diff mbox series

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

Message ID 20230711082455.215983-2-anshuman.khandual@arm.com
State New
Headers
Series arm64/perf: Enable branch stack sampling |

Commit Message

Anshuman Khandual July 11, 2023, 8:24 a.m. UTC 
  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@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Tested-by: James Clark <james.clark@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
 drivers/perf/arm_pmu.c       | 9 +++++++++
 include/linux/perf/arm_pmu.h | 1 +
 2 files changed, 10 insertions(+)

Comments

Anshuman Khandual Aug. 10, 2023, 5:05 a.m. UTC | #1 
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@arm.com>
> Cc: Will Deacon <will@kernel.org>
> Cc: Mark Rutland <mark.rutland@arm.com>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org
> Tested-by: James Clark <james.clark@arm.com>
> Acked-by: Mark Rutland <mark.rutland@arm.com>
> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
> ---
>  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
Will Deacon Aug. 10, 2023, 9:41 a.m. UTC | #2 
On Thu, Aug 10, 2023 at 10:35:42AM +0530, Anshuman Khandual wrote:
> 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.

I can if it helps in some way, but I'm not seeing how it does. Can't you
just carry this along with the BRBE changes that use it? How does it benefit
anybody on its own?

Will
Anshuman Khandual Aug. 10, 2023, 11:49 a.m. UTC | #3 
On 8/10/23 15:11, Will Deacon wrote:
> On Thu, Aug 10, 2023 at 10:35:42AM +0530, Anshuman Khandual wrote:
>> 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.
> 
> I can if it helps in some way, but I'm not seeing how it does. Can't you
> just carry this along with the BRBE changes that use it? How does it benefit
> anybody on its own?
It might help de-clutter our conversation and focus on BRBE specific
implementation stuff next time around in V14. Also this change here
is quite harmless for any other thing, hence without much risk.
diff mbox series

Patch

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