On 17.10.19 г. 5:38 ч., Qu Wenruo wrote:
> [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]>
Reviewed-by: Nikolay Borisov <[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);
> }
>
