[PATCH v3 0/4] Add support for a DRM tool like PMU

[Ian Rogers]

On Wed, Apr 30, 2025 at 4:36 PM Arnaldo Carvalho de Melo
<acme at kernel.org> wrote:
>
> On Wed, Apr 30, 2025 at 08:21:59AM -0700, Ian Rogers wrote:
> > On Thu, Apr 3, 2025 at 1:24 PM Ian Rogers <irogers at google.com> wrote:
> > >
> > > DRM clients expose information through usage stats as documented in
> > > Documentation/gpu/drm-usage-stats.rst (available online at
> > > https://docs.kernel.org/gpu/drm-usage-stats.html). Add a tool like
> > > PMU, similar to the hwmon PMU, that exposes DRM information.
>
> Looks useful, I'll try to review and test tomorrow, but most probably
> Friday, as tomorrow is labour day in this part of the world.

Ping. Thanks,
Ian

> - Arnaldo
>
> > I'm reminded by Brendan Gregg's new blog:
> > https://www.brendangregg.com/blog/2025-05-01/doom-gpu-flame-graphs.html
> > that this is still outstanding. The patches also reduce some directory
> > scanning for the hwmon "PMU", they are in Google's tree:
> > https://github.com/googleprodkernel/linux-perf/blob/google_tools_master/tools/perf/util/drm_pmu.c
> >
> > Thanks,
> > Ian
> >
> > > v3: Minor tweak to the test so the skip (exit 2) doesn't trigger the
> > >     trap cleanup.
> > >
> > > v2: Add support to only scan hwmon and drm PMUs if the event or PMU
> > > wildcard can match. Add a test as requested by Namhyung. Add file
> > > comments.
> > >
> > > v1:
> > > https://lore.kernel.org/lkml/20250211071727.364389-1-irogers@google.com/
> > >
> > > Ian Rogers (4):
> > >   perf parse-events: Avoid scanning PMUs that can't contain events
> > >   perf parse-events: Avoid scanning PMUs that can't match a wildcard
> > >   perf drm_pmu: Add a tool like PMU to expose DRM information
> > >   perf tests: Add a DRM PMU test
> > >
> > >  tools/perf/tests/shell/drm_pmu.sh |  78 ++++
> > >  tools/perf/util/Build             |   1 +
> > >  tools/perf/util/drm_pmu.c         | 689 ++++++++++++++++++++++++++++++
> > >  tools/perf/util/drm_pmu.h         |  39 ++
> > >  tools/perf/util/evsel.c           |   9 +
> > >  tools/perf/util/parse-events.c    |  30 +-
> > >  tools/perf/util/pmu.c             |  15 +
> > >  tools/perf/util/pmu.h             |   4 +-
> > >  tools/perf/util/pmus.c            | 101 ++++-
> > >  tools/perf/util/pmus.h            |   2 +
> > >  10 files changed, 952 insertions(+), 16 deletions(-)
> > >  create mode 100755 tools/perf/tests/shell/drm_pmu.sh
> > >  create mode 100644 tools/perf/util/drm_pmu.c
> > >  create mode 100644 tools/perf/util/drm_pmu.h
> > >
> > > --
> > > 2.49.0.504.g3bcea36a83-goog
> > >