From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:55308)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <aik@ozlabs.ru>) id 1UyibA-0005M4-P0
	for qemu-devel@nongnu.org; Mon, 15 Jul 2013 09:13:54 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <aik@ozlabs.ru>) id 1Uyib9-00046w-7K
	for qemu-devel@nongnu.org; Mon, 15 Jul 2013 09:13:52 -0400
Received: from mail-pd0-f174.google.com ([209.85.192.174]:51355)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <aik@ozlabs.ru>) id 1Uyib9-00046i-0U
	for qemu-devel@nongnu.org; Mon, 15 Jul 2013 09:13:51 -0400
Received: by mail-pd0-f174.google.com with SMTP id 10so10731564pdc.19
	for <qemu-devel@nongnu.org>; Mon, 15 Jul 2013 06:13:50 -0700 (PDT)
Message-ID: <51E3F585.4010301@ozlabs.ru>
Date: Mon, 15 Jul 2013 23:13:41 +1000
From: Alexey Kardashevskiy <aik@ozlabs.ru>
MIME-Version: 1.0
References: <1372315560-5478-1-git-send-email-aik@ozlabs.ru>
	<1372315560-5478-6-git-send-email-aik@ozlabs.ru>
	<871u78299c.fsf@codemonkey.ws> <51DB5413.8020101@ozlabs.ru>
	<CA+aC4kupAbB3LfOOYScCGUCh=zFE6ZJdHu6ErPwZP2CtOnBmgg@mail.gmail.com>
	<51DB8587.30506@ozlabs.ru> <51E3F3B7.4090000@redhat.com>
In-Reply-To: <51E3F3B7.4090000@redhat.com>
Content-Type: text/plain; charset=KOI8-R
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [PATCH 05/17] pseries: savevm support for XICS
 interrupt controller
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>, Alexander Graf <agraf@suse.de>, qemu-devel <qemu-devel@nongnu.org>, Paul Mackerras <paulus@samba.org>, Anthony Liguori <anthony@codemonkey.ws>, qemu-ppc@nongnu.org, David Gibson <david@gibson.dropbear.id.au>

On 07/15/2013 11:05 PM, Paolo Bonzini wrote:
> Il 09/07/2013 05:37, Alexey Kardashevskiy ha scritto:
>>
>> btw xics-kvm does not introduce new members but does have very different
>> .pre_save and .post_load. This actually was the whole point of splitting
>> xics into xics and xics-kvm. I cannot see how I can fix it without hacks.
>> Property's can be inherited from a parent class (?) but VMStateDescription
>> cannot.
> 
> The vmstate's pre_save and post_load functions can dispatch to a method
> in the subclass.  Again, i8259 does exactly what you want:
> 
> static void pic_dispatch_pre_save(void *opaque)
> {
>     PICCommonState *s = opaque;
>     PICCommonClass *info = PIC_COMMON_GET_CLASS(s);
> 
>     if (info->pre_save) {
>         info->pre_save(s);
>     }
> }

And this is not a hack. Hm. I do not get it. There is even INTERFACE_CLASS
defined but noone is using it. Instead you are proposing to add callbacks
called from callbacks. And this is all for not having dev==NULL in
vmstate_register()... Gosh :(


-- 
Alexey