Message ID | 4F3D3F26.8010402@mentor.com |
---|---|
State | New |
Headers | show |
Object model lifecycle changes aren't trivial IMHO. [no comment on actual patch contents implied] -- PMM On 16 February 2012 17:38, Alexander Barabash <alexander_barabash@mentor.com> wrote: > > Replace object_delete() with object_unref(). > > In the existing implementation, object_delete() > calls object_unref(), then frees the object's storage. > Running object_delete() on an object with reference count > different from one (1) causes program failure. > > In the existing implementation, object_unref() > finalizes the object when its reference count becomes zero (0). > > In the new implementation, object_unref() > finalizes and frees the object's storage when the reference count becomes > zero (0). > > One usage of object_delete() replaced by object_unref(). > > Signed-off-by: Alexander Barabash <alexander_barabash@mentor.com> > > diff --git a/hw/qdev.c b/hw/qdev.c > index f0eb3a7..891981a 100644 > --- a/hw/qdev.c > +++ b/hw/qdev.c > @@ -247,7 +247,7 @@ void qdev_init_nofail(DeviceState *dev) > /* Unlink device from bus and free the structure. */ > void qdev_free(DeviceState *dev) > { > - object_delete(OBJECT(dev)); > + object_unref(OBJECT(dev)); > } > > void qdev_machine_creation_done(void) > diff --git a/include/qemu/object.h b/include/qemu/object.h > index 69cc2ab..e7e32fe 100644 > --- a/include/qemu/object.h > +++ b/include/qemu/object.h > @@ -415,8 +415,9 @@ struct InterfaceInfo > * object_new: > * @typename: The name of the type of the object to instantiate. > * > - * This function will initialize a new object using heap allocated memory. > This > - * function should be paired with object_delete() to free the resources > + * This function will initialize a new object using heap allocated memory. > + * The object's reference count will be set to one (1) upon successful > completion. > + * This function should be paired with object_unref() to free the resources > * associated with the object. > * > * Returns: The newly allocated and instantiated object. > @@ -427,8 +428,9 @@ Object *object_new(const char *typename); > * object_new_with_type: > * @type: The type of the object to instantiate. > * > - * This function will initialize a new object using heap allocated memory. > This > - * function should be paired with object_delete() to free the resources > + * This function will initialize a new object using heap allocated memory. > + * The object's reference count will be set to one (1) upon successful > completion. > + * This function should be paired with object_unref() to free the resources > * associated with the object. > * > * Returns: The newly allocated and instantiated object. > @@ -436,15 +438,6 @@ Object *object_new(const char *typename); > Object *object_new_with_type(Type type); > > /** > - * object_delete: > - * @obj: The object to free. > - * > - * Finalize an object and then free the memory associated with it. This > should > - * be paired with object_new() to free the resources associated with an > object. > - */ > -void object_delete(Object *obj); > - > -/** > * object_initialize_with_type: > * @obj: A pointer to the memory to be used for the object. > * @type: The type of the object to instantiate. > @@ -573,8 +566,10 @@ void object_ref(Object *obj); > * qdef_unref: > * @obj: the object > * > - * Decrease the reference count of a object. A object cannot be freed as > long > + * Decrease the reference count of a object. A object is not freed as long > * as its reference count is greater than zero. > + * Once an object's reference count gets to zero (0), > + * the object is finalized and the memory associated with it is freed. > */ > void object_unref(Object *obj); > > diff --git a/qom/object.c b/qom/object.c > index 0cbd9bb..2de6eaf 100644 > --- a/qom/object.c > +++ b/qom/object.c > @@ -328,7 +328,7 @@ static void object_deinit(Object *obj, TypeImpl *type) > while (obj->interfaces) { > Interface *iface_obj = obj->interfaces->data; > obj->interfaces = g_slist_delete_link(obj->interfaces, > obj->interfaces); > - object_delete(OBJECT(iface_obj)); > + object_unref(OBJECT(iface_obj)); > } > > if (type_has_parent(type)) { > @@ -369,13 +369,6 @@ Object *object_new(const char *typename) > return object_new_with_type(ti); > } > > -void object_delete(Object *obj) > -{ > - object_unref(obj); > - g_assert(obj->ref == 0); > - g_free(obj); > -} > - > static bool type_is_ancestor(TypeImpl *type, TypeImpl *target_type) > { > assert(target_type); > @@ -583,6 +576,7 @@ void object_unref(Object *obj) > /* parent always holds a reference to its children */ > if (obj->ref == 0) { > object_finalize(obj); > + g_free(obj); > } > } > > >
On Thu, Feb 16, 2012 at 6:12 PM, Peter Maydell <peter.maydell@linaro.org> wrote: > Object model lifecycle changes aren't trivial IMHO. > [no comment on actual patch contents implied] Agreed. Stefan
diff --git a/hw/qdev.c b/hw/qdev.c index f0eb3a7..891981a 100644 --- a/hw/qdev.c +++ b/hw/qdev.c @@ -247,7 +247,7 @@ void qdev_init_nofail(DeviceState *dev) /* Unlink device from bus and free the structure. */ void qdev_free(DeviceState *dev) { - object_delete(OBJECT(dev)); + object_unref(OBJECT(dev)); } void qdev_machine_creation_done(void) diff --git a/include/qemu/object.h b/include/qemu/object.h index 69cc2ab..e7e32fe 100644 --- a/include/qemu/object.h +++ b/include/qemu/object.h @@ -415,8 +415,9 @@ struct InterfaceInfo * object_new: * @typename: The name of the type of the object to instantiate. * - * This function will initialize a new object using heap allocated memory. This - * function should be paired with object_delete() to free the resources + * This function will initialize a new object using heap allocated memory. + * The object's reference count will be set to one (1) upon successful completion. + * This function should be paired with object_unref() to free the resources * associated with the object. * * Returns: The newly allocated and instantiated object. @@ -427,8 +428,9 @@ Object *object_new(const char *typename); * object_new_with_type: * @type: The type of the object to instantiate. * - * This function will initialize a new object using heap allocated memory. This - * function should be paired with object_delete() to free the resources + * This function will initialize a new object using heap allocated memory. + * The object's reference count will be set to one (1) upon successful completion. + * This function should be paired with object_unref() to free the resources * associated with the object. * * Returns: The newly allocated and instantiated object. @@ -436,15 +438,6 @@ Object *object_new(const char *typename); Object *object_new_with_type(Type type); /** - * object_delete: - * @obj: The object to free. - * - * Finalize an object and then free the memory associated with it. This should - * be paired with object_new() to free the resources associated with an object. - */ -void object_delete(Object *obj); - -/** * object_initialize_with_type: * @obj: A pointer to the memory to be used for the object. * @type: The type of the object to instantiate. @@ -573,8 +566,10 @@ void object_ref(Object *obj); * qdef_unref: * @obj: the object * - * Decrease the reference count of a object. A object cannot be freed as long + * Decrease the reference count of a object. A object is not freed as long * as its reference count is greater than zero. + * Once an object's reference count gets to zero (0), + * the object is finalized and the memory associated with it is freed. */ void object_unref(Object *obj); diff --git a/qom/object.c b/qom/object.c index 0cbd9bb..2de6eaf 100644 --- a/qom/object.c +++ b/qom/object.c @@ -328,7 +328,7 @@ static void object_deinit(Object *obj, TypeImpl *type) while (obj->interfaces) { Interface *iface_obj = obj->interfaces->data; obj->interfaces = g_slist_delete_link(obj->interfaces, obj->interfaces); - object_delete(OBJECT(iface_obj)); + object_unref(OBJECT(iface_obj)); }
Replace object_delete() with object_unref(). In the existing implementation, object_delete() calls object_unref(), then frees the object's storage. Running object_delete() on an object with reference count different from one (1) causes program failure. In the existing implementation, object_unref() finalizes the object when its reference count becomes zero (0). In the new implementation, object_unref() finalizes and frees the object's storage when the reference count becomes zero (0). One usage of object_delete() replaced by object_unref(). Signed-off-by: Alexander Barabash <alexander_barabash@mentor.com> if (type_has_parent(type)) { @@ -369,13 +369,6 @@ Object *object_new(const char *typename) return object_new_with_type(ti); } -void object_delete(Object *obj) -{ - object_unref(obj); - g_assert(obj->ref == 0); - g_free(obj); -} - static bool type_is_ancestor(TypeImpl *type, TypeImpl *target_type) { assert(target_type); @@ -583,6 +576,7 @@ void object_unref(Object *obj) /* parent always holds a reference to its children */ if (obj->ref == 0) { object_finalize(obj); + g_free(obj); } }