Re: [Qemu-devel] [PATCH 4/9] object: remove object_finalize

["Andreas Färber" <afaerber@suse.de>]

Am 26.08.2012 17:51, schrieb Anthony Liguori:
> Callers should just use object_unref
> 
> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
> ---
>  hw/qdev.c             |    4 ----
>  include/qemu/object.h |    9 ---------
>  qom/object.c          |    2 +-
>  3 files changed, 1 insertions(+), 14 deletions(-)
> 
> diff --git a/hw/qdev.c b/hw/qdev.c
> index 6b61daa..fdee91f 100644
> --- a/hw/qdev.c
> +++ b/hw/qdev.c
> @@ -678,13 +678,9 @@ static void device_initfn(Object *obj)
>  static void device_finalize(Object *obj)
>  {
>      DeviceState *dev = DEVICE(obj);
> -    BusState *bus;
>      DeviceClass *dc = DEVICE_GET_CLASS(dev);
>  
>      if (dev->state == DEV_STATE_INITIALIZED) {
> -        while (dev->num_child_bus) {
> -            bus = QLIST_FIRST(&dev->child_bus);
> -        }
>          if (qdev_get_vmsd(dev)) {
>              vmstate_unregister(dev, qdev_get_vmsd(dev), dev);
>          }

This seems to answer my remark on 3/9, should've been squashed into that
one.

> diff --git a/include/qemu/object.h b/include/qemu/object.h
> index 487adcd..8bc9935 100644
> --- a/include/qemu/object.h
> +++ b/include/qemu/object.h
> @@ -490,15 +490,6 @@ void object_initialize_with_type(void *data, Type type);
>  void object_initialize(void *obj, const char *typename);
>  
>  /**
> - * object_finalize:
> - * @obj: The object to finalize.
> - *
> - * This function destroys and object without freeing the memory associated with
> - * it.
> - */
> -void object_finalize(void *obj);
> -
> -/**
>   * object_dynamic_cast:
>   * @obj: The object to cast.
>   * @typename: The @typename to cast to.
> diff --git a/qom/object.c b/qom/object.c
> index 44135c3..1144f79 100644
> --- a/qom/object.c
> +++ b/qom/object.c
> @@ -375,7 +375,7 @@ static void object_deinit(Object *obj, TypeImpl *type)
>      }
>  }
>  
> -void object_finalize(void *data)
> +static void object_finalize(void *data)
>  {
>      Object *obj = data;
>      TypeImpl *ti = obj->class->type;

This is what I was referring to with breaking the encapsulation on 3/9:
When we have a PHB with embedded PCIDevice on its PCIBus, as
demonstrated with i440fx and prep_pci, then when doing object_delete()
on the whole thing I expect the main object's finalizer to call
object_finalize() on its embedded childs, forcing their uninit or an
assert if a programming error. Not just an unref that might or might not
finalize it.

If however finalize is called only at refcount 0 then who will unref the
self-created children? Finalize would never be called due to pending
references by its children...

Andreas

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