Re: [RFC PATCH v18 8/8] perf test: Add test for Intel TPEBS counting mode

From: Arnaldo Carvalho de Melo
Date: Mon Aug 12 2024 - 21:24:49 EST


On Sat, Jul 20, 2024 at 02:21:01AM -0400, weilin.wang@xxxxxxxxx wrote:
> From: Weilin Wang <weilin.wang@xxxxxxxxx>
>
> Intel TPEBS sampling mode is supported through perf record. The counting mode
> code uses perf record to capture retire_latency value and use it in metric
> calculation. This test checks the counting mode code on Intel platforms.

root@x1:~# perf test -vvvvv 123
123: test Intel TPEBS counting mode:
--- start ---
test child forked, pid 2600160
Testing without --record-tpebs
Testing with --record-tpebs
---- end(-1) ----
123: test Intel TPEBS counting mode : FAILED!
root@x1:~# grep -m1 "model name" /proc/cpuinfo
model name : 13th Gen Intel(R) Core(TM) i7-1365U
root@x1:~#

What am I missing?

The current codebase is in tmp.perf-tools-next

- Arnaldo

> Signed-off-by: Weilin Wang <weilin.wang@xxxxxxxxx>
> ---
> .../perf/tests/shell/test_stat_intel_tpebs.sh | 19 +++++++++++++++++++
> 1 file changed, 19 insertions(+)
> create mode 100755 tools/perf/tests/shell/test_stat_intel_tpebs.sh
>
> diff --git a/tools/perf/tests/shell/test_stat_intel_tpebs.sh b/tools/perf/tests/shell/test_stat_intel_tpebs.sh
> new file mode 100755
> index 000000000000..c60b29add980
> --- /dev/null
> +++ b/tools/perf/tests/shell/test_stat_intel_tpebs.sh
> @@ -0,0 +1,19 @@
> +#!/bin/bash
> +# test Intel TPEBS counting mode
> +# SPDX-License-Identifier: GPL-2.0
> +
> +set -e
> +grep -q GenuineIntel /proc/cpuinfo || { echo Skipping non-Intel; exit 2; }
> +
> +# Use this event for testing because it should exist in all platforms
> +event=cache-misses:R
> +
> +# Without this cmd option, default value or zero is returned
> +echo "Testing without --record-tpebs"
> +result=$(perf stat -e "$event" true 2>&1)
> +[[ "$result" =~ $event ]] || exit 1
> +
> +# In platforms that do not support TPEBS, it should execute without error.
> +echo "Testing with --record-tpebs"
> +result=$(perf stat -e "$event" --record-tpebs -a sleep 0.01 2>&1)
> +[[ "$result" =~ "perf record" && "$result" =~ $event ]] || exit 1
> --
> 2.43.0
>