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>
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index ccc941a..d057c0c 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -38,7 +38,15 @@
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 @@
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 @@
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;
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 23c2176..df8bcb0 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -471,11 +471,8 @@
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)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 1687d12..fdf989f 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2038,9 +2038,7 @@
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 @@
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;