KVM: unify part of generic timer handling
[safe/jmp/linux-2.6] / 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