btrfs: Use fs_info directly in btrfs_delete_unused_bgs

No need to use root->fs_info in btrfs_delete_unused_bgs(),
use fs_info directly instead.

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index b77ffbc..acf3ed1 100644 (file)
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -10289,7 +10289,7 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
                }
                spin_unlock(&fs_info->unused_bgs_lock);
 
-               mutex_lock(&root->fs_info->delete_unused_bgs_mutex);
+               mutex_lock(&fs_info->delete_unused_bgs_mutex);
 
                /* Don't want to race with allocators so take the groups_sem */
                down_write(&space_info->groups_sem);
@@ -10413,7 +10413,7 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
 end_trans:
                btrfs_end_transaction(trans, root);
 next:
-               mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
+               mutex_unlock(&fs_info->delete_unused_bgs_mutex);
                btrfs_put_block_group(block_group);
                spin_lock(&fs_info->unused_bgs_lock);
        }