Re: [PATCH V3 14/14] coresight: etm-perf: Add support for trace buffer format

Peter Zijlstra
2021-01-27T12:55:38Z

On Wed, Jan 27, 2021 at 02:25:38PM +0530, Anshuman Khandual wrote:

> It is possible to have a
> perf session where some events end up collecting the trace
> in TMC-ETR while the others in TRBE. Thus we need a way
> to identify the type of the trace for each AUX record.

> diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
> index 9a5ca45..169e6b3 100644
> --- a/include/uapi/linux/perf_event.h
> +++ b/include/uapi/linux/perf_event.h
> @@ -1111,6 +1111,10 @@ enum perf_callchain_context {
> #define PERF_AUX_FLAG_COLLISION 0x08 /* sample collided with another */
> #define PERF_AUX_FLAG_PMU_FORMAT_TYPE_MASK 0xff00 /* PMU specific trace format type */
>
> +/* CoreSight PMU AUX buffer formats */
> +#define PERF_AUX_FLAG_CORESIGHT_FORMAT_CORESIGHT 0x0000 /* Default for backward compatibility */
> +#define PERF_AUX_FLAG_CORESIGHT_FORMAT_RAW 0x0100 /* Raw format of the source */

Would CORESIGHT_FORMAT_ETR / CORESIGHT_FORMAT_TRBE be better names?