[RFC PATCH 08/15] ARM: perf: remove unnecessary armpmu->stop

Mark Rutland mark.rutland at arm.com
Mon Aug 15 09:55:09 EDT 2011


As armpmu_disable will call armpmu->stop when the last event has been
removed, this is pointless and simply adds to the noise when debugging.
Additionally, due to this call occurring in a preemptible context, this
is problematic for per-cpu locking of PMU registers (where we will
attempt to access per-cpu spinlock for use with raw_spin_lock_irqsave).

This patch removes the call to armpmu->stop.

Signed-off-by: Mark Rutland <mark.rutland at arm.com>
Reviewed-by: Will Deacon <will.deacon at arm.com>
---
 arch/arm/kernel/perf_event.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index 9d6ac99..5ce6c33 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -396,7 +396,6 @@ armpmu_release_hardware(void)
 			free_irq(irq, NULL);
 	}
 
-	armpmu->stop();
 	release_pmu(ARM_PMU_DEVICE_CPU);
 }
 
-- 
1.7.0.4




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