[PATCH v20 06/11] perf: apple_m1: Don't disable counter in m1_pmu_enable_event()

Rob Herring (Arm) robh at kernel.org
Tue Feb 18 12:40:01 PST 2025


Currently m1_pmu_enable_event() starts by disabling the event counter
it has been asked to enable. This should not be necessary as the
counter (and the PMU as a whole) should not be active when
m1_pmu_enable_event() is called.

Cc: Marc Zyngier <maz at kernel.org>
Signed-off-by: "Rob Herring (Arm)" <robh at kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual at arm.com>
---
 drivers/perf/apple_m1_cpu_pmu.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/perf/apple_m1_cpu_pmu.c b/drivers/perf/apple_m1_cpu_pmu.c
index 06fd317529fc..39349ecec3c1 100644
--- a/drivers/perf/apple_m1_cpu_pmu.c
+++ b/drivers/perf/apple_m1_cpu_pmu.c
@@ -396,10 +396,6 @@ static void m1_pmu_enable_event(struct perf_event *event)
 	user = event->hw.config_base & M1_PMU_CFG_COUNT_USER;
 	kernel = event->hw.config_base & M1_PMU_CFG_COUNT_KERNEL;
 
-	m1_pmu_disable_counter_interrupt(event->hw.idx);
-	m1_pmu_disable_counter(event->hw.idx);
-	isb();
-
 	m1_pmu_configure_counter(event->hw.idx, evt, user, kernel);
 	m1_pmu_enable_counter(event->hw.idx);
 	m1_pmu_enable_counter_interrupt(event->hw.idx);

-- 
2.47.2




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