commit 2f5997140f22f68f6390c49941150d3fa8a95cb7
author Marcelo Tosatti <mtosatti@redhat.com> Tue May 27 12:10:20 2008 -0300
committer Avi Kivity <avi@qumranet.com> Fri Jun 06 21:25:51 2008 +0300
tree 790370cfb5ea5cd16a892c3a8b2bb75a2f30b489
parent 9dcb40e1aa5bfe7d6ffc729f3c2b6c8f1392d2d3

KVM: migrate PIT timer

Migrate the PIT timer to the physical CPU which vcpu0 is scheduled on,
similarly to what is done for the LAPIC timers, otherwise PIT interrupts
will be delayed until an unrelated event causes an exit.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

arch/x86/kvm/i8254.c

diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index 7c077a9..f2f5d26 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -200,7 +200,6 @@
 
 	atomic_inc(&pt->pending);
 	smp_mb__after_atomic_inc();
-	/* FIXME: handle case where the guest is in guest mode */
 	if (vcpu0 && waitqueue_active(&vcpu0->wq)) {
 		vcpu0->arch.mp_state = KVM_MP_STATE_RUNNABLE;
 		wake_up_interruptible(&vcpu0->wq);
@@ -237,6 +236,19 @@
 		return HRTIMER_NORESTART;
 }
 
+void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu)
+{
+	struct kvm_pit *pit = vcpu->kvm->arch.vpit;
+	struct hrtimer *timer;
+
+	if (vcpu->vcpu_id != 0 || !pit)
+		return;
+
+	timer = &pit->pit_state.pit_timer.timer;
+	if (hrtimer_cancel(timer))
+		hrtimer_start(timer, timer->expires, HRTIMER_MODE_ABS);
+}
+
 static void destroy_pit_timer(struct kvm_kpit_timer *pt)
 {
 	pr_debug("pit: execute del timer!\n");

arch/x86/kvm/irq.c

diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index ce1f583..76d736b 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -94,3 +94,9 @@
 	/* TODO: PIT, RTC etc. */
 }
 EXPORT_SYMBOL_GPL(kvm_timer_intr_post);
+
+void __kvm_migrate_timers(struct kvm_vcpu *vcpu)
+{
+	__kvm_migrate_apic_timer(vcpu);
+	__kvm_migrate_pit_timer(vcpu);
+}

arch/x86/kvm/irq.h

diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
index 1802134..2a15be2 100644
--- a/arch/x86/kvm/irq.h
+++ b/arch/x86/kvm/irq.h
@@ -84,6 +84,8 @@
 void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu);
 void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu);
 void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu);
+void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu);
+void __kvm_migrate_timers(struct kvm_vcpu *vcpu);
 
 int pit_has_pending_timer(struct kvm_vcpu *vcpu);
 int apic_has_pending_timer(struct kvm_vcpu *vcpu);

arch/x86/kvm/svm.c

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index ab22615..6b0d5fa 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -688,7 +688,7 @@
 		delta = vcpu->arch.host_tsc - tsc_this;
 		svm->vmcb->control.tsc_offset += delta;
 		vcpu->cpu = cpu;
-		kvm_migrate_apic_timer(vcpu);
+		kvm_migrate_timers(vcpu);
 	}
 
 	for (i = 0; i < NR_HOST_SAVE_USER_MSRS; i++)

arch/x86/kvm/vmx.c

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index bfe4db1..96445f3 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -608,7 +608,7 @@
 
 	if (vcpu->cpu != cpu) {
 		vcpu_clear(vmx);
-		kvm_migrate_apic_timer(vcpu);
+		kvm_migrate_timers(vcpu);
 		vpid_sync_vcpu_all(vmx);
 	}
 

arch/x86/kvm/x86.c

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 21338bd..00acf13 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2758,7 +2758,7 @@
 
 	if (vcpu->requests) {
 		if (test_and_clear_bit(KVM_REQ_MIGRATE_TIMER, &vcpu->requests))
-			__kvm_migrate_apic_timer(vcpu);
+			__kvm_migrate_timers(vcpu);
 		if (test_and_clear_bit(KVM_REQ_REPORT_TPR_ACCESS,
 				       &vcpu->requests)) {
 			kvm_run->exit_reason = KVM_EXIT_TPR_ACCESS;