From b4eef9b36db461ca44832226fbca614db58c0c33 Mon Sep 17 00:00:00 2001 From: Tiejun Chen Date: Mon, 22 Dec 2014 10:32:57 +0100 Subject: [PATCH] kvm: x86: vmx: NULL out hwapic_isr_update() in case of !enable_apicv In most cases calling hwapic_isr_update(), we always check if kvm_apic_vid_enabled() == 1, but actually, kvm_apic_vid_enabled() -> kvm_x86_ops->vm_has_apicv() -> vmx_vm_has_apicv() or '0' in svm case -> return enable_apicv && irqchip_in_kernel(kvm) So its a little cost to recall vmx_vm_has_apicv() inside hwapic_isr_update(), here just NULL out hwapic_isr_update() in case of !enable_apicv inside hardware_setup() then make all related stuffs follow this. Note we don't check this under that condition of irqchip_in_kernel() since we should make sure definitely any caller don't work without in-kernel irqchip. Signed-off-by: Tiejun Chen Signed-off-by: Paolo Bonzini --- arch/x86/kvm/lapic.c | 8 +++++--- arch/x86/kvm/vmx.c | 4 +--- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 4f0c0b954686..fe8bae511e99 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -402,7 +402,7 @@ static inline void apic_set_isr(int vec, struct kvm_lapic *apic) * because the processor can modify ISR under the hood. Instead * just set SVI. */ - if (unlikely(kvm_apic_vid_enabled(vcpu->kvm))) + if (unlikely(kvm_x86_ops->hwapic_isr_update)) kvm_x86_ops->hwapic_isr_update(vcpu->kvm, vec); else { ++apic->isr_count; @@ -450,7 +450,7 @@ static inline void apic_clear_isr(int vec, struct kvm_lapic *apic) * on the other hand isr_count and highest_isr_cache are unused * and must be left alone. */ - if (unlikely(kvm_apic_vid_enabled(vcpu->kvm))) + if (unlikely(kvm_x86_ops->hwapic_isr_update)) kvm_x86_ops->hwapic_isr_update(vcpu->kvm, apic_find_highest_isr(apic)); else { @@ -1742,7 +1742,9 @@ void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu, if (kvm_x86_ops->hwapic_irr_update) kvm_x86_ops->hwapic_irr_update(vcpu, apic_find_highest_irr(apic)); - kvm_x86_ops->hwapic_isr_update(vcpu->kvm, apic_find_highest_isr(apic)); + if (unlikely(kvm_x86_ops->hwapic_isr_update)) + kvm_x86_ops->hwapic_isr_update(vcpu->kvm, + apic_find_highest_isr(apic)); kvm_make_request(KVM_REQ_EVENT, vcpu); kvm_rtc_eoi_tracking_restore_one(vcpu); } diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index e14c96e574ff..6e71fac27d4e 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -5895,6 +5895,7 @@ static __init int hardware_setup(void) kvm_x86_ops->update_cr8_intercept = NULL; else { kvm_x86_ops->hwapic_irr_update = NULL; + kvm_x86_ops->hwapic_isr_update = NULL; kvm_x86_ops->deliver_posted_interrupt = NULL; kvm_x86_ops->sync_pir_to_irr = vmx_sync_pir_to_irr_dummy; } @@ -7478,9 +7479,6 @@ static void vmx_hwapic_isr_update(struct kvm *kvm, int isr) u16 status; u8 old; - if (!vmx_vm_has_apicv(kvm)) - return; - if (isr == -1) isr = 0;