KVM: x86/pmu: Introduce distinct macros for GP/fixed counter max number

Refine the macros which define maximum General Purpose (GP) and fixed
counter numbers.

Currently the macro KVM_INTEL_PMC_MAX_GENERIC is used to represent the
maximum supported General Purpose (GP) counter number ambiguously across
Intel and AMD platforms. This would cause issues if AMD begins to support
more GP counters than Intel.

Thus a bunch of new macros including vendor specific and vendor
independent are introduced to replace the old macros. The vendor
independent macros are used in x86 common code to hide vendor difference
and eliminate the ambiguity.

No logic changes are introduced in this patch.

Signed-off-by: Dapeng Mi <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Co-developed-by: Sean Christopherson <[email protected]>
Signed-off-by: Sean Christopherson <[email protected]>

Author: Dapeng Mi

arch/x86/include/asm/kvm_host.h

@@ -533,12 +533,16 @@ struct kvm_pmc {
 };
 
 /* More counters may conflict with other existing Architectural MSRs */
-#define KVM_INTEL_PMC_MAX_GENERIC	8
-#define MSR_ARCH_PERFMON_PERFCTR_MAX	(MSR_ARCH_PERFMON_PERFCTR0 + KVM_INTEL_PMC_MAX_GENERIC - 1)
-#define MSR_ARCH_PERFMON_EVENTSEL_MAX	(MSR_ARCH_PERFMON_EVENTSEL0 + KVM_INTEL_PMC_MAX_GENERIC - 1)
-#define KVM_PMC_MAX_FIXED	3
-#define MSR_ARCH_PERFMON_FIXED_CTR_MAX	(MSR_ARCH_PERFMON_FIXED_CTR0 + KVM_PMC_MAX_FIXED - 1)
-#define KVM_AMD_PMC_MAX_GENERIC	6
+#define KVM_MAX(a, b)	((a) >= (b) ? (a) : (b))
+#define KVM_MAX_NR_INTEL_GP_COUNTERS	8
+#define KVM_MAX_NR_AMD_GP_COUNTERS	6
+#define KVM_MAX_NR_GP_COUNTERS		KVM_MAX(KVM_MAX_NR_INTEL_GP_COUNTERS, \
+						KVM_MAX_NR_AMD_GP_COUNTERS)
+
+#define KVM_MAX_NR_INTEL_FIXED_COUTNERS	3
+#define KVM_MAX_NR_AMD_FIXED_COUTNERS	0
+#define KVM_MAX_NR_FIXED_COUNTERS	KVM_MAX(KVM_MAX_NR_INTEL_FIXED_COUTNERS, \
+						KVM_MAX_NR_AMD_FIXED_COUTNERS)
 
 struct kvm_pmu {
 	u8 version;
@@ -554,8 +558,8 @@ struct kvm_pmu {
 	u64 global_status_rsvd;
 	u64 reserved_bits;
 	u64 raw_event_mask;
-	struct kvm_pmc gp_counters[KVM_INTEL_PMC_MAX_GENERIC];
-	struct kvm_pmc fixed_counters[KVM_PMC_MAX_FIXED];
+	struct kvm_pmc gp_counters[KVM_MAX_NR_GP_COUNTERS];
+	struct kvm_pmc fixed_counters[KVM_MAX_NR_FIXED_COUNTERS];
 
 	/*
 	 * Overlay the bitmap with a 64-bit atomic so that all bits can be

arch/x86/kvm/pmu.c

@@ -69,7 +69,7 @@ static const struct x86_cpu_id vmx_pebs_pdist_cpu[] = {
  *        code. Each pmc, stored in kvm_pmc.idx field, is unique across
  *        all perf counters (both gp and fixed). The mapping relationship
  *        between pmc and perf counters is as the following:
- *        * Intel: [0 .. KVM_INTEL_PMC_MAX_GENERIC-1] <=> gp counters
+ *        * Intel: [0 .. KVM_MAX_NR_INTEL_GP_COUNTERS-1] <=> gp counters
  *                 [KVM_FIXED_PMC_BASE_IDX .. KVM_FIXED_PMC_BASE_IDX + 2] <=> fixed
  *        * AMD:   [0 .. AMD64_NUM_COUNTERS-1] and, for families 15H
  *          and later, [0 .. AMD64_NUM_COUNTERS_CORE-1] <=> gp counters

arch/x86/kvm/pmu.h

@@ -219,7 +219,7 @@ static inline void kvm_init_pmu_capability(const struct kvm_pmu_ops *pmu_ops)
 	kvm_pmu_cap.num_counters_gp = min(kvm_pmu_cap.num_counters_gp,
 					  pmu_ops->MAX_NR_GP_COUNTERS);
 	kvm_pmu_cap.num_counters_fixed = min(kvm_pmu_cap.num_counters_fixed,
-					     KVM_PMC_MAX_FIXED);
+					     KVM_MAX_NR_FIXED_COUNTERS);
 
 	kvm_pmu_eventsel.INSTRUCTIONS_RETIRED =
 		perf_get_hw_event_config(PERF_COUNT_HW_INSTRUCTIONS);

arch/x86/kvm/svm/pmu.c

@@ -217,10 +217,9 @@ static void amd_pmu_init(struct kvm_vcpu *vcpu)
 	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 	int i;
 
-	BUILD_BUG_ON(KVM_AMD_PMC_MAX_GENERIC > AMD64_NUM_COUNTERS_CORE);
-	BUILD_BUG_ON(KVM_AMD_PMC_MAX_GENERIC > INTEL_PMC_MAX_GENERIC);
+	BUILD_BUG_ON(KVM_MAX_NR_AMD_GP_COUNTERS > AMD64_NUM_COUNTERS_CORE);
 
-	for (i = 0; i < KVM_AMD_PMC_MAX_GENERIC ; i++) {
+	for (i = 0; i < KVM_MAX_NR_AMD_GP_COUNTERS; i++) {
 		pmu->gp_counters[i].type = KVM_PMC_GP;
 		pmu->gp_counters[i].vcpu = vcpu;
 		pmu->gp_counters[i].idx = i;
@@ -238,6 +237,6 @@ struct kvm_pmu_ops amd_pmu_ops __initdata = {
 	.refresh = amd_pmu_refresh,
 	.init = amd_pmu_init,
 	.EVENTSEL_EVENT = AMD64_EVENTSEL_EVENT,
-	.MAX_NR_GP_COUNTERS = KVM_AMD_PMC_MAX_GENERIC,
+	.MAX_NR_GP_COUNTERS = KVM_MAX_NR_AMD_GP_COUNTERS,
 	.MIN_NR_GP_COUNTERS = AMD64_NUM_COUNTERS,
 };

arch/x86/kvm/vmx/pmu_intel.c

@@ -436,8 +436,8 @@ static __always_inline u64 intel_get_fixed_pmc_eventsel(unsigned int index)
 	};
 	u64 eventsel;
 
-	BUILD_BUG_ON(ARRAY_SIZE(fixed_pmc_perf_ids) != KVM_PMC_MAX_FIXED);
-	BUILD_BUG_ON(index >= KVM_PMC_MAX_FIXED);
+	BUILD_BUG_ON(ARRAY_SIZE(fixed_pmc_perf_ids) != KVM_MAX_NR_INTEL_FIXED_COUTNERS);
+	BUILD_BUG_ON(index >= KVM_MAX_NR_INTEL_FIXED_COUTNERS);
 
 	/*
 	 * Yell if perf reports support for a fixed counter but perf doesn't
@@ -570,14 +570,14 @@ static void intel_pmu_init(struct kvm_vcpu *vcpu)
 	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 	struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
 
-	for (i = 0; i < KVM_INTEL_PMC_MAX_GENERIC; i++) {
+	for (i = 0; i < KVM_MAX_NR_INTEL_GP_COUNTERS; i++) {
 		pmu->gp_counters[i].type = KVM_PMC_GP;
 		pmu->gp_counters[i].vcpu = vcpu;
 		pmu->gp_counters[i].idx = i;
 		pmu->gp_counters[i].current_config = 0;
 	}
 
-	for (i = 0; i < KVM_PMC_MAX_FIXED; i++) {
+	for (i = 0; i < KVM_MAX_NR_INTEL_FIXED_COUTNERS; i++) {
 		pmu->fixed_counters[i].type = KVM_PMC_FIXED;
 		pmu->fixed_counters[i].vcpu = vcpu;
 		pmu->fixed_counters[i].idx = i + KVM_FIXED_PMC_BASE_IDX;
@@ -737,6 +737,6 @@ struct kvm_pmu_ops intel_pmu_ops __initdata = {
 	.deliver_pmi = intel_pmu_deliver_pmi,
 	.cleanup = intel_pmu_cleanup,
 	.EVENTSEL_EVENT = ARCH_PERFMON_EVENTSEL_EVENT,
-	.MAX_NR_GP_COUNTERS = KVM_INTEL_PMC_MAX_GENERIC,
+	.MAX_NR_GP_COUNTERS = KVM_MAX_NR_INTEL_GP_COUNTERS,
 	.MIN_NR_GP_COUNTERS = 1,
 };

arch/x86/kvm/x86.c

@@ -1473,7 +1473,7 @@ static const u32 msrs_to_save_pmu[] = {
 	MSR_CORE_PERF_GLOBAL_CTRL,
 	MSR_IA32_PEBS_ENABLE, MSR_IA32_DS_AREA, MSR_PEBS_DATA_CFG,
 
-	/* This part of MSRs should match KVM_INTEL_PMC_MAX_GENERIC. */
+	/* This part of MSRs should match KVM_MAX_NR_INTEL_GP_COUNTERS. */
 	MSR_ARCH_PERFMON_PERFCTR0, MSR_ARCH_PERFMON_PERFCTR1,
 	MSR_ARCH_PERFMON_PERFCTR0 + 2, MSR_ARCH_PERFMON_PERFCTR0 + 3,
 	MSR_ARCH_PERFMON_PERFCTR0 + 4, MSR_ARCH_PERFMON_PERFCTR0 + 5,
@@ -1486,7 +1486,7 @@ static const u32 msrs_to_save_pmu[] = {
 	MSR_K7_EVNTSEL0, MSR_K7_EVNTSEL1, MSR_K7_EVNTSEL2, MSR_K7_EVNTSEL3,
 	MSR_K7_PERFCTR0, MSR_K7_PERFCTR1, MSR_K7_PERFCTR2, MSR_K7_PERFCTR3,
 
-	/* This part of MSRs should match KVM_AMD_PMC_MAX_GENERIC. */
+	/* This part of MSRs should match KVM_MAX_NR_AMD_GP_COUNTERS. */
 	MSR_F15H_PERF_CTL0, MSR_F15H_PERF_CTL1, MSR_F15H_PERF_CTL2,
 	MSR_F15H_PERF_CTL3, MSR_F15H_PERF_CTL4, MSR_F15H_PERF_CTL5,
 	MSR_F15H_PERF_CTR0, MSR_F15H_PERF_CTR1, MSR_F15H_PERF_CTR2,
@@ -7420,17 +7420,20 @@ static void kvm_probe_msr_to_save(u32 msr_index)
 		     intel_pt_validate_hw_cap(PT_CAP_num_address_ranges) * 2))
 			return;
 		break;
-	case MSR_ARCH_PERFMON_PERFCTR0 ... MSR_ARCH_PERFMON_PERFCTR_MAX:
+	case MSR_ARCH_PERFMON_PERFCTR0 ...
+	     MSR_ARCH_PERFMON_PERFCTR0 + KVM_MAX_NR_GP_COUNTERS - 1:
 		if (msr_index - MSR_ARCH_PERFMON_PERFCTR0 >=
 		    kvm_pmu_cap.num_counters_gp)
 			return;
 		break;
-	case MSR_ARCH_PERFMON_EVENTSEL0 ... MSR_ARCH_PERFMON_EVENTSEL_MAX:
+	case MSR_ARCH_PERFMON_EVENTSEL0 ...
+	     MSR_ARCH_PERFMON_EVENTSEL0 + KVM_MAX_NR_GP_COUNTERS - 1:
 		if (msr_index - MSR_ARCH_PERFMON_EVENTSEL0 >=
 		    kvm_pmu_cap.num_counters_gp)
 			return;
 		break;
-	case MSR_ARCH_PERFMON_FIXED_CTR0 ... MSR_ARCH_PERFMON_FIXED_CTR_MAX:
+	case MSR_ARCH_PERFMON_FIXED_CTR0 ...
+	     MSR_ARCH_PERFMON_FIXED_CTR0 + KVM_MAX_NR_FIXED_COUNTERS - 1:
 		if (msr_index - MSR_ARCH_PERFMON_FIXED_CTR0 >=
 		    kvm_pmu_cap.num_counters_fixed)
 			return;
@@ -7461,7 +7464,7 @@ static void kvm_init_msr_lists(void)
 {
 	unsigned i;
 
-	BUILD_BUG_ON_MSG(KVM_PMC_MAX_FIXED != 3,
+	BUILD_BUG_ON_MSG(KVM_MAX_NR_FIXED_COUNTERS != 3,
 			 "Please update the fixed PMCs in msrs_to_save_pmu[]");
 
 	num_msrs_to_save = 0;