From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Wang Subject: Re: [RFC 0/7] PMD driver for AF_XDP Date: Thu, 1 Mar 2018 15:46:13 +0800 Message-ID: References: <20180227093306.23854-1-qi.z.zhang@intel.com> <4758d934-c338-e4a6-17fa-6ed90bb141ff@redhat.com> <039ED4275CED7440929022BC67E706115315D465@SHSMSX103.ccr.corp.intel.com> <039ED4275CED7440929022BC67E706115315D47B@SHSMSX103.ccr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Cc: "Karlsson, Magnus" , "Topel, Bjorn" To: "Zhang, Qi Z" , "dev@dpdk.org" Return-path: Received: from mx1.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by dpdk.org (Postfix) with ESMTP id DFA9A4C79 for ; Thu, 1 Mar 2018 08:46:20 +0100 (CET) In-Reply-To: <039ED4275CED7440929022BC67E706115315D47B@SHSMSX103.ccr.corp.intel.com> Content-Language: en-US List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 2018年03月01日 12:20, Zhang, Qi Z wrote: > +Magnus, since a typo in my first batch in email address. > >> -----Original Message----- >> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Zhang, Qi Z >> Sent: Thursday, March 1, 2018 12:19 PM >> To: Jason Wang;dev@dpdk.org >> Cc:magnus.karlsson@intei.com; Topel, Bjorn >> Subject: Re: [dpdk-dev] [RFC 0/7] PMD driver for AF_XDP >> >> >> >>> -----Original Message----- >>> From: Jason Wang [mailto:jasowang@redhat.com] >>> Sent: Thursday, March 1, 2018 10:52 AM >>> To: Zhang, Qi Z;dev@dpdk.org >>> Cc:magnus.karlsson@intei.com; Topel, Bjorn >>> Subject: Re: [dpdk-dev] [RFC 0/7] PMD driver for AF_XDP >>> >>> >>> >>> On 2018年02月27日 17:32, Qi Zhang wrote: >>>> The RFC patches add a new PMD driver for AF_XDP which is a proposed >>>> faster version of AF_PACKET interface in Linux, see below link for >>>> detail AF_XDP introduction: >>>> https://fosdem.org/2018/schedule/event/af_xdp/ >>>> https://lwn.net/Articles/745934/ >>>> >>>> This patchset is base on v18.02. >>>> It also require a linux kernel that have below AF_XDP RFC patches be >>>> applied. >>>> https://patchwork.ozlabs.org/patch/867961/ >>>> https://patchwork.ozlabs.org/patch/867960/ >>>> https://patchwork.ozlabs.org/patch/867938/ >>>> https://patchwork.ozlabs.org/patch/867939/ >>>> https://patchwork.ozlabs.org/patch/867940/ >>>> https://patchwork.ozlabs.org/patch/867941/ >>>> https://patchwork.ozlabs.org/patch/867942/ >>>> https://patchwork.ozlabs.org/patch/867943/ >>>> https://patchwork.ozlabs.org/patch/867944/ >>>> https://patchwork.ozlabs.org/patch/867945/ >>>> https://patchwork.ozlabs.org/patch/867946/ >>>> https://patchwork.ozlabs.org/patch/867947/ >>>> https://patchwork.ozlabs.org/patch/867948/ >>>> https://patchwork.ozlabs.org/patch/867949/ >>>> https://patchwork.ozlabs.org/patch/867950/ >>>> https://patchwork.ozlabs.org/patch/867951/ >>>> https://patchwork.ozlabs.org/patch/867952/ >>>> https://patchwork.ozlabs.org/patch/867953/ >>>> https://patchwork.ozlabs.org/patch/867954/ >>>> https://patchwork.ozlabs.org/patch/867955/ >>>> https://patchwork.ozlabs.org/patch/867956/ >>>> https://patchwork.ozlabs.org/patch/867957/ >>>> https://patchwork.ozlabs.org/patch/867958/ >>>> https://patchwork.ozlabs.org/patch/867959/ >>>> >>>> There is no clean upstream target yet since kernel patch is still in >>>> RFC stage, The purpose of the patchset is just for anyone that want >>>> to eveluate af_xdp with DPDK application and get feedback for >>>> further improvement. >>>> >>>> To try with the new PMD >>>> 1. compile and install the kernel with above patches applied. >>>> 2. configure $LINUX_HEADER_DIR (dir of "make headers_install") >>>> and $TOOLS_DIR (dir at /tools) at >>> driver/net/af_xdp/Makefile >>>> before compile DPDK. >>>> 3. make sure libelf and libbpf is installed. >>>> >>>> BTW, performance test shows our PMD can reach 94%~98% of the orignal >>>> benchmark when share memory is enabled. >>> Hi: >>> >>> Looks like zero copy is not used in this series. Any plan to support that? >> Zero copy is enabled in patch 5, if a mempool passed check_mempool, it will >> be registered to af_xdp socket. >> so there will be no memcpy between mbuf and af_xdp. Aha, I see. So the zerocopy was limited to some specific use case. And if I understand it correctly, zc mode could not be used for VM. Thanks >>> If not, what's the advantage compared to vhost-net + tap + XDP_REDIRECT? >>> >>> Have you measured l2fwd performance in this case? I believe the number >>> you refer here is rxdrop (XDP_DRV) which is 11.6Mpps. >> Actually we measure the performance on rxonly / txonly / l2fwd on i40e with >> XDP_SKB and XDP_DRV_ZC >> >> Regards >> Qi >> >>> Thanks