Messages in this thread | | | Date | Wed, 30 Jun 2021 13:04:28 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH 1/3] perf/x86: Add new event for AUX output counter index |
| |
On Wed, Jun 30, 2021 at 12:21:07PM +0300, Adrian Hunter wrote: > On 25/06/21 4:15 pm, Peter Zijlstra wrote: > > On Wed, Jun 09, 2021 at 05:20:53PM +0300, Adrian Hunter wrote: > > > >> +static void intel_pmu_report_aux_output_id(struct perf_event *event) > >> +{ > >> + struct hw_perf_event *hwc = &event->hw; > >> + > >> + /* > >> + * So long as all PEBS-via-PT events for a recording session are > >> + * scheduled together, then only changes to hwc->idx need be reported. > >> + */ > >> + if (hwc->idx != hwc->idx_reported) { > >> + hwc->idx_reported = hwc->idx; > >> + perf_report_aux_output_id(event, hwc->idx); > >> + } > >> +} > > > > AFAICT you want a callback in x86_assign_hw_event(), is that so? > > > > Yes, or open-coded e.g. > > diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c > index 8f71dd72ef95..46dac45298d1 100644 > --- a/arch/x86/events/core.c > +++ b/arch/x86/events/core.c > @@ -1207,6 +1207,11 @@ static int collect_events(struct cpu_hw_events *cpuc, struct perf_event *leader, > return n; > } > > +static inline bool report_aux_output_id(struct perf_event *event) > +{ > + return is_pebs_pt(event); > +} > + > static inline void x86_assign_hw_event(struct perf_event *event, > struct cpu_hw_events *cpuc, int i) > { > @@ -1217,6 +1222,9 @@ static inline void x86_assign_hw_event(struct perf_event *event, > hwc->last_cpu = smp_processor_id(); > hwc->last_tag = ++cpuc->tags[i]; > > + if (report_aux_output_id(event)) > + perf_report_aux_output_id(event, idx); > + > switch (hwc->idx) { > case INTEL_PMC_IDX_FIXED_BTS: > case INTEL_PMC_IDX_FIXED_VLBR:
Right, bit yuck, but I suppose it works. The alternative is something like:
static_call_cond(x86_pmu_assign)(event, idx);
but I'm not sure that's worth it, but it avoids stuffing even more intel specific bits into the core.
| |