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

diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c
index 86e2328..04d0ceb 100644 (file)
--- a/arch/arm64/kernel/perf_event.c
+++ b/arch/arm64/kernel/perf_event.c
@@ -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);