#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2020 SUSE Linux Products GmbH. All Rights Reserved.
#
# FS QA Test 213
#
# Test if canceling a running balance can lead to dead looping balance
#
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 /
	kill $write_pid &> /dev/null
	rm -f $tmp.*
}

# get standard environment, filters and checks
. ./common/rc
. ./common/filter

# remove previous $seqres.full before test
rm -f $seqres.full

# Modify as appropriate.
_supported_fs btrfs
_require_scratch
_require_xfs_io_command pwrite -D

_scratch_mkfs >> $seqres.full
_scratch_mount

runtime=4

# Create enough IO so that we need around $runtime seconds to relocate it.
#
# Here we don't want any wrapper, as we want full control of the process.
$XFS_IO_PROG -f -c "pwrite -D -b 1M 0 1024T" "$SCRATCH_MNT/file" &> /dev/null &
write_pid=$!
sleep $runtime
kill $write_pid
wait $write_pid

# Now balance should take at least $runtime seconds, we can cancel it at
# $runtime/2 to ensure a success cancel.
_run_btrfs_balance_start -d --bg "$SCRATCH_MNT"
sleep $(($runtime / 2))
$BTRFS_UTIL_PROG balance cancel "$SCRATCH_MNT"

# Now check if we can finish relocating metadata, which should finish very
# quickly.
$BTRFS_UTIL_PROG balance start -m "$SCRATCH_MNT" >> $seqres.full

echo "Silence is golden"

# success, all done
status=0
exit