KVM: Migrate lapic hrtimer when vcpu moves to another cpu
This reduces overhead by accessing cachelines from the wrong node, as well
as simplifying locking.
[Qing: fix for inactive or expired one-shot timer]
Signed-off-by: Yaozu (Eddie) Dong <Eddie.Dong@intel.com>
Signed-off-by: Qing He <qing.he@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/drivers/kvm/lapic.c b/drivers/kvm/lapic.c
index 490d493..2706ec3 100644
--- a/drivers/kvm/lapic.c
+++ b/drivers/kvm/lapic.c
@@ -979,3 +979,17 @@
update_divide_count(apic);
start_apic_timer(apic);
}
+
+void kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
+{
+ struct kvm_lapic *apic = vcpu->apic;
+ struct hrtimer *timer;
+
+ if (!apic)
+ return;
+
+ timer = &apic->timer.dev;
+ if (hrtimer_cancel(timer))
+ hrtimer_start(timer, timer->expires, HRTIMER_MODE_ABS);
+}
+EXPORT_SYMBOL_GPL(kvm_migrate_apic_timer);