linux_dsm_epyc7002/arch/x86/kvm/irq.c
Chris Lalancette 33572ac0ad KVM: x86: Introduce a workqueue to deliver PIT timer interrupts
We really want to "kvm_set_irq" during the hrtimer callback,
but that is risky because that is during interrupt context.
Instead, offload the work to a workqueue, which is a bit safer
and should provide most of the same functionality.

Signed-off-by: Chris Lalancette <clalance@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01 10:46:49 +03:00

102 lines
2.4 KiB
C

/*
* irq.c: API for in kernel interrupt controller
* Copyright (c) 2007, Intel Corporation.
* Copyright 2009 Red Hat, Inc. and/or its affilates.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc., 59 Temple
* Place - Suite 330, Boston, MA 02111-1307 USA.
* Authors:
* Yaozu (Eddie) Dong <Eddie.dong@intel.com>
*
*/
#include <linux/module.h>
#include <linux/kvm_host.h>
#include "irq.h"
#include "i8254.h"
#include "x86.h"
/*
* check if there are pending timer events
* to be processed.
*/
int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
{
int ret;
ret = pit_has_pending_timer(vcpu);
ret |= apic_has_pending_timer(vcpu);
return ret;
}
EXPORT_SYMBOL(kvm_cpu_has_pending_timer);
/*
* check if there is pending interrupt without
* intack.
*/
int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
{
struct kvm_pic *s;
if (!irqchip_in_kernel(v->kvm))
return v->arch.interrupt.pending;
if (kvm_apic_has_interrupt(v) == -1) { /* LAPIC */
if (kvm_apic_accept_pic_intr(v)) {
s = pic_irqchip(v->kvm); /* PIC */
return s->output;
} else
return 0;
}
return 1;
}
EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt);
/*
* Read pending interrupt vector and intack.
*/
int kvm_cpu_get_interrupt(struct kvm_vcpu *v)
{
struct kvm_pic *s;
int vector;
if (!irqchip_in_kernel(v->kvm))
return v->arch.interrupt.nr;
vector = kvm_get_apic_interrupt(v); /* APIC */
if (vector == -1) {
if (kvm_apic_accept_pic_intr(v)) {
s = pic_irqchip(v->kvm);
s->output = 0; /* PIC */
vector = kvm_pic_read_irq(v->kvm);
}
}
return vector;
}
EXPORT_SYMBOL_GPL(kvm_cpu_get_interrupt);
void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu)
{
kvm_inject_apic_timer_irqs(vcpu);
/* TODO: PIT, RTC etc. */
}
EXPORT_SYMBOL_GPL(kvm_inject_pending_timer_irqs);
void __kvm_migrate_timers(struct kvm_vcpu *vcpu)
{
__kvm_migrate_apic_timer(vcpu);
__kvm_migrate_pit_timer(vcpu);
}