Re: [PATCH V13 - RESEND 01/10] drivers: perf: arm_pmu: Add new sched_task() callback

[Anshuman Khandual]

Hello Will,

I am just wondering - would it be possible for you to take this pre-requisite
patch stand alone for the upcoming merge window. This has been acked by Mark
earlier. Besides, I am also working on your other suggestions on the series,
and will respond soon. Thank you.

- Anshuman

On 7/11/23 13:54, Anshuman Khandual wrote:
> This adds armpmu_sched_task(), as generic pmu's sched_task() override which
> in turn can utilize a new arm_pmu.sched_task() callback when available from
> the arm_pmu instance. This new callback will be used while enabling BRBE in
> ARMV8 PMU.
> 
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Will Deacon <will@xxxxxxxxxx>
> Cc: Mark Rutland <mark.rutland@xxxxxxx>
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Tested-by: James Clark <james.clark@xxxxxxx>
> Acked-by: Mark Rutland <mark.rutland@xxxxxxx>
> Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
> ---
>  drivers/perf/arm_pmu.c       | 9 +++++++++
>  include/linux/perf/arm_pmu.h | 1 +
>  2 files changed, 10 insertions(+)
> 
> diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
> index f6ccb2cd4dfc..c0475a96c2a0 100644
> --- a/drivers/perf/arm_pmu.c
> +++ b/drivers/perf/arm_pmu.c
> @@ -519,6 +519,14 @@ static int armpmu_event_init(struct perf_event *event)
>  	return __hw_perf_event_init(event);
>  }
>  
> +static void armpmu_sched_task(struct perf_event_pmu_context *pmu_ctx, bool sched_in)
> +{
> +	struct arm_pmu *armpmu = to_arm_pmu(pmu_ctx->pmu);
> +
> +	if (armpmu->sched_task)
> +		armpmu->sched_task(pmu_ctx, sched_in);
> +}
> +
>  static void armpmu_enable(struct pmu *pmu)
>  {
>  	struct arm_pmu *armpmu = to_arm_pmu(pmu);
> @@ -865,6 +873,7 @@ struct arm_pmu *armpmu_alloc(void)
>  	}
>  
>  	pmu->pmu = (struct pmu) {
> +		.sched_task	= armpmu_sched_task,
>  		.pmu_enable	= armpmu_enable,
>  		.pmu_disable	= armpmu_disable,
>  		.event_init	= armpmu_event_init,
> diff --git a/include/linux/perf/arm_pmu.h b/include/linux/perf/arm_pmu.h
> index a0801f68762b..3d3bd944d630 100644
> --- a/include/linux/perf/arm_pmu.h
> +++ b/include/linux/perf/arm_pmu.h
> @@ -102,6 +102,7 @@ struct arm_pmu {
>  	void		(*stop)(struct arm_pmu *);
>  	void		(*reset)(void *);
>  	int		(*map_event)(struct perf_event *event);
> +	void		(*sched_task)(struct perf_event_pmu_context *pmu_ctx, bool sched_in);
>  	int		num_events;
>  	bool		secure_access; /* 32-bit ARM only */
>  #define ARMV8_PMUV3_MAX_COMMON_EVENTS		0x40