Btrfs: convert smp_mb__{before,after}_clear_bit

The new call is smp_mb__{before,after}_atomic.  The __ gives us extra
protection from the atomic rays.

Signed-off-by: Chris Mason <clm@fb.com>

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 1c54e2e..9630f10 100644 (file)
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -290,7 +290,7 @@ static int record_root_in_trans(struct btrfs_trans_handle *trans,
                 * done before we pop in the zero below
                 */
                btrfs_init_reloc_root(trans, root);
-               smp_mb__before_clear_bit();
+               smp_mb__before_atomic();
                clear_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state);
        }
        return 0;
@@ -1060,7 +1060,7 @@ static noinline int commit_fs_roots(struct btrfs_trans_handle *trans,
 
                        /* see comments in should_cow_block() */
                        clear_bit(BTRFS_ROOT_FORCE_COW, &root->state);
-                       smp_mb__after_clear_bit();
+                       smp_mb__after_atomic();
 
                        if (root->commit_root != root->node) {
                                list_add_tail(&root->dirty_list,