diff mbox series

generic/587: fix rounding error in quota/stat block comparison

Message ID 20200318150142.GA256607@magnolia (mailing list archive)
State New, archived
Headers show
Series generic/587: fix rounding error in quota/stat block comparison | expand

Commit Message

Darrick J. Wong March 18, 2020, 3:01 p.m. UTC
From: Darrick J. Wong <darrick.wong@oracle.com>

It turns out that repquota (which reports in units of 1k blocks) reports
rounded up numbers when the fs blocksize is 512 bytes.  However, xfs_io
stat always reports block counts in units of 512 bytes.  If the number
of (512b) file blocks is not an even number, the "$3 / 2" expression
will round down, causing the test to fail.  Round up to the nearest 1k
to match repquota's behavior.

Reported-by: zlang@redhat.com
Fixes: 6b04ed05456fc6c ("generic: test unwritten extent conversion extent mapping quota accounting")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 tests/generic/587 |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Zorro Lang March 18, 2020, 7:35 p.m. UTC | #1
On Wed, Mar 18, 2020 at 08:01:42AM -0700, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
> 
> It turns out that repquota (which reports in units of 1k blocks) reports
> rounded up numbers when the fs blocksize is 512 bytes.  However, xfs_io
> stat always reports block counts in units of 512 bytes.  If the number
> of (512b) file blocks is not an even number, the "$3 / 2" expression
> will round down, causing the test to fail.  Round up to the nearest 1k
> to match repquota's behavior.
> 
> Reported-by: zlang@redhat.com
> Fixes: 6b04ed05456fc6c ("generic: test unwritten extent conversion extent mapping quota accounting")
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> ---

I've tested this patch. It's good to me. If we can add a simple comment before
doing "($3 + 1)", to explain why we need a "blocks + 1" at here, that would be
better for others read this code.

Reviewed-by: Zorro Lang <zlang@redhat.com>

>  tests/generic/587 |    3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/tests/generic/587 b/tests/generic/587
> index 7b07d07d..2ffa367d 100755
> --- a/tests/generic/587
> +++ b/tests/generic/587
> @@ -57,7 +57,8 @@ check_quota_accounting()
>  {
>  	$XFS_IO_PROG -c stat $testfile > $tmp.out
>  	cat $tmp.out >> $seqres.full
> -	local stat_blocks=$(grep 'stat.blocks' $tmp.out | awk '{print $3 / 2}')
> +	local stat_blocks=$(grep 'stat.blocks' $tmp.out | \
> +		awk '{printf("%d\n", ($3 + 1) / 2);}')
>  
>  	_report_quota_blocks $SCRATCH_MNT > $tmp.out
>  	cat $tmp.out >> $seqres.full
>
diff mbox series

Patch

diff --git a/tests/generic/587 b/tests/generic/587
index 7b07d07d..2ffa367d 100755
--- a/tests/generic/587
+++ b/tests/generic/587
@@ -57,7 +57,8 @@  check_quota_accounting()
 {
 	$XFS_IO_PROG -c stat $testfile > $tmp.out
 	cat $tmp.out >> $seqres.full
-	local stat_blocks=$(grep 'stat.blocks' $tmp.out | awk '{print $3 / 2}')
+	local stat_blocks=$(grep 'stat.blocks' $tmp.out | \
+		awk '{printf("%d\n", ($3 + 1) / 2);}')
 
 	_report_quota_blocks $SCRATCH_MNT > $tmp.out
 	cat $tmp.out >> $seqres.full