Re: [PATCH 2/3] fstests: btrfs/022: Match qgroup id more correctly

[Nikolay Borisov <nborisov@suse.com>]

On 7.02.20 г. 3:59 ч., Qu Wenruo wrote:
> [BUG]
> Btrfs/022 sometimes fails with snapshot's reference mismatch with its
> source.
> 
> [CAUSE]
> Since commit fd0830929573 ("fsstress: add the ability to create
> snapshots") adds the ability for fsstress to create/delete snapshot and
> subvolumes, fsstress will create new subvolumes under test dir.
> 
> For example, we could have the following subvolumes created by fsstress:
> subvol a id=256
> subvol b id=306
> qgroupid         rfer         excl
> --------         ----         ----
> 0/5             16384        16384
> 0/256        13914112        16384
> ...
> 0/263         3080192      2306048 		<< 2 *306* 048
> ...
> 0/306        13914112        16384 		<< 0/ *306
> 
> So when we're greping for subvolid 306, it matches qgroup 0/263 first,
> which has difference size, and caused false alert.
> 
> [FIX]
> Instead of greping "$subvolid" blindly, now grep "0/$subvolid" to catch
> qgroupid correctly, without hitting rfer/excl values.

That 0/ can it ever be a number different than 0, if so a more correct
regular expression should be:
grep "[[:digit:]]/306"  ?


> 
> Suggested-by: Josef Bacik <josef@toxicpanda.com>
> Signed-off-by: Qu Wenruo <wqu@suse.com>
> ---
>  tests/btrfs/022 | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/tests/btrfs/022 b/tests/btrfs/022
> index 5348d3ed..3e729852 100755
> --- a/tests/btrfs/022
> +++ b/tests/btrfs/022
> @@ -49,10 +49,10 @@ _basic_test()
>  
>  	# the shared values of both the original subvol and snapshot should
>  	# match
> -	a_shared=$($BTRFS_UTIL_PROG qgroup show $units $SCRATCH_MNT | grep $subvolid)
> +	a_shared=$($BTRFS_UTIL_PROG qgroup show $units $SCRATCH_MNT | grep "0/$subvolid")
>  	a_shared=$(echo $a_shared | awk '{ print $2 }')
>  	subvolid=$(_btrfs_get_subvolid $SCRATCH_MNT b)
> -	b_shared=$($BTRFS_UTIL_PROG qgroup show $units $SCRATCH_MNT | grep $subvolid)
> +	b_shared=$($BTRFS_UTIL_PROG qgroup show $units $SCRATCH_MNT | grep "0/$subvolid")
>  	b_shared=$(echo $b_shared | awk '{ print $2 }')
>  	[ $b_shared -eq $a_shared ] || _fail "shared values don't match"
>  }
> @@ -68,12 +68,12 @@ _rescan_test()
>  	run_check $FSSTRESS_PROG -d $SCRATCH_MNT/a -w -p 1 -n 2000 \
>  		$FSSTRESS_AVOID
>  	sync
> -	output=$($BTRFS_UTIL_PROG qgroup show $units $SCRATCH_MNT | grep $subvolid)
> +	output=$($BTRFS_UTIL_PROG qgroup show $units $SCRATCH_MNT | grep "0/$subvolid")
>  	echo $output >> $seqres.full
>  	refer=$(echo $output | awk '{ print $2 }')
>  	excl=$(echo $output | awk '{ print $3 }')
>  	_run_btrfs_util_prog quota rescan -w $SCRATCH_MNT
> -	output=$($BTRFS_UTIL_PROG qgroup show $units $SCRATCH_MNT | grep $subvolid)
> +	output=$($BTRFS_UTIL_PROG qgroup show $units $SCRATCH_MNT | grep "0/$subvolid")
>  	echo $output >> $seqres.full
>  	[ $refer -eq $(echo $output | awk '{ print $2 }') ] || \
>  		_fail "reference values don't match after rescan"
>