From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wg0-f45.google.com (mail-wg0-f45.google.com [74.125.82.45]) by dpdk.org (Postfix) with ESMTP id 88F3B569A for ; Thu, 9 Jul 2015 17:52:23 +0200 (CEST) Received: by wgjx7 with SMTP id x7so227124299wgj.2 for ; Thu, 09 Jul 2015 08:52:23 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:organization :user-agent:in-reply-to:references:mime-version :content-transfer-encoding:content-type; bh=NqF75V8QsT5rRv5Fzeey73BCUcHtjU4Kq0hMaOO+yJQ=; b=YOYYkpBIzOr0iJNTKsylC4aAK+TnowvznsVk2VhAH6HROcFuEWQOegTF+8ehT8UT+m X1HPVD/ntyOFAl3S3KmwqbiXV2/i38Qz0Zm8hUXYdtrlATp1yXSg7ynKp1f8IyUREvx7 ELE8XOTNgc7++wjnyulIO+bkis5YqtZbNK2oOfvxqLQWSLxyOEfAif/CFsDt+9Xo4Mlt gFZqlEmaECoYvM6Qw1Hbsn/aTj+7/pQUFf4yi1l+kJM/48dtEnHhyTjltA7zZh89vt3q VkHapR97p1cbJ2mwFpiE5I1tm/guTtKz99e7zGp2z9AH/TAx3n4vOQRzNW8iVP1YY7aa /3ow== X-Gm-Message-State: ALoCoQmJzd0vUHFg6mAZDZOt/ZP3QgzDrTAvWGjMi5l5acxHXHCTcJ0cvJBzxyT5+FtJyZ/XM1AP X-Received: by 10.194.87.4 with SMTP id t4mr34248762wjz.84.1436457143383; Thu, 09 Jul 2015 08:52:23 -0700 (PDT) Received: from xps13.localnet (136-92-190-109.dsl.ovh.fr. [109.190.92.136]) by smtp.gmail.com with ESMTPSA id gt10sm8890863wib.20.2015.07.09.08.52.21 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 09 Jul 2015 08:52:22 -0700 (PDT) From: Thomas Monjalon To: Bruce Richardson Date: Thu, 09 Jul 2015 17:51:16 +0200 Message-ID: <2534416.XSNtN7mPxB@xps13> Organization: 6WIND User-Agent: KMail/4.14.8 (Linux/4.0.4-2-ARCH; KDE/4.14.8; x86_64; ; ) In-Reply-To: <20150708131034.GA5708@bricha3-MOBL3> References: <1435585344-26652-1-git-send-email-john.mcnamara@intel.com> <1597388.Dhvyq33s8s@xps13> <20150708131034.GA5708@bricha3-MOBL3> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Cc: dev@dpdk.org Subject: Re: [dpdk-dev] [PATCH v3 7/7] abi: announce mbuf addition for ieee1588 in DPDK 2.2 X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 09 Jul 2015 15:52:23 -0000 2015-07-08 14:10, Bruce Richardson: > On Mon, Jul 06, 2015 at 03:16:01PM +0200, Thomas Monjalon wrote: > > 2015-07-02 16:16, John McNamara: > > > --- a/doc/guides/rel_notes/abi.rst > > > +++ b/doc/guides/rel_notes/abi.rst > > > Deprecation Notices > > > ------------------- > > > + > > > +* In DPDK 2.1 the IEEE1588/802.1AS support in the i40e driver makes use of the > > > + ``udata64`` field in the mbuf to pass the timesync register index to the > > > + user. In DPDK 2.2 this will be moved to a new field in the mbuf. > > > > We need more acknowledgements for this decision, as stated here: > > http://dpdk.org/browse/dpdk/tree/doc/guides/guidelines/versioning.rst#n51 > > Why can't this new field just be added at the end of cache line 1 (the second > cache line) of the mbuf? That would avoid any ABI breakage and would mean we > can just put the change in in this release, instead of waiting. Are you sure that (because of __rte_cache_aligned) the size of the structure is never increased with this new field? Please confirm your opinion. A comment to explain ABI compatibility in the commit message of the v4 is also welcome.