Re: [PATCH] perf/core: Introduce cpuctx->cgrp_ctx_list

[Namhyung Kim]

On Mon, Oct 9, 2023 at 9:57 PM Namhyung Kim <namhyung@xxxxxxxxxx> wrote:
>
> Hi Peter,
>
> On Mon, Oct 9, 2023 at 2:04 PM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> >
> > On Wed, Oct 04, 2023 at 09:32:24AM -0700, Namhyung Kim wrote:
> >
> > > Yeah, I know.. but I couldn't come up with a better solution.
> >
> > Not been near a compiler, and haven't fully thought it through, but
> > could something like the work work?
>
> Thanks for the patch, I think it'd work.  Let me test it
> and get back to you.

I worked well but contained a typo.  See below.

Which way do you want to process this change?  Do I send it again
with your S-o-b or will you apply it by yourself?  Either is fine, just
let me know.  In case of latter, you can add

Tested-by: Namhyung Kim <namhyung@xxxxxxxxxx>

> >
> >
> > ---
> >  include/linux/perf_event.h |   1 +
> >  kernel/events/core.c       | 115 +++++++++++++++++++++++----------------------
> >  2 files changed, 61 insertions(+), 55 deletions(-)
> >
> > diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
> > index f31f962a6445..0367d748fae0 100644
> > --- a/include/linux/perf_event.h
> > +++ b/include/linux/perf_event.h
> > @@ -878,6 +878,7 @@ struct perf_event_pmu_context {
> >         unsigned int                    embedded : 1;
> >
> >         unsigned int                    nr_events;
> > +       unsigned int                    nr_cgroups;
> >
> >         atomic_t                        refcount; /* event <-> epc */
> >         struct rcu_head                 rcu_head;
> > diff --git a/kernel/events/core.c b/kernel/events/core.c
> > index 708d474c2ede..f3d5d47ecdfc 100644
> > --- a/kernel/events/core.c
> > +++ b/kernel/events/core.c
> > @@ -375,6 +375,7 @@ enum event_type_t {
> >         EVENT_TIME = 0x4,
> >         /* see ctx_resched() for details */
> >         EVENT_CPU = 0x8,
> > +       EVENT_CGROUP = 0x10,
> >         EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED,
> >  };
> >
> > @@ -684,20 +685,26 @@ do {                                                                      \
> >         ___p;                                                           \
> >  })
> >
> > -static void perf_ctx_disable(struct perf_event_context *ctx)
> > +static void perf_ctx_disable(struct perf_event_context *ctx, bool cgroup)
> >  {
> >         struct perf_event_pmu_context *pmu_ctx;
> >
> > -       list_for_each_entry(pmu_ctx, &ctx->pmu_ctx_list, pmu_ctx_entry)
> > +       list_for_each_entry(pmu_ctx, &ctx->pmu_ctx_list, pmu_ctx_entry) {
> > +               if (cgroup && !pmu_ctx->nr_cgroups)
> > +                       continue;
> >                 perf_pmu_disable(pmu_ctx->pmu);
> > +       }
> >  }
> >
> > -static void perf_ctx_enable(struct perf_event_context *ctx)
> > +static void perf_ctx_enable(struct perf_event_context *ctx. bool cgroup)

s/./,/

Thanks,
Namhyung


> >  {
> >         struct perf_event_pmu_context *pmu_ctx;
> >
> > -       list_for_each_entry(pmu_ctx, &ctx->pmu_ctx_list, pmu_ctx_entry)
> > +       list_for_each_entry(pmu_ctx, &ctx->pmu_ctx_list, pmu_ctx_entry) {
> > +               if (cgroup && !pmu_ctx->nr_cgroups)
> > +                       continue;
> >                 perf_pmu_enable(pmu_ctx->pmu);
> > +       }
> >  }