perf test script: Add python script testing support

#!/bin/bash

# perf script python tests

# SPDX-License-Identifier: GPL-2.0

set -e

# set PERF_EXEC_PATH to find scripts in the source directory

perfdir=$(dirname "$0")/../..

if [ -e "$perfdir/scripts/python/Perf-Trace-Util" ]; then

  export PERF_EXEC_PATH=$perfdir

fi

perfdata=$(mktemp /tmp/__perf_test_script_python.perf.data.XXXXX)

generated_script=$(mktemp /tmp/__perf_test_script.XXXXX.py)

cleanup() {

  rm -f "${perfdata}"

  rm -f "${generated_script}"

  trap - EXIT TERM INT

}

trap_cleanup() {

  echo "Unexpected signal in ${FUNCNAME[1]}"

  cleanup

  exit 1

}

trap trap_cleanup TERM INT

trap cleanup EXIT

check_python_support() {

	if perf check feature -q libpython; then

		return 0

	fi

	echo "perf script python test [Skipped: no libpython support]"

	return 2

}

test_script() {

	local event_name=$1

	local expected_output=$2

	local record_opts=$3

	echo "Testing event: $event_name"

	# Try to record. If this fails, it might be permissions or lack of

	# support. Return 2 to indicate "skip this event" rather than "fail

	# test".

	if ! perf record -o "${perfdata}" -e "$event_name" $record_opts -- perf test -w thloop > /dev/null 2>&1; then

		echo "perf script python test [Skipped: failed to record $event_name]"

		return 2

	fi

	echo "Generating python script..."

	if ! perf script -i "${perfdata}" -g "${generated_script}"; then

		echo "perf script python test [Failed: script generation for $event_name]"

		return 1

	fi

	if [ ! -f "${generated_script}" ]; then

		echo "perf script python test [Failed: script not generated for $event_name]"

		return 1

	fi

	# Perf script -g python doesn't generate process_event for generic

	# events so append it manually to test that the callback works.

	if ! grep -q "def process_event" "${generated_script}"; then

		cat <<EOF >> "${generated_script}"

def process_event(param_dict):

	print("param_dict: %s" % param_dict)

EOF

	fi

	echo "Executing python script..."

	output=$(perf script -i "${perfdata}" -s "${generated_script}" 2>&1)

	if echo "$output" | grep -q "$expected_output"; then

		echo "perf script python test [Success: $event_name triggered $expected_output]"

		return 0

	else

		echo "perf script python test [Failed: $event_name did not trigger $expected_output]"

		echo "Output was:"

		echo "$output" | head -n 20

		return 1

	fi

}

check_python_support || exit 2

# Try tracepoint first

test_script "sched:sched_switch" "sched__sched_switch" "-c 1" && res=0 || res=$?

if [ $res -eq 0 ]; then

	exit 0

elif [ $res -eq 1 ]; then

	exit 1

fi

# If tracepoint skipped (res=2), try task-clock

# For generic events like task-clock, the generated script uses process_event()

# which prints the param_dict.

test_script "task-clock" "param_dict" "-c 100" && res=0 || res=$?

if [ $res -eq 0 ]; then

	exit 0

elif [ $res -eq 1 ]; then

	exit 1

fi

# If both skipped

echo "perf script python test [Skipped: Could not record tracepoint or task-clock]"

exit 2