Re: [Qemu-devel] [RFC PATCH 02/12] migration: migrate icount fields.

[Frederic Konrad]

On 22/03/2014 09:57, Paolo Bonzini wrote:
> Il 21/03/2014 20:17, address@hidden ha scritto:
> > From: KONRAD Frederic <address@hidden>
> >
> > This fixes a bug where qemu_icount and qemu_icount_bias are not 
> > migrated.
> >
> > Signed-off-by: KONRAD Frederic <address@hidden>
> > ---
> >  cpus.c | 23 ++++++++++++++++++++++-
> >  1 file changed, 22 insertions(+), 1 deletion(-)
> >
> > diff --git a/cpus.c b/cpus.c
> > index 687717f..bdbc431 100644
> > --- a/cpus.c
> > +++ b/cpus.c
> > @@ -440,12 +440,33 @@ static const VMStateDescription vmstate_timers = {
> >      }
> >  };
> >
> > +/*
> > + * This is used instead of vmstate_timers when icount is used.
> > + * cpu_ticks_offset and dummy fields are unused in icount mode so we 
> > can replace
> > + * them with icount variables.
> > + */
> > +static const VMStateDescription icount_vmstate_timers = {
> > +    .name = "timer",
> > +    .version_id = 2,
> > +    .minimum_version_id = 1,
> > +    .minimum_version_id_old = 1,
> > +    .fields      = (VMStateField[]) {
> > +        VMSTATE_INT64(qemu_icount_bias, TimersState),
> > +        VMSTATE_INT64(qemu_icount, TimersState),
> > +        VMSTATE_INT64_V(cpu_clock_offset, TimersState, 2),
> > +        VMSTATE_END_OF_LIST()
> > +    }
> > +};
> > +
> >  void configure_icount(const char *option)
> >  {
> >      seqlock_init(&timers_state.vm_clock_seqlock, NULL);
> > -    vmstate_register(NULL, 0, &vmstate_timers, &timers_state);
> > +
> >      if (!option) {
> > +        vmstate_register(NULL, 0, &vmstate_timers, &timers_state);
> >          return;
> > +    } else {
> > +        vmstate_register(NULL, 0, &icount_vmstate_timers, 
> > &timers_state);
> >      }
> >
> >      icount_warp_timer = timer_new_ns(QEMU_CLOCK_REALTIME,
>
> You can also use a subsection for this.
>
> Paolo

Hi Paolo,
Thanks for review!

Did you mean something like that:

--- a/cpus.c
+++ b/cpus.c
@@ -427,6 +427,26 @@ void qemu_clock_warp(QEMUClockType type)
     }
 }

+static bool icount_state_needed(void *opaque)
+{
+    return (use_icount != 0);
+}
+
+/*
+ * This is a subsection for icount migration.
+ */
+static const VMStateDescription icount_vmstate_timers = {
+    .name = "icount",
+    .version_id = 2,
+    .minimum_version_id = 1,
+    .minimum_version_id_old = 1,
+    .fields      = (VMStateField[]) {
+        VMSTATE_INT64(qemu_icount_bias, TimersState),
+        VMSTATE_INT64(qemu_icount, TimersState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
 static const VMStateDescription vmstate_timers = {
     .name = "timer",
     .version_id = 2,
@@ -437,6 +457,14 @@ static const VMStateDescription vmstate_timers = {
         VMSTATE_INT64(dummy, TimersState),
         VMSTATE_INT64_V(cpu_clock_offset, TimersState, 2),
         VMSTATE_END_OF_LIST()
+    },
+    .subsections = (VMStateSubsection[]) {
+        {
+            .vmsd = &icount_vmstate_timers,
+            .needed = icount_state_needed,
+        }, {
+            /* empty */
+        }
     }
 };

Thanks,
Fred