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

German Gomez
2021-10-20T15:06:58Z

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@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@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
>>