Commit 194ab0bc authored by Josef Bacik's avatar Josef Bacik Committed by David Sterba
Browse files

btrfs: breakout empty head cleanup to a helper 



Move this code out to a helper function to further simplivy
__btrfs_run_delayed_refs.

Signed-off-by: default avatarJosef Bacik <jbacik@fb.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent b00e6250

fs/btrfs/extent-tree.c

+45 −34
Original line number Diff line number Diff line
@@ -2605,6 +2605,43 @@ static int cleanup_extent_op(struct btrfs_trans_handle *trans, 
	return ret ? ret : 1;

}



static int cleanup_ref_head(struct btrfs_trans_handle *trans,

			    struct btrfs_fs_info *fs_info,

			    struct btrfs_delayed_ref_head *head)

{

	struct btrfs_delayed_ref_root *delayed_refs;

	int ret;



	delayed_refs = &trans->transaction->delayed_refs;



	ret = cleanup_extent_op(trans, fs_info, head);

	if (ret < 0) {

		unselect_delayed_ref_head(delayed_refs, head);

		btrfs_debug(fs_info, "run_delayed_extent_op returned %d", ret);

		return ret;

	} else if (ret) {

		return ret;

	}



	/*

	 * Need to drop our head ref lock and re-acquire the delayed ref lock

	 * and then re-check to make sure nobody got added.

	 */

	spin_unlock(&head->lock);

	spin_lock(&delayed_refs->lock);

	spin_lock(&head->lock);

	if (!list_empty(&head->ref_list) || head->extent_op) {

		spin_unlock(&head->lock);

		spin_unlock(&delayed_refs->lock);

		return 1;

	}

	head->node.in_tree = 0;

	delayed_refs->num_heads--;

	rb_erase(&head->href_node, &delayed_refs->href_root);

	spin_unlock(&delayed_refs->lock);

	return 0;

}



/*

 * Returns 0 on success or if called with an already aborted transaction.

 * Returns -ENOMEM or -EIO on failure and will abort the transaction.
@@ -2686,47 +2723,21 @@ static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, 
		}



		if (!ref) {





			/* All delayed refs have been processed, Go ahead

			 * and send the head node to run_one_delayed_ref,

			 * so that any accounting fixes can happen

			 */

			ref = &locked_ref->node;



			ret = cleanup_extent_op(trans, fs_info, locked_ref);

			if (ret < 0) {

				unselect_delayed_ref_head(delayed_refs,

							  locked_ref);

				btrfs_debug(fs_info,

					    "run_delayed_extent_op returned %d",

					    ret);

				return ret;

			} else if (ret > 0) {

			ret = cleanup_ref_head(trans, fs_info, locked_ref);

			if (ret > 0 ) {

				/* We dropped our lock, we need to loop. */

				ret = 0;

				continue;

			} else if (ret) {

				return ret;

			}



			/*

			 * Need to drop our head ref lock and re-acquire the

			 * delayed ref lock and then re-check to make sure

			 * nobody got added.

			 * All delayed refs have been processed, Go ahead and

			 * send the head node to run_one_delayed_ref, so that

			 * any accounting fixes can happen

			 */

			spin_unlock(&locked_ref->lock);

			spin_lock(&delayed_refs->lock);

			spin_lock(&locked_ref->lock);

			if (!list_empty(&locked_ref->ref_list) ||

			    locked_ref->extent_op) {

				spin_unlock(&locked_ref->lock);

				spin_unlock(&delayed_refs->lock);

				continue;

			}

			ref->in_tree = 0;

			delayed_refs->num_heads--;

			rb_erase(&locked_ref->href_node,

				 &delayed_refs->href_root);

			spin_unlock(&delayed_refs->lock);

			ref = &locked_ref->node;

		} else {

			actual_count++;

			ref->in_tree = 0;