Re: [PATCH 2/2] xfs/006: new case to test xfs fail_at_unmount error handling

[Eric Sandeen <sandeen@sandeen.net>]

On 5/27/16 10:21 AM, Zorro Lang wrote:
> XFS bring in a new configuration under /sys/fs/xfs/error, named
> fail_at_unmount. It's used to stop unmount retrying forever when
> it hit IO error.
> 
> This case try to unmount an faulty dm device, and to sure unmount
> won't retry forever if fail_at_unmount=1.
> 
> Signed-off-by: Zorro Lang <zlang@redhat.com>
> ---
> 
> Hi,
> 
> Thanks Carlos told this easy way(use dm error) to test this feature, or
> I will try to use dm thinp to reproduce unmount hit an ENOSPC error. That's
> more difficult to do.

right, different errors from dm_thinp.

But I think my simple dm_thinp test and the infrastructure it uses
should make this easy?  It was merged recently.

> I haven't gotten some good ideas to test those /sys/fs/xfs/dm-X/error/
> metadata/... configurations. If someone have good ideas, please let me
> know:)
> 
> Thanks,
> Zorro
> 
>  tests/xfs/006     | 80 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  tests/xfs/006.out |  2 ++
>  tests/xfs/group   |  1 +
>  3 files changed, 83 insertions(+)
>  create mode 100755 tests/xfs/006
>  create mode 100644 tests/xfs/006.out
> 
> diff --git a/tests/xfs/006 b/tests/xfs/006
> new file mode 100755
> index 0000000..dafab50
> --- /dev/null
> +++ b/tests/xfs/006
> @@ -0,0 +1,80 @@
> +#! /bin/bash
> +# FS QA Test 006
> +#
> +# Test xfs' "fail at unmount" error handling configuration. Stop
> +# XFS retrying to writeback forever when unmount.
> +#
> +#-----------------------------------------------------------------------
> +# Copyright (c) 2016 YOUR NAME HERE.  All Rights Reserved.
> +#
> +# This program is free software; you can redistribute it and/or
> +# modify it under the terms of the GNU General Public License as
> +# published by the Free Software Foundation.
> +#
> +# This program is distributed in the hope that it would be useful,
> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> +# GNU General Public License for more details.
> +#
> +# You should have received a copy of the GNU General Public License
> +# along with this program; if not, write the Free Software Foundation,
> +# Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
> +#-----------------------------------------------------------------------
> +#
> +
> +seq=`basename $0`
> +seqres=$RESULT_DIR/$seq
> +echo "QA output created by $seq"
> +
> +here=`pwd`
> +tmp=/tmp/$$
> +status=1	# failure is the default!
> +trap "_cleanup; exit \$status" 0 1 2 3 15
> +
> +_cleanup()
> +{
> +	cd /
> +	rm -f $tmp.*
> +}
> +
> +# get standard environment, filters and checks
> +. ./common/rc
> +. ./common/filter
> +. ./common/dmerror
> +
> +# remove previous $seqres.full before test
> +rm -f $seqres.full
> +
> +# real QA test starts here
> +_supported_fs xfs
> +_supported_os Linux
> +_require_dm_target error
> +_require_scratch
> +_require_scratch_sys_fs error/fail_at_unmount
> +
> +# Format and mount
> +# The device is still a linear device at here
> +_scratch_mkfs > $seqres.full 2>&1

I guess my earlier suggestion was to not mkfs inside the
_require function for sysfs, so maybe move the test here:

_require_fs_sys_fs $SCRATCH_DEV error/fail_at_unmount

> +_dmerror_init
> +_dmerror_mount
> +
> +# Enable fail_at_unmount
> +_enable_xfs_fail_at_unmount $DMERROR_DEV

_set_fs_sys_fs_param $DMERROR_DEV error/fail_at_unmount 1

> +
> +# make some IO at here. If these data still not writeback from
> +# journal to data, it will hit writeback error after load error
> +# tabel in next step.
> +_pwrite_byte 0x61 0 100M $SCRATCH_MNT/file >/dev/null
> +_dmerror_load_error_table
> +
> +# Even above data already all writeback, umount will cause XFS
> +# try to writeback something to root inode. It still can trigger
> +# umount fail.
> +_dmerror_unmount
> +
> +echo "Silence is golden"
> +_dmerror_cleanup
> +
> +# success, all done
> +status=0
> +exit
> diff --git a/tests/xfs/006.out b/tests/xfs/006.out
> new file mode 100644
> index 0000000..675c1b7
> --- /dev/null
> +++ b/tests/xfs/006.out
> @@ -0,0 +1,2 @@
> +QA output created by 006
> +Silence is golden
> diff --git a/tests/xfs/group b/tests/xfs/group
> index f4c6816..39169ea 100644
> --- a/tests/xfs/group
> +++ b/tests/xfs/group
> @@ -4,6 +4,7 @@
>  004 db auto quick
>  005 auto quick
>  007 auto quota quick
> +006 auto quick unmount
>  008 rw ioctl auto quick
>  009 rw ioctl auto prealloc quick
>  010 auto quick repair
>