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Diffstat (limited to 'arch/x86/kvm/lapic.c')
-rw-r--r--arch/x86/kvm/lapic.c38
1 files changed, 24 insertions, 14 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index bd13fdddbdc4..4924f83ed4f3 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1454,7 +1454,7 @@ static void apic_timer_expired(struct kvm_lapic *apic)
if (swait_active(q))
swake_up_one(q);
- if (apic_lvtt_tscdeadline(apic))
+ if (apic_lvtt_tscdeadline(apic) || ktimer->hv_timer_in_use)
ktimer->expired_tscdeadline = ktimer->tscdeadline;
}
@@ -1696,37 +1696,42 @@ static void cancel_hv_timer(struct kvm_lapic *apic)
static bool start_hv_timer(struct kvm_lapic *apic)
{
struct kvm_timer *ktimer = &apic->lapic_timer;
- int r;
+ struct kvm_vcpu *vcpu = apic->vcpu;
+ bool expired;
WARN_ON(preemptible());
if (!kvm_x86_ops->set_hv_timer)
return false;
- if (!apic_lvtt_period(apic) && atomic_read(&ktimer->pending))
- return false;
-
if (!ktimer->tscdeadline)
return false;
- r = kvm_x86_ops->set_hv_timer(apic->vcpu, ktimer->tscdeadline);
- if (r < 0)
+ if (kvm_x86_ops->set_hv_timer(vcpu, ktimer->tscdeadline, &expired))
return false;
ktimer->hv_timer_in_use = true;
hrtimer_cancel(&ktimer->timer);
/*
- * Also recheck ktimer->pending, in case the sw timer triggered in
- * the window. For periodic timer, leave the hv timer running for
- * simplicity, and the deadline will be recomputed on the next vmexit.
+ * To simplify handling the periodic timer, leave the hv timer running
+ * even if the deadline timer has expired, i.e. rely on the resulting
+ * VM-Exit to recompute the periodic timer's target expiration.
*/
- if (!apic_lvtt_period(apic) && (r || atomic_read(&ktimer->pending))) {
- if (r)
+ if (!apic_lvtt_period(apic)) {
+ /*
+ * Cancel the hv timer if the sw timer fired while the hv timer
+ * was being programmed, or if the hv timer itself expired.
+ */
+ if (atomic_read(&ktimer->pending)) {
+ cancel_hv_timer(apic);
+ } else if (expired) {
apic_timer_expired(apic);
- return false;
+ cancel_hv_timer(apic);
+ }
}
- trace_kvm_hv_timer_state(apic->vcpu->vcpu_id, true);
+ trace_kvm_hv_timer_state(vcpu->vcpu_id, ktimer->hv_timer_in_use);
+
return true;
}
@@ -1750,8 +1755,13 @@ static void start_sw_timer(struct kvm_lapic *apic)
static void restart_apic_timer(struct kvm_lapic *apic)
{
preempt_disable();
+
+ if (!apic_lvtt_period(apic) && atomic_read(&apic->lapic_timer.pending))
+ goto out;
+
if (!start_hv_timer(apic))
start_sw_timer(apic);
+out:
preempt_enable();
}