#include <linux/kvm_host.h>
#include <linux/slab.h>
+#include <linux/workqueue.h>
#include "irq.h"
#include "i8254.h"
{
struct kvm_kpit_state *ps = container_of(kian, struct kvm_kpit_state,
irq_ack_notifier);
- raw_spin_lock(&ps->inject_lock);
- if (atomic_dec_return(&ps->pit_timer.pending) < 0)
+ int value;
+
+ spin_lock(&ps->inject_lock);
+ value = atomic_dec_return(&ps->pit_timer.pending);
+ if (value < 0)
+ /* spurious acks can be generated if, for example, the
+ * PIC is being reset. Handle it gracefully here
+ */
atomic_inc(&ps->pit_timer.pending);
+ else if (value > 0)
+ /* in this case, we had multiple outstanding pit interrupts
+ * that we needed to inject. Reinject
+ */
+ queue_work(ps->pit->wq, &ps->pit->expired);
ps->irq_ack = 1;
- raw_spin_unlock(&ps->inject_lock);
+ spin_unlock(&ps->inject_lock);
}
void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu)
hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
}
-static void destroy_pit_timer(struct kvm_timer *pt)
+static void destroy_pit_timer(struct kvm_pit *pit)
{
- pr_debug("execute del timer!\n");
- hrtimer_cancel(&pt->timer);
+ hrtimer_cancel(&pit->pit_state.pit_timer.timer);
+ cancel_work_sync(&pit->expired);
}
static bool kpit_is_periodic(struct kvm_timer *ktimer)
.is_periodic = kpit_is_periodic,
};
+static void pit_do_work(struct work_struct *work)
+{
+ struct kvm_pit *pit = container_of(work, struct kvm_pit, expired);
+ struct kvm *kvm = pit->kvm;
+ struct kvm_vcpu *vcpu;
+ int i;
+ struct kvm_kpit_state *ps = &pit->pit_state;
+ int inject = 0;
+
+ /* Try to inject pending interrupts when
+ * last one has been acked.
+ */
+ spin_lock(&ps->inject_lock);
+ if (ps->irq_ack) {
+ ps->irq_ack = 0;
+ inject = 1;
+ }
+ spin_unlock(&ps->inject_lock);
+ if (inject) {
+ kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 1);
+ kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 0);
+
+ /*
+ * Provides NMI watchdog support via Virtual Wire mode.
+ * The route is: PIT -> PIC -> LVT0 in NMI mode.
+ *
+ * Note: Our Virtual Wire implementation is simplified, only
+ * propagating PIT interrupts to all VCPUs when they have set
+ * LVT0 to NMI delivery. Other PIC interrupts are just sent to
+ * VCPU0, and only if its LVT0 is in EXTINT mode.
+ */
+ if (kvm->arch.vapics_in_nmi_mode > 0)
+ kvm_for_each_vcpu(i, vcpu, kvm)
+ kvm_apic_nmi_wd_deliver(vcpu);
+ }
+}
+
+static enum hrtimer_restart pit_timer_fn(struct hrtimer *data)
+{
+ struct kvm_timer *ktimer = container_of(data, struct kvm_timer, timer);
+ struct kvm_pit *pt = ktimer->kvm->arch.vpit;
+
+ if (ktimer->reinject || !atomic_read(&ktimer->pending)) {
+ atomic_inc(&ktimer->pending);
+ queue_work(pt->wq, &pt->expired);
+ }
+
+ if (ktimer->t_ops->is_periodic(ktimer)) {
+ hrtimer_add_expires_ns(&ktimer->timer, ktimer->period);
+ return HRTIMER_RESTART;
+ } else
+ return HRTIMER_NORESTART;
+}
+
static void create_pit_timer(struct kvm_kpit_state *ps, u32 val, int is_period)
{
struct kvm_timer *pt = &ps->pit_timer;
/* TODO The new value only affected after the retriggered */
hrtimer_cancel(&pt->timer);
+ cancel_work_sync(&ps->pit->expired);
pt->period = interval;
ps->is_periodic = is_period;
- pt->timer.function = kvm_timer_fn;
+ pt->timer.function = pit_timer_fn;
pt->t_ops = &kpit_ops;
pt->kvm = ps->pit->kvm;
- pt->vcpu = pt->kvm->bsp_vcpu;
atomic_set(&pt->pending, 0);
ps->irq_ack = 1;
}
break;
default:
- destroy_pit_timer(&ps->pit_timer);
+ destroy_pit_timer(kvm->arch.vpit);
}
}
mutex_init(&pit->pit_state.lock);
mutex_lock(&pit->pit_state.lock);
- raw_spin_lock_init(&pit->pit_state.inject_lock);
+ spin_lock_init(&pit->pit_state.inject_lock);
+
+ pit->wq = create_singlethread_workqueue("kvm-pit-wq");
+ if (!pit->wq) {
+ kfree(pit);
+ return NULL;
+ }
+ INIT_WORK(&pit->expired, pit_do_work);
kvm->arch.vpit = pit;
pit->kvm = kvm;
mutex_lock(&kvm->arch.vpit->pit_state.lock);
timer = &kvm->arch.vpit->pit_state.pit_timer.timer;
hrtimer_cancel(timer);
+ cancel_work_sync(&kvm->arch.vpit->expired);
kvm_free_irq_source_id(kvm, kvm->arch.vpit->irq_source_id);
mutex_unlock(&kvm->arch.vpit->pit_state.lock);
+ destroy_workqueue(kvm->arch.vpit->wq);
kfree(kvm->arch.vpit);
}
}
-
-static void __inject_pit_timer_intr(struct kvm *kvm)
-{
- struct kvm_vcpu *vcpu;
- int i;
-
- kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 1);
- kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 0);
-
- /*
- * Provides NMI watchdog support via Virtual Wire mode.
- * The route is: PIT -> PIC -> LVT0 in NMI mode.
- *
- * Note: Our Virtual Wire implementation is simplified, only
- * propagating PIT interrupts to all VCPUs when they have set
- * LVT0 to NMI delivery. Other PIC interrupts are just sent to
- * VCPU0, and only if its LVT0 is in EXTINT mode.
- */
- if (kvm->arch.vapics_in_nmi_mode > 0)
- kvm_for_each_vcpu(i, vcpu, kvm)
- kvm_apic_nmi_wd_deliver(vcpu);
-}
-
-void kvm_inject_pit_timer_irqs(struct kvm_vcpu *vcpu)
-{
- struct kvm_pit *pit = vcpu->kvm->arch.vpit;
- struct kvm *kvm = vcpu->kvm;
- struct kvm_kpit_state *ps;
-
- if (pit) {
- int inject = 0;
- ps = &pit->pit_state;
-
- /* Try to inject pending interrupts when
- * last one has been acked.
- */
- raw_spin_lock(&ps->inject_lock);
- if (atomic_read(&ps->pit_timer.pending) && ps->irq_ack) {
- ps->irq_ack = 0;
- inject = 1;
- }
- raw_spin_unlock(&ps->inject_lock);
- if (inject)
- __inject_pit_timer_intr(kvm);
- }
-}
git.openpandora.org / pandora-kernel.git / blobdiff