On 2020/2/12 下午5:35, Anand Jain wrote:
> On some systems btrfs/179 fails because the check finds that there is
> difference in the qgroup counts.
> 
> So as the intention of the test case is to test any hang like situation
> during heavy snapshot create/delete operation with quota enabled, so
> make sure the qgroup counts are consistent at the end of the test case,
> so to make the check happy.
> 
> Signed-off-by: Anand Jain <anand.jain@oracle.com>
> ---
> v2: Use subvolume sync at the end of the test case.
>     Patch title changed.
> 
>  tests/btrfs/179 | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/tests/btrfs/179 b/tests/btrfs/179
> index 4a24ea419a7e..8795d59c01f8 100755
> --- a/tests/btrfs/179
> +++ b/tests/btrfs/179
> @@ -109,6 +109,15 @@ wait $snapshot_pid
>  kill $delete_pid
>  wait $delete_pid
>  
> +# By the async nature of qgroup tree scan and subvolume delete, the latest
> +# qgroup counts at the time of umount might not be upto date, if it isn't
> +# then the check will report the difference in count. The difference in
> +# qgroup counts are anyway updated in the following mount, so it is not a
> +# real issue that this test case is trying to verify. So make sure the
> +# qgroup counts are in sync before unmount happens.

It could be a little easier. Just btrfs-progs has a bug accounting
qgroups for subvolume being dropped.
Btrfs-progs tends to account more extents than it should be.

The subvolume sync would be a workaround for it.

Despite the commment, it looks good to me.

Thanks,
Qu

> +
> +$BTRFS_UTIL_PROG subvolume sync $SCRATCH_MNT >> $seqres.full
> +
>  # success, all done
>  echo "Silence is golden"
>  
>