Commit d3c7b77d authored by Marcelo Tosatti's avatar Marcelo Tosatti Committed by Avi Kivity
Browse files

KVM: unify part of generic timer handling 



Hide the internals of vcpu awakening / injection from the in-kernel
emulated timers. This makes future changes in this logic easier and
decreases the distance to more generic timer handling.

Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent fd668423

arch/x86/kvm/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -14,7 +14,7 @@ endif 
EXTRA_CFLAGS += -Ivirt/kvm -Iarch/x86/kvm



kvm-objs := $(common-objs) x86.o mmu.o x86_emulate.o i8259.o irq.o lapic.o \

	i8254.o

	i8254.o timer.o

obj-$(CONFIG_KVM) += kvm.o

kvm-intel-objs = vmx.o

obj-$(CONFIG_KVM_INTEL) += kvm-intel.o

arch/x86/kvm/i8254.c

+20 −37
Original line number Diff line number Diff line
@@ -219,25 +219,6 @@ static void pit_latch_status(struct kvm *kvm, int channel) 
	}

}



static int __pit_timer_fn(struct kvm_kpit_state *ps)

{

	struct kvm_vcpu *vcpu0 = ps->pit->kvm->vcpus[0];

	struct kvm_kpit_timer *pt = &ps->pit_timer;



	if (!atomic_inc_and_test(&pt->pending))

		set_bit(KVM_REQ_PENDING_TIMER, &vcpu0->requests);



	if (!pt->reinject)

		atomic_set(&pt->pending, 1);



	if (vcpu0 && waitqueue_active(&vcpu0->wq))

		wake_up_interruptible(&vcpu0->wq);



	hrtimer_add_expires_ns(&pt->timer, pt->period);



	return (pt->period == 0 ? 0 : 1);

}



int pit_has_pending_timer(struct kvm_vcpu *vcpu)

{

	struct kvm_pit *pit = vcpu->kvm->arch.vpit;
@@ -258,21 +239,6 @@ static void kvm_pit_ack_irq(struct kvm_irq_ack_notifier *kian) 
	spin_unlock(&ps->inject_lock);

}



static enum hrtimer_restart pit_timer_fn(struct hrtimer *data)

{

	struct kvm_kpit_state *ps;

	int restart_timer = 0;



	ps = container_of(data, struct kvm_kpit_state, pit_timer.timer);



	restart_timer = __pit_timer_fn(ps);



	if (restart_timer)

		return HRTIMER_RESTART;

	else

		return HRTIMER_NORESTART;

}



void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu)

{

	struct kvm_pit *pit = vcpu->kvm->arch.vpit;
@@ -286,15 +252,26 @@ void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu) 
		hrtimer_start_expires(timer, HRTIMER_MODE_ABS);

}



static void destroy_pit_timer(struct kvm_kpit_timer *pt)

static void destroy_pit_timer(struct kvm_timer *pt)

{

	pr_debug("pit: execute del timer!\n");

	hrtimer_cancel(&pt->timer);

}



static bool kpit_is_periodic(struct kvm_timer *ktimer)

{

	struct kvm_kpit_state *ps = container_of(ktimer, struct kvm_kpit_state,

						 pit_timer);

	return ps->is_periodic;

}



struct kvm_timer_ops kpit_ops = {

	.is_periodic = kpit_is_periodic,

};



static void create_pit_timer(struct kvm_kpit_state *ps, u32 val, int is_period)

{

	struct kvm_kpit_timer *pt = &ps->pit_timer;

	struct kvm_timer *pt = &ps->pit_timer;

	s64 interval;



	interval = muldiv64(val, NSEC_PER_SEC, KVM_PIT_FREQ);
@@ -304,7 +281,13 @@ static void create_pit_timer(struct kvm_kpit_state *ps, u32 val, int is_period) 
	/* TODO The new value only affected after the retriggered */

	hrtimer_cancel(&pt->timer);

	pt->period = (is_period == 0) ? 0 : interval;

	pt->timer.function = pit_timer_fn;

	ps->is_periodic = is_period;



	pt->timer.function = kvm_timer_fn;

	pt->t_ops = &kpit_ops;

	pt->kvm = ps->pit->kvm;

	pt->vcpu_id = 0;



	atomic_set(&pt->pending, 0);

	ps->irq_ack = 1;

arch/x86/kvm/i8254.h

+2 −9
Original line number Diff line number Diff line
@@ -3,14 +3,6 @@ 


#include "iodev.h"



struct kvm_kpit_timer {

	struct hrtimer timer;

	int irq;

	s64 period; /* unit: ns */

	atomic_t pending;

	bool reinject;

};



struct kvm_kpit_channel_state {

	u32 count; /* can be 65536 */

	u16 latched_count;
@@ -29,7 +21,8 @@ struct kvm_kpit_channel_state { 


struct kvm_kpit_state {

	struct kvm_kpit_channel_state channels[3];

	struct kvm_kpit_timer pit_timer;

	struct kvm_timer pit_timer;

	bool is_periodic;

	u32    speaker_data_on;

	struct mutex lock;

	struct kvm_pit *pit;

arch/x86/kvm/kvm_timer.h

0 → 100644
+18 −0
Original line number Diff line number Diff line 


struct kvm_timer {

	struct hrtimer timer;

	s64 period; 				/* unit: ns */

	atomic_t pending;			/* accumulated triggered timers */

	bool reinject;

	struct kvm_timer_ops *t_ops;

	struct kvm *kvm;

	int vcpu_id;

};



struct kvm_timer_ops {

        bool (*is_periodic)(struct kvm_timer *);

};





enum hrtimer_restart kvm_timer_fn(struct hrtimer *data);

arch/x86/kvm/lapic.c

+39 −55
Original line number Diff line number Diff line
@@ -528,12 +528,13 @@ static u32 apic_get_tmcct(struct kvm_lapic *apic) 
	if (apic_get_reg(apic, APIC_TMICT) == 0)

		return 0;



	remaining = hrtimer_expires_remaining(&apic->timer.dev);

	remaining = hrtimer_expires_remaining(&apic->lapic_timer.timer);

	if (ktime_to_ns(remaining) < 0)

		remaining = ktime_set(0, 0);



	ns = mod_64(ktime_to_ns(remaining), apic->timer.period);

	tmcct = div64_u64(ns, (APIC_BUS_CYCLE_NS * apic->timer.divide_count));

	ns = mod_64(ktime_to_ns(remaining), apic->lapic_timer.period);

	tmcct = div64_u64(ns,

			 (APIC_BUS_CYCLE_NS * apic->divide_count));



	return tmcct;

}
@@ -620,25 +621,25 @@ static void update_divide_count(struct kvm_lapic *apic) 
	tdcr = apic_get_reg(apic, APIC_TDCR);

	tmp1 = tdcr & 0xf;

	tmp2 = ((tmp1 & 0x3) | ((tmp1 & 0x8) >> 1)) + 1;

	apic->timer.divide_count = 0x1 << (tmp2 & 0x7);

	apic->divide_count = 0x1 << (tmp2 & 0x7);



	apic_debug("timer divide count is 0x%x\n",

				   apic->timer.divide_count);

				   apic->lapic_timer.divide_count);

}



static void start_apic_timer(struct kvm_lapic *apic)

{

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

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



	apic->timer.period = apic_get_reg(apic, APIC_TMICT) *

		    APIC_BUS_CYCLE_NS * apic->timer.divide_count;

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

	apic->lapic_timer.period = apic_get_reg(apic, APIC_TMICT) *

		    APIC_BUS_CYCLE_NS * apic->divide_count;

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



	if (!apic->timer.period)

	if (!apic->lapic_timer.period)

		return;



	hrtimer_start(&apic->timer.dev,

		      ktime_add_ns(now, apic->timer.period),

	hrtimer_start(&apic->lapic_timer.timer,

		      ktime_add_ns(now, apic->lapic_timer.period),

		      HRTIMER_MODE_ABS);



	apic_debug("%s: bus cycle is %" PRId64 "ns, now 0x%016"
@@ -647,9 +648,9 @@ static void start_apic_timer(struct kvm_lapic *apic) 
			   "expire @ 0x%016" PRIx64 ".\n", __func__,

			   APIC_BUS_CYCLE_NS, ktime_to_ns(now),

			   apic_get_reg(apic, APIC_TMICT),

			   apic->timer.period,

			   apic->lapic_timer.period,

			   ktime_to_ns(ktime_add_ns(now,

					apic->timer.period)));

					apic->lapic_timer.period)));

}



static void apic_manage_nmi_watchdog(struct kvm_lapic *apic, u32 lvt0_val)
@@ -731,7 +732,7 @@ static void apic_mmio_write(struct kvm_io_device *this, 
				apic_set_reg(apic, APIC_LVTT + 0x10 * i,

					     lvt_val | APIC_LVT_MASKED);

			}

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

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



		}

		break;
@@ -763,7 +764,7 @@ static void apic_mmio_write(struct kvm_io_device *this, 
		break;



	case APIC_TMICT:

		hrtimer_cancel(&apic->timer.dev);

		hrtimer_cancel(&apic->lapic_timer.timer);

		apic_set_reg(apic, APIC_TMICT, val);

		start_apic_timer(apic);

		return;
@@ -803,7 +804,7 @@ void kvm_free_lapic(struct kvm_vcpu *vcpu) 
	if (!vcpu->arch.apic)

		return;



	hrtimer_cancel(&vcpu->arch.apic->timer.dev);

	hrtimer_cancel(&vcpu->arch.apic->lapic_timer.timer);



	if (vcpu->arch.apic->regs_page)

		__free_page(vcpu->arch.apic->regs_page);
@@ -881,7 +882,7 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu) 
	ASSERT(apic != NULL);



	/* Stop the timer in case it's a reset to an active apic */

	hrtimer_cancel(&apic->timer.dev);

	hrtimer_cancel(&apic->lapic_timer.timer);



	apic_set_reg(apic, APIC_ID, vcpu->vcpu_id << 24);

	apic_set_reg(apic, APIC_LVR, APIC_VERSION);
@@ -906,7 +907,7 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu) 
		apic_set_reg(apic, APIC_TMR + 0x10 * i, 0);

	}

	update_divide_count(apic);

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

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

	if (vcpu->vcpu_id == 0)

		vcpu->arch.apic_base |= MSR_IA32_APICBASE_BSP;

	apic_update_ppr(apic);
@@ -937,22 +938,11 @@ EXPORT_SYMBOL_GPL(kvm_lapic_enabled); 
 *----------------------------------------------------------------------

 */



/* TODO: make sure __apic_timer_fn runs in current pCPU */

static int __apic_timer_fn(struct kvm_lapic *apic)

static bool lapic_is_periodic(struct kvm_timer *ktimer)

{

	int result = 0;

	wait_queue_head_t *q = &apic->vcpu->wq;



	if(!atomic_inc_and_test(&apic->timer.pending))

		set_bit(KVM_REQ_PENDING_TIMER, &apic->vcpu->requests);

	if (waitqueue_active(q))

		wake_up_interruptible(q);



	if (apic_lvtt_period(apic)) {

		result = 1;

		hrtimer_add_expires_ns(&apic->timer.dev, apic->timer.period);

	}

	return result;

	struct kvm_lapic *apic = container_of(ktimer, struct kvm_lapic,

					      lapic_timer);

	return apic_lvtt_period(apic);

}



int apic_has_pending_timer(struct kvm_vcpu *vcpu)
@@ -960,7 +950,7 @@ int apic_has_pending_timer(struct kvm_vcpu *vcpu) 
	struct kvm_lapic *lapic = vcpu->arch.apic;



	if (lapic && apic_enabled(lapic) && apic_lvt_enabled(lapic, APIC_LVTT))

		return atomic_read(&lapic->timer.pending);

		return atomic_read(&lapic->lapic_timer.pending);



	return 0;

}
@@ -987,20 +977,9 @@ void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu) 
		kvm_apic_local_deliver(apic, APIC_LVT0);

}



static enum hrtimer_restart apic_timer_fn(struct hrtimer *data)

{

	struct kvm_lapic *apic;

	int restart_timer = 0;



	apic = container_of(data, struct kvm_lapic, timer.dev);



	restart_timer = __apic_timer_fn(apic);



	if (restart_timer)

		return HRTIMER_RESTART;

	else

		return HRTIMER_NORESTART;

}

struct kvm_timer_ops lapic_timer_ops = {

	.is_periodic = lapic_is_periodic,

};



int kvm_create_lapic(struct kvm_vcpu *vcpu)

{
@@ -1025,8 +1004,13 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu) 
	memset(apic->regs, 0, PAGE_SIZE);

	apic->vcpu = vcpu;



	hrtimer_init(&apic->timer.dev, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);

	apic->timer.dev.function = apic_timer_fn;

	hrtimer_init(&apic->lapic_timer.timer, CLOCK_MONOTONIC,

		     HRTIMER_MODE_ABS);

	apic->lapic_timer.timer.function = kvm_timer_fn;

	apic->lapic_timer.t_ops = &lapic_timer_ops;

	apic->lapic_timer.kvm = vcpu->kvm;

	apic->lapic_timer.vcpu_id = vcpu->vcpu_id;



	apic->base_address = APIC_DEFAULT_PHYS_BASE;

	vcpu->arch.apic_base = APIC_DEFAULT_PHYS_BASE;
@@ -1079,9 +1063,9 @@ void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu) 
{

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



	if (apic && atomic_read(&apic->timer.pending) > 0) {

	if (apic && atomic_read(&apic->lapic_timer.pending) > 0) {

		if (kvm_apic_local_deliver(apic, APIC_LVTT))

			atomic_dec(&apic->timer.pending);

			atomic_dec(&apic->lapic_timer.pending);

	}

}
@@ -1107,7 +1091,7 @@ void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu) 
			     MSR_IA32_APICBASE_BASE;

	apic_set_reg(apic, APIC_LVR, APIC_VERSION);

	apic_update_ppr(apic);

	hrtimer_cancel(&apic->timer.dev);

	hrtimer_cancel(&apic->lapic_timer.timer);

	update_divide_count(apic);

	start_apic_timer(apic);

}
@@ -1120,7 +1104,7 @@ void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu) 
	if (!apic)

		return;



	timer = &apic->timer.dev;

	timer = &apic->lapic_timer.timer;

	if (hrtimer_cancel(timer))

		hrtimer_start_expires(timer, HRTIMER_MODE_ABS);

}

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