Btrfs: fix wrong block group in trace during the free space allocation

We allocate the free space from the former block group, not the current
one, so should use the former one to output the trace information.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index b55a4fd13ecc6c41c81a029c5f68c6f36fd9f14d..73b55d94b95301a9bdce64964bf6757d202d094d 100644 (file)
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -6323,7 +6323,8 @@ have_block_group:
                                /* we have a block, we're done */
                                spin_unlock(&last_ptr->refill_lock);
                                trace_btrfs_reserve_extent_cluster(root,
-                                       block_group, search_start, num_bytes);
+                                               used_block_group,
+                                               search_start, num_bytes);
                                if (used_block_group != block_group) {
                                        btrfs_put_block_group(block_group);
                                        block_group = used_block_group;