linux-kernel - Re: [PATCH v5 00/16] Intel TPEBS min/max/mean/last support

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] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAP-5=fVo_yGgEwndavWaNAQRg=1MR121PQ-KwOW0HsUWGBLLnA@mail.gmail.com>
Date: Mon, 21 Apr 2025 11:13:49 -0700
From: Ian Rogers <irogers@...gle.com>
To: "Liang, Kan" <kan.liang@...ux.intel.com>
Cc: Peter Zijlstra <peterz@...radead.org>, Ingo Molnar <mingo@...hat.com>, 
	Arnaldo Carvalho de Melo <acme@...nel.org>, Namhyung Kim <namhyung@...nel.org>, 
	Mark Rutland <mark.rutland@....com>, 
	Alexander Shishkin <alexander.shishkin@...ux.intel.com>, Jiri Olsa <jolsa@...nel.org>, 
	Adrian Hunter <adrian.hunter@...el.com>, Andreas Färber <afaerber@...e.de>, 
	Manivannan Sadhasivam <manivannan.sadhasivam@...aro.org>, 
	Maxime Coquelin <mcoquelin.stm32@...il.com>, Alexandre Torgue <alexandre.torgue@...s.st.com>, 
	Caleb Biggers <caleb.biggers@...el.com>, Weilin Wang <weilin.wang@...el.com>, 
	linux-kernel@...r.kernel.org, linux-perf-users@...r.kernel.org, 
	Perry Taylor <perry.taylor@...el.com>, Thomas Falcon <thomas.falcon@...el.com>
Subject: Re: [PATCH v5 00/16] Intel TPEBS min/max/mean/last support

On Mon, Apr 14, 2025 at 12:08 PM Liang, Kan <kan.liang@...ux.intel.com> wrote:
>
>
>
> On 2025-04-14 1:41 p.m., Ian Rogers wrote:
> > The patches add support to computing the min, max, mean or last
> > retirement latency and then using that value as the basis for metrics.
> > When values aren't available, support is added to use the retirement
> > latency as recorded for an event in the perf json.
> >
> > Support is added for reading the retirement latency from the forked
> > perf command more than once. To avoid killing the process commands are
> > sent through the control fd. Some name handling is changed to make it
> > more robust.
> >
> > Rather than retirement latency events having issues with perf record,
> > make it so that the retirement latency modifier enables sample
> > weights.
> >
> > Note: the retirement latency JSON updates are part of:
> > https://lore.kernel.org/lkml/20250328175006.43110-1-irogers@google.com/
> >
> > v5: Add Namhyung and Weilin's tags. Fix missing error path mutex
> >     unlock spotted by Namhyung.
> >
> > v4: Don't use json min/max in retirement latency stats as they will
> >     never update afterwards. Warn once if json data is used when TPEBS
> >     recording was requested.
> >
> > v3: Two fixes from Kan Liang. Ensure min/max statistics don't vary
> >     when real samples are encountered.
> >
> > v2: Addition of header cleanup patch originally posted:
> >     https://lore.kernel.org/lkml/20241210191823.612631-1-irogers@google.com/
> >     as there are no arch specific reasons not to build this code.
> >     Fix bug in "perf pmu-events: Add retirement latency to JSON events
> >     inside of perf" where "t->stats.n != 0" should have been
> >     "t->stats.n == 0".
> >     Add patch so that perf record of a retirement latency event
> >     doesn't crash but instead enables sample weights for the event.
> >
> > Ian Rogers (16):
> >   perf intel-tpebs: Cleanup header
> >   perf intel-tpebs: Simplify tpebs_cmd
> >   perf intel-tpebs: Rename tpebs_start to evsel__tpebs_open
> >   perf intel-tpebs: Separate evsel__tpebs_prepare out of
> >     evsel__tpebs_open
> >   perf intel-tpebs: Move cpumap_buf out of evsel__tpebs_open
> >   perf intel-tpebs: Reduce scope of tpebs_events_size
> >   perf intel-tpebs: Inline get_perf_record_args
> >   perf intel-tpebs: Ensure events are opened, factor out finding
> >   perf intel-tpebs: Refactor tpebs_results list
> >   perf intel-tpebs: Add support for updating counts in evsel__tpebs_read
> >   perf intel-tpebs: Add mutex for tpebs_results
> >   perf intel-tpebs: Don't close record on read
> >   perf intel-tpebs: Use stats for retirement latency statistics
> >   perf stat: Add mean, min, max and last --tpebs-mode options
> >   perf pmu-events: Add retirement latency to JSON events inside of perf
> >   perf record: Retirement latency cleanup in evsel__config
> >
>
> Reviewed-by: Kan Liang <kan.liang@...ux.intel.com>

Ping.

It would be great if we could land:
https://lore.kernel.org/lkml/CAP-5=fWxuKHLZJjd2NVWjA7ktCX6X3yQBsH2kh+eTTaNcSqbTg@mail.gmail.com/T/#m1bba00c3a699397b54e1a77da9b9ff392b435e4d
and then land this series.

Thanks,
Ian

> Thanks,
> Kan
>
>
> >  tools/perf/Documentation/perf-stat.txt   |   7 +
> >  tools/perf/builtin-stat.c                |  29 +-
> >  tools/perf/pmu-events/empty-pmu-events.c | 216 +++----
> >  tools/perf/pmu-events/jevents.py         |   6 +
> >  tools/perf/pmu-events/pmu-events.h       |   3 +
> >  tools/perf/util/Build                    |   2 +-
> >  tools/perf/util/evlist.c                 |   1 -
> >  tools/perf/util/evsel.c                  |  22 +-
> >  tools/perf/util/evsel.h                  |   6 +
> >  tools/perf/util/intel-tpebs.c            | 682 ++++++++++++++---------
> >  tools/perf/util/intel-tpebs.h            |  40 +-
> >  tools/perf/util/parse-events.c           |   4 +
> >  tools/perf/util/pmu.c                    |  52 +-
> >  tools/perf/util/pmu.h                    |   3 +
> >  14 files changed, 666 insertions(+), 407 deletions(-)
> >
>