Commit 44fdf4ed authored by Qi Liu's avatar Qi Liu Committed by Will Deacon
Browse files

arm64: perf: Remove unnecessary event_idx check 



event_idx is obtained from armv8pmu_get_event_idx(), and this idx must be
between ARMV8_IDX_CYCLE_COUNTER and cpu_pmu->num_events. So it's unnecessary
to do this check. Let's remove it.

Signed-off-by: default avatarQi Liu <liuqi115@huawei.com>
Link: https://lore.kernel.org/r/1599213458-28394-1-git-send-email-liuqi115@huawei.com


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent d51eb416

arch/arm64/kernel/perf_event.c

+2 −18
Original line number Diff line number Diff line
@@ -310,8 +310,6 @@ static struct attribute_group armv8_pmuv3_format_attr_group = { 
 */

#define	ARMV8_IDX_CYCLE_COUNTER	0

#define	ARMV8_IDX_COUNTER0	1

#define	ARMV8_IDX_COUNTER_LAST(cpu_pmu) \

	(ARMV8_IDX_CYCLE_COUNTER + cpu_pmu->num_events - 1)





/*
@@ -368,12 +366,6 @@ static inline int armv8pmu_has_overflowed(u32 pmovsr) 
	return pmovsr & ARMV8_PMU_OVERFLOWED_MASK;

}



static inline int armv8pmu_counter_valid(struct arm_pmu *cpu_pmu, int idx)

{

	return idx >= ARMV8_IDX_CYCLE_COUNTER &&

		idx <= ARMV8_IDX_COUNTER_LAST(cpu_pmu);

}



static inline int armv8pmu_counter_has_overflowed(u32 pmnc, int idx)

{

	return pmnc & BIT(ARMV8_IDX_TO_COUNTER(idx));
@@ -443,15 +435,11 @@ static u64 armv8pmu_unbias_long_counter(struct perf_event *event, u64 value) 


static u64 armv8pmu_read_counter(struct perf_event *event)

{

	struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu);

	struct hw_perf_event *hwc = &event->hw;

	int idx = hwc->idx;

	u64 value = 0;



	if (!armv8pmu_counter_valid(cpu_pmu, idx))

		pr_err("CPU%u reading wrong counter %d\n",

			smp_processor_id(), idx);

	else if (idx == ARMV8_IDX_CYCLE_COUNTER)

	if (idx == ARMV8_IDX_CYCLE_COUNTER)

		value = read_sysreg(pmccntr_el0);

	else

		value = armv8pmu_read_hw_counter(event);
@@ -480,16 +468,12 @@ static inline void armv8pmu_write_hw_counter(struct perf_event *event, 


static void armv8pmu_write_counter(struct perf_event *event, u64 value)

{

	struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu);

	struct hw_perf_event *hwc = &event->hw;

	int idx = hwc->idx;



	value = armv8pmu_bias_long_counter(event, value);



	if (!armv8pmu_counter_valid(cpu_pmu, idx))

		pr_err("CPU%u writing wrong counter %d\n",

			smp_processor_id(), idx);

	else if (idx == ARMV8_IDX_CYCLE_COUNTER)

	if (idx == ARMV8_IDX_CYCLE_COUNTER)

		write_sysreg(value, pmccntr_el0);

	else

		armv8pmu_write_hw_counter(event, value);

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