6d655..b6ff7d475b00 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: e9fbcb42201c862fd6ab45c48ead4f47bb2dea9d
+refs/heads/master: cd1cfc49153ba2bef247e500d8bd4d135193ece9
diff --git a/trunk/fs/btrfs/extent-tree.c b/trunk/fs/btrfs/extent-tree.c
index 44f06201f376..4e1b153b7c47 100644
--- a/trunk/fs/btrfs/extent-tree.c
+++ b/trunk/fs/btrfs/extent-tree.c
@@ -5294,6 +5294,7 @@ static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
 	rb_erase(&head->node.rb_node, &delayed_refs->root);
 
 	delayed_refs->num_entries--;
+	smp_mb();
 	if (waitqueue_active(&root->fs_info->tree_mod_seq_wait))
 		wake_up(&root->fs_info->tree_mod_seq_wait);