KVM: x86: Track supported PERF_CAPABILITIES in kvm_caps

Track KVM's supported PERF_CAPABILITIES in kvm_caps instead of computing
the supported capabilities on the fly every time.  Using kvm_caps will
also allow for future cleanups as the kvm_caps values can be used
directly in common x86 code.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Acked-by: Like Xu <likexu@tencent.com>
Message-Id: <20221006000314.73240-6-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 9f88c8e..d15f193 100644 (file)
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -2714,6 +2714,7 @@ static int svm_get_msr_feature(struct kvm_msr_entry *msr)
                        msr->data |= MSR_F10H_DECFG_LFENCE_SERIALIZE;
                break;
        case MSR_IA32_PERF_CAPABILITIES:
+               msr->data = kvm_caps.supported_perf_cap;
                return 0;
        default:
                return KVM_MSR_RET_INVALID;
@@ -4865,6 +4866,7 @@ static __init void svm_set_cpu_caps(void)
 {
        kvm_set_cpu_caps();
 
+       kvm_caps.supported_perf_cap = 0;
        kvm_caps.supported_xss = 0;
 
        /* CPUID 0x80000001 and 0x8000000A (SVM features) */

diff --git a/arch/x86/kvm/vmx/capabilities.h b/arch/x86/kvm/vmx/capabilities.h
index 479124e..cd2ac95 100644 (file)
--- a/arch/x86/kvm/vmx/capabilities.h
+++ b/arch/x86/kvm/vmx/capabilities.h
@@ -395,31 +395,6 @@ static inline bool vmx_pebs_supported(void)
        return boot_cpu_has(X86_FEATURE_PEBS) && kvm_pmu_cap.pebs_ept;
 }
 
-static inline u64 vmx_get_perf_capabilities(void)
-{
-       u64 perf_cap = PMU_CAP_FW_WRITES;
-       struct x86_pmu_lbr lbr;
-       u64 host_perf_cap = 0;
-
-       if (!enable_pmu)
-               return 0;
-
-       if (boot_cpu_has(X86_FEATURE_PDCM))
-               rdmsrl(MSR_IA32_PERF_CAPABILITIES, host_perf_cap);
-
-       x86_perf_get_lbr(&lbr);
-       if (lbr.nr)
-               perf_cap |= host_perf_cap & PMU_CAP_LBR_FMT;
-
-       if (vmx_pebs_supported()) {
-               perf_cap |= host_perf_cap & PERF_CAP_PEBS_MASK;
-               if ((perf_cap & PERF_CAP_PEBS_FORMAT) < 4)
-                       perf_cap &= ~PERF_CAP_PEBS_BASELINE;
-       }
-
-       return perf_cap;
-}
-
 static inline bool cpu_has_notify_vmexit(void)
 {
        return vmcs_config.cpu_based_2nd_exec_ctrl &

diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index 10b33da..9fabfe7 100644 (file)
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -631,7 +631,7 @@ static void intel_pmu_init(struct kvm_vcpu *vcpu)
                pmu->fixed_counters[i].current_config = 0;
        }
 
-       vcpu->arch.perf_capabilities = vmx_get_perf_capabilities();
+       vcpu->arch.perf_capabilities = kvm_caps.supported_perf_cap;
        lbr_desc->records.nr = 0;
        lbr_desc->event = NULL;
        lbr_desc->msr_passthrough = false;

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 63247c5..3fec439 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -1850,7 +1850,7 @@ static int vmx_get_msr_feature(struct kvm_msr_entry *msr)
                        return 1;
                return vmx_get_vmx_msr(&vmcs_config.nested, msr->index, &msr->data);
        case MSR_IA32_PERF_CAPABILITIES:
-               msr->data = vmx_get_perf_capabilities();
+               msr->data = kvm_caps.supported_perf_cap;
                return 0;
        default:
                return KVM_MSR_RET_INVALID;
@@ -2029,7 +2029,7 @@ static u64 vmx_get_supported_debugctl(struct kvm_vcpu *vcpu, bool host_initiated
            (host_initiated || guest_cpuid_has(vcpu, X86_FEATURE_BUS_LOCK_DETECT)))
                debugctl |= DEBUGCTLMSR_BUS_LOCK_DETECT;
 
-       if ((vmx_get_perf_capabilities() & PMU_CAP_LBR_FMT) &&
+       if ((kvm_caps.supported_perf_cap & PMU_CAP_LBR_FMT) &&
            (host_initiated || intel_pmu_lbr_is_enabled(vcpu)))
                debugctl |= DEBUGCTLMSR_LBR | DEBUGCTLMSR_FREEZE_LBRS_ON_PMI;
 
@@ -2342,14 +2342,14 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
                        return 1;
                if (data & PMU_CAP_LBR_FMT) {
                        if ((data & PMU_CAP_LBR_FMT) !=
-                           (vmx_get_perf_capabilities() & PMU_CAP_LBR_FMT))
+                           (kvm_caps.supported_perf_cap & PMU_CAP_LBR_FMT))
                                return 1;
                        if (!cpuid_model_is_consistent(vcpu))
                                return 1;
                }
                if (data & PERF_CAP_PEBS_FORMAT) {
                        if ((data & PERF_CAP_PEBS_MASK) !=
-                           (vmx_get_perf_capabilities() & PERF_CAP_PEBS_MASK))
+                           (kvm_caps.supported_perf_cap & PERF_CAP_PEBS_MASK))
                                return 1;
                        if (!guest_cpuid_has(vcpu, X86_FEATURE_DS))
                                return 1;
@@ -7669,6 +7669,31 @@ static void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
        vmx_update_exception_bitmap(vcpu);
 }
 
+static u64 vmx_get_perf_capabilities(void)
+{
+       u64 perf_cap = PMU_CAP_FW_WRITES;
+       struct x86_pmu_lbr lbr;
+       u64 host_perf_cap = 0;
+
+       if (!enable_pmu)
+               return 0;
+
+       if (boot_cpu_has(X86_FEATURE_PDCM))
+               rdmsrl(MSR_IA32_PERF_CAPABILITIES, host_perf_cap);
+
+       x86_perf_get_lbr(&lbr);
+       if (lbr.nr)
+               perf_cap |= host_perf_cap & PMU_CAP_LBR_FMT;
+
+       if (vmx_pebs_supported()) {
+               perf_cap |= host_perf_cap & PERF_CAP_PEBS_MASK;
+               if ((perf_cap & PERF_CAP_PEBS_FORMAT) < 4)
+                       perf_cap &= ~PERF_CAP_PEBS_BASELINE;
+       }
+
+       return perf_cap;
+}
+
 static __init void vmx_set_cpu_caps(void)
 {
        kvm_set_cpu_caps();
@@ -7691,6 +7716,7 @@ static __init void vmx_set_cpu_caps(void)
 
        if (!enable_pmu)
                kvm_cpu_cap_clear(X86_FEATURE_PDCM);
+       kvm_caps.supported_perf_cap = vmx_get_perf_capabilities();
 
        if (!enable_sgx) {
                kvm_cpu_cap_clear(X86_FEATURE_SGX);

diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 829d313..9de7258 100644 (file)
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -27,6 +27,7 @@ struct kvm_caps {
        u64 supported_mce_cap;
        u64 supported_xcr0;
        u64 supported_xss;
+       u64 supported_perf_cap;
 };
 
 void kvm_spurious_fault(void);