Re: [Qemu-devel] Re: [PATCH 1/7] Add support for generic notifier lists

[Avi Kivity <avi@redhat.com>]

On 03/11/2010 04:36 PM, Paolo Bonzini wrote:
> On 03/11/2010 02:42 PM, Avi Kivity wrote:
>> On 03/11/2010 03:25 PM, Paolo Bonzini wrote:
>>> I didn't understand the advantage of making QEMUNotifier a
>>> struct. Instead of using container_of, reusing QEMUBHFunc (renamed to
>>> QEMUCallbackFunc maybe?) in QEMUNotifierNode [...]
>>> seems cleaner. You would place the QEMUNotifierNode in VncState in
>>> order to do the removal later.
>>
>> I disagree. container_of() is both a little more type safe, and removes
>> the need for an extra pointer and memory object.
> > The caller will almost always have an object in which to embed the
> > notifier, best to make use of it.
>
> It doesn't remove the need for an extra memory object.  Anthony's 
> design embeds the Notifier but not the NotifierNode.  Indeed, my 
> design does have an extra pointer (in the NotifierNode, which grows 
> from 3 to 4 words).

Right.  Well, it should.

> I still don't like container_of much, but maybe I'll grow my 
> appreciation of it with time. :-)

Or grow your dislike of void pointers.

-- 
error compiling committee.c: too many arguments to function