[PATCH v20 03/11] perf: arm_pmuv3: Don't disable counter in armv8pmu_enable_event()

Rob Herring (Arm) robh at kernel.org
Tue Feb 18 12:39:58 PST 2025


From: Mark Rutland <mark.rutland at arm.com>

Currently armv8pmu_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
armv8pmu_enable_event() is called.

Remove the redundant call to armv8pmu_disable_event_counter(). At the
same time, remove the comment immeditately above as everything it says
is obvious from the function names below.

Signed-off-by: Mark Rutland <mark.rutland at arm.com>
Signed-off-by: "Rob Herring (Arm)" <robh at kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual at arm.com>
---
 drivers/perf/arm_pmuv3.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/drivers/perf/arm_pmuv3.c b/drivers/perf/arm_pmuv3.c
index 9ebc950559c0..5406b9ca591a 100644
--- a/drivers/perf/arm_pmuv3.c
+++ b/drivers/perf/arm_pmuv3.c
@@ -795,11 +795,6 @@ static void armv8pmu_enable_user_access(struct arm_pmu *cpu_pmu)
 
 static void armv8pmu_enable_event(struct perf_event *event)
 {
-	/*
-	 * Enable counter and interrupt, and set the counter to count
-	 * the event that we're interested in.
-	 */
-	armv8pmu_disable_event_counter(event);
 	armv8pmu_write_event_type(event);
 	armv8pmu_enable_event_irq(event);
 	armv8pmu_enable_event_counter(event);

-- 
2.47.2




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