Re: [RFC 0/4] perf: Per PMU access controls (paranoid setting)

[Tvrtko Ursulin]

On 12/09/18 07:52, Alexey Budankov wrote:
> Hi,
>
> Is there any plans or may be even progress on that so far?

It's hanging in the back of my mind. AFAIR after last round there was a 
build failure or two to fix on more exotic (to me) hardware, and Jiri 
Olsa provided a tools/perf snippet supporting the feature.

But essentially I haven't done any work on it since due not seeing the 
route to upstream. :( In other words, will someone review it and will 
that r-b make it have a chance of getting into some tree. If I had a 
clear statement from someone with authority in these aspects I would 
progress it, but otherwise it felt like it's not going anywhere.

Regards,

Tvrtko


> Thanks,
> Alexey
>
> On 26.06.2018 18:36, Tvrtko Ursulin wrote:
> > From: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
> >
> > For situations where sysadmins might want to allow different level of
> > access control for different PMUs, we start creating per-PMU
> > perf_event_paranoid controls in sysfs.
> >
> > These work in equivalent fashion as the existing perf_event_paranoid
> > sysctl, which now becomes the parent control for each PMU.
> >
> > On PMU registration the global/parent value will be inherited by each PMU,
> > as it will be propagated to all registered PMUs when the sysctl is
> > updated.
> >
> > At any later point individual PMU access controls, located in
> > <sysfs>/device/<pmu-name>/perf_event_paranoid, can be adjusted to achieve
> > fine grained access control.
> >
> > Discussion from previous posting:
> > https://lkml.org/lkml/2018/5/21/156
> >
> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> > Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> > Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
> > Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
> > Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
> > Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
> > Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
> > Cc: Madhavan Srinivasan <maddy@xxxxxxxxxxxxxxxxxx>
> > Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> > Cc: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx>
> > Cc: linux-kernel@xxxxxxxxxxxxxxx
> > Cc: x86@xxxxxxxxxx
> >
> > Tvrtko Ursulin (4):
> >    perf: Move some access checks later in perf_event_open
> >    perf: Pass pmu pointer to perf_paranoid_* helpers
> >    perf: Allow per PMU access control
> >    perf Documentation: Document the per PMU perf_event_paranoid interface
> >
> >   .../sysfs-bus-event_source-devices-events     |  14 +++
> >   arch/powerpc/perf/core-book3s.c               |   2 +-
> >   arch/x86/events/intel/bts.c                   |   2 +-
> >   arch/x86/events/intel/core.c                  |   2 +-
> >   arch/x86/events/intel/p4.c                    |   2 +-
> >   include/linux/perf_event.h                    |  18 ++-
> >   kernel/events/core.c                          | 104 +++++++++++++++---
> >   kernel/sysctl.c                               |   4 +-
> >   kernel/trace/trace_event_perf.c               |   6 +-
> >   9 files changed, 123 insertions(+), 31 deletions(-)