mirror of
https://github.com/torvalds/linux.git
synced 2024-12-30 14:52:05 +00:00
66 lines
1.6 KiB
C
66 lines
1.6 KiB
C
/*
|
|
* Kernel-based Virtual Machine driver for Linux
|
|
*
|
|
* This module enables machines with Intel VT-x extensions to run virtual
|
|
* machines without emulation or binary translation.
|
|
*
|
|
* timer support
|
|
*
|
|
* Copyright 2010 Red Hat, Inc. and/or its affilates.
|
|
*
|
|
* This work is licensed under the terms of the GNU GPL, version 2. See
|
|
* the COPYING file in the top-level directory.
|
|
*/
|
|
|
|
#include <linux/kvm_host.h>
|
|
#include <linux/kvm.h>
|
|
#include <linux/hrtimer.h>
|
|
#include <asm/atomic.h>
|
|
#include "kvm_timer.h"
|
|
|
|
static int __kvm_timer_fn(struct kvm_vcpu *vcpu, struct kvm_timer *ktimer)
|
|
{
|
|
int restart_timer = 0;
|
|
wait_queue_head_t *q = &vcpu->wq;
|
|
|
|
/*
|
|
* There is a race window between reading and incrementing, but we do
|
|
* not care about potentially loosing timer events in the !reinject
|
|
* case anyway. Note: KVM_REQ_PENDING_TIMER is implicitly checked
|
|
* in vcpu_enter_guest.
|
|
*/
|
|
if (ktimer->reinject || !atomic_read(&ktimer->pending)) {
|
|
atomic_inc(&ktimer->pending);
|
|
/* FIXME: this code should not know anything about vcpus */
|
|
kvm_make_request(KVM_REQ_PENDING_TIMER, vcpu);
|
|
}
|
|
|
|
if (waitqueue_active(q))
|
|
wake_up_interruptible(q);
|
|
|
|
if (ktimer->t_ops->is_periodic(ktimer)) {
|
|
hrtimer_add_expires_ns(&ktimer->timer, ktimer->period);
|
|
restart_timer = 1;
|
|
}
|
|
|
|
return restart_timer;
|
|
}
|
|
|
|
enum hrtimer_restart kvm_timer_fn(struct hrtimer *data)
|
|
{
|
|
int restart_timer;
|
|
struct kvm_vcpu *vcpu;
|
|
struct kvm_timer *ktimer = container_of(data, struct kvm_timer, timer);
|
|
|
|
vcpu = ktimer->vcpu;
|
|
if (!vcpu)
|
|
return HRTIMER_NORESTART;
|
|
|
|
restart_timer = __kvm_timer_fn(vcpu, ktimer);
|
|
if (restart_timer)
|
|
return HRTIMER_RESTART;
|
|
else
|
|
return HRTIMER_NORESTART;
|
|
}
|
|
|