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

[German Gomez]

Hi Leo,

I'm unable to reproduce. I've tried on top of the most recent perf/core
branch but I still get exit code 0 consistently:

    $ git log
    commit be8ecc57f180415e8a7c1cc5620c5236be2a7e56 (grafted, origin/perf/core)
    Author: Tony Garnock-Jones <tonyg at leastfixedpoint.com>
    Date:   Thu Sep 16 14:09:39 2021 +0200

    $ ./perf test 88 -v
    Couldn't bump rlimit(MEMLOCK), failures may take place when creating BPF maps, etc
    88: Check Arm SPE trace data recording and synthesized samples      :
    --- start ---
    test child forked, pid 18700
    Recording trace with snapshot mode /tmp/__perf_test.perf.data.xgsUt
    Looking at perf.data file for dumping samples:
    Looking at perf.data file for reporting samples:
    SPE snapshot testing: PASS
    test child finished with 0
    ---- end ----
    Check Arm SPE trace data recording and synthesized samples: Ok

On 20/10/2021 14:13, Leo Yan wrote:
> 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 at arm.com>
>> Signed-off-by: German Gomez <german.gomez at 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 at 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 at 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
>>