On Mon, Jan 17, 2022 at 09:57:05AM +0900, Shin'ichiro Kawasaki wrote: > Test quota disable during btrfs balance and confirm it does not cause > kernel hang. This is a regression test for the problem reported to > linux-btrfs list [1]. The hang was recreated using the test case and > memory backed null_blk device with 5GB size as the scratch device. > > [1] https://lore.kernel.org/linux-btrfs/20220115053012.941761-1-shinichiro.kawasaki@xxxxxxx/ > > Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@xxxxxxx> > --- > tests/btrfs/255 | 42 ++++++++++++++++++++++++++++++++++++++++++ > tests/btrfs/255.out | 2 ++ > 2 files changed, 44 insertions(+) > create mode 100755 tests/btrfs/255 > create mode 100644 tests/btrfs/255.out > > diff --git a/tests/btrfs/255 b/tests/btrfs/255 > new file mode 100755 > index 00000000..16b682ca > --- /dev/null > +++ b/tests/btrfs/255 > @@ -0,0 +1,42 @@ > +#! /bin/bash > +# SPDX-License-Identifier: GPL-2.0 > +# Copyright (c) 2022 Western Digital Corporation or its affiliates. > +# > +# FS QA Test No. btrfs/255 > +# > +# Confirm that disabling quota during balance does not hang > +# > +. ./common/preamble > +_begin_fstest auto qgroup Should have "balance" as well. > + > +# real QA test starts here > +_supported_fs btrfs > +_require_scratch > + > +_scratch_mkfs >> $seqres.full 2>&1 > +_scratch_mount > + > +# Fill 40% of the device or 2GB > +fill_percent=40 > +max_fillsize=$((2*1024*1024*1024)) If the test requires some minimum size, than it should call _require_scratch_size <size in KB> Also please make it a bit more readable by adding a single space before and after each *, i.e. 2 * 1024 * 1024 ... instead of 2*1024*1024. > + > +devsize=$(($(_get_device_size $SCRATCH_DEV) * 512)) > +fillsize=$((devsize * fill_percent / 100)) > +((fillsize > max_fillsize)) && fillsize=$max_fillsize > + > +fs=$((4096*1024)) Same here. > +for ((i=0; i * fs < fillsize; i++)); do And here (i = 0 vs i=0). > + dd if=/dev/zero of=$SCRATCH_MNT/file.$i bs=$fs count=1 \ > + >> $seqres.full 2>&1 > +done > +echo 3 > /proc/sys/vm/drop_caches Why the drop_caches? Please add a comment explaining why it is needed. > + > +# Run btrfs balance and quota enable/disable in parallel > +_run_btrfs_balance_start $SCRATCH_MNT >> $seqres.full & > +$BTRFS_UTIL_PROG quota enable $SCRATCH_MNT > +$BTRFS_UTIL_PROG quota disable $SCRATCH_MNT This seems very timing sensitive. It would be a better stress test if we do the enable/disable in a loop, say 10 or 20 iterations, while another process keeps running balance in parallel and then is killed after the main process finishes the loop of enable/disable quotas. Thanks. > +wait > + > +echo "Silence is golden" > +status=0 > +exit > diff --git a/tests/btrfs/255.out b/tests/btrfs/255.out > new file mode 100644 > index 00000000..7eefb828 > --- /dev/null > +++ b/tests/btrfs/255.out > @@ -0,0 +1,2 @@ > +QA output created by 255 > +Silence is golden > -- > 2.33.1 >
