Btrfs: fix unreleased path in btrfs_orphan_cleanup()

When we did stress test for the space relocation, the deadlock happened.
By debugging, We found it was caused by the carelessness that we forgot
to unlock the read lock of the extent buffers in btrfs_orphan_cleanup()
before we end the transaction handle, so the transaction commit task waited
the task, which called btrfs_orphan_cleanup(), to unlock the extent buffer,
but that task waited the commit task to end the transaction commit, and
the deadlock happened. Fix it.

Signed-ff-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
(cherry picked from commit 3254c87618354e58fa2a7b375c6664f567480c33)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 396104d39df2539889b5d69aed2c4a24f5d620c8..465eeb199bf3c71b7a57284be81e851b9653ff6c 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2201,6 +2201,9 @@ int btrfs_orphan_cleanup(struct btrfs_root *root)
                if (ret)
                        goto out;
        }
+       /* release the path since we're done with it */
+       btrfs_release_path(path);
+
        root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE;
 
        if (root->orphan_block_rsv)