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authorGleb Natapov <gleb@redhat.com>2009-02-04 18:28:14 +0300
committerAvi Kivity <avi@redhat.com>2009-03-24 12:03:11 +0300
commit4925663a079c77d95d8685228ad6675fc5639c8e (patch)
tree52e93df78b23a44ed21d015f835688f673dd351a /arch/x86/kvm/i8259.c
parent452425dbaa1974e9fc489e64a8de46a47b4c2754 (diff)
downloadlinux-4925663a079c77d95d8685228ad6675fc5639c8e.tar.xz
KVM: Report IRQ injection status to userspace.
IRQ injection status is either -1 (if there was no CPU found that should except the interrupt because IRQ was masked or ioapic was misconfigured or ...) or >= 0 in that case the number indicates to how many CPUs interrupt was injected. If the value is 0 it means that the interrupt was coalesced and probably should be reinjected. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch/x86/kvm/i8259.c')
-rw-r--r--arch/x86/kvm/i8259.c18
1 files changed, 13 insertions, 5 deletions
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index 93160375c841..b4e662e94ddc 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -77,12 +77,13 @@ void kvm_pic_clear_isr_ack(struct kvm *kvm)
/*
* set irq level. If an edge is detected, then the IRR is set to 1
*/
-static inline void pic_set_irq1(struct kvm_kpic_state *s, int irq, int level)
+static inline int pic_set_irq1(struct kvm_kpic_state *s, int irq, int level)
{
- int mask;
+ int mask, ret = 1;
mask = 1 << irq;
if (s->elcr & mask) /* level triggered */
if (level) {
+ ret = !(s->irr & mask);
s->irr |= mask;
s->last_irr |= mask;
} else {
@@ -91,11 +92,15 @@ static inline void pic_set_irq1(struct kvm_kpic_state *s, int irq, int level)
}
else /* edge triggered */
if (level) {
- if ((s->last_irr & mask) == 0)
+ if ((s->last_irr & mask) == 0) {
+ ret = !(s->irr & mask);
s->irr |= mask;
+ }
s->last_irr |= mask;
} else
s->last_irr &= ~mask;
+
+ return (s->imr & mask) ? -1 : ret;
}
/*
@@ -172,16 +177,19 @@ void kvm_pic_update_irq(struct kvm_pic *s)
pic_unlock(s);
}
-void kvm_pic_set_irq(void *opaque, int irq, int level)
+int kvm_pic_set_irq(void *opaque, int irq, int level)
{
struct kvm_pic *s = opaque;
+ int ret = -1;
pic_lock(s);
if (irq >= 0 && irq < PIC_NUM_PINS) {
- pic_set_irq1(&s->pics[irq >> 3], irq & 7, level);
+ ret = pic_set_irq1(&s->pics[irq >> 3], irq & 7, level);
pic_update_irq(s);
}
pic_unlock(s);
+
+ return ret;
}
/*