Commit a749e247 authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

KVM: lapic: reorganize restart_apic_timer 



Move the code to cancel the hv timer into the caller, just before
it starts the hrtimer.  Check availability of the hv timer in
start_hv_timer.

Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 35ee9e48

arch/x86/kvm/lapic.c

+40 −45
Original line number Diff line number Diff line
@@ -1495,17 +1495,21 @@ EXPORT_SYMBOL_GPL(kvm_lapic_hv_timer_in_use); 


static void cancel_hv_timer(struct kvm_lapic *apic)

{

	WARN_ON(!apic->lapic_timer.hv_timer_in_use);

	preempt_disable();

	kvm_x86_ops->cancel_hv_timer(apic->vcpu);

	apic->lapic_timer.hv_timer_in_use = false;

	preempt_enable();

}



static bool __start_hv_timer(struct kvm_lapic *apic)

static bool start_hv_timer(struct kvm_lapic *apic)

{

	struct kvm_timer *ktimer = &apic->lapic_timer;

	int r;



	if (!kvm_x86_ops->set_hv_timer)

		return false;



	if (!apic_lvtt_period(apic) && atomic_read(&ktimer->pending))

		return false;
@@ -1523,19 +1527,30 @@ static bool __start_hv_timer(struct kvm_lapic *apic) 
	 */

	if (!apic_lvtt_period(apic) && atomic_read(&ktimer->pending))

		return false;



	trace_kvm_hv_timer_state(apic->vcpu->vcpu_id, true);

	return true;

}



static bool start_hv_timer(struct kvm_lapic *apic)

static void start_sw_timer(struct kvm_lapic *apic)

{

	if (!__start_hv_timer(apic)) {

	struct kvm_timer *ktimer = &apic->lapic_timer;

	if (apic->lapic_timer.hv_timer_in_use)

		cancel_hv_timer(apic);

	if (!apic_lvtt_period(apic) && atomic_read(&ktimer->pending))

		return;



	if (apic_lvtt_period(apic) || apic_lvtt_oneshot(apic))

		start_sw_period(apic);

	else if (apic_lvtt_tscdeadline(apic))

		start_sw_tscdeadline(apic);

	trace_kvm_hv_timer_state(apic->vcpu->vcpu_id, false);

}



	trace_kvm_hv_timer_state(apic->vcpu->vcpu_id,

			apic->lapic_timer.hv_timer_in_use);

	return apic->lapic_timer.hv_timer_in_use;

static void restart_apic_timer(struct kvm_lapic *apic)

{

	if (!start_hv_timer(apic))

		start_sw_timer(apic);

}



void kvm_lapic_expired_hv_timer(struct kvm_vcpu *vcpu)
@@ -1549,19 +1564,14 @@ void kvm_lapic_expired_hv_timer(struct kvm_vcpu *vcpu) 


	if (apic_lvtt_period(apic) && apic->lapic_timer.period) {

		advance_periodic_target_expiration(apic);

		if (!start_hv_timer(apic))

			start_sw_period(apic);

		restart_apic_timer(apic);

	}

}

EXPORT_SYMBOL_GPL(kvm_lapic_expired_hv_timer);



void kvm_lapic_switch_to_hv_timer(struct kvm_vcpu *vcpu)

{

	struct kvm_lapic *apic = vcpu->arch.apic;



	WARN_ON(apic->lapic_timer.hv_timer_in_use);



	start_hv_timer(apic);

	restart_apic_timer(vcpu->arch.apic);

}

EXPORT_SYMBOL_GPL(kvm_lapic_switch_to_hv_timer);
@@ -1570,33 +1580,28 @@ void kvm_lapic_switch_to_sw_timer(struct kvm_vcpu *vcpu) 
	struct kvm_lapic *apic = vcpu->arch.apic;



	/* Possibly the TSC deadline timer is not enabled yet */

	if (!apic->lapic_timer.hv_timer_in_use)

		return;



	cancel_hv_timer(apic);

	if (apic->lapic_timer.hv_timer_in_use)

		start_sw_timer(apic);

}

EXPORT_SYMBOL_GPL(kvm_lapic_switch_to_sw_timer);



	if (atomic_read(&apic->lapic_timer.pending))

		return;

void kvm_lapic_restart_hv_timer(struct kvm_vcpu *vcpu)

{

	struct kvm_lapic *apic = vcpu->arch.apic;



	if (apic_lvtt_period(apic) || apic_lvtt_oneshot(apic))

		start_sw_period(apic);

	else if (apic_lvtt_tscdeadline(apic))

		start_sw_tscdeadline(apic);

	WARN_ON(!apic->lapic_timer.hv_timer_in_use);

	restart_apic_timer(apic);

}

EXPORT_SYMBOL_GPL(kvm_lapic_switch_to_sw_timer);



static void start_apic_timer(struct kvm_lapic *apic)

{

	atomic_set(&apic->lapic_timer.pending, 0);



	if (apic_lvtt_period(apic) || apic_lvtt_oneshot(apic)) {

		if (set_target_expiration(apic) &&

			!(kvm_x86_ops->set_hv_timer && start_hv_timer(apic)))

			start_sw_period(apic);

	} else if (apic_lvtt_tscdeadline(apic)) {

		if (!(kvm_x86_ops->set_hv_timer && start_hv_timer(apic)))

			start_sw_tscdeadline(apic);

	}

	if ((apic_lvtt_period(apic) || apic_lvtt_oneshot(apic))

	    && !set_target_expiration(apic))

		return;



	restart_apic_timer(apic);

}



static void apic_manage_nmi_watchdog(struct kvm_lapic *apic, u32 lvt0_val)
@@ -1827,16 +1832,6 @@ void kvm_free_lapic(struct kvm_vcpu *vcpu) 
 * LAPIC interface

 *----------------------------------------------------------------------

 */

u64 kvm_get_lapic_target_expiration_tsc(struct kvm_vcpu *vcpu)

{

	struct kvm_lapic *apic = vcpu->arch.apic;



	if (!lapic_in_kernel(vcpu))

		return 0;



	return apic->lapic_timer.tscdeadline;

}



u64 kvm_get_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu)

{

	struct kvm_lapic *apic = vcpu->arch.apic;

arch/x86/kvm/lapic.h

+1 −1
Original line number Diff line number Diff line
@@ -87,7 +87,6 @@ int kvm_apic_get_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s); 
int kvm_apic_set_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s);

int kvm_lapic_find_highest_irr(struct kvm_vcpu *vcpu);



u64 kvm_get_lapic_target_expiration_tsc(struct kvm_vcpu *vcpu);

u64 kvm_get_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu);

void kvm_set_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu, u64 data);
@@ -216,4 +215,5 @@ void kvm_lapic_switch_to_sw_timer(struct kvm_vcpu *vcpu); 
void kvm_lapic_switch_to_hv_timer(struct kvm_vcpu *vcpu);

void kvm_lapic_expired_hv_timer(struct kvm_vcpu *vcpu);

bool kvm_lapic_hv_timer_in_use(struct kvm_vcpu *vcpu);

void kvm_lapic_restart_hv_timer(struct kvm_vcpu *vcpu);

#endif

arch/x86/kvm/x86.c

+4 −4
Original line number Diff line number Diff line
@@ -2841,10 +2841,10 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) 
			kvm_vcpu_write_tsc_offset(vcpu, offset);

			vcpu->arch.tsc_catchup = 1;

		}

		if (kvm_lapic_hv_timer_in_use(vcpu) &&

				kvm_x86_ops->set_hv_timer(vcpu,

					kvm_get_lapic_target_expiration_tsc(vcpu)))

			kvm_lapic_switch_to_sw_timer(vcpu);



		if (kvm_lapic_hv_timer_in_use(vcpu))

			kvm_lapic_restart_hv_timer(vcpu);



		/*

		 * On a host with synchronized TSC, there is no need to update

		 * kvmclock on vcpu->cpu migration