From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f42.google.com (mail-wm0-f42.google.com [74.125.82.42]) by dpdk.org (Postfix) with ESMTP id 4717AA6A for ; Tue, 5 Apr 2016 10:38:53 +0200 (CEST) Received: by mail-wm0-f42.google.com with SMTP id f198so21623630wme.0 for ; Tue, 05 Apr 2016 01:38:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=6wind-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:organization:user-agent :in-reply-to:references:mime-version:content-transfer-encoding; bh=gFO3jPDrEyyw+Dw1Emj5J2xFP9jFKEWzTL/mYks5+w4=; b=GIPQGbae4wMrtvG99mXp+X896Gfz1N62fXw9y7RVaXTRNtMgtElBfpop41Lesbm2nT sBwssjrxmEtQocF6qvUlPNub2NSlvFw5ueP048zK52PIJnmVGy22awo0lMaYAereFEbS UDXXdUmTh1Jmiz/WeKY9dA9L7SFGICnvokWa95LNDMHgUV2Y8zc1j/zUk2DnGVlSXLTF SnUr74ajN80Cm+kD0D2tNftwnG2LW7L9yg0j0QSfi0VH16jhjEOaZLwsRKC1TI1RLXoG gL2IvU41zPR5RCzORW3aw3IHImTqEtHOUyoxIrBJycgmPEKdB9xj6Lc2ctgKRnyaciw1 5SMg== 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; bh=gFO3jPDrEyyw+Dw1Emj5J2xFP9jFKEWzTL/mYks5+w4=; b=XotBxPrbbeYT/SYSEOhgyNcawTXRSNchXKhuG0YIhIzwzI2NHzS2hA6ds4BjYWzZXo En7YCfF0jWUbn7wIn0xR3tcMi738pCohxT8GEisrMrF39Kgj/IXUmrm+9wnrUwDdglvV hu1ZJS/8thbWKBhqIcIjSAaQ/TDPZfqhvcucN2G0mbVsjOeSqwWLcGtzWcDOvCM3PkMo cK9iKs3kT24J15XKKEcpEzMyyBX2RzZLQTDll6MW9yyGFpwaQsaN/IEVaDlLNFThnWqE z1S8Pv3ufo2Q59CWrF51hVOUFSUoCChu3zXqlNdt1EcNNQcPgCjMuhyB1ayX1Ue5GcwC +uWg== X-Gm-Message-State: AD7BkJLKltV00hzJws9EJ4ACIRkmWZVFDnRNzCfK2VZJU1DGhxYKGnrKrwO+G7JuVpg1WzY6 X-Received: by 10.28.107.13 with SMTP id g13mr16740902wmc.62.1459845533085; Tue, 05 Apr 2016 01:38:53 -0700 (PDT) Received: from xps13.localnet (91.111.75.86.rev.sfr.net. [86.75.111.91]) by smtp.gmail.com with ESMTPSA id ux5sm33388637wjc.17.2016.04.05.01.38.52 (version=TLSv1/SSLv3 cipher=OTHER); Tue, 05 Apr 2016 01:38:52 -0700 (PDT) From: Thomas Monjalon To: Yuanhan Liu Cc: dev@dpdk.org, Ilya Maximets , Dyasly Sergey , Flavio Leitner , "Xie, Huawei" Date: Tue, 05 Apr 2016 10:37:13 +0200 Message-ID: <1865360.UqzrcfEKI5@xps13> Organization: 6WIND User-Agent: KMail/4.14.10 (Linux/4.1.6-1-ARCH; KDE/4.14.11; x86_64; ; ) In-Reply-To: <20160405054733.GO3080@yliu-dev.sh.intel.com> References: <1455863563-15751-1-git-send-email-i.maximets@samsung.com> <20160219070650.GS21426@yliu-dev.sh.intel.com> <20160405054733.GO3080@yliu-dev.sh.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Subject: Re: [dpdk-dev] [RFC] vhost-user public struct refactor (was Re: [PATCH RFC 2/4] vhost: make buf vector for scatter RX) local. 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: Tue, 05 Apr 2016 08:38:53 -0000 2016-04-05 13:47, Yuanhan Liu: > So, I was considering to add vhost-user Tx delayed-copy (or zero copy) > support recently, which comes to yet another ABI violation, as we need > add a new field to virtio_memory_regions struct to do guest phys addr > to host phys addr translation. You may ask, however, that why do we need > expose virtio_memory_regions struct to users at all? > > You are right, we don't have to. And here is the thing: we exposed way > too many fields (or even structures) than necessary. Say, vhost_virtqueue > struct should NOT be exposed to user at all: application just need to > tell the right queue id to locate a specific queue, and that's all. > The structure should be defined in an internal header file. With that, > we could do any changes to it we want, without worrying about that we > may offense the painful ABI rules. > > Similar changes could be done to virtio_net struct as well, just exposing > very few fields that are necessary and moving all others to an internal > structure. > > Huawei then suggested a more radical yet much cleaner one: just exposing > a virtio_net handle to application, just like the way kernel exposes an > fd to user for locating a specific file. However, it's more than an ABI > change; it's also an API change: some fields are referenced by applications, > such as flags, virt_qp_nb. We could expose some new functions to access > them though. > > I'd vote for this one, as it sounds very clean to me. This would also > solve the block issue of this patch. Though it would break OVS, I'm thinking > that'd be okay, as OVS has dependence on DPDK version: what we need to > do is just to send few patches to OVS, and let it points to next release, > say DPDK v16.07. Flavio, please correct me if I'm wrong. > > Thoughts/comments? Do you plan to send a deprecation notice to change API in 16.07?