diff options
| author | Sean Christopherson <seanjc@google.com> | 2022-07-27 23:34:24 +0000 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-08-10 15:08:30 -0400 |
| commit | 6348aafa8d24c156124f76b5a1507079c3213112 (patch) | |
| tree | a917665371c90aaacd68fa3622398c5d7456d8ea /arch/x86/kvm/vmx/vmx.h | |
| parent | 7de8e5b6b139a3a94aca24e8d8d35b77dc33e0ac (diff) | |
KVM: VMX: Adjust number of LBR records for PERF_CAPABILITIES at refresh
Now that the PMU is refreshed when MSR_IA32_PERF_CAPABILITIES is written
by host userspace, zero out the number of LBR records for a vCPU during
PMU refresh if PMU_CAP_LBR_FMT is not set in PERF_CAPABILITIES instead of
handling the check at run-time.
guest_cpuid_has() is expensive due to the linear search of guest CPUID
entries, intel_pmu_lbr_is_enabled() is checked on every VM-Enter, _and_
simply enumerating the same "Model" as the host causes KVM to set the
number of LBR records to a non-zero value.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220727233424.2968356-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/vmx/vmx.h')
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.h | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h index f57a527cc589..24d58c2ffaa3 100644 --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -544,9 +544,12 @@ static inline struct x86_pmu_lbr *vcpu_to_lbr_records(struct kvm_vcpu *vcpu) return &vcpu_to_lbr_desc(vcpu)->records; } -void intel_pmu_cross_mapped_check(struct kvm_pmu *pmu); -bool intel_pmu_lbr_is_enabled(struct kvm_vcpu *vcpu); +static inline bool intel_pmu_lbr_is_enabled(struct kvm_vcpu *vcpu) +{ + return !!vcpu_to_lbr_records(vcpu)->nr; +} +void intel_pmu_cross_mapped_check(struct kvm_pmu *pmu); int intel_pmu_create_guest_lbr_event(struct kvm_vcpu *vcpu); void vmx_passthrough_lbr_msrs(struct kvm_vcpu *vcpu); |