From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <zhihong.wang@intel.com> Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by dpdk.org (Postfix) with ESMTP id 884BE5AB0 for <dev@dpdk.org>; Thu, 18 Aug 2016 15:44:25 +0200 (CEST) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP; 18 Aug 2016 06:44:24 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.28,539,1464678000"; d="scan'208";a="750444168" Received: from fmsmsx103.amr.corp.intel.com ([10.18.124.201]) by FMSMGA003.fm.intel.com with ESMTP; 18 Aug 2016 06:44:25 -0700 Received: from FMSMSX110.amr.corp.intel.com (10.18.116.10) by FMSMSX103.amr.corp.intel.com (10.18.124.201) with Microsoft SMTP Server (TLS) id 14.3.248.2; Thu, 18 Aug 2016 06:44:24 -0700 Received: from shsmsx151.ccr.corp.intel.com (10.239.6.50) by fmsmsx110.amr.corp.intel.com (10.18.116.10) with Microsoft SMTP Server (TLS) id 14.3.248.2; Thu, 18 Aug 2016 06:44:24 -0700 Received: from shsmsx103.ccr.corp.intel.com ([169.254.4.181]) by SHSMSX151.ccr.corp.intel.com ([169.254.3.150]) with mapi id 14.03.0248.002; Thu, 18 Aug 2016 21:44:22 +0800 From: "Wang, Zhihong" <zhihong.wang@intel.com> To: Yuanhan Liu <yuanhan.liu@linux.intel.com>, Maxime Coquelin <maxime.coquelin@redhat.com> CC: "dev@dpdk.org" <dev@dpdk.org> Thread-Topic: [dpdk-dev] [PATCH] optimize vhost enqueue Thread-Index: AQHR960YCQUsXmkhfkCfaLs++FbB76BLF3QAgAFB2ND//5IYgIAAxTew//+qXQCAAAlWgIACWM2w Date: Thu, 18 Aug 2016 13:44:21 +0000 Message-ID: <8F6C2BD409508844A0EFC19955BE0941107727A7@SHSMSX103.ccr.corp.intel.com> References: <1471319402-112998-1-git-send-email-zhihong.wang@intel.com> <bbf7f96b-81e7-1702-c055-bd231fe6fa64@redhat.com> <8F6C2BD409508844A0EFC19955BE09411077206B@SHSMSX103.ccr.corp.intel.com> <20160817023825.GO30752@yliu-dev.sh.intel.com> <8F6C2BD409508844A0EFC19955BE09411077220A@SHSMSX103.ccr.corp.intel.com> <020de331-94f0-049a-6e7d-30825faf54dd@redhat.com> <20160817095111.GQ30752@yliu-dev.sh.intel.com> In-Reply-To: <20160817095111.GQ30752@yliu-dev.sh.intel.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ctpclassification: CTP_IC x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiOThiZGZhYjgtN2MzMC00ODk2LWJiNjYtZDY0NzYxOGJlNDIyIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX0lDIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE1LjkuNi42IiwiVHJ1c3RlZExhYmVsSGFzaCI6InFHQWhVcGNCb2k2K2lQam1XQllYMlhnRVk1Y0dJOWpPK1hvdmxzTFJHanc9In0= 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] optimize vhost enqueue X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK <dev.dpdk.org> List-Unsubscribe: <http://dpdk.org/ml/options/dev>, <mailto:dev-request@dpdk.org?subject=unsubscribe> List-Archive: <http://dpdk.org/ml/archives/dev/> List-Post: <mailto:dev@dpdk.org> List-Help: <mailto:dev-request@dpdk.org?subject=help> List-Subscribe: <http://dpdk.org/ml/listinfo/dev>, <mailto:dev-request@dpdk.org?subject=subscribe> X-List-Received-Date: Thu, 18 Aug 2016 13:44:26 -0000 Thanks Maxime and Yuanhan for your review and suggestions! Please help review the v2 of this patch. > -----Original Message----- > From: Yuanhan Liu [mailto:yuanhan.liu@linux.intel.com] > Sent: Wednesday, August 17, 2016 5:51 PM > To: Maxime Coquelin <maxime.coquelin@redhat.com> > Cc: Wang, Zhihong <zhihong.wang@intel.com>; dev@dpdk.org > Subject: Re: [dpdk-dev] [PATCH] optimize vhost enqueue >=20 > On Wed, Aug 17, 2016 at 11:17:46AM +0200, Maxime Coquelin wrote: > > >>>This is something I've thought about while writing the code, the rea= son I > > >>>keep it as one function body is that: > > >>> > > >>> 1. This function is very performance sensitive, and we need full co= ntrol of > > >>> code ordering (You can compare with the current performance with > the > > >>> mrg_rxbuf feature turned on to see the difference). > > >> > > >>Will inline functions help? > > > > > > > > >Optimization in this patch actually reorganizes the code from its logi= c, > > >so it's not suitable for making separated functions. > > > > > >I'll explain this in v2. > > > > I agree with Yuanhan. > > Inline functions should not break the optimizations. > > IMHO, this is mandatory for the patch to be accepted. >=20 > Yes. >=20 > > It seems you are not the only one facing the issue: > > https://github.com/YanVugenfirer/kvm-guest-drivers-windows/issues/70 > > > > So a dedicated fix is really important. >=20 > Yes. >=20 > > > > >This patch doesn't try to fix this issue, it rewrites the logic totall= y, > > >and somehow fixes this issue. > > > > > >Do you think integrating this whole patch into the stable branch will = work? > > >Personally I think it makes more sense. > > > > No. > > We don't even know why/how it fixes the Windows issue, which would be > > the first thing to understand before integrating a fix in stable branch= . >=20 > Yes. >=20 > > > > And the stable branch is not meant for integrating such big reworks, > > it is only meant to fix bugs. >=20 > Yes. >=20 > > The risk of regressions have to be avoided as much as possible. >=20 > Yes. >=20 > --yliu