[PATCH V8 1/6] drivers: perf: arm_pmu: Add new sched_task() callback

[Anshuman Khandual <anshuman.khandual@arm.com>]

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
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 9b593f985805..14a3ed3bdb0b 100644
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c
@@ -517,6 +517,14 @@ 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);
@@ -873,6 +881,7 @@ 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 ef914a600087..2a9d07cee927 100644
--- a/include/linux/perf/arm_pmu.h
+++ b/include/linux/perf/arm_pmu.h
@@ -101,6 +101,7 @@ struct arm_pmu {
 	void		(*reset)(void *);
 	int		(*map_event)(struct perf_event *event);
 	bool		(*filter)(struct pmu *pmu, int cpu);
+	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
-- 
2.25.1