Re: [PATCH 5/5] perf arm-spe: Snapshot mode test

[Leo Yan <leo.yan@linaro.org>]

On Thu, Sep 16, 2021 at 04:46:35PM +0100, German Gomez wrote:
> Shell script test_arm_spe.sh has been added to test the recording of SPE
> tracing events in snapshot mode.
> 
> Reviewed-by: James Clark <james.clark@arm.com>
> Signed-off-by: German Gomez <german.gomez@arm.com>
> ---
>  tools/perf/tests/shell/test_arm_spe.sh | 91 ++++++++++++++++++++++++++
>  1 file changed, 91 insertions(+)
>  create mode 100755 tools/perf/tests/shell/test_arm_spe.sh
> 
> diff --git a/tools/perf/tests/shell/test_arm_spe.sh b/tools/perf/tests/shell/test_arm_spe.sh
> new file mode 100755
> index 000000000000..9ed817e76f95
> --- /dev/null
> +++ b/tools/perf/tests/shell/test_arm_spe.sh
> @@ -0,0 +1,91 @@
> +#!/bin/sh
> +# Check Arm SPE trace data recording and synthesized samples
> +
> +# Uses the 'perf record' to record trace data of Arm SPE events;
> +# then verify if any SPE event samples are generated by SPE with
> +# 'perf script' and 'perf report' commands.
> +
> +# SPDX-License-Identifier: GPL-2.0
> +# German Gomez <german.gomez@arm.com>, 2021
> +
> +skip_if_no_arm_spe_event() {
> +	perf list | egrep -q 'arm_spe_[0-9]+//' && return 0
> +
> +	# arm_spe event doesn't exist
> +	return 2
> +}
> +
> +skip_if_no_arm_spe_event || exit 2
> +
> +perfdata=$(mktemp /tmp/__perf_test.perf.data.XXXXX)
> +glb_err=0
> +
> +cleanup_files()
> +{
> +	rm -f ${perfdata}
> +	trap - exit term int
> +	kill -2 $$ # Forward sigint to parent

I understand you copy this code from Arm cs-etm testing, but I found
the sentence 'kill -2 $$' will cause a failure at my side with the
command:

root@ubuntu:/home/leoy/linux/tools/perf# ./perf test 85 -v
85: Check Arm SPE trace data recording and synthesized samples      :
--- start ---
test child forked, pid 29053
Recording trace with snapshot mode /tmp/__perf_test.perf.data.uughb
Looking at perf.data file for dumping samples:
Looking at perf.data file for reporting samples:
SPE snapshot testing: PASS
test child finished with -1
---- end ----
Check Arm SPE trace data recording and synthesized samples: FAILED!

I changed to use below code and looks it works for me:

        if [[ "$1" == "int" ]]; then
                kill -SIGINT $$
        fi
        if [[ "$1" == "term" ]]; then
                kill -SIGTERM $$
        fi

Thanks,
Leo

> +	exit $glb_err
> +}
> +
> +trap cleanup_files exit term int
> +
> +arm_spe_report() {
> +	if [ $2 != 0 ]; then
> +		echo "$1: FAIL"
> +		glb_err=$2
> +	else
> +		echo "$1: PASS"
> +	fi
> +}
> +
> +perf_script_samples() {
> +	echo "Looking at perf.data file for dumping samples:"
> +
> +	# from arm-spe.c/arm_spe_synth_events()
> +	events="(ld1-miss|ld1-access|llc-miss|lld-access|tlb-miss|tlb-access|branch-miss|remote-access|memory)"
> +
> +	# Below is an example of the samples dumping:
> +	#	dd  3048 [002]          1    l1d-access:      ffffaa64999c __GI___libc_write+0x3c (/lib/aarch64-linux-gnu/libc-2.27.so)
> +	#	dd  3048 [002]          1    tlb-access:      ffffaa64999c __GI___libc_write+0x3c (/lib/aarch64-linux-gnu/libc-2.27.so)
> +	#	dd  3048 [002]          1        memory:      ffffaa64999c __GI___libc_write+0x3c (/lib/aarch64-linux-gnu/libc-2.27.so)
> +	perf script -F,-time -i ${perfdata} 2>&1 | \
> +		egrep " +$1 +[0-9]+ .* +${events}:(.*:)? +" > /dev/null 2>&1
> +}
> +
> +perf_report_samples() {
> +	echo "Looking at perf.data file for reporting samples:"
> +
> +	# Below is an example of the samples reporting:
> +	#   73.04%    73.04%  dd    libc-2.27.so      [.] _dl_addr
> +	#    7.71%     7.71%  dd    libc-2.27.so      [.] getenv
> +	#    2.59%     2.59%  dd    ld-2.27.so        [.] strcmp
> +	perf report --stdio -i ${perfdata} 2>&1 | \
> +		egrep " +[0-9]+\.[0-9]+% +[0-9]+\.[0-9]+% +$1 " > /dev/null 2>&1
> +}
> +
> +arm_spe_snapshot_test() {
> +	echo "Recording trace with snapshot mode $perfdata"
> +	perf record -o ${perfdata} -e arm_spe// -S \
> +		-- dd if=/dev/zero of=/dev/null > /dev/null 2>&1 &
> +	PERFPID=$!
> +
> +	# Wait for perf program
> +	sleep 1
> +
> +	# Send signal to snapshot trace data
> +	kill -USR2 $PERFPID
> +
> +	# Stop perf program
> +	kill $PERFPID
> +	wait $PERFPID
> +
> +	perf_script_samples dd &&
> +	perf_report_samples dd
> +
> +	err=$?
> +	arm_spe_report "SPE snapshot testing" $err
> +}
> +
> +arm_spe_snapshot_test
> +exit $glb_err
> \ No newline at end of file
> -- 
> 2.17.1
>