[BUG]
For btrfs:qgroup_meta_reserve event, the trace event can output garbage:
qgroup_meta_reserve: 9c7f6acc-b342-4037-bc47-7f6e4d2232d7: refroot=5(FS_TREE) 
type=DATA diff=2

The diff should always be alinged to sector size (4k), so there is
definitely something wrong.

[CAUSE]
For the wrong @diff, it's caused by wrong parameter order.
The correct parameters are:
  struct btrfs_root, s64 diff, int type.

However the parameters used are:
  struct btrfs_root, int type, s64 diff.

[FIX]
Fix the super stupid bug.

Fixes: 4ee0d8832c2e ("btrfs: qgroup: Update trace events for metadata 
reservation")
Signed-off-by: Qu Wenruo <[email protected]>
---
 fs/btrfs/qgroup.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index c4bb69941c77..3ad151655eb8 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -3629,7 +3629,7 @@ int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, 
int num_bytes,
                return 0;
 
        BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
-       trace_qgroup_meta_reserve(root, type, (s64)num_bytes);
+       trace_qgroup_meta_reserve(root, (s64)num_bytes, type);
        ret = qgroup_reserve(root, num_bytes, enforce, type);
        if (ret < 0)
                return ret;
@@ -3676,7 +3676,7 @@ void __btrfs_qgroup_free_meta(struct btrfs_root *root, 
int num_bytes,
         */
        num_bytes = sub_root_meta_rsv(root, num_bytes, type);
        BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
-       trace_qgroup_meta_reserve(root, type, -(s64)num_bytes);
+       trace_qgroup_meta_reserve(root, -(s64)num_bytes, type);
        btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid,
                                  num_bytes, type);
 }
-- 
2.23.0

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