Re: [PATCH v2] perf test: Add ARM SPE system wide test

From: Leo Yan
Date: Fri Jun 17 2022 - 03:38:52 EST


Hi Namhyung,

On Thu, Jun 16, 2022 at 04:05:46PM -0700, Namhyung Kim wrote:

[...]

> +arm_spe_system_wide_test() {
> + echo "Recording trace with system-wide mode $perfdata"
> + perf record -o ${perfdata} -e arm_spe// -a \
> + -- dd if=/dev/zero of=/dev/null count=100000 > /dev/null 2>&1
> +
> + if [ $? != 0 ]; then
> + arm_spe_report "SPE system-wide testing" 2
> + return
> + fi

I am awared the root permission issue after I saw German's suggestion.

If the snapshot test is passed, no matter the system wide test is passed
or not, we will always return 0 for 'passed' result. But we might miss
to capture the system-wide testing failure.

How about use 'dummy' event to verіfy the root permission?
(actually I referred to intel-pt test):

perf record -o ${tmpfile} -B -N --no-bpf-event -e dummy:u -a true 2>&1 >/dev/null
if [ $? != 0 ]; then
arm_spe_report "SPE system-wide testing" 2
return
fi

perf record -o ${perfdata} -e arm_spe// -a \
-- dd if=/dev/zero of=/dev/null count=100000 > /dev/null 2>&1

Thanks,
Leo

> + perf_script_samples dd &&
> + perf_report_samples dd
> +
> + err=$?
> + arm_spe_report "SPE system-wide testing" $err
> +}
> +
> arm_spe_snapshot_test
> +arm_spe_system_wide_test
> +
> exit $glb_err
> --
> 2.36.1.476.g0c4daa206d-goog
>