Re: [PATCH V2 4/6] x86/intel_rdt: Add helper to obtain performance counter index

[Peter Zijlstra]

On Thu, Aug 16, 2018 at 01:16:07PM -0700, Reinette Chatre wrote:

> +static inline int x86_perf_rdpmc_ctr_get(struct perf_event *event)
> +{
> +	lockdep_assert_irqs_disabled();
> +
> +	return IS_ERR_OR_NULL(event) ? -1 : event->hw.event_base_rdpmc;
> +}

That should be in arch/x86/include/asm/perf_event.h if anywhere. Also,
call the thing x86_perf_rdpmc_index(), that's consistent with the other
naming.

I don't think there's any point in testing for !event, this is an
interface that mandates you know wth you're doing anyway.