This patch changes the PIC interrupts delivery. Now it is only deliverd to vcpu0 when either condition is met (on vcpu0): 1. local APIC is hardware disabled 2. LVT0 is unmasked and configured to delivery mode ExtInt
It fixes the 2x faster wall clock on x86_64 and SMP i386 Linux guests
Signed-off-by: Qing He <[EMAIL PROTECTED]>
---
drivers/kvm/irq.c | 4 ++--
drivers/kvm/irq.h | 1 +
drivers/kvm/lapic.c | 17 +++++++++++++++++
3 files changed, 20 insertions(+), 2 deletions(-)
diff --git a/drivers/kvm/irq.c b/drivers/kvm/irq.c
index 608c530..0f663fe 100644
--- a/drivers/kvm/irq.c
+++ b/drivers/kvm/irq.c
@@ -33,7 +33,7 @@ int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
struct kvm_pic *s;
if (kvm_apic_has_interrupt(v) == -1) { /* LAPIC */
- if (v->vcpu_id == 0) {
+ if (kvm_apic_accept_pic_intr(v)) {
s = pic_irqchip(v->kvm); /* PIC */
return s->output;
} else
@@ -53,7 +53,7 @@ int kvm_cpu_get_interrupt(struct kvm_vcpu *v)
vector = kvm_get_apic_interrupt(v); /* APIC */
if (vector == -1) {
- if (v->vcpu_id == 0) {
+ if (kvm_apic_accept_pic_intr(v)) {
s = pic_irqchip(v->kvm);
s->output = 0; /* PIC */
vector = kvm_pic_read_irq(s);
diff --git a/drivers/kvm/irq.h b/drivers/kvm/irq.h
index 5f97e25..11fc014 100644
--- a/drivers/kvm/irq.h
+++ b/drivers/kvm/irq.h
@@ -135,6 +135,7 @@ do {
\
void kvm_vcpu_kick(struct kvm_vcpu *vcpu);
int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu);
+int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu);
int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu);
int kvm_create_lapic(struct kvm_vcpu *vcpu);
void kvm_lapic_reset(struct kvm_vcpu *vcpu);
diff --git a/drivers/kvm/lapic.c b/drivers/kvm/lapic.c
index 472a1c7..ddf9f20 100644
--- a/drivers/kvm/lapic.c
+++ b/drivers/kvm/lapic.c
@@ -836,6 +836,8 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu)
for (i = 0; i < APIC_LVT_NUM; i++)
apic_set_reg(apic, APIC_LVTT + 0x10 * i,
APIC_LVT_MASKED);
+ apic_set_reg(apic, APIC_LVT0,
+ SET_APIC_DELIVERY_MODE(0, APIC_MODE_EXTINT));
apic_set_reg(apic, APIC_DFR, 0xffffffffU);
apic_set_reg(apic, APIC_SPIV, 0xff);
@@ -984,6 +986,21 @@ int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu)
return highest_irr;
}
+int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu)
+{
+ u32 lvt0 = apic_get_reg(vcpu->apic, APIC_LVT0);
+ int r = 0;
+
+ if (vcpu->vcpu_id == 0) {
+ if (!apic_hw_enabled(vcpu->apic))
+ r = 1;
+ if ((lvt0 & APIC_LVT_MASKED) == 0 &&
+ GET_APIC_DELIVERY_MODE(lvt0) == APIC_MODE_EXTINT)
+ r = 1;
+ }
+ return r;
+}
+
void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->apic;
--
1.5.1.2
0001-kvm-apic-accept-pic-intr.patch
Description: 0001-kvm-apic-accept-pic-intr.patch
------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/
_______________________________________________ kvm-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/kvm-devel
