From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 5134E42C5C; Thu, 8 Jun 2023 11:17:29 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id CF5ED406B5; Thu, 8 Jun 2023 11:17:28 +0200 (CEST) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by mails.dpdk.org (Postfix) with ESMTP id 88C8B40042 for ; Thu, 8 Jun 2023 11:17:27 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1686215846; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=0XA915bOc0Q46BwN7dDLlG3FSAvHItm9lqii8UH3/2U=; b=TvGY5g1oAtSdl3lTqXvbHu3o9AJl69XhdNlqEQmqaK9/koKo5KbSAdQ33W06E4DANqKXaF XCXzd1KrV9G2KNwweuLSzkAzcTEGZeE3TCHhsoyuXKWOnvGIvbAQXwuUi+eH5hjk3MbN2T RKeCSW0xpaNH17qga8dOr7WB9KPbMR0= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-34-fjDcUJ7PNT6jhE9TRzPfxQ-1; Thu, 08 Jun 2023 05:17:23 -0400 X-MC-Unique: fjDcUJ7PNT6jhE9TRzPfxQ-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 4E9D28028B2; Thu, 8 Jun 2023 09:17:23 +0000 (UTC) Received: from [10.39.208.25] (unknown [10.39.208.25]) by smtp.corp.redhat.com (Postfix) with ESMTPS id CFCB2C0004B; Thu, 8 Jun 2023 09:17:20 +0000 (UTC) Message-ID: <088c44c5-0b01-f519-dff7-004f50d68573@redhat.com> Date: Thu, 8 Jun 2023 11:17:19 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.10.0 To: David Marchand Cc: dev@dpdk.org, chenbo.xia@intel.com, mkp@redhat.com, fbl@redhat.com, jasowang@redhat.com, cunming.liang@intel.com, xieyongji@bytedance.com, echaudro@redhat.com, eperezma@redhat.com, amorenoz@redhat.com, lulu@redhat.com References: <20230606081852.71003-1-maxime.coquelin@redhat.com> From: Maxime Coquelin Subject: Re: [PATCH v5 00/26] Add VDUSE support to Vhost library In-Reply-To: X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org On 6/7/23 10:05, David Marchand wrote: > On Tue, Jun 6, 2023 at 10:19 AM Maxime Coquelin > wrote: >> >> This series introduces a new type of backend, VDUSE, >> to the Vhost library. >> >> VDUSE stands for vDPA device in Userspace, it enables >> implementing a Virtio device in userspace and have it >> attached to the Kernel vDPA bus. >> >> Once attached to the vDPA bus, it can be used either by >> Kernel Virtio drivers, like virtio-net in our case, via >> the virtio-vdpa driver. Doing that, the device is visible >> to the Kernel networking stack and is exposed to userspace >> as a regular netdev. >> >> It can also be exposed to userspace thanks to the >> vhost-vdpa driver, via a vhost-vdpa chardev that can be >> passed to QEMU or Virtio-user PMD. >> >> While VDUSE support is already available in upstream >> Kernel, a couple of patches are required to support >> network device type: >> >> https://gitlab.com/mcoquelin/linux/-/tree/vduse_networking_rfc >> >> In order to attach the created VDUSE device to the vDPA >> bus, a recent iproute2 version containing the vdpa tool is >> required. >> >> Benchmark results: >> ================== >> >> On this v2, PVP reference benchmark has been run & compared with >> Vhost-user. >> >> When doing macswap forwarding in the worload, no difference is seen. >> When doing io forwarding in the workload, we see 4% performance >> degradation with VDUSE, comapred to Vhost-user/Virtio-user. It is >> explained by the use of the IOTLB layer in the Vhost-library when using >> VDUSE, whereas Vhost-user/Virtio-user does not make use of it. >> >> Usage: >> ====== >> >> 1. Probe required Kernel modules >> # modprobe vdpa >> # modprobe vduse >> # modprobe virtio-vdpa >> >> 2. Build (require vduse kernel headers to be available) >> # meson build >> # ninja -C build >> >> 3. Create a VDUSE device (vduse0) using Vhost PMD with >> testpmd (with 4 queue pairs in this example) >> # ./build/app/dpdk-testpmd --no-pci --vdev=net_vhost0,iface=/dev/vduse/vduse0,queues=4 --log-level=*:9 -- -i --txq=4 --rxq=4 > > 9 is a nice but undefined value. 8 is enough. > In general, I prefer "human readable" strings, like *:debug ;-). > > >> >> 4. Attach the VDUSE device to the vDPA bus >> # vdpa dev add name vduse0 mgmtdev vduse >> => The virtio-net netdev shows up (eth0 here) >> # ip l show eth0 >> 21: eth0: mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000 >> link/ether c2:73:ea:a7:68:6d brd ff:ff:ff:ff:ff:ff >> >> 5. Start/stop traffic in testpmd >> testpmd> start >> testpmd> show port stats 0 >> ######################## NIC statistics for port 0 ######################## >> RX-packets: 11 RX-missed: 0 RX-bytes: 1482 >> RX-errors: 0 >> RX-nombuf: 0 >> TX-packets: 1 TX-errors: 0 TX-bytes: 62 >> >> Throughput (since last show) >> Rx-pps: 0 Rx-bps: 0 >> Tx-pps: 0 Tx-bps: 0 >> ############################################################################ >> testpmd> stop >> >> 6. Detach the VDUSE device from the vDPA bus >> # vdpa dev del vduse0 >> >> 7. Quit testpmd >> testpmd> quit >> >> Known issues & remaining work: >> ============================== >> - Fix issue in FD manager (still polling while FD has been removed) >> - Add Netlink support in Vhost library >> - Support device reconnection >> -> a temporary patch to support reconnection via a tmpfs file is available, >> upstream solution would be in-kernel and is being developed. >> -> https://gitlab.com/mcoquelin/dpdk-next-virtio/-/commit/5ad06ce14159a9ce36ee168dd13ef389cec91137 >> - Support packed ring >> - Provide more performance benchmark results > > We are missing a reference to the kernel patches required to have > vduse accept net devices. Right, I mention it in the cover letter, but it should be in the release note also. I propose to append this to the release note: "While VDUSE support is already available in upstream Kernel, a couple of patches are required to support network device type, which are being upstreamed: https://lore.kernel.org/all/20230419134329.346825-1-maxime.coquelin@redhat.com/" Does that sound good to you? Thanks, Maxime > > I had played with the patches at v1 and it was working ok. > I did not review in depth the latest revisions, but I followed your > series from the PoC/start. > Overall, the series lgtm. > > For the series, > Acked-by: David Marchand > >