KVM: x86: set TMR when the interrupt is accepted

Do not compute TMR in advance.  Instead, set the TMR just before the interrupt
is accepted into the IRR.  This limits the coupling between IOAPIC and LAPIC.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

5 files changed, 14 insertions, 23 deletions

diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
index 856f79105bb5..eaf4ec38d980 100644
--- a/arch/x86/kvm/ioapic.c
+++ b/arch/x86/kvm/ioapic.c
@@ -246,8 +246,7 @@ static void update_handled_vectors(struct kvm_ioapic *ioapic)
 	smp_wmb();
 }
 
-void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap,
-			u32 *tmr)
+void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
 {
 	struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
 	union kvm_ioapic_redirect_entry *e;
@@ -260,13 +259,9 @@ void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap,
 		    kvm_irq_has_notifier(ioapic->kvm, KVM_IRQCHIP_IOAPIC, index) ||
 		    index == RTC_GSI) {
 			if (kvm_apic_match_dest(vcpu, NULL, 0,
-				e->fields.dest_id, e->fields.dest_mode)) {
+				e->fields.dest_id, e->fields.dest_mode))
 				__set_bit(e->fields.vector,
 					(unsigned long *)eoi_exit_bitmap);
-				if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG)
-					__set_bit(e->fields.vector,
-						(unsigned long *)tmr);
-			}
 		}
 	}
 	spin_unlock(&ioapic->lock);
diff --git a/arch/x86/kvm/ioapic.h b/arch/x86/kvm/ioapic.h
index ca0b0b4e6256..3dbd0e2aac4e 100644
--- a/arch/x86/kvm/ioapic.h
+++ b/arch/x86/kvm/ioapic.h
@@ -120,7 +120,6 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
 		struct kvm_lapic_irq *irq, unsigned long *dest_map);
 int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
 int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
-void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap,
-			u32 *tmr);
+void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
 
 #endif
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 8d9013c5e1ee..5693dd9fc163 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -551,15 +551,6 @@ static void pv_eoi_clr_pending(struct kvm_vcpu *vcpu)
 	__clear_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention);
 }
 
-void kvm_apic_update_tmr(struct kvm_vcpu *vcpu, u32 *tmr)
-{
-	struct kvm_lapic *apic = vcpu->arch.apic;
-	int i;
-
-	for (i = 0; i < 8; i++)
-		apic_set_reg(apic, APIC_TMR + 0x10 * i, tmr[i]);
-}
-
 static void apic_update_ppr(struct kvm_lapic *apic)
 {
 	u32 tpr, isrv, ppr, old_ppr;
@@ -781,6 +772,9 @@ static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
 	case APIC_DM_LOWEST:
 		vcpu->arch.apic_arb_prio++;
 	case APIC_DM_FIXED:
+		if (unlikely(trig_mode && !level))
+			break;
+
 		/* FIXME add logic for vcpu on reset */
 		if (unlikely(!apic_enabled(apic)))
 			break;
@@ -790,6 +784,13 @@ static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
 		if (dest_map)
 			__set_bit(vcpu->vcpu_id, dest_map);
 
+		if (apic_test_vector(vector, apic->regs + APIC_TMR) != !!trig_mode) {
+			if (trig_mode)
+				apic_set_vector(vector, apic->regs + APIC_TMR);
+			else
+				apic_clear_vector(vector, apic->regs + APIC_TMR);
+		}
+
 		if (kvm_x86_ops->deliver_posted_interrupt)
 			kvm_x86_ops->deliver_posted_interrupt(vcpu, vector);
 		else {
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index 764037991d26..eb46d6bcaa75 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -57,7 +57,6 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value);
 u64 kvm_lapic_get_base(struct kvm_vcpu *vcpu);
 void kvm_apic_set_version(struct kvm_vcpu *vcpu);
 
-void kvm_apic_update_tmr(struct kvm_vcpu *vcpu, u32 *tmr);
 void __kvm_apic_update_irr(u32 *pir, void *regs);
 void kvm_apic_update_irr(struct kvm_vcpu *vcpu, u32 *pir);
 int kvm_apic_set_irq(struct kvm_vcpu *vcpu, struct kvm_lapic_irq *irq,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 92511d4b7236..c1ed74ebc502 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6144,17 +6144,14 @@ static void process_smi(struct kvm_vcpu *vcpu)
 static void vcpu_scan_ioapic(struct kvm_vcpu *vcpu)
 {
 	u64 eoi_exit_bitmap[4];
-	u32 tmr[8];
 
 	if (!kvm_apic_hw_enabled(vcpu->arch.apic))
 		return;
 
 	memset(eoi_exit_bitmap, 0, 32);
-	memset(tmr, 0, 32);
 
-	kvm_ioapic_scan_entry(vcpu, eoi_exit_bitmap, tmr);
+	kvm_ioapic_scan_entry(vcpu, eoi_exit_bitmap);
 	kvm_x86_ops->load_eoi_exitmap(vcpu, eoi_exit_bitmap);
-	kvm_apic_update_tmr(vcpu, tmr);
 }
 
 static void kvm_vcpu_flush_tlb(struct kvm_vcpu *vcpu)