From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by dpdk.org (Postfix) with ESMTP id 161C22B8F for ; Wed, 7 Dec 2016 07:12:03 +0100 (CET) Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga103.jf.intel.com with ESMTP; 06 Dec 2016 22:12:02 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.33,310,1477983600"; d="scan'208";a="39654941" Received: from fmsmsx107.amr.corp.intel.com ([10.18.124.205]) by orsmga005.jf.intel.com with ESMTP; 06 Dec 2016 22:12:02 -0800 Received: from fmsmsx112.amr.corp.intel.com (10.18.116.6) by fmsmsx107.amr.corp.intel.com (10.18.124.205) with Microsoft SMTP Server (TLS) id 14.3.248.2; Tue, 6 Dec 2016 22:12:02 -0800 Received: from shsmsx104.ccr.corp.intel.com (10.239.4.70) by FMSMSX112.amr.corp.intel.com (10.18.116.6) with Microsoft SMTP Server (TLS) id 14.3.248.2; Tue, 6 Dec 2016 22:12:02 -0800 Received: from shsmsx103.ccr.corp.intel.com ([169.254.4.96]) by SHSMSX104.ccr.corp.intel.com ([169.254.5.142]) with mapi id 14.03.0248.002; Wed, 7 Dec 2016 14:12:00 +0800 From: "Wang, Zhihong" To: Yuanhan Liu CC: "dev@dpdk.org" , Thomas Monjalon Thread-Topic: [PATCH] vhost: optimize vhost memcpy Thread-Index: AQHSTHYyWBpmyoksL0mYHHQwaEW9IaD4g7oAgACkvPD//3+QgIADX0Ig Date: Wed, 7 Dec 2016 06:11:59 +0000 Message-ID: <8F6C2BD409508844A0EFC19955BE09414E8007DD@SHSMSX103.ccr.corp.intel.com> References: <1480641582-56186-1-git-send-email-zhihong.wang@intel.com> <20161205082714.GJ24403@yliu-dev.sh.intel.com> <8F6C2BD409508844A0EFC19955BE09414E7FF22D@SHSMSX103.ccr.corp.intel.com> <20161205103709.GL24403@yliu-dev.sh.intel.com> In-Reply-To: <20161205103709.GL24403@yliu-dev.sh.intel.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH] vhost: optimize vhost memcpy X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 07 Dec 2016 06:12:04 -0000 > -----Original Message----- > From: Yuanhan Liu [mailto:yuanhan.liu@linux.intel.com] > Sent: Monday, December 5, 2016 6:37 PM > To: Wang, Zhihong > Cc: dev@dpdk.org; Thomas Monjalon > Subject: Re: [PATCH] vhost: optimize vhost memcpy >=20 > On Mon, Dec 05, 2016 at 10:27:00AM +0000, Wang, Zhihong wrote: > > > I like this function a lot, since it's really simple and straightforw= ard! > > > Moreover, it performs better. > > > > > > But, I don't quite like how this function is proposed: > > > > > > - rte_movX are more like internal help functions that should be used = only > > > in corresponding rte_memcpy.h file. > > > > > > - It's a good optimization, however, it will not benefit for other us= e > > > cases, though vhost is the most typical case here. > > > > > > - The optimization proves to be good for X86, but think there is no > > > guarantee it may behave well for other platforms, say ARM. > > > > > > I still would suggest you to go this way: move this function into x86= 's > > > rte_memcpy.h and call it when the data is well aligned. > > > > > > Do you mean to add something like rte_memcpy_aligned() in > > lib/librte_eal/common/include/generic/rte_memcpy.h? >=20 > Yes, but this one is not supposed to be exported as a public API. > It should be called inside rte_memcpy (when data is well aligned). > In this way, only rte_memcpy is exposed, and nothing else should > be changed. Yes I agree this is a better way to introduce this patch, I'll send out v2. >=20 > --yliu > > > > I thought of this way before, and didn't choose it because it requires > > changes in eal. But it would be a clean solution, I'd certainly like > > to implement it this way if people are okay with it. > > > > > > Thanks > > Zhihong > > > > > > > > > > --yliu