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authorQing He <qing.he@intel.com>2007-09-17 02:47:13 -0400
committerAvi Kivity <avi@qumranet.com>2007-10-13 04:18:26 -0400
commit40487c680d5855459dfdce340df13d40071bb774 (patch)
treeabc0ec56ecb1b6d1533b918621c060a1d38fccef /drivers/kvm
parent5cd4f6fd8506f59cb8a232f364c54f6bd8e5150a (diff)
KVM: deliver PIC interrupt only to vcpu0
This patch changes the PIC interrupts delivery. Now it is only delivered 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: Eddie (Yaozu) Dong <eddie.dong@intel.com> Signed-off-by: Qing He <qing.he@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Diffstat (limited to 'drivers/kvm')
-rw-r--r--drivers/kvm/irq.c15
-rw-r--r--drivers/kvm/irq.h1
-rw-r--r--drivers/kvm/lapic.c17
3 files changed, 28 insertions, 5 deletions
diff --git a/drivers/kvm/irq.c b/drivers/kvm/irq.c
index b88e50115588..7628c7ff628f 100644
--- a/drivers/kvm/irq.c
+++ b/drivers/kvm/irq.c
@@ -33,8 +33,11 @@ int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
33 struct kvm_pic *s; 33 struct kvm_pic *s;
34 34
35 if (kvm_apic_has_interrupt(v) == -1) { /* LAPIC */ 35 if (kvm_apic_has_interrupt(v) == -1) { /* LAPIC */
36 s = pic_irqchip(v->kvm); /* PIC */ 36 if (kvm_apic_accept_pic_intr(v)) {
37 return s->output; 37 s = pic_irqchip(v->kvm); /* PIC */
38 return s->output;
39 } else
40 return 0;
38 } 41 }
39 return 1; 42 return 1;
40} 43}
@@ -50,9 +53,11 @@ int kvm_cpu_get_interrupt(struct kvm_vcpu *v)
50 53
51 vector = kvm_get_apic_interrupt(v); /* APIC */ 54 vector = kvm_get_apic_interrupt(v); /* APIC */
52 if (vector == -1) { 55 if (vector == -1) {
53 s = pic_irqchip(v->kvm); 56 if (kvm_apic_accept_pic_intr(v)) {
54 s->output = 0; /* PIC */ 57 s = pic_irqchip(v->kvm);
55 vector = kvm_pic_read_irq(s); 58 s->output = 0; /* PIC */
59 vector = kvm_pic_read_irq(s);
60 }
56 } 61 }
57 return vector; 62 return vector;
58} 63}
diff --git a/drivers/kvm/irq.h b/drivers/kvm/irq.h
index f324cfb40084..ec46a09e2135 100644
--- a/drivers/kvm/irq.h
+++ b/drivers/kvm/irq.h
@@ -135,6 +135,7 @@ do { \
135 135
136void kvm_vcpu_kick(struct kvm_vcpu *vcpu); 136void kvm_vcpu_kick(struct kvm_vcpu *vcpu);
137int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu); 137int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu);
138int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu);
138int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu); 139int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu);
139int kvm_create_lapic(struct kvm_vcpu *vcpu); 140int kvm_create_lapic(struct kvm_vcpu *vcpu);
140void kvm_free_apic(struct kvm_lapic *apic); 141void kvm_free_apic(struct kvm_lapic *apic);
diff --git a/drivers/kvm/lapic.c b/drivers/kvm/lapic.c
index 2706ec36c258..01e769672dcc 100644
--- a/drivers/kvm/lapic.c
+++ b/drivers/kvm/lapic.c
@@ -788,6 +788,8 @@ static void lapic_reset(struct kvm_vcpu *vcpu)
788 788
789 for (i = 0; i < APIC_LVT_NUM; i++) 789 for (i = 0; i < APIC_LVT_NUM; i++)
790 apic_set_reg(apic, APIC_LVTT + 0x10 * i, APIC_LVT_MASKED); 790 apic_set_reg(apic, APIC_LVTT + 0x10 * i, APIC_LVT_MASKED);
791 apic_set_reg(apic, APIC_LVT0,
792 SET_APIC_DELIVERY_MODE(0, APIC_MODE_EXTINT));
791 793
792 apic_set_reg(apic, APIC_DFR, 0xffffffffU); 794 apic_set_reg(apic, APIC_DFR, 0xffffffffU);
793 apic_set_reg(apic, APIC_SPIV, 0xff); 795 apic_set_reg(apic, APIC_SPIV, 0xff);
@@ -932,6 +934,21 @@ int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu)
932 return highest_irr; 934 return highest_irr;
933} 935}
934 936
937int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu)
938{
939 u32 lvt0 = apic_get_reg(vcpu->apic, APIC_LVT0);
940 int r = 0;
941
942 if (vcpu->vcpu_id == 0) {
943 if (!apic_hw_enabled(vcpu->apic))
944 r = 1;
945 if ((lvt0 & APIC_LVT_MASKED) == 0 &&
946 GET_APIC_DELIVERY_MODE(lvt0) == APIC_MODE_EXTINT)
947 r = 1;
948 }
949 return r;
950}
951
935void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu) 952void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu)
936{ 953{
937 struct kvm_lapic *apic = vcpu->apic; 954 struct kvm_lapic *apic = vcpu->apic;