Reloc tree doesn't contribute to qgroup numbers, as we have
accounted them at balance time (check replace_path()).
Skip such unneeded subtree trace should reduce some performance
overhead.
Signed-off-by: Qu Wenruo <wqu@xxxxxxxx>
---
fs/btrfs/extent-tree.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index de6f75f5547b..4588153f414c 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -8643,7 +8643,13 @@ static noinline int do_walk_down(struct btrfs_trans_handle *trans,
parent = 0;
}
- if (need_account) {
+ /*
+ * Tree reloc tree doesn't contribute to qgroup numbers, and
+ * we have already accounted them at merge time (replace_path),
+ * thus we could skip expensive subtree trace here.
+ */
+ if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID &&
+ need_account) {
ret = btrfs_qgroup_trace_subtree(trans, next,
generation, level - 1);
if (ret) {
--
2.18.0
