Wanpeng Li <[email protected]> writes: > From: Wanpeng Li <[email protected]> > > We can't observe benefit from single target IPI fastpath when APICv is > disabled, let's just enable IPI and Timer fastpath when APICv is enabled > for now. > > Tested-by: Haiwei Li <[email protected]> > Cc: Haiwei Li <[email protected]> > Signed-off-by: Wanpeng Li <[email protected]> > --- > arch/x86/kvm/svm/svm.c | 2 +- > arch/x86/kvm/vmx/vmx.c | 2 +- > 2 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c > index 8f8fc65..1e7220e 100644 > --- a/arch/x86/kvm/svm/svm.c > +++ b/arch/x86/kvm/svm/svm.c > @@ -3344,7 +3344,7 @@ static void svm_cancel_injection(struct kvm_vcpu *vcpu) > > static enum exit_fastpath_completion svm_exit_handlers_fastpath(struct > kvm_vcpu *vcpu) > { > - if (!is_guest_mode(vcpu) && > + if (!is_guest_mode(vcpu) && vcpu->arch.apicv_active && > to_svm(vcpu)->vmcb->control.exit_code == SVM_EXIT_MSR && > to_svm(vcpu)->vmcb->control.exit_info_1) > return handle_fastpath_set_msr_irqoff(vcpu); > diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c > index 9b5adb4..f207004 100644 > --- a/arch/x86/kvm/vmx/vmx.c > +++ b/arch/x86/kvm/vmx/vmx.c > @@ -6585,7 +6585,7 @@ void vmx_update_host_rsp(struct vcpu_vmx *vmx, unsigned > long host_rsp) > > static enum exit_fastpath_completion vmx_exit_handlers_fastpath(struct > kvm_vcpu *vcpu) > { > - if (!is_guest_mode(vcpu)) { > + if (!is_guest_mode(vcpu) && vcpu->arch.apicv_active) { > switch (to_vmx(vcpu)->exit_reason) { > case EXIT_REASON_MSR_WRITE: > return handle_fastpath_set_msr_irqoff(vcpu);
I think that apicv_active checks are specific to APIC MSRs but handle_fastpath_set_msr_irqoff() can handle any other MSR as well. I'd suggest to move the check inside handle_fastpath_set_msr_irqoff(). Also, enabling Hyper-V SynIC leads to disabling apicv. It it still pointless to keep fastpath enabled? -- Vitaly
