sys_logger_modified.sh

PID_FILE=/data/local/tmp/sys_logger.pid
MYDIR="$(dirname "$(realpath "$0")")"

# also trace the chrome governor
trace_cg=false
trace_threads=true

print_usage()
{
	echo "Usage: $0 [setup (-cg) (-nt) | start | stop | finish]"
}

is_loaded()
{
	if lsmod | grep -q sys_logger; then
		return 0
	fi
	return 1
}

is_enabled()
{
	enabled=`cat /sys/module/sys_logger/parameters/enabled 2>/dev/null`
	if [ $enabled ] ; then
		if [ "$enabled" == 'Y' ]; then
			return 0
		fi
	fi
	return 1
}

setup()
{
	if is_loaded; then
		echo "Error: Already setup!"
	fi

	PARAMS="cpu=2 interval=5"

	`insmod /system/lib/modules/sys_logger.ko $PARAMS`
	ret=$?

	if [ "$ret" != 0 ]; then
		echo "Error: Could not load kernel module"
		exit 1
	fi

	while [ ! -w /sys/module/sys_logger/parameters/enabled ]; do
		# Especially when switching to the interactive governor,
		# the sysfs is sometimes messed up. We have to try reloading
		# the module until it works. (happen also with other modules)
		rmmod sys_logger
		sleep 1

		`insmod $MYDIR/sys_logger.ko $PARAMS`
		ret=$?

		if [ "$ret" != 0 ]; then
			echo "Error: Could not load kernel module"
			exit 1
		fi
		sleep 1
		if [ -w /sys/module/sys_logger/parameters/enabled ]; then
			break;
		fi
	done

	if [ "$trace_cg" = true ]; then
		echo "Preparing to trace sys_logger and chrome governor ..."
		APPEND="-e cpufreq_cg"
	else
		echo "Preparing to trace sys_logger only ..."
		APPEND=""
	fi

	BUFFER_SIZE=20000
	if [ "$trace_threads" = true ]; then
		# in order to detect all chrome threads, we have to trace forks early
		APPEND="$APPEND -e sched:sched_process_fork"
		# We trace rougly 50mb per 30 second (mostly on little CPUs), make the
		# buffers big enough. 8 * 40 MB -> 320 MB
		BUFFER_SIZE=40000
	fi

	# clear all events if enything is pending
	$MYDIR/trace-cmd reset > /dev/null

	# start tracing so we can monitor forks of children (relevant for chrome)
	$MYDIR/trace-cmd start \
		-e sys_logger \
		-e binder_transaction \
		-e cpu_idle \
		-e sched_switch \
		-i \
		-b $BUFFER_SIZE \
		-d -D \
		$APPEND

	ret=$?
	if [ "$ret" != 0 ]; then
		echo "Error: trace-cmd failed"
		rmmod sys_logger
		exit 1
	fi
}

start()
{
	if ! is_loaded; then
		echo "Error: Not setup!"
		exit 1
	elif is_enabled; then
		echo "Error: Already started!"
		exit 1
	fi

	# detect if we are tracing threads via active fork tracing
	tmp=`cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/enable 2>/dev/null`
	if [[ $tmp -eq "1" ]]; then
		# enable all expensive tracing
		echo 1 > /sys/kernel/debug/tracing/events/sched/sched_wakeup/enable
		echo 1 > /sys/kernel/debug/tracing/events/sched/sched_wakeup_new/enable
		echo 1 > /sys/kernel/debug/tracing/events/sched/sched_stat_runtime/enable
	fi

	# start a new measurement run
	echo 1 > /sys/module/sys_logger/parameters/enabled
}

stop()
{
	if ! is_loaded; then
		echo "Error: Not setup!"
		exit 1
	elif ! is_enabled; then
		echo "Error: Not started!"
		exit 1
	fi

	# stop the measurement run
	echo 0 > /sys/module/sys_logger/parameters/enabled

	# detect if we are tracing threads via active fork tracing
	tmp=`cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/enable 2>/dev/null`
	if [[ $tmp -eq "1" ]]; then
		# disable all expensive tracing
		echo 0 > /sys/kernel/debug/tracing/events/sched/sched_wakeup/enable
		echo 0 > /sys/kernel/debug/tracing/events/sched/sched_wakeup_new/enable
		echo 0 > /sys/kernel/debug/tracing/events/sched/sched_stat_runtime/enable
	fi
}

finish()
{
	if ! is_loaded; then
		echo "Error: Not setup!"
		exit 1
	elif is_enabled; then
		stop
	fi

	# stop tracing
	$MYDIR/trace-cmd stop

	# write the trace.dat file
	$MYDIR/trace-cmd extract -o $MYDIR/trace.dat

	# turn of and reset all tracing
	$MYDIR/trace-cmd reset
	
	rm $MYDIR/*.report

	#$MYDIR/trace-cmd report -i $MYDIR/trace.dat > $MYDIR/trace.report

	# unload the module
	rmmod $MYDIR/sys_logger.ko
}

if [ $# -lt 1 ]; then
	print_usage
	exit 1
fi

key="$1"
action=""

while [[ $# -gt 0 ]]
	do
	key="$1"

	case $key in
		setup|start|stop|finish)
			action=$key
			shift # past argument
			;;
		-cg|--chrome-governor)
			if [ "$action" != "setup" ]; then
				print_usage
				exit 1
			fi
			trace_cg=true
			shift # past argument
			;;
		-nt|--no-threads)
			if [ "$action" != "setup" ]; then
				print_usage
				exit 1
			fi
			trace_threads=0
			shift # past argument
			;;
		*)
			print_usage
			exit 1
	esac
done

case "$action" in
	setup)
		setup
		;;
	start)
		start
		;;
	stop)
		stop
		;;
	finish)
		finish
		;;
	*)
		print_usage
		exit 1
esac

exit 0