linux-kernel - Re: [PATCH v2 3/3] perf test: Add stat uniquifying test

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <CAJpZYjXZGXFC8CwKahCya9sB6J6OOOdsX7=X9mdPfyxQ7DAGGg@mail.gmail.com>
Date: Wed, 23 Apr 2025 15:48:57 -0700
From: Chun-Tse Shao <ctshao@...gle.com>
To: Ian Rogers <irogers@...gle.com>
Cc: linux-kernel@...r.kernel.org, peterz@...radead.org, mingo@...hat.com, 
	acme@...nel.org, namhyung@...nel.org, mark.rutland@....com, 
	alexander.shishkin@...ux.intel.com, jolsa@...nel.org, adrian.hunter@...el.com, 
	kan.liang@...ux.intel.com, ak@...ux.intel.com, howardchu95@...il.com, 
	linux@...blig.org, yeoreum.yun@....com, james.clark@...aro.org, 
	weilin.wang@...el.com, asmadeus@...ewreck.org, 
	linux-perf-users@...r.kernel.org
Subject: Re: [PATCH v2 3/3] perf test: Add stat uniquifying test

On Thu, Apr 3, 2025 at 12:25 PM Ian Rogers <irogers@...gle.com> wrote:
>
> On Thu, Mar 27, 2025 at 4:01 PM Chun-Tse Shao <ctshao@...gle.com> wrote:
> >
> > The `stat+uniquify.sh` test retrieves all uniquified `clockticks` events
> > from `perf list -v clockticks` and check if `perf stat -e clockticks -A`
> > contains all of them.
> >
> > Signed-off-by: Chun-Tse Shao <ctshao@...gle.com>
> > ---
> >  .../tests/shell/stat+event_uniquifying.sh     | 69 +++++++++++++++++++
> >  1 file changed, 69 insertions(+)
> >  create mode 100755 tools/perf/tests/shell/stat+event_uniquifying.sh
> >
> > diff --git a/tools/perf/tests/shell/stat+event_uniquifying.sh b/tools/perf/tests/shell/stat+event_uniquifying.sh
> > new file mode 100755
> > index 000000000000..5ec35c52b7d9
> > --- /dev/null
> > +++ b/tools/perf/tests/shell/stat+event_uniquifying.sh
> > @@ -0,0 +1,69 @@
> > +#!/bin/bash
> > +# perf stat events uniquifying
> > +# SPDX-License-Identifier: GPL-2.0
> > +
> > +set -e
> > +
> > +stat_output=$(mktemp /tmp/__perf_test.stat_output.XXXXX)
> > +perf_tool=perf
> > +err=0
> > +
> > +test_event_uniquifying() {
> > +  # We use `clockticks` to verify the uniquify behavior.
> > +  event="clockticks"
>
> This event is generally only available on Intel, not AMD or ARM, so we
> will need to skip if it isn't present.
>
> > +  # If the `-A` option is added, the event should be uniquified.
> > +  #
> > +  # $perf list -v clockticks
> > +  #
> > +  # List of pre-defined events (to be used in -e or -M):
> > +  #
> > +  #   uncore_imc_0/clockticks/                           [Kernel PMU event]
> > +  #   uncore_imc_1/clockticks/                           [Kernel PMU event]
> > +  #   uncore_imc_2/clockticks/                           [Kernel PMU event]
> > +  #   uncore_imc_3/clockticks/                           [Kernel PMU event]
> > +  #   uncore_imc_4/clockticks/                           [Kernel PMU event]
> > +  #   uncore_imc_5/clockticks/                           [Kernel PMU event]
> > +  #
> > +  #   ...
> > +  #
> > +  # $perf stat -e clockticks -A -- true
> > +  #
> > +  #  Performance counter stats for 'system wide':
> > +  #
> > +  # CPU0            3,773,018      uncore_imc_0/clockticks/
> > +  # CPU0            3,609,025      uncore_imc_1/clockticks/
> > +  # CPU0                    0      uncore_imc_2/clockticks/
> > +  # CPU0            3,230,009      uncore_imc_3/clockticks/
> > +  # CPU0            3,049,897      uncore_imc_4/clockticks/
> > +  # CPU0                    0      uncore_imc_5/clockticks/
> > +  #
> > +  #        0.002029828 seconds time elapsed
> > +
> > +  echo "stat event uniquifying test"
> > +  uniquified_event_array=()
> > +
> > +  # Check how many uniquified events.
> > +  while IFS= read -r line; do
> > +    uniquified_event=$(echo "$line" | awk '{print $1}')
> > +    uniquified_event_array+=("${uniquified_event}")
> > +  done < <(${perf_tool} list -v ${event} | grep "\[Kernel PMU event\]")
>
> Shouldn't the array contain every sysfs event that doesn't have a json
> component? They may or may not be uniquified so I think the array name
> is misleading.
>
> > +  perf_command="${perf_tool} stat -e $event -A -o ${stat_output} -- true"
> > +  $perf_command
> > +
> > +  # Check the output contains all uniquified events.
> > +  for uniquified_event in "${uniquified_event_array[@]}"; do
> > +    if ! cat "${stat_output}" | grep -q "${uniquified_event}"; then
>
> Why not pass the file directly to grep?
> Should some of the events not show in the stat output as you only
> asked for the clockticks event? I'm not sure how this test can pass
> currently.
>
> Thanks,
> Ian
>
Thanks for your comment, Ian.

I tried to run `perf list -v clockticks` and grep for all events which
have `[Kernel PMU event]` tag.
Ideally, that should retrieve all uniquified clockticks events.
Then I ran `perf stat -e clockticks` to check if all events from `perf
list` are showing.

I randomly picked some machines from different arches and it seems
work. Let me know if you have a better idea.

-CT

> > +      echo "Event is not uniquified [Failed]"
> > +      echo "${perf_command}"
> > +      cat "${stat_output}"
> > +      err=1
> > +      break
> > +    fi
> > +  done
> > +}
> > +
> > +test_event_uniquifying
> > +rm -f "${stat_output}"
> > +exit $err
> > --
> > 2.49.0.472.ge94155a9ec-goog
> >