Commit 41383771 authored by Gleb Natapov's avatar Gleb Natapov Committed by Avi Kivity
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KVM: Introduce bitmask for apic attention reasons 



The patch introduces a bitmap that will hold reasons apic should be
checked during vmexit. This is in a preparation for vp eoi patch
that will add one more check on vmexit. With the bitmap we can do
if(apic_attention) to check everything simultaneously which will
add zero overhead on the fast path.

Signed-off-by: default avatarGleb Natapov <gleb@redhat.com>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent 07975ad3

arch/x86/include/asm/kvm_host.h

+4 −0
Original line number Diff line number Diff line
@@ -172,6 +172,9 @@ enum { 
#define DR7_FIXED_1	0x00000400

#define DR7_VOLATILE	0xffff23ff



/* apic attention bits */

#define KVM_APIC_CHECK_VAPIC	0



/*

 * We don't want allocation failures within the mmu code, so we preallocate

 * enough memory for a single page fault in a cache.
@@ -337,6 +340,7 @@ struct kvm_vcpu_arch { 
	u64 efer;

	u64 apic_base;

	struct kvm_lapic *apic;    /* kernel irqchip context */

	unsigned long apic_attention;

	int32_t apic_arb_prio;

	int mp_state;

	int sipi_vector;

arch/x86/kvm/lapic.c

+7 −5
Original line number Diff line number Diff line
@@ -1088,6 +1088,7 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu) 
	apic_update_ppr(apic);



	vcpu->arch.apic_arb_prio = 0;

	vcpu->arch.apic_attention = 0;



	apic_debug(KERN_INFO "%s: vcpu=%p, id=%d, base_msr="

		   "0x%016" PRIx64 ", base_address=0x%0lx.\n", __func__,
@@ -1287,7 +1288,7 @@ void kvm_lapic_sync_from_vapic(struct kvm_vcpu *vcpu) 
	u32 data;

	void *vapic;



	if (!irqchip_in_kernel(vcpu->kvm) || !vcpu->arch.apic->vapic_addr)

	if (!test_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention))

		return;



	vapic = kmap_atomic(vcpu->arch.apic->vapic_page);
@@ -1304,7 +1305,7 @@ void kvm_lapic_sync_to_vapic(struct kvm_vcpu *vcpu) 
	struct kvm_lapic *apic;

	void *vapic;



	if (!irqchip_in_kernel(vcpu->kvm) || !vcpu->arch.apic->vapic_addr)

	if (!test_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention))

		return;



	apic = vcpu->arch.apic;
@@ -1324,10 +1325,11 @@ void kvm_lapic_sync_to_vapic(struct kvm_vcpu *vcpu) 


void kvm_lapic_set_vapic_addr(struct kvm_vcpu *vcpu, gpa_t vapic_addr)

{

	if (!irqchip_in_kernel(vcpu->kvm))

		return;



	vcpu->arch.apic->vapic_addr = vapic_addr;

	if (vapic_addr)

		__set_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention);

	else

		__clear_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention);

}



int kvm_x2apic_msr_write(struct kvm_vcpu *vcpu, u32 msr, u64 data)

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