mirror of
https://github.com/xemu-project/xemu.git
synced 2024-12-02 16:46:59 +00:00
0ec329dab9
If kvmclock is used, which implies the kernel supports it, register a kvmclock device with the sysbus. Its main purpose is to save and restore the kernel state on migration, but this will also allow to visualize it one day. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> CC: Glauber Costa <glommer@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
126 lines
2.9 KiB
C
126 lines
2.9 KiB
C
/*
|
|
* QEMU KVM support, paravirtual clock device
|
|
*
|
|
* Copyright (C) 2011 Siemens AG
|
|
*
|
|
* Authors:
|
|
* Jan Kiszka <jan.kiszka@siemens.com>
|
|
*
|
|
* This work is licensed under the terms of the GNU GPL version 2.
|
|
* See the COPYING file in the top-level directory.
|
|
*
|
|
*/
|
|
|
|
#include "qemu-common.h"
|
|
#include "sysemu.h"
|
|
#include "sysbus.h"
|
|
#include "kvm.h"
|
|
#include "kvmclock.h"
|
|
|
|
#if defined(CONFIG_KVM_PARA) && defined(KVM_CAP_ADJUST_CLOCK)
|
|
|
|
#include <linux/kvm.h>
|
|
#include <linux/kvm_para.h>
|
|
|
|
typedef struct KVMClockState {
|
|
SysBusDevice busdev;
|
|
uint64_t clock;
|
|
bool clock_valid;
|
|
} KVMClockState;
|
|
|
|
static void kvmclock_pre_save(void *opaque)
|
|
{
|
|
KVMClockState *s = opaque;
|
|
struct kvm_clock_data data;
|
|
int ret;
|
|
|
|
if (s->clock_valid) {
|
|
return;
|
|
}
|
|
ret = kvm_vm_ioctl(kvm_state, KVM_GET_CLOCK, &data);
|
|
if (ret < 0) {
|
|
fprintf(stderr, "KVM_GET_CLOCK failed: %s\n", strerror(ret));
|
|
data.clock = 0;
|
|
}
|
|
s->clock = data.clock;
|
|
/*
|
|
* If the VM is stopped, declare the clock state valid to avoid re-reading
|
|
* it on next vmsave (which would return a different value). Will be reset
|
|
* when the VM is continued.
|
|
*/
|
|
s->clock_valid = !vm_running;
|
|
}
|
|
|
|
static int kvmclock_post_load(void *opaque, int version_id)
|
|
{
|
|
KVMClockState *s = opaque;
|
|
struct kvm_clock_data data;
|
|
|
|
data.clock = s->clock;
|
|
data.flags = 0;
|
|
return kvm_vm_ioctl(kvm_state, KVM_SET_CLOCK, &data);
|
|
}
|
|
|
|
static void kvmclock_vm_state_change(void *opaque, int running, int reason)
|
|
{
|
|
KVMClockState *s = opaque;
|
|
|
|
if (running) {
|
|
s->clock_valid = false;
|
|
}
|
|
}
|
|
|
|
static int kvmclock_init(SysBusDevice *dev)
|
|
{
|
|
KVMClockState *s = FROM_SYSBUS(KVMClockState, dev);
|
|
|
|
qemu_add_vm_change_state_handler(kvmclock_vm_state_change, s);
|
|
return 0;
|
|
}
|
|
|
|
static const VMStateDescription kvmclock_vmsd = {
|
|
.name = "kvmclock",
|
|
.version_id = 1,
|
|
.minimum_version_id = 1,
|
|
.minimum_version_id_old = 1,
|
|
.pre_save = kvmclock_pre_save,
|
|
.post_load = kvmclock_post_load,
|
|
.fields = (VMStateField[]) {
|
|
VMSTATE_UINT64(clock, KVMClockState),
|
|
VMSTATE_END_OF_LIST()
|
|
}
|
|
};
|
|
|
|
static SysBusDeviceInfo kvmclock_info = {
|
|
.qdev.name = "kvmclock",
|
|
.qdev.size = sizeof(KVMClockState),
|
|
.qdev.vmsd = &kvmclock_vmsd,
|
|
.qdev.no_user = 1,
|
|
.init = kvmclock_init,
|
|
};
|
|
|
|
/* Note: Must be called after VCPU initialization. */
|
|
void kvmclock_create(void)
|
|
{
|
|
if (kvm_enabled() &&
|
|
first_cpu->cpuid_kvm_features & (1ULL << KVM_FEATURE_CLOCKSOURCE)) {
|
|
sysbus_create_simple("kvmclock", -1, NULL);
|
|
}
|
|
}
|
|
|
|
static void kvmclock_register_device(void)
|
|
{
|
|
if (kvm_enabled()) {
|
|
sysbus_register_withprop(&kvmclock_info);
|
|
}
|
|
}
|
|
|
|
device_init(kvmclock_register_device);
|
|
|
|
#else /* !(CONFIG_KVM_PARA && KVM_CAP_ADJUST_CLOCK) */
|
|
|
|
void kvmclock_create(void)
|
|
{
|
|
}
|
|
#endif /* !(CONFIG_KVM_PARA && KVM_CAP_ADJUST_CLOCK) */
|