Re: [RFC PATCH v3 2/3] xfs: basic functionality test for shrinking free space in the last AG

[Eryu Guan <guan@eryu.me>]

On Mon, Mar 15, 2021 at 07:19:25PM +0800, Gao Xiang wrote:
> Add basic test to make sure the functionality works as expected.
> 
> Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
> ---
>  tests/xfs/990     | 70 +++++++++++++++++++++++++++++++++++++++++++++++
>  tests/xfs/990.out | 12 ++++++++
>  tests/xfs/group   |  1 +
>  3 files changed, 83 insertions(+)
>  create mode 100755 tests/xfs/990
>  create mode 100644 tests/xfs/990.out
> 
> diff --git a/tests/xfs/990 b/tests/xfs/990
> new file mode 100755
> index 00000000..3c79186e
> --- /dev/null
> +++ b/tests/xfs/990
> @@ -0,0 +1,70 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2021 Red Hat, Inc.  All Rights Reserved.
> +#
> +# FS QA Test 990
> +#
> +# XFS shrinkfs basic functionality test
> +#
> +# This test attempts to shrink with a small size (512K), half AG size and
> +# an out-of-bound size (agsize + 1) to observe if it works as expected.
> +#
> +seq=`basename $0`
> +seqres=$RESULT_DIR/$seq
> +echo "QA output created by $seq"
> +
> +here=`pwd`
> +tmp=/tmp/$$
> +status=1    # failure is the default!
> +trap "rm -f $tmp.*; exit \$status" 0 1 2 3 15
> +
> +# get standard environment, filters and checks
> +. ./common/rc
> +. ./common/filter
> +
> +test_shrink()
> +{
> +	$XFS_GROWFS_PROG -D"$1" $SCRATCH_MNT >> $seqres.full 2>&1
> +	ret=$?

I'm not sure what's the output of xfs_growfs when shrinking filesystem,
if it's easy to do filter, but it'd be good if we could just dump the
output and let .out file match & check the test result.

> +
> +	_scratch_unmount
> +	_repair_scratch_fs >> $seqres.full

_repair_scratch_fs will fix corruption if there's any, and always return 0 if
completes without problems. Is _check_scratch_fs() what you want?

> +	_scratch_mount >> $seqres.full
> +
> +	$XFS_INFO_PROG $SCRATCH_MNT 2>&1 | _filter_mkfs 2>$tmp.growfs >/dev/null
> +	. $tmp.growfs
> +	[ $ret -eq 0 -a $1 -eq $dblocks ]

Just dump the expected size after shrink if possible.

> +}
> +
> +# real QA test starts here
> +_supported_fs xfs

Still missing _require_scratch

> +_require_xfs_shrink
> +
> +rm -f $seqres.full
> +echo "Format and mount"
> +_scratch_mkfs -dsize="$((512 * 1024 * 1024))" -dagcount=3 2>&1 | \
> +	tee -a $seqres.full | _filter_mkfs 2>$tmp.mkfs

Better to explain why mkfs with agcount=3

> +. $tmp.mkfs
> +t_dblocks=$dblocks
> +_scratch_mount >> $seqres.full
> +
> +echo "Shrink fs (small size)"
> +test_shrink $((t_dblocks-512*1024/dbsize)) || \
> +	_fail "Shrink fs (small size) failure"

If it's possible to turn test_shrink to .out file matching way, _fail is
not needed and below.

> +
> +echo "Shrink fs (half AG)"
> +test_shrink $((t_dblocks-agsize/2)) || \
> +	_fail "Shrink fs (half AG) failure"
> +
> +echo "Shrink fs (out-of-bound)"
> +test_shrink $((t_dblocks-agsize-1)) && \
> +	_fail "Shrink fs (out-of-bound) failure"
> +[ $dblocks -ne $((t_dblocks-agsize/2)) ] && \
> +	_fail "dblocks changed after shrinking failure"
> +
> +$XFS_INFO_PROG $SCRATCH_MNT >> $seqres.full
> +echo "*** done"
> +
> +# success, all done
> +status=0
> +exit
> diff --git a/tests/xfs/990.out b/tests/xfs/990.out
> new file mode 100644
> index 00000000..812f89ef
> --- /dev/null
> +++ b/tests/xfs/990.out
> @@ -0,0 +1,12 @@
> +QA output created by 990
> +Format and mount
> +meta-data=DDEV isize=XXX agcount=N, agsize=XXX blks
> +data     = bsize=XXX blocks=XXX, imaxpct=PCT
> +         = sunit=XXX swidth=XXX, unwritten=X
> +naming   =VERN bsize=XXX
> +log      =LDEV bsize=XXX blocks=XXX
> +realtime =RDEV extsz=XXX blocks=XXX, rtextents=XXX
> +Shrink fs (small size)
> +Shrink fs (half AG)
> +Shrink fs (out-of-bound)
> +*** done
> diff --git a/tests/xfs/group b/tests/xfs/group
> index e861cec9..a7981b67 100644
> --- a/tests/xfs/group
> +++ b/tests/xfs/group
> @@ -525,3 +525,4 @@
>  525 auto quick mkfs
>  526 auto quick mkfs
>  527 auto quick quota
> +990 auto quick growfs

Maybe it's time to add a new 'shrinkfs' group?

Thanks,
Eryu