KVM: Move IO APIC to its own lock

The allows removal of irq_lock from the injection path.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Gleb Natapov 2009-08-24 11:54:25 +03:00 committed by Avi Kivity
parent 280aa177dc
commit eba0226bdf
7 changed files with 100 additions and 51 deletions

View File

@ -851,8 +851,7 @@ static int kvm_vm_ioctl_get_irqchip(struct kvm *kvm,
r = 0;
switch (chip->chip_id) {
case KVM_IRQCHIP_IOAPIC:
memcpy(&chip->chip.ioapic, ioapic_irqchip(kvm),
sizeof(struct kvm_ioapic_state));
r = kvm_get_ioapic(kvm, &chip->chip.ioapic);
break;
default:
r = -EINVAL;
@ -868,9 +867,7 @@ static int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
r = 0;
switch (chip->chip_id) {
case KVM_IRQCHIP_IOAPIC:
memcpy(ioapic_irqchip(kvm),
&chip->chip.ioapic,
sizeof(struct kvm_ioapic_state));
r = kvm_set_ioapic(kvm, &chip->chip.ioapic);
break;
default:
r = -EINVAL;

View File

@ -38,7 +38,15 @@ static void pic_clear_isr(struct kvm_kpic_state *s, int irq)
s->isr_ack |= (1 << irq);
if (s != &s->pics_state->pics[0])
irq += 8;
/*
* We are dropping lock while calling ack notifiers since ack
* notifier callbacks for assigned devices call into PIC recursively.
* Other interrupt may be delivered to PIC while lock is dropped but
* it should be safe since PIC state is already updated at this stage.
*/
spin_unlock(&s->pics_state->lock);
kvm_notify_acked_irq(s->pics_state->kvm, SELECT_PIC(irq), irq);
spin_lock(&s->pics_state->lock);
}
void kvm_pic_clear_isr_ack(struct kvm *kvm)
@ -176,16 +184,18 @@ int kvm_pic_set_irq(void *opaque, int irq, int level)
static inline void pic_intack(struct kvm_kpic_state *s, int irq)
{
s->isr |= 1 << irq;
if (s->auto_eoi) {
if (s->rotate_on_auto_eoi)
s->priority_add = (irq + 1) & 7;
pic_clear_isr(s, irq);
}
/*
* We don't clear a level sensitive interrupt here
*/
if (!(s->elcr & (1 << irq)))
s->irr &= ~(1 << irq);
if (s->auto_eoi) {
if (s->rotate_on_auto_eoi)
s->priority_add = (irq + 1) & 7;
pic_clear_isr(s, irq);
}
}
int kvm_pic_read_irq(struct kvm *kvm)
@ -294,9 +304,9 @@ static void pic_ioport_write(void *opaque, u32 addr, u32 val)
priority = get_priority(s, s->isr);
if (priority != 8) {
irq = (priority + s->priority_add) & 7;
pic_clear_isr(s, irq);
if (cmd == 5)
s->priority_add = (irq + 1) & 7;
pic_clear_isr(s, irq);
pic_update_irq(s->pics_state);
}
break;

View File

@ -471,11 +471,8 @@ static void apic_set_eoi(struct kvm_lapic *apic)
trigger_mode = IOAPIC_LEVEL_TRIG;
else
trigger_mode = IOAPIC_EDGE_TRIG;
if (!(apic_get_reg(apic, APIC_SPIV) & APIC_SPIV_DIRECTED_EOI)) {
mutex_lock(&apic->vcpu->kvm->irq_lock);
if (!(apic_get_reg(apic, APIC_SPIV) & APIC_SPIV_DIRECTED_EOI))
kvm_ioapic_update_eoi(apic->vcpu->kvm, vector, trigger_mode);
mutex_unlock(&apic->vcpu->kvm->irq_lock);
}
}
static void apic_send_ipi(struct kvm_lapic *apic)

View File

@ -2038,9 +2038,7 @@ static int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
sizeof(struct kvm_pic_state));
break;
case KVM_IRQCHIP_IOAPIC:
memcpy(&chip->chip.ioapic,
ioapic_irqchip(kvm),
sizeof(struct kvm_ioapic_state));
r = kvm_get_ioapic(kvm, &chip->chip.ioapic);
break;
default:
r = -EINVAL;
@ -2070,11 +2068,7 @@ static int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
spin_unlock(&pic_irqchip(kvm)->lock);
break;
case KVM_IRQCHIP_IOAPIC:
mutex_lock(&kvm->irq_lock);
memcpy(ioapic_irqchip(kvm),
&chip->chip.ioapic,
sizeof(struct kvm_ioapic_state));
mutex_unlock(&kvm->irq_lock);
r = kvm_set_ioapic(kvm, &chip->chip.ioapic);
break;
default:
r = -EINVAL;

View File

@ -182,6 +182,7 @@ int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level)
union kvm_ioapic_redirect_entry entry;
int ret = 1;
mutex_lock(&ioapic->lock);
if (irq >= 0 && irq < IOAPIC_NUM_PINS) {
entry = ioapic->redirtbl[irq];
level ^= entry.fields.polarity;
@ -198,34 +199,51 @@ int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level)
}
trace_kvm_ioapic_set_irq(entry.bits, irq, ret == 0);
}
mutex_unlock(&ioapic->lock);
return ret;
}
static void __kvm_ioapic_update_eoi(struct kvm_ioapic *ioapic, int pin,
static void __kvm_ioapic_update_eoi(struct kvm_ioapic *ioapic, int vector,
int trigger_mode)
{
union kvm_ioapic_redirect_entry *ent;
int i;
ent = &ioapic->redirtbl[pin];
for (i = 0; i < IOAPIC_NUM_PINS; i++) {
union kvm_ioapic_redirect_entry *ent = &ioapic->redirtbl[i];
kvm_notify_acked_irq(ioapic->kvm, KVM_IRQCHIP_IOAPIC, pin);
if (ent->fields.vector != vector)
continue;
/*
* We are dropping lock while calling ack notifiers because ack
* notifier callbacks for assigned devices call into IOAPIC
* recursively. Since remote_irr is cleared only after call
* to notifiers if the same vector will be delivered while lock
* is dropped it will be put into irr and will be delivered
* after ack notifier returns.
*/
mutex_unlock(&ioapic->lock);
kvm_notify_acked_irq(ioapic->kvm, KVM_IRQCHIP_IOAPIC, i);
mutex_lock(&ioapic->lock);
if (trigger_mode != IOAPIC_LEVEL_TRIG)
continue;
if (trigger_mode == IOAPIC_LEVEL_TRIG) {
ASSERT(ent->fields.trig_mode == IOAPIC_LEVEL_TRIG);
ent->fields.remote_irr = 0;
if (!ent->fields.mask && (ioapic->irr & (1 << pin)))
ioapic_service(ioapic, pin);
if (!ent->fields.mask && (ioapic->irr & (1 << i)))
ioapic_service(ioapic, i);
}
}
void kvm_ioapic_update_eoi(struct kvm *kvm, int vector, int trigger_mode)
{
struct kvm_ioapic *ioapic = kvm->arch.vioapic;
int i;
for (i = 0; i < IOAPIC_NUM_PINS; i++)
if (ioapic->redirtbl[i].fields.vector == vector)
__kvm_ioapic_update_eoi(ioapic, i, trigger_mode);
mutex_lock(&ioapic->lock);
__kvm_ioapic_update_eoi(ioapic, vector, trigger_mode);
mutex_unlock(&ioapic->lock);
}
static inline struct kvm_ioapic *to_ioapic(struct kvm_io_device *dev)
@ -250,8 +268,8 @@ static int ioapic_mmio_read(struct kvm_io_device *this, gpa_t addr, int len,
ioapic_debug("addr %lx\n", (unsigned long)addr);
ASSERT(!(addr & 0xf)); /* check alignment */
mutex_lock(&ioapic->kvm->irq_lock);
addr &= 0xff;
mutex_lock(&ioapic->lock);
switch (addr) {
case IOAPIC_REG_SELECT:
result = ioapic->ioregsel;
@ -265,6 +283,8 @@ static int ioapic_mmio_read(struct kvm_io_device *this, gpa_t addr, int len,
result = 0;
break;
}
mutex_unlock(&ioapic->lock);
switch (len) {
case 8:
*(u64 *) val = result;
@ -277,7 +297,6 @@ static int ioapic_mmio_read(struct kvm_io_device *this, gpa_t addr, int len,
default:
printk(KERN_WARNING "ioapic: wrong length %d\n", len);
}
mutex_unlock(&ioapic->kvm->irq_lock);
return 0;
}
@ -293,15 +312,15 @@ static int ioapic_mmio_write(struct kvm_io_device *this, gpa_t addr, int len,
(void*)addr, len, val);
ASSERT(!(addr & 0xf)); /* check alignment */
mutex_lock(&ioapic->kvm->irq_lock);
if (len == 4 || len == 8)
data = *(u32 *) val;
else {
printk(KERN_WARNING "ioapic: Unsupported size %d\n", len);
goto unlock;
return 0;
}
addr &= 0xff;
mutex_lock(&ioapic->lock);
switch (addr) {
case IOAPIC_REG_SELECT:
ioapic->ioregsel = data;
@ -312,15 +331,14 @@ static int ioapic_mmio_write(struct kvm_io_device *this, gpa_t addr, int len,
break;
#ifdef CONFIG_IA64
case IOAPIC_REG_EOI:
kvm_ioapic_update_eoi(ioapic->kvm, data, IOAPIC_LEVEL_TRIG);
__kvm_ioapic_update_eoi(ioapic, data, IOAPIC_LEVEL_TRIG);
break;
#endif
default:
break;
}
unlock:
mutex_unlock(&ioapic->kvm->irq_lock);
mutex_unlock(&ioapic->lock);
return 0;
}
@ -349,6 +367,7 @@ int kvm_ioapic_init(struct kvm *kvm)
ioapic = kzalloc(sizeof(struct kvm_ioapic), GFP_KERNEL);
if (!ioapic)
return -ENOMEM;
mutex_init(&ioapic->lock);
kvm->arch.vioapic = ioapic;
kvm_ioapic_reset(ioapic);
kvm_iodevice_init(&ioapic->dev, &ioapic_mmio_ops);
@ -360,3 +379,26 @@ int kvm_ioapic_init(struct kvm *kvm)
return ret;
}
int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
{
struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
if (!ioapic)
return -EINVAL;
mutex_lock(&ioapic->lock);
memcpy(state, ioapic, sizeof(struct kvm_ioapic_state));
mutex_unlock(&ioapic->lock);
return 0;
}
int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
{
struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
if (!ioapic)
return -EINVAL;
mutex_lock(&ioapic->lock);
memcpy(ioapic, state, sizeof(struct kvm_ioapic_state));
mutex_unlock(&ioapic->lock);
return 0;
}

View File

@ -45,6 +45,7 @@ struct kvm_ioapic {
struct kvm_io_device dev;
struct kvm *kvm;
void (*ack_notifier)(void *opaque, int irq);
struct mutex lock;
};
#ifdef DEBUG
@ -74,4 +75,7 @@ int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level);
void kvm_ioapic_reset(struct kvm_ioapic *ioapic);
int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
struct kvm_lapic_irq *irq);
int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
#endif

View File

@ -146,8 +146,8 @@ static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
*/
int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level)
{
struct kvm_kernel_irq_routing_entry *e;
int ret = -1;
struct kvm_kernel_irq_routing_entry *e, irq_set[KVM_NR_IRQCHIPS];
int ret = -1, i = 0;
struct kvm_irq_routing_table *irq_rt;
struct hlist_node *n;
@ -162,14 +162,19 @@ int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level)
rcu_read_lock();
irq_rt = rcu_dereference(kvm->irq_routing);
if (irq < irq_rt->nr_rt_entries)
hlist_for_each_entry(e, n, &irq_rt->map[irq], link) {
int r = e->set(e, kvm, irq_source_id, level);
hlist_for_each_entry(e, n, &irq_rt->map[irq], link)
irq_set[i++] = *e;
rcu_read_unlock();
while(i--) {
int r;
r = irq_set[i].set(&irq_set[i], kvm, irq_source_id, level);
if (r < 0)
continue;
ret = r + ((ret < 0) ? 0 : ret);
}
rcu_read_unlock();
return ret;
}