Commit ca0245d1 authored by Chao Gao's avatar Chao Gao Committed by Sean Christopherson
Browse files

KVM: x86: Remove hwapic_irr_update() from kvm_x86_ops 



Remove the redundant .hwapic_irr_update() ops.

If a vCPU has APICv enabled, KVM updates its RVI before VM-enter to L1
in vmx_sync_pir_to_irr(). This guarantees RVI is up-to-date and aligned
with the vIRR in the virtual APIC. So, no need to update RVI every time
the vIRR changes.

Note that KVM never updates vmcs02 RVI in .hwapic_irr_update() or
vmx_sync_pir_to_irr(). So, removing .hwapic_irr_update() has no
impact to the nested case.

Signed-off-by: default avatarChao Gao <chao.gao@intel.com>
Link: https://lore.kernel.org/r/20241111085947.432645-1-chao.gao@intel.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 3d91521e

arch/x86/include/asm/kvm-x86-ops.h

+0 −1
Original line number Diff line number Diff line
@@ -83,7 +83,6 @@ KVM_X86_OP(enable_nmi_window) 
KVM_X86_OP(enable_irq_window)

KVM_X86_OP_OPTIONAL(update_cr8_intercept)

KVM_X86_OP(refresh_apicv_exec_ctrl)

KVM_X86_OP_OPTIONAL(hwapic_irr_update)

KVM_X86_OP_OPTIONAL(hwapic_isr_update)

KVM_X86_OP_OPTIONAL(load_eoi_exitmap)

KVM_X86_OP_OPTIONAL(set_virtual_apic_mode)

arch/x86/include/asm/kvm_host.h

+0 −1
Original line number Diff line number Diff line
@@ -1734,7 +1734,6 @@ struct kvm_x86_ops { 
	const unsigned long required_apicv_inhibits;

	bool allow_apicv_in_x2apic_without_x2apic_virtualization;

	void (*refresh_apicv_exec_ctrl)(struct kvm_vcpu *vcpu);

	void (*hwapic_irr_update)(struct kvm_vcpu *vcpu, int max_irr);

	void (*hwapic_isr_update)(struct kvm_vcpu *vcpu, int isr);

	void (*load_eoi_exitmap)(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);

	void (*set_virtual_apic_mode)(struct kvm_vcpu *vcpu);

arch/x86/kvm/lapic.c

+0 −5
Original line number Diff line number Diff line
@@ -734,10 +734,7 @@ static inline int apic_find_highest_irr(struct kvm_lapic *apic) 
static inline void apic_clear_irr(int vec, struct kvm_lapic *apic)

{

	if (unlikely(apic->apicv_active)) {

		/* need to update RVI */

		kvm_lapic_clear_vector(vec, apic->regs + APIC_IRR);

		kvm_x86_call(hwapic_irr_update)(apic->vcpu,

						apic_find_highest_irr(apic));

	} else {

		apic->irr_pending = false;

		kvm_lapic_clear_vector(vec, apic->regs + APIC_IRR);
@@ -2816,7 +2813,6 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event) 
	apic_update_ppr(apic);

	if (apic->apicv_active) {

		kvm_x86_call(apicv_post_state_restore)(vcpu);

		kvm_x86_call(hwapic_irr_update)(vcpu, -1);

		kvm_x86_call(hwapic_isr_update)(vcpu, -1);

	}
@@ -3132,7 +3128,6 @@ int kvm_apic_set_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s) 
	kvm_apic_update_apicv(vcpu);

	if (apic->apicv_active) {

		kvm_x86_call(apicv_post_state_restore)(vcpu);

		kvm_x86_call(hwapic_irr_update)(vcpu, apic_find_highest_irr(apic));

		kvm_x86_call(hwapic_isr_update)(vcpu, apic_find_highest_isr(apic));

	}

	kvm_make_request(KVM_REQ_EVENT, vcpu);

arch/x86/kvm/vmx/main.c

+0 −1
Original line number Diff line number Diff line
@@ -100,7 +100,6 @@ struct kvm_x86_ops vt_x86_ops __initdata = { 
	.load_eoi_exitmap = vmx_load_eoi_exitmap,

	.apicv_pre_state_restore = vmx_apicv_pre_state_restore,

	.required_apicv_inhibits = VMX_REQUIRED_APICV_INHIBITS,

	.hwapic_irr_update = vmx_hwapic_irr_update,

	.hwapic_isr_update = vmx_hwapic_isr_update,

	.sync_pir_to_irr = vmx_sync_pir_to_irr,

	.deliver_interrupt = vmx_deliver_interrupt,

arch/x86/kvm/vmx/vmx.c

+0 −14
Original line number Diff line number Diff line
@@ -6918,20 +6918,6 @@ static void vmx_set_rvi(int vector) 
	}

}



void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr)

{

	/*

	 * When running L2, updating RVI is only relevant when

	 * vmcs12 virtual-interrupt-delivery enabled.

	 * However, it can be enabled only when L1 also

	 * intercepts external-interrupts and in that case

	 * we should not update vmcs02 RVI but instead intercept

	 * interrupt. Therefore, do nothing when running L2.

	 */

	if (!is_guest_mode(vcpu))

		vmx_set_rvi(max_irr);

}



int vmx_sync_pir_to_irr(struct kvm_vcpu *vcpu)

{

	struct vcpu_vmx *vmx = to_vmx(vcpu);