KVM: x86: Kick VCPU outside PIC lock again

This restores the deferred VCPU kicking before 956f97cf. We need this
over -rt as wake_up* requires non-atomic context in this configuration.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Jan Kiszka 2010-02-24 10:41:58 +01:00 committed by Avi Kivity
parent a595405df9
commit 50a085bdd4
2 changed files with 39 additions and 15 deletions

View File

@ -33,6 +33,29 @@
#include <linux/kvm_host.h>
#include "trace.h"
static void pic_lock(struct kvm_pic *s)
__acquires(&s->lock)
{
raw_spin_lock(&s->lock);
}
static void pic_unlock(struct kvm_pic *s)
__releases(&s->lock)
{
bool wakeup = s->wakeup_needed;
struct kvm_vcpu *vcpu;
s->wakeup_needed = false;
raw_spin_unlock(&s->lock);
if (wakeup) {
vcpu = s->kvm->bsp_vcpu;
if (vcpu)
kvm_vcpu_kick(vcpu);
}
}
static void pic_clear_isr(struct kvm_kpic_state *s, int irq)
{
s->isr &= ~(1 << irq);
@ -45,19 +68,19 @@ static void pic_clear_isr(struct kvm_kpic_state *s, int irq)
* 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.
*/
raw_spin_unlock(&s->pics_state->lock);
pic_unlock(s->pics_state);
kvm_notify_acked_irq(s->pics_state->kvm, SELECT_PIC(irq), irq);
raw_spin_lock(&s->pics_state->lock);
pic_lock(s->pics_state);
}
void kvm_pic_clear_isr_ack(struct kvm *kvm)
{
struct kvm_pic *s = pic_irqchip(kvm);
raw_spin_lock(&s->lock);
pic_lock(s);
s->pics[0].isr_ack = 0xff;
s->pics[1].isr_ack = 0xff;
raw_spin_unlock(&s->lock);
pic_unlock(s);
}
/*
@ -158,9 +181,9 @@ static void pic_update_irq(struct kvm_pic *s)
void kvm_pic_update_irq(struct kvm_pic *s)
{
raw_spin_lock(&s->lock);
pic_lock(s);
pic_update_irq(s);
raw_spin_unlock(&s->lock);
pic_unlock(s);
}
int kvm_pic_set_irq(void *opaque, int irq, int level)
@ -168,14 +191,14 @@ int kvm_pic_set_irq(void *opaque, int irq, int level)
struct kvm_pic *s = opaque;
int ret = -1;
raw_spin_lock(&s->lock);
pic_lock(s);
if (irq >= 0 && irq < PIC_NUM_PINS) {
ret = pic_set_irq1(&s->pics[irq >> 3], irq & 7, level);
pic_update_irq(s);
trace_kvm_pic_set_irq(irq >> 3, irq & 7, s->pics[irq >> 3].elcr,
s->pics[irq >> 3].imr, ret == 0);
}
raw_spin_unlock(&s->lock);
pic_unlock(s);
return ret;
}
@ -205,7 +228,7 @@ int kvm_pic_read_irq(struct kvm *kvm)
int irq, irq2, intno;
struct kvm_pic *s = pic_irqchip(kvm);
raw_spin_lock(&s->lock);
pic_lock(s);
irq = pic_get_irq(&s->pics[0]);
if (irq >= 0) {
pic_intack(&s->pics[0], irq);
@ -230,7 +253,7 @@ int kvm_pic_read_irq(struct kvm *kvm)
intno = s->pics[0].irq_base + irq;
}
pic_update_irq(s);
raw_spin_unlock(&s->lock);
pic_unlock(s);
return intno;
}
@ -444,7 +467,7 @@ static int picdev_write(struct kvm_io_device *this,
printk(KERN_ERR "PIC: non byte write\n");
return 0;
}
raw_spin_lock(&s->lock);
pic_lock(s);
switch (addr) {
case 0x20:
case 0x21:
@ -457,7 +480,7 @@ static int picdev_write(struct kvm_io_device *this,
elcr_ioport_write(&s->pics[addr & 1], addr, data);
break;
}
raw_spin_unlock(&s->lock);
pic_unlock(s);
return 0;
}
@ -474,7 +497,7 @@ static int picdev_read(struct kvm_io_device *this,
printk(KERN_ERR "PIC: non byte read\n");
return 0;
}
raw_spin_lock(&s->lock);
pic_lock(s);
switch (addr) {
case 0x20:
case 0x21:
@ -488,7 +511,7 @@ static int picdev_read(struct kvm_io_device *this,
break;
}
*(unsigned char *)val = data;
raw_spin_unlock(&s->lock);
pic_unlock(s);
return 0;
}
@ -505,7 +528,7 @@ static void pic_irq_request(void *opaque, int level)
s->output = level;
if (vcpu && level && (s->pics[0].isr_ack & (1 << irq))) {
s->pics[0].isr_ack &= ~(1 << irq);
kvm_vcpu_kick(vcpu);
s->wakeup_needed = true;
}
}

View File

@ -63,6 +63,7 @@ struct kvm_kpic_state {
struct kvm_pic {
raw_spinlock_t lock;
bool wakeup_needed;
unsigned pending_acks;
struct kvm *kvm;
struct kvm_kpic_state pics[2]; /* 0 is master pic, 1 is slave pic */