Re: [PATCH 1/3] perf/x86: Add new event for AUX output counter index

[Peter Zijlstra]

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?