Commit 53f9eedf authored by Yunhong Jiang's avatar Yunhong Jiang Committed by Paolo Bonzini
Browse files

kvm: lapic: separate start_sw_tscdeadline from start_apic_timer 



The function to start the tsc deadline timer virtualization will be used
also by the pre_block hook when we use the preemption timer; change it
to a separate function. No logic changes.

Signed-off-by: default avatarYunhong Jiang <yunhong.jiang@intel.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent a03825bb

arch/x86/kvm/lapic.c

+31 −26
Original line number Diff line number Diff line
@@ -1313,6 +1313,36 @@ void wait_lapic_expire(struct kvm_vcpu *vcpu) 
		__delay(tsc_deadline - guest_tsc);

}



static void start_sw_tscdeadline(struct kvm_lapic *apic)

{

	u64 guest_tsc, tscdeadline = apic->lapic_timer.tscdeadline;

	u64 ns = 0;

	ktime_t expire;

	struct kvm_vcpu *vcpu = apic->vcpu;

	unsigned long this_tsc_khz = vcpu->arch.virtual_tsc_khz;

	unsigned long flags;

	ktime_t now;



	if (unlikely(!tscdeadline || !this_tsc_khz))

		return;



	local_irq_save(flags);



	now = apic->lapic_timer.timer.base->get_time();

	guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());

	if (likely(tscdeadline > guest_tsc)) {

		ns = (tscdeadline - guest_tsc) * 1000000ULL;

		do_div(ns, this_tsc_khz);

		expire = ktime_add_ns(now, ns);

		expire = ktime_sub_ns(expire, lapic_timer_advance_ns);

		hrtimer_start(&apic->lapic_timer.timer,

				expire, HRTIMER_MODE_ABS_PINNED);

	} else

		apic_timer_expired(apic);



	local_irq_restore(flags);

}



static void start_apic_timer(struct kvm_lapic *apic)

{

	ktime_t now;
@@ -1359,32 +1389,7 @@ static void start_apic_timer(struct kvm_lapic *apic) 
			   ktime_to_ns(ktime_add_ns(now,

					apic->lapic_timer.period)));

	} else if (apic_lvtt_tscdeadline(apic)) {

		/* lapic timer in tsc deadline mode */

		u64 guest_tsc, tscdeadline = apic->lapic_timer.tscdeadline;

		u64 ns = 0;

		ktime_t expire;

		struct kvm_vcpu *vcpu = apic->vcpu;

		unsigned long this_tsc_khz = vcpu->arch.virtual_tsc_khz;

		unsigned long flags;



		if (unlikely(!tscdeadline || !this_tsc_khz))

			return;



		local_irq_save(flags);



		now = apic->lapic_timer.timer.base->get_time();

		guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());

		if (likely(tscdeadline > guest_tsc)) {

			ns = (tscdeadline - guest_tsc) * 1000000ULL;

			do_div(ns, this_tsc_khz);

			expire = ktime_add_ns(now, ns);

			expire = ktime_sub_ns(expire, lapic_timer_advance_ns);

			hrtimer_start(&apic->lapic_timer.timer,

				      expire, HRTIMER_MODE_ABS_PINNED);

		} else

			apic_timer_expired(apic);



		local_irq_restore(flags);

		start_sw_tscdeadline(apic);

	}

}