Btrfs: run delayed refs first when out of space

Running delayed refs is faster than running delalloc, so lets do that first
to try and reclaim space.  This makes my fs_mark test about 20% faster.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 395e222e39ab3334a3f7bcbdb3378c8f4b7d973e..3270b1087850d8e2cd61b9bbcf41aaafb6b909ec 100644 (file)
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3817,10 +3817,10 @@ commit:
 }
 
 enum flush_state {
-       FLUSH_DELALLOC          =       1,
-       FLUSH_DELALLOC_WAIT     =       2,
-       FLUSH_DELAYED_ITEMS_NR  =       3,
-       FLUSH_DELAYED_ITEMS     =       4,
+       FLUSH_DELAYED_ITEMS_NR  =       1,
+       FLUSH_DELAYED_ITEMS     =       2,
+       FLUSH_DELALLOC          =       3,
+       FLUSH_DELALLOC_WAIT     =       4,
        ALLOC_CHUNK             =       5,
        COMMIT_TRANS            =       6,
 };
@@ -3834,11 +3834,6 @@ static int flush_space(struct btrfs_root *root,
        int ret = 0;
 
        switch (state) {
-       case FLUSH_DELALLOC:
-       case FLUSH_DELALLOC_WAIT:
-               shrink_delalloc(root, num_bytes, orig_bytes,
-                               state == FLUSH_DELALLOC_WAIT);
-               break;
        case FLUSH_DELAYED_ITEMS_NR:
        case FLUSH_DELAYED_ITEMS:
                if (state == FLUSH_DELAYED_ITEMS_NR) {
@@ -3859,6 +3854,11 @@ static int flush_space(struct btrfs_root *root,
                ret = btrfs_run_delayed_items_nr(trans, root, nr);
                btrfs_end_transaction(trans, root);
                break;
+       case FLUSH_DELALLOC:
+       case FLUSH_DELALLOC_WAIT:
+               shrink_delalloc(root, num_bytes, orig_bytes,
+                               state == FLUSH_DELALLOC_WAIT);
+               break;
        case ALLOC_CHUNK:
                trans = btrfs_join_transaction(root);
                if (IS_ERR(trans)) {
@@ -3903,7 +3903,7 @@ static int reserve_metadata_bytes(struct btrfs_root *root,
        struct btrfs_space_info *space_info = block_rsv->space_info;
        u64 used;
        u64 num_bytes = orig_bytes;
-       int flush_state = FLUSH_DELALLOC;
+       int flush_state = FLUSH_DELAYED_ITEMS_NR;
        int ret = 0;
        bool flushing = false;
        bool committed = false;