Re: [PATCH v2 4/4] xfs/21{6,7} Use default -l concurrency=0 on mkfs.xfs that supports it

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

On Thu, May 14, 2026 at 01:39:15PM +0200, Lukas Herbolt wrote:
> The XFS concurrency optimization breaks the log sizing check on
> systems with non-rotational disks and high amount of CPUs. Default to
> the old behavior with -l concurrency=0 and with -d concurrency=0.
> 
> Signed-off-by: Lukas Herbolt <lukas@herbolt.com>
> ---
>  changes v2:
> 	use default mkfs.xfs for scratch device
> 	remove the double check -l/-d as those were introduced together

Yeah, sorry about breaking that. :/
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>

--D

>  tests/xfs/216 | 6 +++++-
>  tests/xfs/217 | 7 ++++++-
>  2 files changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/tests/xfs/216 b/tests/xfs/216
> index 091c11d08642..0148e7f4de3e 100755
> --- a/tests/xfs/216
> +++ b/tests/xfs/216
> @@ -22,13 +22,17 @@ _cleanup()
>  
>  _require_scratch
>  _scratch_mkfs_xfs >/dev/null 2>&1
> +if _scratch_mkfs_xfs_supports_concurrency -l >> $seqres.full 2>&1; then
> +	loop_mkfs_opts="-l concurrency=0"
> +else
> +	loop_mkfs_opts=""
> +fi
>  _scratch_mount
>  
>  _require_loop
>  LOOP_IMG=$SCRATCH_MNT/test_fs
>  LOOP_MNT=$SCRATCH_MNT/test_fs_dir
>  
> -loop_mkfs_opts=
>  $MKFS_XFS_PROG 2>&1 | grep -q rmapbt && \
>  	loop_mkfs_opts="$loop_mkfs_opts -m rmapbt=0"
>  $MKFS_XFS_PROG 2>&1 | grep -q reflink && \
> diff --git a/tests/xfs/217 b/tests/xfs/217
> index dae6ce55f475..23aae842d1fb 100755
> --- a/tests/xfs/217
> +++ b/tests/xfs/217
> @@ -21,6 +21,11 @@ _cleanup()
>  
>  _require_scratch
>  _scratch_mkfs_xfs >/dev/null 2>&1
> +if _scratch_mkfs_xfs_supports_concurrency -l >> $seqres.full 2>&1; then
> +	loop_mkfs_opts="-l concurrency=0 -d concurrency=0"
> +else
> +	loop_mkfs_opts=""
> +fi
>  _scratch_mount
>  # 16T mkfs requires a bit over 2G free
>  _require_fs_space $SCRATCH_MNT 2202000
> @@ -34,7 +39,7 @@ _do_mkfs()
>  	for i in $*; do
>  		echo -n "fssize=${i}g "
>  		$MKFS_XFS_PROG -f -b size=4096 -l version=2 \
> -			-d size=${i}g $loop_dev |grep log
> +			-d size=${i}g $loop_dev $loop_mkfs_opts |grep log
>  		_mount $loop_dev $LOOP_MNT
>  		echo "test write" > $LOOP_MNT/test
>  		_unmount $LOOP_MNT > /dev/null 2>&1
> -- 
> 2.54.0
> 
>