#!/bin/bash
#
# Common support functions for testing scripts.  If a script-config
# files is available it will be sourced so in-tree kernel modules and
# utilities will be used.  If no script-config can be found then the
# installed kernel modules and utilities will be used.

basedir="$(dirname $0)"

SCRIPT_CONFIG=zfs-script-config.sh
if [ -f "${basedir}/../${SCRIPT_CONFIG}" ]; then
. "${basedir}/../${SCRIPT_CONFIG}"
else
KERNEL_MODULES=(zlib_deflate zlib_inflate)
MODULES=(spl splat zavl znvpair zunicode zcommon zfs)
fi

PROG="<define PROG>"
CLEANUP=
VERBOSE=
VERBOSE_FLAG=
FORCE=
FORCE_FLAG=
DUMP_LOG=
ERROR=
RAID0S=()
RAID10S=()
RAIDZS=()
RAIDZ2S=()
TESTS_RUN=${TESTS_RUN:-'*'}
TESTS_SKIP=${TESTS_SKIP:-}

prefix=@prefix@
exec_prefix=@exec_prefix@
pkgdatadir=@datarootdir@/@PACKAGE@
bindir=@bindir@
sbindir=@sbindir@
udevdir=@udevdir@
udevruledir=@udevruledir@
mounthelperdir=@mounthelperdir@
sysconfdir=@sysconfdir@
localstatedir=@localstatedir@

ETCDIR=${ETCDIR:-/etc}
DEVDIR=${DEVDIR:-/dev/disk/by-vdev}
ZPOOLDIR=${ZPOOLDIR:-${pkgdatadir}/zpool-config}
ZPIOSDIR=${ZPIOSDIR:-${pkgdatadir}/zpios-test}
ZPIOSPROFILEDIR=${ZPIOSPROFILEDIR:-${pkgdatadir}/zpios-profile}
TESTSDIR=${TESTSDIR:-${pkgdatadir}/zfs-tests}
RUNFILEDIR=${RUNFILEDIR:-${pkgdatadir}/runfiles}

ZDB=${ZDB:-${sbindir}/zdb}
ZFS=${ZFS:-${sbindir}/zfs}
ZINJECT=${ZINJECT:-${sbindir}/zinject}
ZHACK=${ZHACK:-${sbindir}/zhack}
ZPOOL=${ZPOOL:-${sbindir}/zpool}
ZTEST=${ZTEST:-${sbindir}/ztest}
ZPIOS=${ZPIOS:-${sbindir}/zpios}

COMMON_SH=${COMMON_SH:-${pkgdatadir}/common.sh}
ZFS_SH=${ZFS_SH:-${pkgdatadir}/zfs.sh}
ZPOOL_CREATE_SH=${ZPOOL_CREATE_SH:-${pkgdatadir}/zpool-create.sh}
ZPIOS_SH=${ZPIOS_SH:-${pkgdatadir}/zpios.sh}
ZPIOS_SURVEY_SH=${ZPIOS_SURVEY_SH:-${pkgdatadir}/zpios-survey.sh}
TEST_RUNNER=${TEST_RUNNER:-${pkgdatadir}/test-runner/bin/test-runner.py}
STF_TOOLS=${STF_TOOLS:-${pkgdatadir}/test-runner}
STF_SUITE=${STF_SUITE:-${pkgdatadir}/zfs-tests}

LDMOD=${LDMOD:-/sbin/modprobe}
LSMOD=${LSMOD:-/sbin/lsmod}
RMMOD=${RMMOD:-/sbin/rmmod}
INFOMOD=${INFOMOD:-/sbin/modinfo}
LOSETUP=${LOSETUP:-/sbin/losetup}
MDADM=${MDADM:-/sbin/mdadm}
DMSETUP=${DMSETUP:-/sbin/dmsetup}
PARTED=${PARTED:-/sbin/parted}
BLOCKDEV=${BLOCKDEV:-/sbin/blockdev}
LSSCSI=${LSSCSI:-/usr/bin/lsscsi}
SCSIRESCAN=${SCSIRESCAN:-/usr/bin/scsi-rescan}
SYSCTL=${SYSCTL:-/sbin/sysctl}
UDEVADM=${UDEVADM:-/sbin/udevadm}
AWK=${AWK:-/usr/bin/awk}
GDB=${GDB:-/usr/bin/gdb}

ZED_PIDFILE=${ZED_PIDFILE:-${localstatedir}/run/zed.pid}

COLOR_BLACK="\033[0;30m"
COLOR_DK_GRAY="\033[1;30m"
COLOR_BLUE="\033[0;34m"
COLOR_LT_BLUE="\033[1;34m" 
COLOR_GREEN="\033[0;32m"
COLOR_LT_GREEN="\033[1;32m"
COLOR_CYAN="\033[0;36m"
COLOR_LT_CYAN="\033[1;36m"
COLOR_RED="\033[0;31m"
COLOR_LT_RED="\033[1;31m"
COLOR_PURPLE="\033[0;35m"
COLOR_LT_PURPLE="\033[1;35m"
COLOR_BROWN="\033[0;33m"
COLOR_YELLOW="\033[1;33m"
COLOR_LT_GRAY="\033[0;37m"
COLOR_WHITE="\033[1;37m"
COLOR_RESET="\033[0m"

die() {
	echo -e "${PROG}: $1" >&2
	exit 1
}

msg() {
	if [ ${VERBOSE} ]; then
		echo "$@"
	fi
}

pass() {
	echo -e "${COLOR_GREEN}Pass${COLOR_RESET}"
}

fail() {
	echo -e "${COLOR_RED}Fail${COLOR_RESET} ($1)"
	exit $1
}

skip() {
	echo -e "${COLOR_BROWN}Skip${COLOR_RESET}"
}

populate() {
	local ROOT=$1
	local MAX_DIR_SIZE=$2
	local MAX_FILE_SIZE=$3

	mkdir -p $ROOT/{a,b,c,d,e,f,g}/{h,i}
	DIRS=`find $ROOT`

	for DIR in $DIRS; do
		COUNT=$(($RANDOM % $MAX_DIR_SIZE))

		for i in `seq $COUNT`; do
			FILE=`mktemp -p ${DIR}`
			SIZE=$(($RANDOM % $MAX_FILE_SIZE))
			dd if=/dev/urandom of=$FILE bs=1k count=$SIZE &>/dev/null
		done
	done

	return 0
}

init() {
	# Disable the udev rule 90-zfs.rules to prevent the zfs module
	# stack from being loaded due to the detection of a zfs device.
	# This is important because the test scripts require full control
	# over when and how the modules are loaded/unloaded.  A trap is
	# set to ensure the udev rule is correctly replaced on exit.
	local RULE=${udevruledir}/90-zfs.rules
	if test -e  ${RULE}; then
		trap "mv ${RULE}.disabled ${RULE}" INT TERM EXIT
		mv ${RULE} ${RULE}.disabled
	fi

	# Create a random directory tree of files and sub-directories to
	# to act as a copy source for the various regression tests.
	SRC_DIR=`mktemp -d -p /var/tmp/ zfs.src.XXXXXXXX`
	trap "rm -Rf $SRC_DIR" INT TERM EXIT
	populate $SRC_DIR 10 100
}

spl_dump_log() {
	${SYSCTL} -w kernel.spl.debug.dump=1 &>/dev/null
	local NAME=`dmesg | tail -n 1 | cut -f5 -d' '`
	${SPLBUILD}/cmd/spl ${NAME} >${NAME}.log
	echo
	echo "Dumped debug log: ${NAME}.log"
	tail -n1 ${NAME}.log
	echo
	return 0
}

check_modules() {
	local LOADED_MODULES=()
	local MISSING_MODULES=()

	for MOD in ${MODULES[*]}; do
		local NAME=`basename $MOD .ko`

		if ${LSMOD} | egrep -q "^${NAME}"; then
			LOADED_MODULES=(${NAME} ${LOADED_MODULES[*]})
		fi

		if [ ${INFOMOD} ${MOD} 2>/dev/null ]; then
			MISSING_MODULES=("\t${MOD}\n" ${MISSING_MODULES[*]})
		fi
	done

	if [ ${#LOADED_MODULES[*]} -gt 0 ]; then
		ERROR="Unload these modules with '${PROG} -u':\n"
		ERROR="${ERROR}${LOADED_MODULES[*]}"
		return 1
	fi

	if [ ${#MISSING_MODULES[*]} -gt 0 ]; then
		ERROR="The following modules can not be found,"
		ERROR="${ERROR} ensure your source trees are built:\n"
		ERROR="${ERROR}${MISSING_MODULES[*]}"
		return 1
	fi

	return 0
}

load_module() {
	local NAME=`basename $1 .ko`

	if [ ${VERBOSE} ]; then
		echo "Loading ${NAME} ($@)"
	fi

	${LDMOD} $* &>/dev/null
	if [ $? -ne 0 ]; then
		echo "Failed to load ${NAME} ($@)"
		return 1
	fi

	return 0
}

load_modules() {
	mkdir -p /etc/zfs

	for MOD in ${KERNEL_MODULES[*]}; do
		load_module ${MOD} >/dev/null
	done

	for MOD in ${MODULES[*]}; do
		local NAME=`basename ${MOD} .ko`
		local VALUE=

		for OPT in "$@"; do
			OPT_NAME=`echo ${OPT} | cut -f1 -d'='`

			if [ ${NAME} = "${OPT_NAME}" ]; then
				VALUE=`echo ${OPT} | cut -f2- -d'='`
			fi
		done

		load_module ${MOD} ${VALUE} || return 1
	done

	if [ ${VERBOSE} ]; then
		echo "Successfully loaded ZFS module stack"
	fi

	return 0
}

unload_module() {
	local NAME=`basename $1 .ko`

	if [ ${VERBOSE} ]; then
		echo "Unloading ${NAME} ($@)"
	fi

	${RMMOD} ${NAME} || ERROR="Failed to unload ${NAME}" return 1

	return 0
}

unload_modules() {
	local MODULES_REVERSE=( $(echo ${MODULES[@]} |
		${AWK} '{for (i=NF;i>=1;i--) printf $i" "} END{print ""}') )

	for MOD in ${MODULES_REVERSE[*]}; do
		local NAME=`basename ${MOD} .ko`
		local USE_COUNT=`${LSMOD} |
				egrep "^${NAME} "| ${AWK} '{print $3}'`

		if [ "${USE_COUNT}" = 0 ] ; then

			if [ "${DUMP_LOG}" -a ${NAME} = "spl" ]; then
				spl_dump_log
			fi

			unload_module ${MOD} || return 1
		fi
	done

	if [ ${VERBOSE} ]; then
		echo "Successfully unloaded ZFS module stack"
	fi

	return 0
}

#
# Check that the mdadm utilities are installed.
#
check_loop_utils() {
        test -f ${LOSETUP} || die "${LOSETUP} utility must be installed"
}


#
# Find and return an unused loop device.  A new /dev/loopN node will be
# created if required.  The kernel loop driver will automatically register
# the minor as long as it's less than /sys/module/loop/parameters/max_loop.
#
unused_loop_device() {
	local DEVICE=$(${LOSETUP} -f)
	local MAX_LOOP_PATH="/sys/module/loop/parameters/max_loop"
	local MAX_LOOP;

	# An existing /dev/loopN device was available.
	if [ -n "${DEVICE}" ]; then
		echo "${DEVICE}"
		return 0
	fi

	# Create a new /dev/loopN provided we are not at MAX_LOOP.
	if [ -f "${MAX_LOOP_PATH}" ]; then
		MAX_LOOP=`cat /sys/module/loop/parameters/max_loop`
		if [ ${MAX_LOOP} -eq 0 ]; then
			MAX_LOOP=255
		fi

		for (( i=0; i<=${MAX_LOOP}; i++ )); do
			DEVICE="/dev/loop$i"

			if [ -b "${DEVICE}" ]; then
				continue
			else
				mknod -m660 "${DEVICE}" b 7 $i
				chown root.disk "${DEVICE}"
				chmod 666 "${DEVICE}"

				echo "${DEVICE}"
				return 0
			fi
		done
	fi

	die "Error: Unable to create new loopback device"
}

#
# This can be slightly dangerous because the loop devices we are
# cleaning up may not be ours.  However, if the devices are currently
# in use we will not be able to remove them, and we only remove
# devices which include 'zpool' or 'deleted' in the name.  So any
# damage we might do should be limited to other zfs related testing.
#
cleanup_loop_devices() {
	local TMP_FILE=`mktemp`

	${LOSETUP} -a | tr -d '()' >${TMP_FILE}
	${AWK} -F":" -v losetup="$LOSETUP" \
	    '/zpool/ || /deleted/ { system("losetup -d "$1) }' ${TMP_FILE}
	${AWK} -F" " '/zpool/ || /deleted/ { system("rm -f "$3) }' ${TMP_FILE}

	rm -f ${TMP_FILE}
}

#
# Destroy the passed loopback devices, this is used when you know
# the names of the loopback devices.
#
destroy_loop_devices() {
	local LODEVICES="$1"

	msg "Destroying ${LODEVICES}"
	${LOSETUP} -d ${LODEVICES} || \
		die "Error $? destroying ${FILE} -> ${DEVICE} loopback"

	rm -f ${FILES}
	return 0
}

#
# Create a device label taking care to briefly wait if udev needs to settle.
#
label() {
	local DEVICE=$1
	local LABEL=$2

	wait_udev ${DEVICE} 30 || return 1
	${PARTED} ${DEVICE} --script -- mklabel ${LABEL} || return 2

	return 0
}

#
# Create a primary partition on a block device.
#
partition() {
	local DEVICE=$1
	local TYPE=$2
	local START=$3
	local END=$4

	${PARTED} --align optimal ${DEVICE} --script -- \
	    mkpart ${TYPE} ${START} ${END} || return 1
	udev_trigger

	return 0
}

#
# Create a filesystem on the block device
#
format() {
	local DEVICE=$1
	local FSTYPE=$2

	# Force 4K blocksize, else mkfs.ext2 tries to use 8K, which
	# won't mount
	/sbin/mkfs.${FSTYPE} -b 4096 -F -q ${DEVICE} >/dev/null || return 1

	return 0
}

#
# Check that the mdadm utilities are installed.
#
check_md_utils() {
        test -f ${MDADM} || die "${MDADM} utility must be installed"
	test -f ${PARTED} || die "${PARTED} utility must be installed"
}

check_md_partitionable() {
	local LOFILE=`mktemp -p /tmp zpool-lo.XXXXXXXX`
	local LODEVICE=`unused_loop_device`
	local MDDEVICE=`unused_md_device`
	local RESULT=1

	check_md_utils

	rm -f ${LOFILE}
	dd if=/dev/zero of=${LOFILE} bs=1M count=0 seek=16 \
		&>/dev/null || return ${RESULT}

	msg "Creating ${LODEVICE} using ${LOFILE}"
	${LOSETUP} ${LODEVICE} ${LOFILE}
	if [ $? -ne 0 ]; then
		rm -f ${LOFILE}
		return ${RESULT}
	fi

	msg "Creating ${MDDEVICE} using ${LODEVICE}"
	${MDADM} --build ${MDDEVICE} --level=faulty \
		--raid-devices=1 ${LODEVICE} &>/dev/null
	if [ $? -ne 0 ]; then
		destroy_loop_devices ${LODEVICE}
		rm -f ${LOFILE}
		return ${RESULT}
	fi
	wait_udev ${MDDEVICE} 30

	${BLOCKDEV} --rereadpt ${MDDEVICE} 2>/dev/null
	RESULT=$?

	destroy_md_devices ${MDDEVICE}
	destroy_loop_devices ${LODEVICE}
	rm -f ${LOFILE}

	return ${RESULT}
}

#
# Find and return an unused md device.
#
unused_md_device() {
	for (( i=0; i<32; i++ )); do
		MDDEVICE=md${i}

		# Skip active devicesudo in /proc/mdstat.
		grep -q "${MDDEVICE} " /proc/mdstat && continue

		# Device doesn't exist, use it.
		if [ ! -e $/dev/{MDDEVICE} ]; then
			echo /dev/${MDDEVICE}
			return
		fi

		# Device exists but may not be in use.
		if [ -b /dev/${MDDEVICE} ]; then
			${MDADM} --detail /dev/${MDDEVICE} &>/dev/null
			if [ $? -eq 1 ]; then
				echo /dev/${MDDEVICE}
				return
			fi
		fi
        done

        die "Error: Unable to find unused md device"
}

#
# This can be slightly dangerous because it is possible the md devices
# we are cleaning up may not be ours.  However, if the devices are
# currently in use we will not be able to remove them, and even if
# we remove devices which were not out we do not zero the super block
# so you should be able to reconstruct them.
#
cleanup_md_devices() {
	destroy_md_devices "`ls /dev/md* 2>/dev/null | grep -v p`"
	udev_trigger
}

#
# Destroy the passed md devices, this is used when you know
# the names of the md devices.
#
destroy_md_devices() {
	local MDDEVICES="$1"

	msg "Destroying ${MDDEVICES}"
	for MDDEVICE in ${MDDEVICES}; do
		${MDADM} --stop ${MDDEVICE} &>/dev/null
		${MDADM} --remove ${MDDEVICE} &>/dev/null
		${MDADM} --detail ${MDDEVICE} &>/dev/null
	done

	return 0
}

#
# Check that the scsi utilities are installed.
#
check_sd_utils() {
	${INFOMOD} scsi_debug &>/dev/null || die "scsi_debug module required"
	test -f ${LSSCSI} || die "${LSSCSI} utility must be installed"
}

#
# Rescan the scsi bus for scsi_debug devices.  It is preferable to use the
# scsi-rescan tool if it is installed, but if it's not we can fall back to
# removing and readding the device manually.  This rescan will only effect
# the first scsi_debug device if scsi-rescan is missing.
#
scsi_rescan() {
	local AWK_SCRIPT="/scsi_debug/ { print \$1; exit }"

	if [ -f ${SCSIRESCAN} ]; then
		${SCSIRESCAN} --forcerescan --remove &>/dev/null
	else
		local SCSIID=`${LSSCSI} | ${AWK} "${AWK_SCRIPT}" | tr -d '[]'`
		local SCSIHOST=`echo ${SCSIID} | cut -f1 -d':'`
		echo 1 >"/sys/class/scsi_device/${SCSIID}/device/delete"
		udev_trigger
		echo "- - -" >/sys/class/scsi_host/host${SCSIHOST}/scan
		udev_trigger
	fi
}

#
# Trigger udev and wait for it to settle.
#
udev_trigger() {
	if [ -f ${UDEVADM} ]; then
		${UDEVADM} trigger --action=change --subsystem-match=block
		${UDEVADM} settle
	else
		/sbin/udevtrigger
		/sbin/udevsettle
	fi
}

#
# The following udev helper functions assume that the provided
# udev rules file will create a /dev/disk/by-vdev/<CHANNEL><RANK>
# disk mapping.  In this mapping each CHANNEL is represented by
# the letters a-z, and the RANK is represented by the numbers
# 1-n.  A CHANNEL should identify a group of RANKS which are all
# attached to a single controller, each RANK represents a disk.
# This provides a simply mechanism to locate a specific drive
# given a known hardware configuration.
#
udev_setup() {
	local SRC_PATH=$1

	# When running in tree manually contruct symlinks in tree to
	# the proper devices.  Symlinks are installed for all entires
	# in the config file regardless of if that device actually
	# exists.  When installed as a package udev can be relied on for
	# this and it will only create links for devices which exist.
	if [ ${INTREE} ]; then
		PWD=`pwd`
		mkdir -p ${DEVDIR}/
		cd ${DEVDIR}/
		${AWK} '!/^#/ && /./ { system( \
			"ln -f -s /dev/disk/by-path/"$2" "$1";" \
			"ln -f -s /dev/disk/by-path/"$2"-part1 "$1"p1;" \
			"ln -f -s /dev/disk/by-path/"$2"-part9 "$1"p9;" \
			) }' $SRC_PATH
		cd ${PWD}
	else
		DST_FILE=`basename ${SRC_PATH} | cut -f1-2 -d'.'`
		DST_PATH=/etc/zfs/${DST_FILE}

		if [ -e ${DST_PATH} ]; then
			die "Error: Config ${DST_PATH} already exists"
		fi

		cp ${SRC_PATH} ${DST_PATH}
		udev_trigger
	fi

	return 0
}

udev_cleanup() {
	local SRC_PATH=$1

	if [ ${INTREE} ]; then
		PWD=`pwd`
		cd ${DEVDIR}/
		${AWK} '!/^#/ && /./ { system( \
			"rm -f "$1" "$1"p1 "$1"p9") }' $SRC_PATH
		cd ${PWD}
	fi

	return 0
}

udev_cr2d() {
	local CHANNEL=`echo "obase=16; $1+96" | bc`
	local RANK=$2

	printf "\x${CHANNEL}${RANK}"
}

udev_raid0_setup() {
	local RANKS=$1
	local CHANNELS=$2
	local IDX=0

	RAID0S=()
	for RANK in `seq 1 ${RANKS}`; do
		for CHANNEL in `seq 1 ${CHANNELS}`; do
			DISK=`udev_cr2d ${CHANNEL} ${RANK}`
			RAID0S[${IDX}]="${DEVDIR}/${DISK}"
			let IDX=IDX+1
		done
	done

	return 0
}

udev_raid10_setup() {
	local RANKS=$1
	local CHANNELS=$2
	local IDX=0

	RAID10S=()
	for RANK in `seq 1 ${RANKS}`; do
		for CHANNEL1 in `seq 1 2 ${CHANNELS}`; do
			let CHANNEL2=CHANNEL1+1
			DISK1=`udev_cr2d ${CHANNEL1} ${RANK}`
			DISK2=`udev_cr2d ${CHANNEL2} ${RANK}`
			GROUP="${DEVDIR}/${DISK1} ${DEVDIR}/${DISK2}"
			RAID10S[${IDX}]="mirror ${GROUP}"
			let IDX=IDX+1
		done
	done

	return 0
}

udev_raidz_setup() {
	local RANKS=$1
	local CHANNELS=$2

	RAIDZS=()
	for RANK in `seq 1 ${RANKS}`; do
		RAIDZ=("raidz")

		for CHANNEL in `seq 1 ${CHANNELS}`; do
			DISK=`udev_cr2d ${CHANNEL} ${RANK}`
			RAIDZ[${CHANNEL}]="${DEVDIR}/${DISK}"
		done

		RAIDZS[${RANK}]="${RAIDZ[*]}"
	done

	return 0
}

udev_raidz2_setup() {
	local RANKS=$1
	local CHANNELS=$2

	RAIDZ2S=()
	for RANK in `seq 1 ${RANKS}`; do
		RAIDZ2=("raidz2")

		for CHANNEL in `seq 1 ${CHANNELS}`; do
			DISK=`udev_cr2d ${CHANNEL} ${RANK}`
			RAIDZ2[${CHANNEL}]="${DEVDIR}/${DISK}"
		done

		RAIDZ2S[${RANK}]="${RAIDZ2[*]}"
	done

	return 0
}

run_one_test() {
	local TEST_NUM=$1
	local TEST_NAME=$2

	printf "%-4d %-34s " ${TEST_NUM} "${TEST_NAME}"
	test_${TEST_NUM}
}

skip_one_test() {
	local TEST_NUM=$1
	local TEST_NAME=$2

	printf "%-4d %-34s " ${TEST_NUM} "${TEST_NAME}"
	skip
}

run_test() {
	local TEST_NUM=$1
	local TEST_NAME=$2

	for i in ${TESTS_SKIP[@]}; do
		if [[ $i == ${TEST_NUM} ]] ; then
			skip_one_test ${TEST_NUM} "${TEST_NAME}"
			return 0
		fi
	done

	if [ "${TESTS_RUN[0]}" = "*" ]; then
		run_one_test ${TEST_NUM} "${TEST_NAME}"
	else
		for i in ${TESTS_RUN[@]}; do
			if [[ $i == ${TEST_NUM} ]] ; then
				run_one_test ${TEST_NUM} "${TEST_NAME}"
				return 0
			fi
		done

		skip_one_test ${TEST_NUM} "${TEST_NAME}"
	fi
}

wait_udev() {
	local DEVICE=$1
	local DELAY=$2
	local COUNT=0

	udev_trigger
	while [ ! -e ${DEVICE} ]; do
		if [ ${COUNT} -gt ${DELAY} ]; then
			return 1
		fi

		let COUNT=${COUNT}+1
	        sleep 1
	done

	return 0
}

stack_clear() {
	local STACK_MAX_SIZE=/sys/kernel/debug/tracing/stack_max_size
	local STACK_TRACER_ENABLED=/proc/sys/kernel/stack_tracer_enabled

	if [ -e $STACK_MAX_SIZE ]; then
		echo 1 >$STACK_TRACER_ENABLED
		echo 0 >$STACK_MAX_SIZE
	fi
}

stack_check() {
	local STACK_MAX_SIZE=/sys/kernel/debug/tracing/stack_max_size
	local STACK_TRACE=/sys/kernel/debug/tracing/stack_trace
	local STACK_LIMIT=7000

	if [ -e $STACK_MAX_SIZE ]; then
		STACK_SIZE=`cat $STACK_MAX_SIZE`

		if [ $STACK_SIZE -ge $STACK_LIMIT ]; then
			echo
			echo "Warning: max stack size $STACK_SIZE bytes"
			cat $STACK_TRACE
		fi
	fi
}

kill_zed() {
        if [ -f $ZED_PIDFILE ]; then
		kill $(cat $ZED_PIDFILE)
        fi
}