KVM: selftests: Add and use KVM helpers for x86 Family and Model

Add KVM variants of the x86 Family and Model helpers, and use them in the
PMU event filter test.  Open code the retrieval of KVM's supported CPUID
entry 0x1.0 in anticipation of dropping kvm_get_supported_cpuid_entry().

No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006005125.680782-12-seanjc@google.com

tools/testing/selftests/kvm/include/x86_64/processor.h

@@ -754,10 +754,27 @@ static inline void vcpu_xcrs_set(struct kvm_vcpu *vcpu, struct kvm_xcrs *xcrs)
 	vcpu_ioctl(vcpu, KVM_SET_XCRS, xcrs);
 }
 
+const struct kvm_cpuid_entry2 *get_cpuid_entry(const struct kvm_cpuid2 *cpuid,
+					       uint32_t function, uint32_t index);
 const struct kvm_cpuid2 *kvm_get_supported_cpuid(void);
 const struct kvm_cpuid2 *kvm_get_supported_hv_cpuid(void);
 const struct kvm_cpuid2 *vcpu_get_supported_hv_cpuid(struct kvm_vcpu *vcpu);
 
+static inline uint32_t kvm_cpu_fms(void)
+{
+	return get_cpuid_entry(kvm_get_supported_cpuid(), 0x1, 0)->eax;
+}
+
+static inline uint32_t kvm_cpu_family(void)
+{
+	return x86_family(kvm_cpu_fms());
+}
+
+static inline uint32_t kvm_cpu_model(void)
+{
+	return x86_model(kvm_cpu_fms());
+}
+
 bool kvm_cpuid_has(const struct kvm_cpuid2 *cpuid,
 		   struct kvm_x86_cpu_feature feature);
 
@@ -825,8 +842,6 @@ static inline struct kvm_cpuid2 *allocate_kvm_cpuid2(int nr_entries)
 	return cpuid;
 }
 
-const struct kvm_cpuid_entry2 *get_cpuid_entry(const struct kvm_cpuid2 *cpuid,
-					       uint32_t function, uint32_t index);
 void vcpu_init_cpuid(struct kvm_vcpu *vcpu, const struct kvm_cpuid2 *cpuid);
 void vcpu_set_hv_cpuid(struct kvm_vcpu *vcpu);
 

tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c

@@ -369,20 +369,19 @@ static bool use_intel_pmu(void)
 	       kvm_pmu_has(X86_PMU_FEATURE_BRANCH_INSNS_RETIRED);
 }
 
-static bool is_zen1(uint32_t eax)
+static bool is_zen1(uint32_t family, uint32_t model)
 {
-	return x86_family(eax) == 0x17 && x86_model(eax) <= 0x0f;
+	return family == 0x17 && model <= 0x0f;
 }
 
-static bool is_zen2(uint32_t eax)
+static bool is_zen2(uint32_t family, uint32_t model)
 {
-	return x86_family(eax) == 0x17 &&
-		x86_model(eax) >= 0x30 && x86_model(eax) <= 0x3f;
+	return family == 0x17 && model >= 0x30 && model <= 0x3f;
 }
 
-static bool is_zen3(uint32_t eax)
+static bool is_zen3(uint32_t family, uint32_t model)
 {
-	return x86_family(eax) == 0x19 && x86_model(eax) <= 0x0f;
+	return family == 0x19 && model <= 0x0f;
 }
 
 /*
@@ -395,13 +394,13 @@ static bool is_zen3(uint32_t eax)
  */
 static bool use_amd_pmu(void)
 {
-	const struct kvm_cpuid_entry2 *entry;
+	uint32_t family = kvm_cpu_family();
+	uint32_t model = kvm_cpu_model();
 
-	entry = kvm_get_supported_cpuid_entry(1);
 	return is_amd_cpu() &&
-		(is_zen1(entry->eax) ||
-		 is_zen2(entry->eax) ||
-		 is_zen3(entry->eax));
+		(is_zen1(family, model) ||
+		 is_zen2(family, model) ||
+		 is_zen3(family, model));
 }
 
 int main(int argc, char *argv[])