Re: [PATCH V2 1/2] perf: Sample additional clock value

[David Ahern <dsahern@gmail.com>]

On 2/20/15 5:44 AM, Adrian Hunter wrote:
> diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
> index efe2d2d..9385140 100644
> --- a/include/linux/perf_event.h
> +++ b/include/linux/perf_event.h
> @@ -655,7 +655,7 @@ extern void perf_pmu_migrate_context(struct pmu *pmu,
>   				int src_cpu, int dst_cpu);
>   extern u64 perf_event_read_value(struct perf_event *event,
>   				 u64 *enabled, u64 *running);
> -
> +u64 perf_sample_clock_pt(void);

Core functions should not be arch specific. PT == x86.


> @@ -4915,6 +4918,11 @@ perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size,
>   	}
>   }
>
> +u64 __weak perf_sample_clock_pt(void)
> +{
> +	return 0;
> +}
> +
>   static void __perf_event_header__init_id(struct perf_event_header *header,
>   					 struct perf_sample_data *data,
>   					 struct perf_event *event)
> @@ -4943,6 +4951,16 @@ static void __perf_event_header__init_id(struct perf_event_header *header,
>   		data->cpu_entry.cpu	 = raw_smp_processor_id();
>   		data->cpu_entry.reserved = 0;
>   	}
> +
> +	if (sample_type & PERF_SAMPLE_CLOCK) {
> +		switch (event->attr.clock) {
> +		case PERF_SAMPLE_CLOCK_PT:
> +			data->clock = perf_sample_clock_pt();
> +			break;
> +		default:
> +			data->clock = 0;
> +		}
> +	}
>   }
>

Ditto here. This should be transparent for arch specific clocks.

David