Btrfs: Fix snapshot deletion to release the alloc_mutex much more often.

This lowers the impact of snapshot deletion on the rest of the FS.

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index fd68601b60b1..5edbcc09b3cc 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -1255,7 +1255,7 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
         lowest_level = p->lowest_level;
         WARN_ON(lowest_level && ins_len);
         WARN_ON(p->nodes[0] != NULL);
-        WARN_ON(root == root->fs_info->extent_root &&
+        WARN_ON(cow && root == root->fs_info->extent_root &&
                 !mutex_is_locked(&root->fs_info->alloc_mutex));
         WARN_ON(root == root->fs_info->chunk_root &&
                 !mutex_is_locked(&root->fs_info->chunk_mutex));