On Wed, Jun 28, 2017 at 12:37:04PM -0300, Eduardo Habkost wrote:
> On Wed, Jun 28, 2017 at 03:15:44PM +0800, Peter Xu wrote:
> > It'll be strange that the migration object inherits TYPE_DEVICE. Add
> > some explanations to it.
> >
> > Signed-off-by: Peter Xu <pet...@redhat.com>
> > ---
> > migration/migration.c | 8 ++++++++
> > 1 file changed, 8 insertions(+)
> >
> > diff --git a/migration/migration.c b/migration/migration.c
> > index b1b0825..2398a9d 100644
> > --- a/migration/migration.c
> > +++ b/migration/migration.c
> > @@ -2046,6 +2046,14 @@ static void migration_instance_init(Object *obj)
> >
> > static const TypeInfo migration_type = {
> > .name = TYPE_MIGRATION,
> > + /*
> > + * NOTE: "migration" itself is not really a device. We used
>
> I suggest extending this as:
>
> TYPE_MIGRATION is not really a device, as the object is not created
> using qdev_create(), it is not attached to the qdev device tree, and
> it is never realized.
>
>
> > + * TYPE_DEVICE here only to leverage some existing QDev features
> > + * like "-global" properties, and HW_COMPAT_* fields (which are
> > + * finally applied as global properties as well). If one day the
> > + * global property feature can be migrated from QDev to QObject in
> > + * general, then we can switch to QObject as well.
> > + */
>
> QOM objects (qom/object.h) are not QObject (qapi/qmp/qobject.h). People
> often confuse them with each other. (It probably doesn't help that both
> are described as "QEMU Object Model" at their headers.)
Indeed. Sorry I got confused.
>
> I suggest rewriting it as:
>
> If one day we allow non-device QOM objects to use the global property
> system, we can switch this from TYPE_DEVICE to TYPE_OBJECT."
For the comment for this patch (and patch 10 on "properties" and
"globals"), I both agree. Again, I'll see what's the best way to fix
them. Thanks,
--
Peter Xu
