Re: [PATCH v2] btrfs: add test for enable/disable quota and create/destroy qgroup repeatedly

[Filipe Manana <fdmanana@kernel.org>]

On Wed, Mar 02, 2022 at 02:05:48PM +0000, Sidong Yang wrote:
> Test enable/disable quota and create/destroy qgroup repeatedly in
> parallel and confirm it does not cause kernel hang. It only happens
> in kernel staring with kernel 5.17-rc3. This is a regression test
> for the problem reported to linux-btrfs list [1].
> 
> The hang was recreated using the test case and fixed by kernel patch
> titled
> 
>   btrfs: qgroup: fix deadlock between rescan worker and remove qgroup
> 
> [1] https://lore.kernel.org/linux-btrfs/20220228014340.21309-1-realwakka@gmail.com/
> 
> Signed-off-by: Sidong Yang <realwakka@gmail.com>
> ---
> v2 : fix changelog, comments, no wait pids argument
> ---
>  tests/btrfs/262     | 40 ++++++++++++++++++++++++++++++++++++++++
>  tests/btrfs/262.out |  2 ++
>  2 files changed, 42 insertions(+)
>  create mode 100755 tests/btrfs/262
>  create mode 100644 tests/btrfs/262.out
> 
> diff --git a/tests/btrfs/262 b/tests/btrfs/262
> new file mode 100755
> index 00000000..8953a28e
> --- /dev/null
> +++ b/tests/btrfs/262
> @@ -0,0 +1,40 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2022 Sidong Yang.  All Rights Reserved.
> +#
> +# FS QA Test 262
> +#
> +# Test that running qgroup enable, create, destroy, and disable commands in
> +# parallel doesn't result in a deadlock, a crash or any filesystem
> +# inconsistency.
> +#
> +. ./common/preamble
> +_begin_fstest auto quick qgroup
> +
> +# Import common functions.
> +. ./common/filter
> +
> +# real QA test starts here
> +
> +_supported_fs btrfs
> +
> +_require_scratch
> +
> +_scratch_mkfs > /dev/null 2>&1
> +_scratch_mount
> +
> +for ((i = 0; i < 200; i++)); do
> +	$BTRFS_UTIL_PROG quota enable $SCRATCH_MNT 2>> $seqres.full &
> +	$BTRFS_UTIL_PROG qgroup create 1/0 $SCRATCH_MNT 2>> $seqres.full &
> +	$BTRFS_UTIL_PROG qgroup destroy 1/0 $SCRATCH_MNT 2>> $seqres.full &
> +	$BTRFS_UTIL_PROG quota disable $SCRATCH_MNT 2>> $seqres.full &
> +done
> +
> +wait
> +
> +_scratch_unmount

The fstests framework will also do the unmount, so this can be removed.
You don't need to send a new patch version just to remove that, Eryu
can probably amend the patch when he picks it up.

Anyway, it looks good and it works as expected.

Reviewed-by: Filipe Manana <fdmanana@suse.com>

Thanks for making the test case.

> +
> +# success, all done
> +echo "Silence is golden"
> +status=0
> +exit
> diff --git a/tests/btrfs/262.out b/tests/btrfs/262.out
> new file mode 100644
> index 00000000..404badc3
> --- /dev/null
> +++ b/tests/btrfs/262.out
> @@ -0,0 +1,2 @@
> +QA output created by 262
> +Silence is golden
> -- 
> 2.25.1
>