| Message ID | 20180912125531.32131-2-marcandre.lureau@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | hostmem-ram: use whole path for region name with >= 3.1 | expand |
On Wed, 12 Sep 2018 16:55:23 +0400 Marc-André Lureau <marcandre.lureau@redhat.com> wrote: > Improve a bit code readability. > > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> > --- > include/qom/object_interfaces.h | 4 ++++ > qom/object.c | 4 ++-- > qom/object_interfaces.c | 9 +++------ > 3 files changed, 9 insertions(+), 8 deletions(-) > > diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h > index 4d513fb329..46b0861457 100644 > --- a/include/qom/object_interfaces.h > +++ b/include/qom/object_interfaces.h > @@ -9,9 +9,13 @@ > #define USER_CREATABLE_CLASS(klass) \ > OBJECT_CLASS_CHECK(UserCreatableClass, (klass), \ > TYPE_USER_CREATABLE) > +#define IS_USER_CREATABLE_CLASS(klass) \ > + object_class_dynamic_cast(OBJECT_CLASS(oc), TYPE_USER_CREATABLE) > #define USER_CREATABLE_GET_CLASS(obj) \ > OBJECT_GET_CLASS(UserCreatableClass, (obj), \ > TYPE_USER_CREATABLE) > +#define IS_USER_CREATABLE(obj) \ > + object_dynamic_cast(OBJECT(obj), TYPE_USER_CREATABLE) > #define USER_CREATABLE(obj) \ > INTERFACE_CHECK(UserCreatable, (obj), \ > TYPE_USER_CREATABLE) > diff --git a/qom/object.c b/qom/object.c > index 75d1d48944..0703e8e4ff 100644 > --- a/qom/object.c > +++ b/qom/object.c > @@ -424,7 +424,7 @@ void object_initialize_childv(Object *parentobj, const char *propname, > goto out; > } > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > + if (IS_USER_CREATABLE(obj)) { > user_creatable_complete(obj, &local_err); > if (local_err) { > object_unparent(obj); > @@ -605,7 +605,7 @@ Object *object_new_with_propv(const char *typename, > goto error; > } > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > + if (IS_USER_CREATABLE(obj)) { > user_creatable_complete(obj, &local_err); > if (local_err) { > object_unparent(obj); > diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c > index 72b97a8bed..e3084bc04a 100644 > --- a/qom/object_interfaces.c > +++ b/qom/object_interfaces.c > @@ -10,18 +10,15 @@ > > void user_creatable_complete(Object *obj, Error **errp) > { > - > UserCreatableClass *ucc; > - UserCreatable *uc = > - (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE); > > - if (!uc) { > + if (!IS_USER_CREATABLE(obj)) { > return; > } > > - ucc = USER_CREATABLE_GET_CLASS(uc); > + ucc = USER_CREATABLE_GET_CLASS(obj); > if (ucc->complete) { > - ucc->complete(uc, errp); > + ucc->complete(USER_CREATABLE(obj), errp); ^^^ even though function becomes more concise, this will call expensive dynamic cast 2nd time (IS_USER_CREATABLE was the 1st and discarded) so I'm not sure is a good idea to regress startup time for readability. > } > } >
On Mon, Oct 22, 2018 at 03:33:30PM +0100, Igor Mammedov wrote: > On Wed, 12 Sep 2018 16:55:23 +0400 > Marc-André Lureau <marcandre.lureau@redhat.com> wrote: > > > Improve a bit code readability. > > > > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> > > --- > > include/qom/object_interfaces.h | 4 ++++ > > qom/object.c | 4 ++-- > > qom/object_interfaces.c | 9 +++------ > > 3 files changed, 9 insertions(+), 8 deletions(-) > > > > diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h > > index 4d513fb329..46b0861457 100644 > > --- a/include/qom/object_interfaces.h > > +++ b/include/qom/object_interfaces.h > > @@ -9,9 +9,13 @@ > > #define USER_CREATABLE_CLASS(klass) \ > > OBJECT_CLASS_CHECK(UserCreatableClass, (klass), \ > > TYPE_USER_CREATABLE) > > +#define IS_USER_CREATABLE_CLASS(klass) \ > > + object_class_dynamic_cast(OBJECT_CLASS(oc), TYPE_USER_CREATABLE) > > #define USER_CREATABLE_GET_CLASS(obj) \ > > OBJECT_GET_CLASS(UserCreatableClass, (obj), \ > > TYPE_USER_CREATABLE) > > +#define IS_USER_CREATABLE(obj) \ > > + object_dynamic_cast(OBJECT(obj), TYPE_USER_CREATABLE) > > #define USER_CREATABLE(obj) \ > > INTERFACE_CHECK(UserCreatable, (obj), \ > > TYPE_USER_CREATABLE) > > diff --git a/qom/object.c b/qom/object.c > > index 75d1d48944..0703e8e4ff 100644 > > --- a/qom/object.c > > +++ b/qom/object.c > > @@ -424,7 +424,7 @@ void object_initialize_childv(Object *parentobj, const char *propname, > > goto out; > > } > > > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > > + if (IS_USER_CREATABLE(obj)) { > > user_creatable_complete(obj, &local_err); > > if (local_err) { > > object_unparent(obj); > > @@ -605,7 +605,7 @@ Object *object_new_with_propv(const char *typename, > > goto error; > > } > > > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > > + if (IS_USER_CREATABLE(obj)) { > > user_creatable_complete(obj, &local_err); > > if (local_err) { > > object_unparent(obj); > > diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c > > index 72b97a8bed..e3084bc04a 100644 > > --- a/qom/object_interfaces.c > > +++ b/qom/object_interfaces.c > > @@ -10,18 +10,15 @@ > > > > void user_creatable_complete(Object *obj, Error **errp) > > { > > - > > UserCreatableClass *ucc; > > - UserCreatable *uc = > > - (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE); > > > > - if (!uc) { > > + if (!IS_USER_CREATABLE(obj)) { > > return; > > } > > > > - ucc = USER_CREATABLE_GET_CLASS(uc); > > + ucc = USER_CREATABLE_GET_CLASS(obj); > > if (ucc->complete) { > > - ucc->complete(uc, errp); > > + ucc->complete(USER_CREATABLE(obj), errp); > ^^^ > even though function becomes more concise, > this will call expensive dynamic cast 2nd time (IS_USER_CREATABLE was the 1st and discarded) > so I'm not sure is a good idea to regress startup time for readability. (INTERFACE_CHECK is a nop if CONFIG_QOM_CAST_DEBUG is not enabled, so I don't understand how it would regress startup time.
On Fri, 26 Oct 2018 12:13:21 -0300 Eduardo Habkost <ehabkost@redhat.com> wrote: > On Mon, Oct 22, 2018 at 03:33:30PM +0100, Igor Mammedov wrote: > > On Wed, 12 Sep 2018 16:55:23 +0400 > > Marc-André Lureau <marcandre.lureau@redhat.com> wrote: > > > > > Improve a bit code readability. > > > > > > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> > > > --- > > > include/qom/object_interfaces.h | 4 ++++ > > > qom/object.c | 4 ++-- > > > qom/object_interfaces.c | 9 +++------ > > > 3 files changed, 9 insertions(+), 8 deletions(-) > > > > > > diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h > > > index 4d513fb329..46b0861457 100644 > > > --- a/include/qom/object_interfaces.h > > > +++ b/include/qom/object_interfaces.h > > > @@ -9,9 +9,13 @@ > > > #define USER_CREATABLE_CLASS(klass) \ > > > OBJECT_CLASS_CHECK(UserCreatableClass, (klass), \ > > > TYPE_USER_CREATABLE) > > > +#define IS_USER_CREATABLE_CLASS(klass) \ > > > + object_class_dynamic_cast(OBJECT_CLASS(oc), TYPE_USER_CREATABLE) > > > #define USER_CREATABLE_GET_CLASS(obj) \ > > > OBJECT_GET_CLASS(UserCreatableClass, (obj), \ > > > TYPE_USER_CREATABLE) > > > +#define IS_USER_CREATABLE(obj) \ > > > + object_dynamic_cast(OBJECT(obj), TYPE_USER_CREATABLE) > > > #define USER_CREATABLE(obj) \ > > > INTERFACE_CHECK(UserCreatable, (obj), \ > > > TYPE_USER_CREATABLE) > > > diff --git a/qom/object.c b/qom/object.c > > > index 75d1d48944..0703e8e4ff 100644 > > > --- a/qom/object.c > > > +++ b/qom/object.c > > > @@ -424,7 +424,7 @@ void object_initialize_childv(Object *parentobj, const char *propname, > > > goto out; > > > } > > > > > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > > > + if (IS_USER_CREATABLE(obj)) { > > > user_creatable_complete(obj, &local_err); > > > if (local_err) { > > > object_unparent(obj); > > > @@ -605,7 +605,7 @@ Object *object_new_with_propv(const char *typename, > > > goto error; > > > } > > > > > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > > > + if (IS_USER_CREATABLE(obj)) { > > > user_creatable_complete(obj, &local_err); > > > if (local_err) { > > > object_unparent(obj); > > > diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c > > > index 72b97a8bed..e3084bc04a 100644 > > > --- a/qom/object_interfaces.c > > > +++ b/qom/object_interfaces.c > > > @@ -10,18 +10,15 @@ > > > > > > void user_creatable_complete(Object *obj, Error **errp) > > > { > > > - > > > UserCreatableClass *ucc; > > > - UserCreatable *uc = > > > - (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE); > > > > > > - if (!uc) { > > > + if (!IS_USER_CREATABLE(obj)) { > > > return; > > > } > > > > > > - ucc = USER_CREATABLE_GET_CLASS(uc); > > > + ucc = USER_CREATABLE_GET_CLASS(obj); > > > if (ucc->complete) { > > > - ucc->complete(uc, errp); > > > + ucc->complete(USER_CREATABLE(obj), errp); > > ^^^ > > even though function becomes more concise, > > this will call expensive dynamic cast 2nd time (IS_USER_CREATABLE was the 1st and discarded) > > so I'm not sure is a good idea to regress startup time for readability. > > (INTERFACE_CHECK is a nop if CONFIG_QOM_CAST_DEBUG is not > enabled, so I don't understand how it would regress startup time. Isn't it enabled by default though? Maybe we should flip default to disabled then cast should be ok and enable it when generic '--debug' is enabled.
On Mon, Oct 29, 2018 at 10:56:57AM +0100, Igor Mammedov wrote: > On Fri, 26 Oct 2018 12:13:21 -0300 > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > On Mon, Oct 22, 2018 at 03:33:30PM +0100, Igor Mammedov wrote: > > > On Wed, 12 Sep 2018 16:55:23 +0400 > > > Marc-André Lureau <marcandre.lureau@redhat.com> wrote: > > > > > > > Improve a bit code readability. > > > > > > > > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> > > > > --- > > > > include/qom/object_interfaces.h | 4 ++++ > > > > qom/object.c | 4 ++-- > > > > qom/object_interfaces.c | 9 +++------ > > > > 3 files changed, 9 insertions(+), 8 deletions(-) > > > > > > > > diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h > > > > index 4d513fb329..46b0861457 100644 > > > > --- a/include/qom/object_interfaces.h > > > > +++ b/include/qom/object_interfaces.h > > > > @@ -9,9 +9,13 @@ > > > > #define USER_CREATABLE_CLASS(klass) \ > > > > OBJECT_CLASS_CHECK(UserCreatableClass, (klass), \ > > > > TYPE_USER_CREATABLE) > > > > +#define IS_USER_CREATABLE_CLASS(klass) \ > > > > + object_class_dynamic_cast(OBJECT_CLASS(oc), TYPE_USER_CREATABLE) > > > > #define USER_CREATABLE_GET_CLASS(obj) \ > > > > OBJECT_GET_CLASS(UserCreatableClass, (obj), \ > > > > TYPE_USER_CREATABLE) > > > > +#define IS_USER_CREATABLE(obj) \ > > > > + object_dynamic_cast(OBJECT(obj), TYPE_USER_CREATABLE) > > > > #define USER_CREATABLE(obj) \ > > > > INTERFACE_CHECK(UserCreatable, (obj), \ > > > > TYPE_USER_CREATABLE) > > > > diff --git a/qom/object.c b/qom/object.c > > > > index 75d1d48944..0703e8e4ff 100644 > > > > --- a/qom/object.c > > > > +++ b/qom/object.c > > > > @@ -424,7 +424,7 @@ void object_initialize_childv(Object *parentobj, const char *propname, > > > > goto out; > > > > } > > > > > > > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > > > > + if (IS_USER_CREATABLE(obj)) { > > > > user_creatable_complete(obj, &local_err); > > > > if (local_err) { > > > > object_unparent(obj); > > > > @@ -605,7 +605,7 @@ Object *object_new_with_propv(const char *typename, > > > > goto error; > > > > } > > > > > > > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > > > > + if (IS_USER_CREATABLE(obj)) { > > > > user_creatable_complete(obj, &local_err); > > > > if (local_err) { > > > > object_unparent(obj); > > > > diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c > > > > index 72b97a8bed..e3084bc04a 100644 > > > > --- a/qom/object_interfaces.c > > > > +++ b/qom/object_interfaces.c > > > > @@ -10,18 +10,15 @@ > > > > > > > > void user_creatable_complete(Object *obj, Error **errp) > > > > { > > > > - > > > > UserCreatableClass *ucc; > > > > - UserCreatable *uc = > > > > - (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE); > > > > > > > > - if (!uc) { > > > > + if (!IS_USER_CREATABLE(obj)) { > > > > return; > > > > } > > > > > > > > - ucc = USER_CREATABLE_GET_CLASS(uc); > > > > + ucc = USER_CREATABLE_GET_CLASS(obj); > > > > if (ucc->complete) { > > > > - ucc->complete(uc, errp); > > > > + ucc->complete(USER_CREATABLE(obj), errp); > > > ^^^ > > > even though function becomes more concise, > > > this will call expensive dynamic cast 2nd time (IS_USER_CREATABLE was the 1st and discarded) > > > so I'm not sure is a good idea to regress startup time for readability. > > > > (INTERFACE_CHECK is a nop if CONFIG_QOM_CAST_DEBUG is not > > enabled, so I don't understand how it would regress startup time. > Isn't it enabled by default though? > Maybe we should flip default to disabled then cast should be ok and enable it > when generic '--debug' is enabled. This is called only once for each -object option. Even if QOM debugging is enabled by default I don't see why it wouldn't be OK to call object_dynamic_cast_assert() here.
Hi On Tue, Oct 30, 2018 at 5:37 AM Eduardo Habkost <ehabkost@redhat.com> wrote: > > On Mon, Oct 29, 2018 at 10:56:57AM +0100, Igor Mammedov wrote: > > On Fri, 26 Oct 2018 12:13:21 -0300 > > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > On Mon, Oct 22, 2018 at 03:33:30PM +0100, Igor Mammedov wrote: > > > > On Wed, 12 Sep 2018 16:55:23 +0400 > > > > Marc-André Lureau <marcandre.lureau@redhat.com> wrote: > > > > > > > > > Improve a bit code readability. > > > > > > > > > > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> > > > > > --- > > > > > include/qom/object_interfaces.h | 4 ++++ > > > > > qom/object.c | 4 ++-- > > > > > qom/object_interfaces.c | 9 +++------ > > > > > 3 files changed, 9 insertions(+), 8 deletions(-) > > > > > > > > > > diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h > > > > > index 4d513fb329..46b0861457 100644 > > > > > --- a/include/qom/object_interfaces.h > > > > > +++ b/include/qom/object_interfaces.h > > > > > @@ -9,9 +9,13 @@ > > > > > #define USER_CREATABLE_CLASS(klass) \ > > > > > OBJECT_CLASS_CHECK(UserCreatableClass, (klass), \ > > > > > TYPE_USER_CREATABLE) > > > > > +#define IS_USER_CREATABLE_CLASS(klass) \ > > > > > + object_class_dynamic_cast(OBJECT_CLASS(oc), TYPE_USER_CREATABLE) > > > > > #define USER_CREATABLE_GET_CLASS(obj) \ > > > > > OBJECT_GET_CLASS(UserCreatableClass, (obj), \ > > > > > TYPE_USER_CREATABLE) > > > > > +#define IS_USER_CREATABLE(obj) \ > > > > > + object_dynamic_cast(OBJECT(obj), TYPE_USER_CREATABLE) > > > > > #define USER_CREATABLE(obj) \ > > > > > INTERFACE_CHECK(UserCreatable, (obj), \ > > > > > TYPE_USER_CREATABLE) > > > > > diff --git a/qom/object.c b/qom/object.c > > > > > index 75d1d48944..0703e8e4ff 100644 > > > > > --- a/qom/object.c > > > > > +++ b/qom/object.c > > > > > @@ -424,7 +424,7 @@ void object_initialize_childv(Object *parentobj, const char *propname, > > > > > goto out; > > > > > } > > > > > > > > > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > > > > > + if (IS_USER_CREATABLE(obj)) { > > > > > user_creatable_complete(obj, &local_err); > > > > > if (local_err) { > > > > > object_unparent(obj); > > > > > @@ -605,7 +605,7 @@ Object *object_new_with_propv(const char *typename, > > > > > goto error; > > > > > } > > > > > > > > > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > > > > > + if (IS_USER_CREATABLE(obj)) { > > > > > user_creatable_complete(obj, &local_err); > > > > > if (local_err) { > > > > > object_unparent(obj); > > > > > diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c > > > > > index 72b97a8bed..e3084bc04a 100644 > > > > > --- a/qom/object_interfaces.c > > > > > +++ b/qom/object_interfaces.c > > > > > @@ -10,18 +10,15 @@ > > > > > > > > > > void user_creatable_complete(Object *obj, Error **errp) > > > > > { > > > > > - > > > > > UserCreatableClass *ucc; > > > > > - UserCreatable *uc = > > > > > - (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE); > > > > > > > > > > - if (!uc) { > > > > > + if (!IS_USER_CREATABLE(obj)) { > > > > > return; > > > > > } > > > > > > > > > > - ucc = USER_CREATABLE_GET_CLASS(uc); > > > > > + ucc = USER_CREATABLE_GET_CLASS(obj); > > > > > if (ucc->complete) { > > > > > - ucc->complete(uc, errp); > > > > > + ucc->complete(USER_CREATABLE(obj), errp); > > > > ^^^ > > > > even though function becomes more concise, > > > > this will call expensive dynamic cast 2nd time (IS_USER_CREATABLE was the 1st and discarded) > > > > so I'm not sure is a good idea to regress startup time for readability. I hope it's not measurable, unless we create billions of objects. Do you want some figures? > > > > > > (INTERFACE_CHECK is a nop if CONFIG_QOM_CAST_DEBUG is not > > > enabled, so I don't understand how it would regress startup time. > > Isn't it enabled by default though? > > Maybe we should flip default to disabled then cast should be ok and enable it > > when generic '--debug' is enabled. > > This is called only once for each -object option. Even if QOM > debugging is enabled by default I don't see why it wouldn't be OK > to call object_dynamic_cast_assert() here. Yes, imho it's very marginal. Thus I would value more readability. Alternatively, we can consider replacing ucc->complete(USER_CREATABLE(obj), errp); by ucc->complete((UserCreatable*)obj, errp); to get back to the same number of dynamic_cast calls.
On Tue, 30 Oct 2018 13:26:40 +0400 Marc-André Lureau <marcandre.lureau@redhat.com> wrote: > Hi > > On Tue, Oct 30, 2018 at 5:37 AM Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > On Mon, Oct 29, 2018 at 10:56:57AM +0100, Igor Mammedov wrote: > > > On Fri, 26 Oct 2018 12:13:21 -0300 > > > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > > > On Mon, Oct 22, 2018 at 03:33:30PM +0100, Igor Mammedov wrote: > > > > > On Wed, 12 Sep 2018 16:55:23 +0400 > > > > > Marc-André Lureau <marcandre.lureau@redhat.com> wrote: > > > > > > > > > > > Improve a bit code readability. > > > > > > > > > > > > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> > > > > > > --- > > > > > > include/qom/object_interfaces.h | 4 ++++ > > > > > > qom/object.c | 4 ++-- > > > > > > qom/object_interfaces.c | 9 +++------ > > > > > > 3 files changed, 9 insertions(+), 8 deletions(-) > > > > > > > > > > > > diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h > > > > > > index 4d513fb329..46b0861457 100644 > > > > > > --- a/include/qom/object_interfaces.h > > > > > > +++ b/include/qom/object_interfaces.h > > > > > > @@ -9,9 +9,13 @@ > > > > > > #define USER_CREATABLE_CLASS(klass) \ > > > > > > OBJECT_CLASS_CHECK(UserCreatableClass, (klass), \ > > > > > > TYPE_USER_CREATABLE) > > > > > > +#define IS_USER_CREATABLE_CLASS(klass) \ > > > > > > + object_class_dynamic_cast(OBJECT_CLASS(oc), TYPE_USER_CREATABLE) > > > > > > #define USER_CREATABLE_GET_CLASS(obj) \ > > > > > > OBJECT_GET_CLASS(UserCreatableClass, (obj), \ > > > > > > TYPE_USER_CREATABLE) > > > > > > +#define IS_USER_CREATABLE(obj) \ > > > > > > + object_dynamic_cast(OBJECT(obj), TYPE_USER_CREATABLE) > > > > > > #define USER_CREATABLE(obj) \ > > > > > > INTERFACE_CHECK(UserCreatable, (obj), \ > > > > > > TYPE_USER_CREATABLE) > > > > > > diff --git a/qom/object.c b/qom/object.c > > > > > > index 75d1d48944..0703e8e4ff 100644 > > > > > > --- a/qom/object.c > > > > > > +++ b/qom/object.c > > > > > > @@ -424,7 +424,7 @@ void object_initialize_childv(Object *parentobj, const char *propname, > > > > > > goto out; > > > > > > } > > > > > > > > > > > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > > > > > > + if (IS_USER_CREATABLE(obj)) { > > > > > > user_creatable_complete(obj, &local_err); > > > > > > if (local_err) { > > > > > > object_unparent(obj); > > > > > > @@ -605,7 +605,7 @@ Object *object_new_with_propv(const char *typename, > > > > > > goto error; > > > > > > } > > > > > > > > > > > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > > > > > > + if (IS_USER_CREATABLE(obj)) { > > > > > > user_creatable_complete(obj, &local_err); > > > > > > if (local_err) { > > > > > > object_unparent(obj); > > > > > > diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c > > > > > > index 72b97a8bed..e3084bc04a 100644 > > > > > > --- a/qom/object_interfaces.c > > > > > > +++ b/qom/object_interfaces.c > > > > > > @@ -10,18 +10,15 @@ > > > > > > > > > > > > void user_creatable_complete(Object *obj, Error **errp) > > > > > > { > > > > > > - > > > > > > UserCreatableClass *ucc; > > > > > > - UserCreatable *uc = > > > > > > - (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE); > > > > > > > > > > > > - if (!uc) { > > > > > > + if (!IS_USER_CREATABLE(obj)) { > > > > > > return; > > > > > > } > > > > > > > > > > > > - ucc = USER_CREATABLE_GET_CLASS(uc); > > > > > > + ucc = USER_CREATABLE_GET_CLASS(obj); > > > > > > if (ucc->complete) { > > > > > > - ucc->complete(uc, errp); > > > > > > + ucc->complete(USER_CREATABLE(obj), errp); > > > > > ^^^ > > > > > even though function becomes more concise, > > > > > this will call expensive dynamic cast 2nd time (IS_USER_CREATABLE was the 1st and discarded) > > > > > so I'm not sure is a good idea to regress startup time for readability. > > I hope it's not measurable, unless we create billions of objects. Do > you want some figures? I recall penalty was big enough for QEMU, that we added qom debug option, in case of -object, the cost could be multiplied by hundreds > > > > (INTERFACE_CHECK is a nop if CONFIG_QOM_CAST_DEBUG is not > > > > enabled, so I don't understand how it would regress startup time. > > > Isn't it enabled by default though? > > > Maybe we should flip default to disabled then cast should be ok and enable it > > > when generic '--debug' is enabled. > > > > This is called only once for each -object option. Even if QOM > > debugging is enabled by default I don't see why it wouldn't be OK > > to call object_dynamic_cast_assert() here. > > Yes, imho it's very marginal. Thus I would value more readability. Probably not marginal for folks who are trying to reduce every tiny bit of start up time. Considering readablity change here doesn't really make a difference, I'd pick performance. i.e. do cast and then reuse result later. > Alternatively, we can consider replacing > ucc->complete(USER_CREATABLE(obj), errp); by > ucc->complete((UserCreatable*)obj, errp); to get back to the same > number of dynamic_cast calls. Unsafe casts (foo*) typically frowned upon but it should be safe since one gets here after IS_USER_CREATABLE check, so I don't really care in this case. But I'd drop user_creatable_complete() hunk, so that original cast result is being reused.
On Tue, Oct 30, 2018 at 03:22:43PM +0100, Igor Mammedov wrote: > On Tue, 30 Oct 2018 13:26:40 +0400 > Marc-André Lureau <marcandre.lureau@redhat.com> wrote: > > > Hi > > > > On Tue, Oct 30, 2018 at 5:37 AM Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > > On Mon, Oct 29, 2018 at 10:56:57AM +0100, Igor Mammedov wrote: > > > > On Fri, 26 Oct 2018 12:13:21 -0300 > > > > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > > > > > On Mon, Oct 22, 2018 at 03:33:30PM +0100, Igor Mammedov wrote: > > > > > > On Wed, 12 Sep 2018 16:55:23 +0400 > > > > > > Marc-André Lureau <marcandre.lureau@redhat.com> wrote: > > > > > > > > > > > > > Improve a bit code readability. > > > > > > > > > > > > > > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> > > > > > > > --- > > > > > > > include/qom/object_interfaces.h | 4 ++++ > > > > > > > qom/object.c | 4 ++-- > > > > > > > qom/object_interfaces.c | 9 +++------ > > > > > > > 3 files changed, 9 insertions(+), 8 deletions(-) > > > > > > > > > > > > > > diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h > > > > > > > index 4d513fb329..46b0861457 100644 > > > > > > > --- a/include/qom/object_interfaces.h > > > > > > > +++ b/include/qom/object_interfaces.h > > > > > > > @@ -9,9 +9,13 @@ > > > > > > > #define USER_CREATABLE_CLASS(klass) \ > > > > > > > OBJECT_CLASS_CHECK(UserCreatableClass, (klass), \ > > > > > > > TYPE_USER_CREATABLE) > > > > > > > +#define IS_USER_CREATABLE_CLASS(klass) \ > > > > > > > + object_class_dynamic_cast(OBJECT_CLASS(oc), TYPE_USER_CREATABLE) > > > > > > > #define USER_CREATABLE_GET_CLASS(obj) \ > > > > > > > OBJECT_GET_CLASS(UserCreatableClass, (obj), \ > > > > > > > TYPE_USER_CREATABLE) > > > > > > > +#define IS_USER_CREATABLE(obj) \ > > > > > > > + object_dynamic_cast(OBJECT(obj), TYPE_USER_CREATABLE) > > > > > > > #define USER_CREATABLE(obj) \ > > > > > > > INTERFACE_CHECK(UserCreatable, (obj), \ > > > > > > > TYPE_USER_CREATABLE) > > > > > > > diff --git a/qom/object.c b/qom/object.c > > > > > > > index 75d1d48944..0703e8e4ff 100644 > > > > > > > --- a/qom/object.c > > > > > > > +++ b/qom/object.c > > > > > > > @@ -424,7 +424,7 @@ void object_initialize_childv(Object *parentobj, const char *propname, > > > > > > > goto out; > > > > > > > } > > > > > > > > > > > > > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > > > > > > > + if (IS_USER_CREATABLE(obj)) { > > > > > > > user_creatable_complete(obj, &local_err); > > > > > > > if (local_err) { > > > > > > > object_unparent(obj); > > > > > > > @@ -605,7 +605,7 @@ Object *object_new_with_propv(const char *typename, > > > > > > > goto error; > > > > > > > } > > > > > > > > > > > > > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > > > > > > > + if (IS_USER_CREATABLE(obj)) { > > > > > > > user_creatable_complete(obj, &local_err); > > > > > > > if (local_err) { > > > > > > > object_unparent(obj); > > > > > > > diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c > > > > > > > index 72b97a8bed..e3084bc04a 100644 > > > > > > > --- a/qom/object_interfaces.c > > > > > > > +++ b/qom/object_interfaces.c > > > > > > > @@ -10,18 +10,15 @@ > > > > > > > > > > > > > > void user_creatable_complete(Object *obj, Error **errp) > > > > > > > { > > > > > > > - > > > > > > > UserCreatableClass *ucc; > > > > > > > - UserCreatable *uc = > > > > > > > - (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE); > > > > > > > > > > > > > > - if (!uc) { > > > > > > > + if (!IS_USER_CREATABLE(obj)) { > > > > > > > return; > > > > > > > } > > > > > > > > > > > > > > - ucc = USER_CREATABLE_GET_CLASS(uc); > > > > > > > + ucc = USER_CREATABLE_GET_CLASS(obj); > > > > > > > if (ucc->complete) { > > > > > > > - ucc->complete(uc, errp); > > > > > > > + ucc->complete(USER_CREATABLE(obj), errp); > > > > > > ^^^ > > > > > > even though function becomes more concise, > > > > > > this will call expensive dynamic cast 2nd time (IS_USER_CREATABLE was the 1st and discarded) > > > > > > so I'm not sure is a good idea to regress startup time for readability. > > > > I hope it's not measurable, unless we create billions of objects. Do > > you want some figures? > I recall penalty was big enough for QEMU, that we added qom debug option, > in case of -object, the cost could be multiplied by hundreds This sounds like premature optimization. Did you measure how many nanoseconds we're saving per -object option? > > > > > (INTERFACE_CHECK is a nop if CONFIG_QOM_CAST_DEBUG is not > > > > > enabled, so I don't understand how it would regress startup time. > > > > Isn't it enabled by default though? > > > > Maybe we should flip default to disabled then cast should be ok and enable it > > > > when generic '--debug' is enabled. > > > > > > This is called only once for each -object option. Even if QOM > > > debugging is enabled by default I don't see why it wouldn't be OK > > > to call object_dynamic_cast_assert() here. > > > > Yes, imho it's very marginal. Thus I would value more readability. > Probably not marginal for folks who are trying to reduce every > tiny bit of start up time. These people should be disabling QOM debugging, then. > > Considering readablity change here doesn't really make a difference, > I'd pick performance. i.e. do cast and then reuse result later. > > > Alternatively, we can consider replacing > > ucc->complete(USER_CREATABLE(obj), errp); by > > ucc->complete((UserCreatable*)obj, errp); to get back to the same > > number of dynamic_cast calls. > Unsafe casts (foo*) typically frowned upon but it should be safe > since one gets here after IS_USER_CREATABLE check, so I don't really > care in this case. But I'd drop user_creatable_complete() hunk, > so that original cast result is being reused. Please don't do that. Readability, safety, and consistency are more important. For the few users where QOM debugging has a measurable performance impact, we already have a mechanism to disable it.
On Tue, 30 Oct 2018 20:07:17 -0300 Eduardo Habkost <ehabkost@redhat.com> wrote: > On Tue, Oct 30, 2018 at 03:22:43PM +0100, Igor Mammedov wrote: > > On Tue, 30 Oct 2018 13:26:40 +0400 > > Marc-André Lureau <marcandre.lureau@redhat.com> wrote: > > > > > Hi > > > > > > On Tue, Oct 30, 2018 at 5:37 AM Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > > > > On Mon, Oct 29, 2018 at 10:56:57AM +0100, Igor Mammedov wrote: > > > > > On Fri, 26 Oct 2018 12:13:21 -0300 > > > > > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > > > > > > > On Mon, Oct 22, 2018 at 03:33:30PM +0100, Igor Mammedov wrote: > > > > > > > On Wed, 12 Sep 2018 16:55:23 +0400 > > > > > > > Marc-André Lureau <marcandre.lureau@redhat.com> wrote: > > > > > > > > > > > > > > > Improve a bit code readability. > > > > > > > > > > > > > > > > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> > > > > > > > > --- > > > > > > > > include/qom/object_interfaces.h | 4 ++++ > > > > > > > > qom/object.c | 4 ++-- > > > > > > > > qom/object_interfaces.c | 9 +++------ > > > > > > > > 3 files changed, 9 insertions(+), 8 deletions(-) > > > > > > > > > > > > > > > > diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h > > > > > > > > index 4d513fb329..46b0861457 100644 > > > > > > > > --- a/include/qom/object_interfaces.h > > > > > > > > +++ b/include/qom/object_interfaces.h > > > > > > > > @@ -9,9 +9,13 @@ > > > > > > > > #define USER_CREATABLE_CLASS(klass) \ > > > > > > > > OBJECT_CLASS_CHECK(UserCreatableClass, (klass), \ > > > > > > > > TYPE_USER_CREATABLE) > > > > > > > > +#define IS_USER_CREATABLE_CLASS(klass) \ > > > > > > > > + object_class_dynamic_cast(OBJECT_CLASS(oc), TYPE_USER_CREATABLE) > > > > > > > > #define USER_CREATABLE_GET_CLASS(obj) \ > > > > > > > > OBJECT_GET_CLASS(UserCreatableClass, (obj), \ > > > > > > > > TYPE_USER_CREATABLE) > > > > > > > > +#define IS_USER_CREATABLE(obj) \ > > > > > > > > + object_dynamic_cast(OBJECT(obj), TYPE_USER_CREATABLE) > > > > > > > > #define USER_CREATABLE(obj) \ > > > > > > > > INTERFACE_CHECK(UserCreatable, (obj), \ > > > > > > > > TYPE_USER_CREATABLE) > > > > > > > > diff --git a/qom/object.c b/qom/object.c > > > > > > > > index 75d1d48944..0703e8e4ff 100644 > > > > > > > > --- a/qom/object.c > > > > > > > > +++ b/qom/object.c > > > > > > > > @@ -424,7 +424,7 @@ void object_initialize_childv(Object *parentobj, const char *propname, > > > > > > > > goto out; > > > > > > > > } > > > > > > > > > > > > > > > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > > > > > > > > + if (IS_USER_CREATABLE(obj)) { > > > > > > > > user_creatable_complete(obj, &local_err); > > > > > > > > if (local_err) { > > > > > > > > object_unparent(obj); > > > > > > > > @@ -605,7 +605,7 @@ Object *object_new_with_propv(const char *typename, > > > > > > > > goto error; > > > > > > > > } > > > > > > > > > > > > > > > > - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { > > > > > > > > + if (IS_USER_CREATABLE(obj)) { > > > > > > > > user_creatable_complete(obj, &local_err); > > > > > > > > if (local_err) { > > > > > > > > object_unparent(obj); > > > > > > > > diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c > > > > > > > > index 72b97a8bed..e3084bc04a 100644 > > > > > > > > --- a/qom/object_interfaces.c > > > > > > > > +++ b/qom/object_interfaces.c > > > > > > > > @@ -10,18 +10,15 @@ > > > > > > > > > > > > > > > > void user_creatable_complete(Object *obj, Error **errp) > > > > > > > > { > > > > > > > > - > > > > > > > > UserCreatableClass *ucc; > > > > > > > > - UserCreatable *uc = > > > > > > > > - (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE); > > > > > > > > > > > > > > > > - if (!uc) { > > > > > > > > + if (!IS_USER_CREATABLE(obj)) { > > > > > > > > return; > > > > > > > > } > > > > > > > > > > > > > > > > - ucc = USER_CREATABLE_GET_CLASS(uc); > > > > > > > > + ucc = USER_CREATABLE_GET_CLASS(obj); > > > > > > > > if (ucc->complete) { > > > > > > > > - ucc->complete(uc, errp); > > > > > > > > + ucc->complete(USER_CREATABLE(obj), errp); > > > > > > > ^^^ > > > > > > > even though function becomes more concise, > > > > > > > this will call expensive dynamic cast 2nd time (IS_USER_CREATABLE was the 1st and discarded) > > > > > > > so I'm not sure is a good idea to regress startup time for readability. > > > > > > I hope it's not measurable, unless we create billions of objects. Do > > > you want some figures? > > I recall penalty was big enough for QEMU, that we added qom debug option, > > in case of -object, the cost could be multiplied by hundreds > > This sounds like premature optimization. Did you measure how > many nanoseconds we're saving per -object option? it's not optimization, it's about not making code worse and using resources reasonably object_dynamic_cast() with IS_USER_CREATABLE(). I'd replace object_dynamic_cast() with IS_FOO() in places where we just test but do not use the result for a better readability. But is we need the result later I'd keep object_dynamic_cast(), it's not much worse but allows us to reuse the result of cast. > > > > > > (INTERFACE_CHECK is a nop if CONFIG_QOM_CAST_DEBUG is not > > > > > > enabled, so I don't understand how it would regress startup time. > > > > > Isn't it enabled by default though? > > > > > Maybe we should flip default to disabled then cast should be ok and enable it > > > > > when generic '--debug' is enabled. > > > > > > > > This is called only once for each -object option. Even if QOM > > > > debugging is enabled by default I don't see why it wouldn't be OK > > > > to call object_dynamic_cast_assert() here. > > > > > > Yes, imho it's very marginal. Thus I would value more readability. > > Probably not marginal for folks who are trying to reduce every > > tiny bit of start up time. > > These people should be disabling QOM debugging, then. > > > > > Considering readablity change here doesn't really make a difference, > > I'd pick performance. i.e. do cast and then reuse result later. > > > > > Alternatively, we can consider replacing > > > ucc->complete(USER_CREATABLE(obj), errp); by > > > ucc->complete((UserCreatable*)obj, errp); to get back to the same > > > number of dynamic_cast calls. > > Unsafe casts (foo*) typically frowned upon but it should be safe > > since one gets here after IS_USER_CREATABLE check, so I don't really > > care in this case. But I'd drop user_creatable_complete() hunk, > > so that original cast result is being reused. > > Please don't do that. Readability, safety, and consistency are > more important. For the few users where QOM debugging has a > measurable performance impact, we already have a mechanism to > disable it.
On Thu, Nov 01, 2018 at 01:16:37PM +0100, Igor Mammedov wrote: > On Tue, 30 Oct 2018 20:07:17 -0300 > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > On Tue, Oct 30, 2018 at 03:22:43PM +0100, Igor Mammedov wrote: > > > On Tue, 30 Oct 2018 13:26:40 +0400 > > > Marc-André Lureau <marcandre.lureau@redhat.com> wrote: > > > > > > > Hi > > > > > > > > On Tue, Oct 30, 2018 at 5:37 AM Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > > > > > > On Mon, Oct 29, 2018 at 10:56:57AM +0100, Igor Mammedov wrote: > > > > > > On Fri, 26 Oct 2018 12:13:21 -0300 > > > > > > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > > > > > > > > > On Mon, Oct 22, 2018 at 03:33:30PM +0100, Igor Mammedov wrote: > > > > > > > > On Wed, 12 Sep 2018 16:55:23 +0400 > > > > > > > > Marc-André Lureau <marcandre.lureau@redhat.com> wrote: [...] > > > > > > > > > void user_creatable_complete(Object *obj, Error **errp) > > > > > > > > > { > > > > > > > > > - > > > > > > > > > UserCreatableClass *ucc; > > > > > > > > > - UserCreatable *uc = > > > > > > > > > - (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE); > > > > > > > > > > > > > > > > > > - if (!uc) { > > > > > > > > > + if (!IS_USER_CREATABLE(obj)) { > > > > > > > > > return; > > > > > > > > > } > > > > > > > > > > > > > > > > > > - ucc = USER_CREATABLE_GET_CLASS(uc); > > > > > > > > > + ucc = USER_CREATABLE_GET_CLASS(obj); > > > > > > > > > if (ucc->complete) { > > > > > > > > > - ucc->complete(uc, errp); > > > > > > > > > + ucc->complete(USER_CREATABLE(obj), errp); > > > > > > > > ^^^ > > > > > > > > even though function becomes more concise, > > > > > > > > this will call expensive dynamic cast 2nd time (IS_USER_CREATABLE was the 1st and discarded) > > > > > > > > so I'm not sure is a good idea to regress startup time for readability. > > > > > > > > I hope it's not measurable, unless we create billions of objects. Do > > > > you want some figures? > > > I recall penalty was big enough for QEMU, that we added qom debug option, > > > in case of -object, the cost could be multiplied by hundreds > > > > This sounds like premature optimization. Did you measure how > > many nanoseconds we're saving per -object option? > it's not optimization, it's about not making code worse and using > resources reasonably object_dynamic_cast() with IS_USER_CREATABLE(). How exactly is the code worse? > > I'd replace object_dynamic_cast() with IS_FOO() in places where > we just test but do not use the result for a better readability. > But is we need the result later I'd keep object_dynamic_cast(), > it's not much worse but allows us to reuse the result of cast. Readability is orders of magnitude more important to me. This is not readable: (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE) This is readable: USER_CREATABLE(obj) If the overhead of the extra object_dynamic_cast() call is too much, it's already possible to disable QOM cast debugging. > [...]
On Thu, 1 Nov 2018 12:02:03 -0300 Eduardo Habkost <ehabkost@redhat.com> wrote: > On Thu, Nov 01, 2018 at 01:16:37PM +0100, Igor Mammedov wrote: > > On Tue, 30 Oct 2018 20:07:17 -0300 > > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > On Tue, Oct 30, 2018 at 03:22:43PM +0100, Igor Mammedov wrote: > > > > On Tue, 30 Oct 2018 13:26:40 +0400 > > > > Marc-André Lureau <marcandre.lureau@redhat.com> wrote: > > > > > > > > > Hi > > > > > > > > > > On Tue, Oct 30, 2018 at 5:37 AM Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > > > > > > > > On Mon, Oct 29, 2018 at 10:56:57AM +0100, Igor Mammedov wrote: > > > > > > > On Fri, 26 Oct 2018 12:13:21 -0300 > > > > > > > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > > > > > > > > > > > On Mon, Oct 22, 2018 at 03:33:30PM +0100, Igor Mammedov wrote: > > > > > > > > > On Wed, 12 Sep 2018 16:55:23 +0400 > > > > > > > > > Marc-André Lureau <marcandre.lureau@redhat.com> wrote: > [...] > > > > > > > > > > void user_creatable_complete(Object *obj, Error **errp) > > > > > > > > > > { > > > > > > > > > > - > > > > > > > > > > UserCreatableClass *ucc; > > > > > > > > > > - UserCreatable *uc = > > > > > > > > > > - (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE); > > > > > > > > > > > > > > > > > > > > - if (!uc) { > > > > > > > > > > + if (!IS_USER_CREATABLE(obj)) { > > > > > > > > > > return; > > > > > > > > > > } > > > > > > > > > > > > > > > > > > > > - ucc = USER_CREATABLE_GET_CLASS(uc); > > > > > > > > > > + ucc = USER_CREATABLE_GET_CLASS(obj); > > > > > > > > > > if (ucc->complete) { > > > > > > > > > > - ucc->complete(uc, errp); > > > > > > > > > > + ucc->complete(USER_CREATABLE(obj), errp); > > > > > > > > > ^^^ > > > > > > > > > even though function becomes more concise, > > > > > > > > > this will call expensive dynamic cast 2nd time (IS_USER_CREATABLE was the 1st and discarded) > > > > > > > > > so I'm not sure is a good idea to regress startup time for readability. > > > > > > > > > > I hope it's not measurable, unless we create billions of objects. Do > > > > > you want some figures? > > > > I recall penalty was big enough for QEMU, that we added qom debug option, > > > > in case of -object, the cost could be multiplied by hundreds > > > > > > This sounds like premature optimization. Did you measure how > > > many nanoseconds we're saving per -object option? > > it's not optimization, it's about not making code worse and using > > resources reasonably object_dynamic_cast() with IS_USER_CREATABLE(). > > How exactly is the code worse? making it slower /doesn't matter how much/ when there is better way to do it. Anyways the point is moot as Mark rewrote it in another way (better) so this question won't arise. > > > > I'd replace object_dynamic_cast() with IS_FOO() in places where > > we just test but do not use the result for a better readability. > > But is we need the result later I'd keep object_dynamic_cast(), > > it's not much worse but allows us to reuse the result of cast. > > Readability is orders of magnitude more important to me. > > This is not readable: > (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE) > > This is readable: > USER_CREATABLE(obj) > > If the overhead of the extra object_dynamic_cast() call is too > much, it's already possible to disable QOM cast debugging. I'm typically on the side of simplifying code and readability but in this case I have to disagree, out of context ^^^ it might look fine but with full context uc = (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE) if(uc) call(uc) vs if(IS_USER_CREATABLE(obj)) // discard above hidden cast result and do it again call(USER_CREATABLE(obj)) the former is not horrible enough to warrant doing senseless discard. So lets agree to disagree :) > > > [...] >
diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h index 4d513fb329..46b0861457 100644 --- a/include/qom/object_interfaces.h +++ b/include/qom/object_interfaces.h @@ -9,9 +9,13 @@ #define USER_CREATABLE_CLASS(klass) \ OBJECT_CLASS_CHECK(UserCreatableClass, (klass), \ TYPE_USER_CREATABLE) +#define IS_USER_CREATABLE_CLASS(klass) \ + object_class_dynamic_cast(OBJECT_CLASS(oc), TYPE_USER_CREATABLE) #define USER_CREATABLE_GET_CLASS(obj) \ OBJECT_GET_CLASS(UserCreatableClass, (obj), \ TYPE_USER_CREATABLE) +#define IS_USER_CREATABLE(obj) \ + object_dynamic_cast(OBJECT(obj), TYPE_USER_CREATABLE) #define USER_CREATABLE(obj) \ INTERFACE_CHECK(UserCreatable, (obj), \ TYPE_USER_CREATABLE) diff --git a/qom/object.c b/qom/object.c index 75d1d48944..0703e8e4ff 100644 --- a/qom/object.c +++ b/qom/object.c @@ -424,7 +424,7 @@ void object_initialize_childv(Object *parentobj, const char *propname, goto out; } - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { + if (IS_USER_CREATABLE(obj)) { user_creatable_complete(obj, &local_err); if (local_err) { object_unparent(obj); @@ -605,7 +605,7 @@ Object *object_new_with_propv(const char *typename, goto error; } - if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) { + if (IS_USER_CREATABLE(obj)) { user_creatable_complete(obj, &local_err); if (local_err) { object_unparent(obj); diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c index 72b97a8bed..e3084bc04a 100644 --- a/qom/object_interfaces.c +++ b/qom/object_interfaces.c @@ -10,18 +10,15 @@ void user_creatable_complete(Object *obj, Error **errp) { - UserCreatableClass *ucc; - UserCreatable *uc = - (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE); - if (!uc) { + if (!IS_USER_CREATABLE(obj)) { return; } - ucc = USER_CREATABLE_GET_CLASS(uc); + ucc = USER_CREATABLE_GET_CLASS(obj); if (ucc->complete) { - ucc->complete(uc, errp); + ucc->complete(USER_CREATABLE(obj), errp); } }
Improve a bit code readability. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> --- include/qom/object_interfaces.h | 4 ++++ qom/object.c | 4 ++-- qom/object_interfaces.c | 9 +++------ 3 files changed, 9 insertions(+), 8 deletions(-)