Re: [PATCH 4/4] xfs/216 xfs/217 Use default -l conccurency=0 on mkfs.xfs that supports it

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

On Thu, Apr 30, 2026 at 03:13:22PM +0200, Lukas Herbolt wrote:
> The XFS conccurency optimalization breaks the log sizing check on

"concurrency optimization"

> systems with non-rotational disks and high amount of CPUs. Default to
> the old behavior with -l conccurency=0 and with -d concurrency=0.

"-l concurrency=0"

> Signed-off-by: Lukas Herbolt <lukas@herbolt.com>
> ---
>  tests/xfs/216 |  9 +++++++--
>  tests/xfs/217 | 17 +++++++++++++++--
>  2 files changed, 22 insertions(+), 4 deletions(-)
> 
> diff --git a/tests/xfs/216 b/tests/xfs/216
> index 091c11d08642..8b4610d5a0a6 100755
> --- a/tests/xfs/216
> +++ b/tests/xfs/216
> @@ -21,14 +21,19 @@ _cleanup()
>  }
>  
>  _require_scratch
> -_scratch_mkfs_xfs >/dev/null 2>&1
> +if _scratch_mkfs_supports_concurrency -l >> $seqres.full 2>&1; then
> +	_scratch_mkfs_xfs -l concurrency=0 >/dev/null 2>&1
> +	loop_mkfs_opts="-l concurrency=0"
> +else
> +	_scratch_mkfs_xfs >/dev/null 2>&1
> +	loop_mkfs_opts=
> +fi
>  _scratch_mount
>  
>  _require_loop
>  LOOP_IMG=$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..7c7b33b1ccf7 100755
> --- a/tests/xfs/217
> +++ b/tests/xfs/217
> @@ -20,7 +20,20 @@ _cleanup()
>  }
>  
>  _require_scratch
> -_scratch_mkfs_xfs >/dev/null 2>&1
> +if _scratch_mkfs_supports_concurrency -l >> $seqres.full 2>&1; then
> +	_scratch_mkfs_xfs -l concurrency=0 >/dev/null 2>&1

Why does the scratch fs need a -lconcurrency option?

> +	loop_mkfs_opts="-l concurrency=0"
> +		if _scratch_mkfs_supports_concurrency -d >> $seqres.full 2>&1; then
> +			# We could go just with -l concurency but then on 512CPUs
> +			# it gives log size off by one block so better to set
> +			# -d concurrency to 0.
> +			loop_mkfs_opts="$loop_mkfs_opts -d concurrency=0"

concurrency= was added for -d and -l in the same release (6.7) so you
don't have to test them separately.

--D

> +
> +		fi
> +else
> +	_scratch_mkfs_xfs >/dev/null 2>&1
> +	loop_mkfs_opts=
> +fi
>  _scratch_mount
>  # 16T mkfs requires a bit over 2G free
>  _require_fs_space $SCRATCH_MNT 2202000
> @@ -34,7 +47,7 @@ _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
> -- 
> 2.53.0
> 
>