From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7DFAEC433ED for ; Tue, 6 Apr 2021 07:03:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3697861242 for ; Tue, 6 Apr 2021 07:03:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244125AbhDFHDx (ORCPT ); Tue, 6 Apr 2021 03:03:53 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:60937 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238199AbhDFHDw (ORCPT ); Tue, 6 Apr 2021 03:03:52 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617692625; 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=zxo6tmkvBefpqtp+AZkpyNAyaWzhV5s1Lu6jg16B4FI=; b=I5BSOlfpKGBjP7CgFDr42grBV/obxb9Y70vsOCKywLUJ5Qz8T2TOoxst18dCU38Uyn32tI eDigTqFDCvRHf6fcigV902uNPbS3ZCVhxZlItifpwOTK5NpbHNVkDqCd1LYhwQClX026sa FMiDSCAMni4D+tNxlOU4jeQN5j+9+N4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-24-wrmH6CO3NNCD7xUsJyGbYw-1; Tue, 06 Apr 2021 03:03:43 -0400 X-MC-Unique: wrmH6CO3NNCD7xUsJyGbYw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 298171084D68; Tue, 6 Apr 2021 07:03:40 +0000 (UTC) Received: from wangxiaodeMacBook-Air.local (ovpn-13-95.pek2.redhat.com [10.72.13.95]) by smtp.corp.redhat.com (Postfix) with ESMTP id EF1195D6DC; Tue, 6 Apr 2021 07:03:30 +0000 (UTC) Subject: Re: [PATCH net-next v3 7/8] virtio-net: poll tx call xsk zerocopy xmit To: Xuan Zhuo , netdev@vger.kernel.org Cc: "Michael S. Tsirkin" , "David S. Miller" , Jakub Kicinski , =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , Magnus Karlsson , Jonathan Lemon , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , KP Singh , virtualization@lists.linux-foundation.org, bpf@vger.kernel.org, Dust Li References: <20210331071139.15473-1-xuanzhuo@linux.alibaba.com> <20210331071139.15473-8-xuanzhuo@linux.alibaba.com> From: Jason Wang Message-ID: Date: Tue, 6 Apr 2021 15:03:29 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.9.0 MIME-Version: 1.0 In-Reply-To: <20210331071139.15473-8-xuanzhuo@linux.alibaba.com> Content-Type: text/plain; charset=gbk; format=flowed Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org ÔÚ 2021/3/31 ÏÂÎç3:11, Xuan Zhuo дµÀ: > poll tx call virtnet_xsk_run, then the data in the xsk tx queue will be > continuously consumed by napi. > > Signed-off-by: Xuan Zhuo > Reviewed-by: Dust Li I think we need squash this into patch 4, it looks more like a bug fix to me. > --- > drivers/net/virtio_net.c | 20 +++++++++++++++++--- > 1 file changed, 17 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index d7e95f55478d..fac7d0020013 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -264,6 +264,9 @@ struct padded_vnet_hdr { > char padding[4]; > }; > > +static int virtnet_xsk_run(struct send_queue *sq, struct xsk_buff_pool *pool, > + int budget, bool in_napi); > + > static bool is_xdp_frame(void *ptr) > { > return (unsigned long)ptr & VIRTIO_XDP_FLAG; > @@ -1553,7 +1556,9 @@ static int virtnet_poll_tx(struct napi_struct *napi, int budget) > struct send_queue *sq = container_of(napi, struct send_queue, napi); > struct virtnet_info *vi = sq->vq->vdev->priv; > unsigned int index = vq2txq(sq->vq); > + struct xsk_buff_pool *pool; > struct netdev_queue *txq; > + int work = 0; > > if (unlikely(is_xdp_raw_buffer_queue(vi, index))) { > /* We don't need to enable cb for XDP */ > @@ -1563,15 +1568,24 @@ static int virtnet_poll_tx(struct napi_struct *napi, int budget) > > txq = netdev_get_tx_queue(vi->dev, index); > __netif_tx_lock(txq, raw_smp_processor_id()); > - free_old_xmit_skbs(sq, true); > + rcu_read_lock(); > + pool = rcu_dereference(sq->xsk.pool); > + if (pool) { > + work = virtnet_xsk_run(sq, pool, budget, true); > + rcu_read_unlock(); > + } else { > + rcu_read_unlock(); > + free_old_xmit_skbs(sq, true); > + } > __netif_tx_unlock(txq); > > - virtqueue_napi_complete(napi, sq->vq, 0); > + if (work < budget) > + virtqueue_napi_complete(napi, sq->vq, 0); > > if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS) > netif_tx_wake_queue(txq); > > - return 0; > + return work; Need a separate patch to "fix" the budget returned by poll_tx here. Thanks > } > > static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)