Re: [PATCH 03/12] perf/x86/intel: Add perf core PMU support for Sapphire Rapids

From: Peter Zijlstra
Date: Tue Jan 26 2021 - 09:46:44 EST


On Tue, Jan 19, 2021 at 12:38:22PM -0800, kan.liang@xxxxxxxxxxxxxxx wrote:
> @@ -2319,6 +2474,17 @@ static void __icl_update_topdown_event(struct perf_event *event,
> {
> u64 delta, last = 0;
>
> + /*
> + * Although the unsupported topdown events are not exposed to users,
> + * users may mistakenly use the unsupported events via RAW format.
> + * For example, using L2 topdown event, cpu/event=0x00,umask=0x84/,
> + * on Ice Lake. In this case, the scheduler follows the unknown
> + * event handling and assigns a GP counter to the event.
> + * Check the case, and avoid updating unsupported events.
> + */
> + if (event->hw.idx < INTEL_PMC_IDX_FIXED)
> + return;
> +
> delta = icl_get_topdown_value(event, slots, metrics);
> if (last_slots)
> last = icl_get_topdown_value(event, last_slots, last_metrics);

Is this a separate patch?