1
linux/arch/x86/kvm/irq.h
Marcelo Tosatti 3d80840d96 KVM: hlt emulation should take in-kernel APIC/PIT timers into account
Timers that fire between guest hlt and vcpu_block's add_wait_queue() are
ignored, possibly resulting in hangs.

Also make sure that atomic_inc and waitqueue_active tests happen in the
specified order, otherwise the following race is open:

CPU0                                        CPU1
                                            if (waitqueue_active(wq))
add_wait_queue()
if (!atomic_read(pit_timer->pending))
    schedule()
                                            atomic_inc(pit_timer->pending)

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 12:04:11 +03:00

92 lines
2.5 KiB
C

/*
* irq.h: in kernel interrupt controller related definitions
* Copyright (c) 2007, Intel Corporation.
*
* 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>
*
*/
#ifndef __IRQ_H
#define __IRQ_H
#include <linux/mm_types.h>
#include <linux/hrtimer.h>
#include <linux/kvm_host.h>
#include "iodev.h"
#include "ioapic.h"
#include "lapic.h"
struct kvm;
struct kvm_vcpu;
typedef void irq_request_func(void *opaque, int level);
struct kvm_kpic_state {
u8 last_irr; /* edge detection */
u8 irr; /* interrupt request register */
u8 imr; /* interrupt mask register */
u8 isr; /* interrupt service register */
u8 priority_add; /* highest irq priority */
u8 irq_base;
u8 read_reg_select;
u8 poll;
u8 special_mask;
u8 init_state;
u8 auto_eoi;
u8 rotate_on_auto_eoi;
u8 special_fully_nested_mode;
u8 init4; /* true if 4 byte init */
u8 elcr; /* PIIX edge/trigger selection */
u8 elcr_mask;
struct kvm_pic *pics_state;
};
struct kvm_pic {
struct kvm_kpic_state pics[2]; /* 0 is master pic, 1 is slave pic */
irq_request_func *irq_request;
void *irq_request_opaque;
int output; /* intr from master PIC */
struct kvm_io_device dev;
};
struct kvm_pic *kvm_create_pic(struct kvm *kvm);
void kvm_pic_set_irq(void *opaque, int irq, int level);
int kvm_pic_read_irq(struct kvm_pic *s);
void kvm_pic_update_irq(struct kvm_pic *s);
static inline struct kvm_pic *pic_irqchip(struct kvm *kvm)
{
return kvm->arch.vpic;
}
static inline int irqchip_in_kernel(struct kvm *kvm)
{
return pic_irqchip(kvm) != NULL;
}
void kvm_pic_reset(struct kvm_kpic_state *s);
void kvm_timer_intr_post(struct kvm_vcpu *vcpu, int vec);
void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu);
void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu);
void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu);
int pit_has_pending_timer(struct kvm_vcpu *vcpu);
int apic_has_pending_timer(struct kvm_vcpu *vcpu);
#endif