[PATCH 4/9] KVM: arm64: PMU: Add counter_index_to_*reg() helpers

[Marc Zyngier <maz@xxxxxxxxxx>]

In order to reduce the boilerplate code, add two helpers returning
the counter register index (resp. the event register) in the vcpu
register file from the counter index.

Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
 arch/arm64/kvm/pmu-emul.c | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c
index 0ab6f59f433c..9be485d23416 100644
--- a/arch/arm64/kvm/pmu-emul.c
+++ b/arch/arm64/kvm/pmu-emul.c
@@ -75,6 +75,16 @@ static struct kvm_vcpu *kvm_pmc_to_vcpu(struct kvm_pmc *pmc)
 	return container_of(vcpu_arch, struct kvm_vcpu, arch);
 }
 
+static u32 counter_index_to_reg(u64 idx)
+{
+	return (idx == ARMV8_PMU_CYCLE_IDX) ? PMCCNTR_EL0 : PMEVCNTR0_EL0 + idx;
+}
+
+static u32 counter_index_to_evtreg(u64 idx)
+{
+	return (idx == ARMV8_PMU_CYCLE_IDX) ? PMCCFILTR_EL0 : PMEVTYPER0_EL0 + idx;
+}
+
 /**
  * kvm_pmu_get_counter_value - get PMU counter value
  * @vcpu: The vcpu pointer
@@ -89,8 +99,7 @@ u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx)
 	if (!kvm_vcpu_has_pmu(vcpu))
 		return 0;
 
-	reg = (select_idx == ARMV8_PMU_CYCLE_IDX)
-		? PMCCNTR_EL0 : PMEVCNTR0_EL0 + pmc->idx;
+	reg = counter_index_to_reg(select_idx);
 	counter = __vcpu_sys_reg(vcpu, reg);
 
 	/*
@@ -120,8 +129,7 @@ void kvm_pmu_set_counter_value(struct kvm_vcpu *vcpu, u64 select_idx, u64 val)
 	if (!kvm_vcpu_has_pmu(vcpu))
 		return;
 
-	reg = (select_idx == ARMV8_PMU_CYCLE_IDX)
-	      ? PMCCNTR_EL0 : PMEVCNTR0_EL0 + select_idx;
+	reg = counter_index_to_reg(select_idx);
 	__vcpu_sys_reg(vcpu, reg) += (s64)val - kvm_pmu_get_counter_value(vcpu, select_idx);
 
 	/* Recreate the perf event to reflect the updated sample_period */
@@ -156,10 +164,7 @@ static void kvm_pmu_stop_counter(struct kvm_vcpu *vcpu, struct kvm_pmc *pmc)
 
 	counter = kvm_pmu_get_counter_value(vcpu, pmc->idx);
 
-	if (pmc->idx == ARMV8_PMU_CYCLE_IDX)
-		reg = PMCCNTR_EL0;
-	else
-		reg = PMEVCNTR0_EL0 + pmc->idx;
+	reg = counter_index_to_reg(pmc->idx);
 
 	if (!kvm_pmu_idx_is_64bit(vcpu, pmc->idx))
 		counter = lower_32_bits(counter);
@@ -540,8 +545,7 @@ static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx)
 	struct perf_event_attr attr;
 	u64 eventsel, counter, reg, data;
 
-	reg = (select_idx == ARMV8_PMU_CYCLE_IDX)
-	      ? PMCCFILTR_EL0 : PMEVTYPER0_EL0 + pmc->idx;
+	reg = counter_index_to_evtreg(select_idx);
 	data = __vcpu_sys_reg(vcpu, reg);
 
 	kvm_pmu_stop_counter(vcpu, pmc);
@@ -627,8 +631,7 @@ void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data,
 	mask &= ~ARMV8_PMU_EVTYPE_EVENT;
 	mask |= kvm_pmu_event_mask(vcpu->kvm);
 
-	reg = (select_idx == ARMV8_PMU_CYCLE_IDX)
-	      ? PMCCFILTR_EL0 : PMEVTYPER0_EL0 + select_idx;
+	reg = counter_index_to_evtreg(select_idx);
 
 	__vcpu_sys_reg(vcpu, reg) = data & mask;
 
-- 
2.34.1