Re: [PATCH 3/6] xfs/531: Fix test to execute in multi-block directory config

["Darrick J. Wong" <djwong@kernel.org>]

On Thu, Mar 25, 2021 at 07:38:54PM +0530, Chandan Babu R wrote:
> xfs/531 attempts to create $testfile after reduce_max_iextents error tag is
> injected. Creation of $testfile fails when using a multi-block directory test
> configuration because,
> 1. A directory can have a pseudo maximum extent count of 10.
> 2. In the worst case a directory entry creation operation can consume
>    (XFS_DA_NODE_MAXDEPTH + 1 + 1) * (Nr fs blocks in a single directory block)
>    extents.
>    With 1k fs block size and 4k directory block size, this evaluates to,
>    (5 + 1 + 1) * 4
>    = 7 * 4
>    = 28
>    > 10 (Pseudo maximum inode extent count).
> 
> This commit fixes the issue by creating $testfile before injecting
> reduce_max_iextents error tag.
> 
> Reported-by: Darrick J. Wong <djwong@kernel.org>
> Suggested-by: Darrick J. Wong <djwong@kernel.org>
> Signed-off-by: Chandan Babu R <chandanrlinux@gmail.com>

Much better,
Reviewed-by: Darrick J. Wong <djwong@kernel.org>

--D

> ---
>  tests/xfs/531     | 11 ++++++++---
>  tests/xfs/531.out |  9 ++++++++-
>  2 files changed, 16 insertions(+), 4 deletions(-)
> 
> diff --git a/tests/xfs/531 b/tests/xfs/531
> index caec7848..935c52b0 100755
> --- a/tests/xfs/531
> +++ b/tests/xfs/531
> @@ -49,13 +49,15 @@ nr_blks=30
>  
>  testfile=$SCRATCH_MNT/testfile
>  
> -echo "Inject reduce_max_iextents error tag"
> -_scratch_inject_error reduce_max_iextents 1
> -
>  for op in fpunch finsert fcollapse fzero; do
>  	echo "* $op regular file"
>  
>  	echo "Create \$testfile"
> +	touch $testfile
> +
> +	echo "Inject reduce_max_iextents error tag"
> +	_scratch_inject_error reduce_max_iextents 1
> +
>  	$XFS_IO_PROG -f -s \
>  		     -c "pwrite -b $((nr_blks * bsize)) 0 $((nr_blks * bsize))" \
>  		     $testfile  >> $seqres.full
> @@ -75,6 +77,9 @@ for op in fpunch finsert fcollapse fzero; do
>  		exit 1
>  	fi
>  
> +	echo "Disable reduce_max_iextents error tag"
> +	_scratch_inject_error reduce_max_iextents 0
> +
>  	rm $testfile
>  done
>  
> diff --git a/tests/xfs/531.out b/tests/xfs/531.out
> index f85776c9..6ac90787 100644
> --- a/tests/xfs/531.out
> +++ b/tests/xfs/531.out
> @@ -1,19 +1,26 @@
>  QA output created by 531
>  Format and mount fs
> -Inject reduce_max_iextents error tag
>  * fpunch regular file
>  Create $testfile
> +Inject reduce_max_iextents error tag
>  fpunch alternating blocks
>  Verify $testfile's extent count
> +Disable reduce_max_iextents error tag
>  * finsert regular file
>  Create $testfile
> +Inject reduce_max_iextents error tag
>  finsert alternating blocks
>  Verify $testfile's extent count
> +Disable reduce_max_iextents error tag
>  * fcollapse regular file
>  Create $testfile
> +Inject reduce_max_iextents error tag
>  fcollapse alternating blocks
>  Verify $testfile's extent count
> +Disable reduce_max_iextents error tag
>  * fzero regular file
>  Create $testfile
> +Inject reduce_max_iextents error tag
>  fzero alternating blocks
>  Verify $testfile's extent count
> +Disable reduce_max_iextents error tag
> -- 
> 2.29.2
>