Re: [PATCH V3 13/14] perf: aux: Add flags for the buffer format

Peter Zijlstra
2021-01-27T12:53:47Z

On Wed, Jan 27, 2021 at 02:25:37PM +0530, Anshuman Khandual wrote:
> From: Suzuki K Poulose <suzuki.poulose@arm.com>
>
> Allocate a byte for advertising the PMU specific format type
> of the given AUX record. A PMU could end up providing hardware
> trace data in multiple format in a single session.
>
> e.g, The format of hardware buffer produced by CoreSight ETM
> PMU depends on the type of the "sink" device used for collection
> for an event (Traditional TMC-ETR/Bs with formatting or
> TRBEs without any formatting).

Acked-by: Peter Ziljstra <peterz@infradead.org>

> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
> ---
> include/uapi/linux/perf_event.h | 9 +++++----
> 1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
> index b15e344..9a5ca45 100644
> --- a/include/uapi/linux/perf_event.h
> +++ b/include/uapi/linux/perf_event.h
> @@ -1105,10 +1105,11 @@ enum perf_callchain_context {
> /**
> * PERF_RECORD_AUX::flags bits
> */
> -#define PERF_AUX_FLAG_TRUNCATED 0x01 /* record was truncated to fit */
> -#define PERF_AUX_FLAG_OVERWRITE 0x02 /* snapshot from overwrite mode */
> -#define PERF_AUX_FLAG_PARTIAL 0x04 /* record contains gaps */
> -#define PERF_AUX_FLAG_COLLISION 0x08 /* sample collided with another */
> +#define PERF_AUX_FLAG_TRUNCATED 0x01 /* record was truncated to fit */
> +#define PERF_AUX_FLAG_OVERWRITE 0x02 /* snapshot from overwrite mode */
> +#define PERF_AUX_FLAG_PARTIAL 0x04 /* record contains gaps */
> +#define PERF_AUX_FLAG_COLLISION 0x08 /* sample collided with another */
> +#define PERF_AUX_FLAG_PMU_FORMAT_TYPE_MASK 0xff00 /* PMU specific trace format type */
>
> #define PERF_FLAG_FD_NO_GROUP (1UL << 0)
> #define PERF_FLAG_FD_OUTPUT (1UL << 1)
> --
> 2.7.4