KVM: x86: Fix and refactor NMI watchdog emulation

This patch refactors the NMI watchdog delivery patch, consolidating
tests and providing a proper API for delivering watchdog events.

An included micro-optimization is to check only for apic_hw_enabled in
kvm_apic_local_deliver (the test for LVT mask is covering the
soft-disabled case already).

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Jan Kiszka 2008-10-20 10:20:02 +02:00 committed by Avi Kivity
parent 291fd39bfc
commit 8fdb2351d5
3 changed files with 20 additions and 17 deletions

View file

@ -612,15 +612,18 @@ static void __inject_pit_timer_intr(struct kvm *kvm)
mutex_unlock(&kvm->lock);
/*
* Provides NMI watchdog support in IOAPIC mode.
* The route is: PIT -> PIC -> LVT0 in NMI mode,
* timer IRQs will continue to flow through the IOAPIC.
* Provides NMI watchdog support via Virtual Wire mode.
* The route is: PIT -> PIC -> LVT0 in NMI mode.
*
* Note: Our Virtual Wire implementation is simplified, only
* propagating PIT interrupts to all VCPUs when they have set
* LVT0 to NMI delivery. Other PIC interrupts are just sent to
* VCPU0, and only if its LVT0 is in EXTINT mode.
*/
for (i = 0; i < KVM_MAX_VCPUS; ++i) {
vcpu = kvm->vcpus[i];
if (!vcpu)
continue;
kvm_apic_local_deliver(vcpu, APIC_LVT0);
if (vcpu)
kvm_apic_nmi_wd_deliver(vcpu);
}
}

View file

@ -87,7 +87,7 @@ void kvm_pic_reset(struct kvm_kpic_state *s);
void kvm_timer_intr_post(struct kvm_vcpu *vcpu, int vec);
void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu);
void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu);
int kvm_apic_local_deliver(struct kvm_vcpu *vcpu, int lvt_type);
void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu);
void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu);
void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu);
void __kvm_migrate_timers(struct kvm_vcpu *vcpu);

View file

@ -973,14 +973,12 @@ int apic_has_pending_timer(struct kvm_vcpu *vcpu)
return 0;
}
int kvm_apic_local_deliver(struct kvm_vcpu *vcpu, int lvt_type)
static int kvm_apic_local_deliver(struct kvm_lapic *apic, int lvt_type)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u32 reg = apic_get_reg(apic, lvt_type);
int vector, mode, trig_mode;
u32 reg;
if (apic && apic_enabled(apic)) {
reg = apic_get_reg(apic, lvt_type);
if (apic_hw_enabled(apic) && !(reg & APIC_LVT_MASKED)) {
vector = reg & APIC_VECTOR_MASK;
mode = reg & APIC_MODE_MASK;
trig_mode = reg & APIC_LVT_LEVEL_TRIGGER;
@ -989,9 +987,12 @@ int kvm_apic_local_deliver(struct kvm_vcpu *vcpu, int lvt_type)
return 0;
}
static inline int __inject_apic_timer_irq(struct kvm_lapic *apic)
void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu)
{
return kvm_apic_local_deliver(apic->vcpu, APIC_LVTT);
struct kvm_lapic *apic = vcpu->arch.apic;
if (apic)
kvm_apic_local_deliver(apic, APIC_LVT0);
}
static enum hrtimer_restart apic_timer_fn(struct hrtimer *data)
@ -1086,9 +1087,8 @@ void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
if (apic && apic_lvt_enabled(apic, APIC_LVTT) &&
atomic_read(&apic->timer.pending) > 0) {
if (__inject_apic_timer_irq(apic))
if (apic && atomic_read(&apic->timer.pending) > 0) {
if (kvm_apic_local_deliver(apic, APIC_LVTT))
atomic_dec(&apic->timer.pending);
}
}