arch/x86/kvm/timer.c

   1 #include <linux/kvm_host.h>
   2 #include <linux/kvm.h>
   3 #include <linux/hrtimer.h>
   4 #include <asm/atomic.h>
   5 #include "kvm_timer.h"
   6
   7 static int __kvm_timer_fn(struct kvm_vcpu *vcpu, struct kvm_timer *ktimer)
   8 {
   9         int restart_timer = 0;
  10         wait_queue_head_t *q = &vcpu->wq;
  11
  12         /* FIXME: this code should not know anything about vcpus */
  13         if (!atomic_inc_and_test(&ktimer->pending))
  14                 set_bit(KVM_REQ_PENDING_TIMER, &vcpu->requests);
  15
  16         if (!ktimer->reinject)
  17                 atomic_set(&ktimer->pending, 1);
  18
  19         if (waitqueue_active(q))
  20                 wake_up_interruptible(q);
  21
  22         if (ktimer->t_ops->is_periodic(ktimer)) {
  23                 hrtimer_add_expires_ns(&ktimer->timer, ktimer->period);
  24                 restart_timer = 1;
  25         }
  26
  27         return restart_timer;
  28 }
  29
  30 enum hrtimer_restart kvm_timer_fn(struct hrtimer *data)
  31 {
  32         int restart_timer;
  33         struct kvm_vcpu *vcpu;
  34         struct kvm_timer *ktimer = container_of(data, struct kvm_timer, timer);
  35
  36         vcpu = ktimer->kvm->vcpus[ktimer->vcpu_id];
  37         if (!vcpu)
  38                 return HRTIMER_NORESTART;
  39
  40         restart_timer = __kvm_timer_fn(vcpu, ktimer);
  41         if (restart_timer)
  42                 return HRTIMER_RESTART;
  43         else
  44                 return HRTIMER_NORESTART;
  45 }
  46