KVM: x86/pmu: Drop "u64 eventsel" for reprogram_gp_counter()

Because inside reprogram_gp_counter() it is bound to assign the requested
eventel to pmc->eventsel, this assignment step can be moved forward, thus
simplifying the passing of parameters to "struct kvm_pmc *pmc" only.

No functional change intended.
Signed-off-by: Like Xu <likexu@tencent.com>
Message-Id: <20220518132512.37864-6-likexu@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/pmu.c

@@ -283,17 +283,16 @@ static bool check_pmu_event_filter(struct kvm_pmc *pmc)
 	return allow_event;
 }
 
-void reprogram_gp_counter(struct kvm_pmc *pmc, u64 eventsel)
+void reprogram_gp_counter(struct kvm_pmc *pmc)
 {
 	u64 config;
 	u32 type = PERF_TYPE_RAW;
 	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
+	u64 eventsel = pmc->eventsel;
 
 	if (eventsel & ARCH_PERFMON_EVENTSEL_PIN_CONTROL)
 		printk_once("kvm pmu: pin control bit is ignored\n");
 
-	pmc->eventsel = eventsel;
-
 	pmc_pause_counter(pmc);
 
 	if (!(eventsel & ARCH_PERFMON_EVENTSEL_ENABLE) || !pmc_is_enabled(pmc))
@@ -358,7 +357,7 @@ EXPORT_SYMBOL_GPL(reprogram_fixed_counter);
 void reprogram_counter(struct kvm_pmc *pmc)
 {
 	if (pmc_is_gp(pmc))
-		reprogram_gp_counter(pmc, pmc->eventsel);
+		reprogram_gp_counter(pmc);
 	else {
 		int idx = pmc->idx - INTEL_PMC_IDX_FIXED;
 		u8 ctrl = fixed_ctrl_field(pmc_to_pmu(pmc)->fixed_ctr_ctrl, idx);

arch/x86/kvm/pmu.h

@@ -173,7 +173,7 @@ static inline void kvm_init_pmu_capability(void)
 					     KVM_PMC_MAX_FIXED);
 }
 
-void reprogram_gp_counter(struct kvm_pmc *pmc, u64 eventsel);
+void reprogram_gp_counter(struct kvm_pmc *pmc);
 void reprogram_fixed_counter(struct kvm_pmc *pmc, u8 ctrl, int fixed_idx);
 void reprogram_counter(struct kvm_pmc *pmc);
 

arch/x86/kvm/svm/pmu.c

@@ -286,8 +286,10 @@ static int amd_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 	pmc = get_gp_pmc_amd(pmu, msr, PMU_TYPE_EVNTSEL);
 	if (pmc) {
 		data &= ~pmu->reserved_bits;
-		if (data != pmc->eventsel)
-			reprogram_gp_counter(pmc, data);
+		if (data != pmc->eventsel) {
+			pmc->eventsel = data;
+			reprogram_gp_counter(pmc);
+		}
 		return 0;
 	}
 

arch/x86/kvm/vmx/pmu_intel.c

@@ -492,7 +492,8 @@ static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 			    (pmu->raw_event_mask & HSW_IN_TX_CHECKPOINTED))
 				reserved_bits ^= HSW_IN_TX_CHECKPOINTED;
 			if (!(data & reserved_bits)) {
-				reprogram_gp_counter(pmc, data);
+				pmc->eventsel = data;
+				reprogram_gp_counter(pmc);
 				return 0;
 			}
 		} else if (intel_pmu_handle_lbr_msrs_access(vcpu, msr_info, false))