/**
* kvm_timer_sync_hwstate - sync timer state from cpu
* @vcpu: The vcpu pointer
*
* Check if the virtual timer was armed and either schedule a corresponding
* soft timer or inject directly if already expired.
*/
void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu)
{
struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
cycle_t cval, now;
u64 ns;
if ((timer->cntv_ctl & ARCH_TIMER_CTRL_IT_MASK) ||
!(timer->cntv_ctl & ARCH_TIMER_CTRL_ENABLE))
return;
cval = timer->cntv_cval;
now = kvm_phys_timer_read() - vcpu->kvm->arch.timer.cntvoff;
BUG_ON(timer_is_armed(timer));
if (cval <= now) {
/*
* Timer has already expired while we were not
* looking. Inject the interrupt and carry on.
*/
kvm_timer_inject_irq(vcpu);
return;
}
ns = cyclecounter_cyc2ns(timecounter->cc, cval - now);
timer_arm(timer, ns);
}
/*
* Schedule the background timer before calling kvm_vcpu_block, so that this
* thread is removed from its waitqueue and made runnable when there's a timer
* interrupt to handle.
*/
void kvm_timer_schedule(struct kvm_vcpu *vcpu)
{
struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
u64 ns;
cycle_t cval, now;
BUG_ON(timer_is_armed(timer));
/*
* No need to schedule a background timer if the guest timer has
* already expired, because kvm_vcpu_block will return before putting
* the thread to sleep.
*/
if (kvm_timer_should_fire(vcpu))
return;
/*
* If the timer is not capable of raising interrupts (disabled or
* masked), then there's no more work for us to do.
*/
if (!kvm_timer_irq_can_fire(vcpu))
return;
/* The timer has not yet expired, schedule a background timer */
cval = timer->cntv_cval;
now = kvm_phys_timer_read() - vcpu->kvm->arch.timer.cntvoff;
ns = cyclecounter_cyc2ns(timecounter->cc,
cval - now,
timecounter->mask,
&timecounter->frac);
timer_arm(timer, ns);
}
static void timer_disarm(struct arch_timer_cpu *timer)
{
if (timer_is_armed(timer)) {
hrtimer_cancel(&timer->timer);
cancel_work_sync(&timer->expired);
timer->armed = false;
}
}
/**
* kvm_timer_sync_hwstate - sync timer state from cpu
* @vcpu: The vcpu pointer
*
* Check if the virtual timer has expired while we were running in the guest,
* and inject an interrupt if that was the case.
*/
void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu)
{
struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
BUG_ON(timer_is_armed(timer));
/*
* The guest could have modified the timer registers or the timer
* could have expired, update the timer state.
*/
kvm_timer_update_state(vcpu);
}
