diff options
| author | Sean Christopherson <sean.j.christopherson@intel.com> | 2019-09-05 14:22:55 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2019-09-10 19:18:29 +0200 |
| commit | 1edce0a9eb239b7a2768d10cf7d21dd83e269d5b (patch) | |
| tree | bd0f6dafd4ea0904a810717fe7577caec8dcd1a7 /arch/x86/include/asm | |
| parent | f20935d85a23c33f5361661747ffa975549f56d5 (diff) | |
KVM: x86: Add kvm_emulate_{rd,wr}msr() to consolidate VXM/SVM code
Move RDMSR and WRMSR emulation into common x86 code to consolidate
nearly identical SVM and VMX code.
Note, consolidating RDMSR introduces an extra indirect call, i.e.
retpoline, due to reaching {svm,vmx}_get_msr() via kvm_x86_ops, but a
guest kernel likely has bigger problems if increasing the latency of
RDMSR VM-Exits by ~70 cycles has a measurable impact on overall VM
performance. E.g. the only recurring RDMSR VM-Exits (after booting) on
my system running Linux 5.2 in the guest are for MSR_IA32_TSC_ADJUST via
arch_cpu_idle_enter().
No functional change intended.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/include/asm')
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 059c29cb0714..c4f271a9b306 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1328,6 +1328,8 @@ void kvm_enable_efer_bits(u64); bool kvm_valid_efer(struct kvm_vcpu *vcpu, u64 efer); int kvm_get_msr(struct kvm_vcpu *vcpu, u32 index, u64 *data); int kvm_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data); +int kvm_emulate_rdmsr(struct kvm_vcpu *vcpu); +int kvm_emulate_wrmsr(struct kvm_vcpu *vcpu); struct x86_emulate_ctxt; |