Commit 0ec329da authored by Jan Kiszka's avatar Jan Kiszka Committed by Marcelo Tosatti
Browse files

kvm: x86: Introduce kvmclock device to save/restore its state 



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: default avatarJan Kiszka <jan.kiszka@siemens.com>
CC: Glauber Costa <glommer@redhat.com>
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
parent 6a7af8cb

Makefile.target

+2 −2
Original line number Diff line number Diff line
@@ -37,7 +37,7 @@ ifndef CONFIG_HAIKU 
LIBS+=-lm

endif



kvm.o kvm-all.o vhost.o vhost_net.o: QEMU_CFLAGS+=$(KVM_CFLAGS)

kvm.o kvm-all.o vhost.o vhost_net.o kvmclock.o: QEMU_CFLAGS+=$(KVM_CFLAGS)



config-target.h: config-target.h-timestamp

config-target.h-timestamp: config-target.mak
@@ -218,7 +218,7 @@ obj-i386-y += cirrus_vga.o apic.o ioapic.o piix_pci.o 
obj-i386-y += vmport.o applesmc.o

obj-i386-y += device-hotplug.o pci-hotplug.o smbios.o wdt_ib700.o

obj-i386-y += debugcon.o multiboot.o

obj-i386-y += pc_piix.o

obj-i386-y += pc_piix.o kvmclock.o

obj-i386-$(CONFIG_SPICE) += qxl.o qxl-logger.o qxl-render.o



# shared objects

hw/kvmclock.c

0 → 100644
+125 −0
Original line number Diff line number Diff line 
/*

 * 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) */

hw/kvmclock.h

0 → 100644
+14 −0
Original line number Diff line number Diff line 
/*

 * 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.

 *

 */



void kvmclock_create(void);

hw/pc_piix.c

+25 −7
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ 
#include "boards.h"

#include "ide.h"

#include "kvm.h"

#include "kvmclock.h"

#include "sysemu.h"

#include "sysbus.h"

#include "arch_init.h"
@@ -66,7 +67,8 @@ static void pc_init1(ram_addr_t ram_size, 
                     const char *kernel_cmdline,

                     const char *initrd_filename,

                     const char *cpu_model,

                     int pci_enabled)

                     int pci_enabled,

                     int kvmclock_enabled)

{

    int i;

    ram_addr_t below_4g_mem_size, above_4g_mem_size;
@@ -86,6 +88,10 @@ static void pc_init1(ram_addr_t ram_size, 


    pc_cpus_init(cpu_model);



    if (kvmclock_enabled) {

        kvmclock_create();

    }



    /* allocate ram and load rom/bios */

    pc_memory_init(ram_size, kernel_filename, kernel_cmdline, initrd_filename,

                   &below_4g_mem_size, &above_4g_mem_size);
@@ -193,7 +199,19 @@ static void pc_init_pci(ram_addr_t ram_size, 
{

    pc_init1(ram_size, boot_device,

             kernel_filename, kernel_cmdline,

             initrd_filename, cpu_model, 1);

             initrd_filename, cpu_model, 1, 1);

}



static void pc_init_pci_no_kvmclock(ram_addr_t ram_size,

                                    const char *boot_device,

                                    const char *kernel_filename,

                                    const char *kernel_cmdline,

                                    const char *initrd_filename,

                                    const char *cpu_model)

{

    pc_init1(ram_size, boot_device,

             kernel_filename, kernel_cmdline,

             initrd_filename, cpu_model, 1, 0);

}



static void pc_init_isa(ram_addr_t ram_size,
@@ -207,7 +225,7 @@ static void pc_init_isa(ram_addr_t ram_size, 
        cpu_model = "486";

    pc_init1(ram_size, boot_device,

             kernel_filename, kernel_cmdline,

             initrd_filename, cpu_model, 0);

             initrd_filename, cpu_model, 0, 1);

}



static QEMUMachine pc_machine = {
@@ -222,7 +240,7 @@ static QEMUMachine pc_machine = { 
static QEMUMachine pc_machine_v0_13 = {

    .name = "pc-0.13",

    .desc = "Standard PC",

    .init = pc_init_pci,

    .init = pc_init_pci_no_kvmclock,

    .max_cpus = 255,

    .compat_props = (GlobalProperty[]) {

        {
@@ -249,7 +267,7 @@ static QEMUMachine pc_machine_v0_13 = { 
static QEMUMachine pc_machine_v0_12 = {

    .name = "pc-0.12",

    .desc = "Standard PC",

    .init = pc_init_pci,

    .init = pc_init_pci_no_kvmclock,

    .max_cpus = 255,

    .compat_props = (GlobalProperty[]) {

        {
@@ -280,7 +298,7 @@ static QEMUMachine pc_machine_v0_12 = { 
static QEMUMachine pc_machine_v0_11 = {

    .name = "pc-0.11",

    .desc = "Standard PC, qemu 0.11",

    .init = pc_init_pci,

    .init = pc_init_pci_no_kvmclock,

    .max_cpus = 255,

    .compat_props = (GlobalProperty[]) {

        {
@@ -319,7 +337,7 @@ static QEMUMachine pc_machine_v0_11 = { 
static QEMUMachine pc_machine_v0_10 = {

    .name = "pc-0.10",

    .desc = "Standard PC, qemu 0.10",

    .init = pc_init_pci,

    .init = pc_init_pci_no_kvmclock,

    .max_cpus = 255,

    .compat_props = (GlobalProperty[]) {

        {