From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60258) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZbUPM-0002Zn-PE for qemu-devel@nongnu.org; Mon, 14 Sep 2015 10:07:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZbUPG-0002Xu-Sg for qemu-devel@nongnu.org; Mon, 14 Sep 2015 10:07:00 -0400 Received: from mail-pa0-f45.google.com ([209.85.220.45]:36313) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZbUPG-0002XQ-Mh for qemu-devel@nongnu.org; Mon, 14 Sep 2015 10:06:54 -0400 Received: by padhk3 with SMTP id hk3so145206367pad.3 for ; Mon, 14 Sep 2015 07:06:54 -0700 (PDT) References: <1442194913-26545-1-git-send-email-david@gibson.dropbear.id.au> <1442194913-26545-2-git-send-email-david@gibson.dropbear.id.au> <55F683CB.6000508@ozlabs.ru> <20150914114503.GP2547@voom.fritz.box> <55F6B989.8010900@redhat.com> From: Alexey Kardashevskiy Message-ID: <55F6D479.4010301@ozlabs.ru> Date: Tue, 15 Sep 2015 00:06:49 +1000 MIME-Version: 1.0 In-Reply-To: <55F6B989.8010900@redhat.com> Content-Type: text/plain; charset=koi8-r; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFCv2 1/2] spapr: Remove unnecessary owner field from sPAPRDRConnector List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini , David Gibson Cc: qemu-devel@nongnu.org, agraf@suse.de, qemu-ppc@nongnu.org, mdroth@linux.vnet.ibm.com, bharata@linux.vnet.ibm.com On 09/14/2015 10:11 PM, Paolo Bonzini wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA256 > > > > On 14/09/2015 13:45, David Gibson wrote: >>>> >>>> === * There is no way for a child to determine what its parent >>>> is. It is not * a bidirectional relationship. This is by >>>> design. === >>>> >>>> This part always confused me as there is "Object *parent" in >>>> the "struct Object". So there is way to determine but it must >>>> not be used? Is it debug only? >>>> >>>> Anyway, all members of the Object class are under /*< private >>>>> */ so they should not be accesses in sPAPR code, I believe. >> Ah, good point, I missed that. I guess we have to keep the owner >> field, redundant though it seems. Blech. > > I think the comment is wrong or at least inaccurate; it only applies > to the external QOM interface. Is this case external? Originally I was looking for a object_get_parent() but it is not there so I decided that the comment is correct or I just fail to understand it :) > The patch is a good idea, even though > OBJECT(x)->y traditionally is not used (instead you assign OBJECT(x) to > a different Object* variable). -- Alexey