Re: [Qemu-devel] [PATCH v3 1/3] target-i386: add a subsection for migrating vcpu's TSC rate

[Haozhong Zhang]

On 11/11/15 12:16, Eduardo Habkost wrote:
> On Mon, Nov 02, 2015 at 05:26:41PM +0800, Haozhong Zhang wrote:
> > A new subsection 'vmstate_tsc_khz' is added to migrate vcpu's TSC
> > rate. For the backwards compatibility, this subsection is not migrated
> > on pc-*-2.4 and older machine types.
> > 
> > Signed-off-by: Haozhong Zhang <address@hidden>
> > ---
> >  hw/i386/pc.c          |  1 +
> >  hw/i386/pc_piix.c     |  1 +
> >  hw/i386/pc_q35.c      |  1 +
> >  include/hw/i386/pc.h  |  1 +
> >  target-i386/cpu.h     |  1 +
> >  target-i386/machine.c | 21 +++++++++++++++++++++
> >  6 files changed, 26 insertions(+)
> > 
> > diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> > index 0cb8afd..2f2fc93 100644
> > --- a/hw/i386/pc.c
> > +++ b/hw/i386/pc.c
> > @@ -1952,6 +1952,7 @@ static void pc_machine_class_init(ObjectClass *oc, 
> > void *data)
> >      HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(oc);
> >  
> >      pcmc->get_hotplug_handler = mc->get_hotplug_handler;
> > +    pcmc->save_tsc_khz = true;
> >      mc->get_hotplug_handler = pc_get_hotpug_handler;
> >      mc->cpu_index_to_socket_id = pc_cpu_index_to_socket_id;
> >      mc->default_boot_order = "cad";
> > diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
> > index 393dcc4..fc71321 100644
> > --- a/hw/i386/pc_piix.c
> > +++ b/hw/i386/pc_piix.c
> > @@ -487,6 +487,7 @@ static void pc_i440fx_2_4_machine_options(MachineClass 
> > *m)
> >      m->alias = NULL;
> >      m->is_default = 0;
> >      pcmc->broken_reserved_end = true;
> > +    pcmc->save_tsc_khz = false;
> >      SET_MACHINE_COMPAT(m, PC_COMPAT_2_4);
> >  }
> >  
> > diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
> > index 2f8f396..858ed69 100644
> > --- a/hw/i386/pc_q35.c
> > +++ b/hw/i386/pc_q35.c
> > @@ -385,6 +385,7 @@ static void pc_q35_2_4_machine_options(MachineClass *m)
> >      pc_q35_2_5_machine_options(m);
> >      m->alias = NULL;
> >      pcmc->broken_reserved_end = true;
> > +    pcmc->save_tsc_khz = false;
> 
> I had suggested the PCMachineClass field, but now I've been thinking:
> all other fields related to tsc_khz are in X86CPU, so I believe this
> belongs to X86CPU too. It could be a simple X86CPU property set by
> PC_COMPAT_2_4.
>

Reasonable, will update in the next version.

Thanks,
Haozhong

> -- 
> Eduardo