From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C86508BF9; Tue, 17 Oct 2023 03:25:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from out30-98.freemail.mail.aliyun.com (out30-98.freemail.mail.aliyun.com [115.124.30.98]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 51AFF8F; Mon, 16 Oct 2023 20:25:19 -0700 (PDT) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R101e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046056;MF=xuanzhuo@linux.alibaba.com;NM=1;PH=DS;RN=13;SR=0;TI=SMTPD_---0VuLNrE7_1697513115; Received: from localhost(mailfrom:xuanzhuo@linux.alibaba.com fp:SMTPD_---0VuLNrE7_1697513115) by smtp.aliyun-inc.com; Tue, 17 Oct 2023 11:25:16 +0800 Message-ID: <1697512950.0813534-1-xuanzhuo@linux.alibaba.com> Subject: Re: [PATCH net-next v1 00/19] virtio-net: support AF_XDP zero copy Date: Tue, 17 Oct 2023 11:22:30 +0800 From: Xuan Zhuo To: Jason Wang Cc: netdev@vger.kernel.org, "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , "Michael S. Tsirkin" , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , virtualization@lists.linux-foundation.org, bpf@vger.kernel.org References: <20231016120033.26933-1-xuanzhuo@linux.alibaba.com> <1697511725.2037013-1-xuanzhuo@linux.alibaba.com> In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-9.9 required=5.0 tests=BAYES_00, ENV_AND_HDR_SPF_MATCH,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,USER_IN_DEF_SPF_WL autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: On Tue, 17 Oct 2023 11:20:41 +0800, Jason Wang wrote: > On Tue, Oct 17, 2023 at 11:11=E2=80=AFAM Xuan Zhuo wrote: > > > > On Tue, 17 Oct 2023 10:53:44 +0800, Jason Wang wr= ote: > > > On Mon, Oct 16, 2023 at 8:00=E2=80=AFPM Xuan Zhuo wrote: > > > > > > > > ## AF_XDP > > > > > > > > XDP socket(AF_XDP) is an excellent bypass kernel network framework.= The zero > > > > copy feature of xsk (XDP socket) needs to be supported by the drive= r. The > > > > performance of zero copy is very good. mlx5 and intel ixgbe already= support > > > > this feature, This patch set allows virtio-net to support xsk's zer= ocopy xmit > > > > feature. > > > > > > > > At present, we have completed some preparation: > > > > > > > > 1. vq-reset (virtio spec and kernel code) > > > > 2. virtio-core premapped dma > > > > 3. virtio-net xdp refactor > > > > > > > > So it is time for Virtio-Net to complete the support for the XDP So= cket > > > > Zerocopy. > > > > > > > > Virtio-net can not increase the queue num at will, so xsk shares th= e queue with > > > > kernel. > > > > > > > > On the other hand, Virtio-Net does not support generate interrupt f= rom driver > > > > manually, so when we wakeup tx xmit, we used some tips. If the CPU = run by TX > > > > NAPI last time is other CPUs, use IPI to wake up NAPI on the remote= CPU. If it > > > > is also the local CPU, then we wake up napi directly. > > > > > > > > This patch set includes some refactor to the virtio-net to let that= to support > > > > AF_XDP. > > > > > > > > ## performance > > > > > > > > ENV: Qemu with vhost-user(polling mode). > > > > > > > > Sockperf: https://github.com/Mellanox/sockperf > > > > I use this tool to send udp packet by kernel syscall. > > > > > > > > xmit command: sockperf tp -i 10.0.3.1 -t 1000 > > > > > > > > I write a tool that sends udp packets or recvs udp packets by AF_XD= P. > > > > > > > > | Guest APP CPU |Guest Softirq CPU | UDP PPS > > > > ------------------|---------------|------------------|------------ > > > > xmit by syscall | 100% | | 676,915 > > > > xmit by xsk | 59.1% | 100% | 5,447,168 > > > > recv by syscall | 60% | 100% | 932,288 > > > > recv by xsk | 35.7% | 100% | 3,343,168 > > > > > > Any chance we can get a testpmd result (which I guess should be better > > > than PPS above)? > > > > Do you mean testpmd + DPDK + AF_XDP? > > Yes. > > > > > Yes. This is probably better because my tool does more work. That is no= t a > > complete testing tool used by our business. > > Probably, but it would be appealing for others. Especially considering > DPDK supports AF_XDP PMD now. OK. Let me try. But could you start to review firstly? > > > > > What I noticed is that the hotspot is the driver writing virtio desc. B= ecause > > the device is in busy mode. So there is race between driver and device. > > So I modified the virtio core and lazily updated avail idx. Then pps ca= n reach > > 10,000,000. > > Care to post a draft for this? YES, I is thinking for this. But maybe that is just work for split. The packed mode has some troubles. Thanks. > > Thanks > > > > > Thanks. > > > > > > > > Thanks > > > > > > > > > > > ## maintain > > > > > > > > I am currently a reviewer for virtio-net. I commit to maintain AF_X= DP support in > > > > virtio-net. > > > > > > > > Please review. > > > > > > > > Thanks. > > > > > > > > v1: > > > > 1. remove two virtio commits. Push this patchset to net-next > > > > 2. squash "virtio_net: virtnet_poll_tx support rescheduled" to = xsk: support tx > > > > 3. fix some warnings > > > > > > > > Xuan Zhuo (19): > > > > virtio_net: rename free_old_xmit_skbs to free_old_xmit > > > > virtio_net: unify the code for recycling the xmit ptr > > > > virtio_net: independent directory > > > > virtio_net: move to virtio_net.h > > > > virtio_net: add prefix virtnet to all struct/api inside virtio_ne= t.h > > > > virtio_net: separate virtnet_rx_resize() > > > > virtio_net: separate virtnet_tx_resize() > > > > virtio_net: sq support premapped mode > > > > virtio_net: xsk: bind/unbind xsk > > > > virtio_net: xsk: prevent disable tx napi > > > > virtio_net: xsk: tx: support tx > > > > virtio_net: xsk: tx: support wakeup > > > > virtio_net: xsk: tx: virtnet_free_old_xmit() distinguishes xsk bu= ffer > > > > virtio_net: xsk: tx: virtnet_sq_free_unused_buf() check xsk buffer > > > > virtio_net: xsk: rx: introduce add_recvbuf_xsk() > > > > virtio_net: xsk: rx: introduce receive_xsk() to recv xsk buffer > > > > virtio_net: xsk: rx: virtnet_rq_free_unused_buf() check xsk buffer > > > > virtio_net: update tx timeout record > > > > virtio_net: xdp_features add NETDEV_XDP_ACT_XSK_ZEROCOPY > > > > > > > > MAINTAINERS | 2 +- > > > > drivers/net/Kconfig | 8 +- > > > > drivers/net/Makefile | 2 +- > > > > drivers/net/virtio/Kconfig | 13 + > > > > drivers/net/virtio/Makefile | 8 + > > > > drivers/net/{virtio_net.c =3D> virtio/main.c} | 652 +++++++++-----= ------ > > > > drivers/net/virtio/virtio_net.h | 359 +++++++++++ > > > > drivers/net/virtio/xsk.c | 545 ++++++++++++++++ > > > > drivers/net/virtio/xsk.h | 32 + > > > > 9 files changed, 1247 insertions(+), 374 deletions(-) > > > > create mode 100644 drivers/net/virtio/Kconfig > > > > create mode 100644 drivers/net/virtio/Makefile > > > > rename drivers/net/{virtio_net.c =3D> virtio/main.c} (91%) > > > > create mode 100644 drivers/net/virtio/virtio_net.h > > > > create mode 100644 drivers/net/virtio/xsk.c > > > > create mode 100644 drivers/net/virtio/xsk.h > > > > > > > > -- > > > > 2.32.0.3.g01195cf9f > > > > > > > > > >