Re: [RFC 02/11] perf/core: Data structure to present hazard data

[Ravi Bangoria]

On 3/2/20 8:18 PM, Mark Rutland wrote:
> > diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
> > index 377d794d3105..ff252618ca93 100644
> > --- a/include/uapi/linux/perf_event.h
> > +++ b/include/uapi/linux/perf_event.h
> > @@ -142,8 +142,9 @@ enum perf_event_sample_format {
> >   	PERF_SAMPLE_REGS_INTR			= 1U << 18,
> >   	PERF_SAMPLE_PHYS_ADDR			= 1U << 19,
> >   	PERF_SAMPLE_AUX				= 1U << 20,
> > +	PERF_SAMPLE_PIPELINE_HAZ		= 1U << 21,
>
> Can we please have perf_event_open() reject this sample flag for PMUs
> without the new callback (introduced in the next patch)?
>
> That way it'll be possible to detect whether the PMU exposes this.

Sure. Will change it.

Ravi