From patchwork Tue Apr 18 06:53:16 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xuan Zhuo X-Patchwork-Id: 13215089 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7FA60C77B75 for ; Tue, 18 Apr 2023 06:53:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230499AbjDRGxj (ORCPT ); Tue, 18 Apr 2023 02:53:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47386 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230358AbjDRGxf (ORCPT ); Tue, 18 Apr 2023 02:53:35 -0400 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 0CF85E49; Mon, 17 Apr 2023 23:53:33 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R161e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045192;MF=xuanzhuo@linux.alibaba.com;NM=1;PH=DS;RN=13;SR=0;TI=SMTPD_---0VgOKjx6_1681800810; Received: from localhost(mailfrom:xuanzhuo@linux.alibaba.com fp:SMTPD_---0VgOKjx6_1681800810) by smtp.aliyun-inc.com; Tue, 18 Apr 2023 14:53:31 +0800 From: Xuan Zhuo To: netdev@vger.kernel.org Cc: "Michael S. Tsirkin" , Jason Wang , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , virtualization@lists.linux-foundation.org, bpf@vger.kernel.org Subject: [PATCH net-next v2 03/14] virtio_net: optimize mergeable_xdp_prepare() Date: Tue, 18 Apr 2023 14:53:16 +0800 Message-Id: <20230418065327.72281-4-xuanzhuo@linux.alibaba.com> X-Mailer: git-send-email 2.32.0.3.g01195cf9f In-Reply-To: <20230418065327.72281-1-xuanzhuo@linux.alibaba.com> References: <20230418065327.72281-1-xuanzhuo@linux.alibaba.com> MIME-Version: 1.0 X-Git-Hash: d931ac25730a Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org The previous patch, in order to facilitate review, I do not do any modification. This patch has made some optimization on the top. * remove some repeated logics in this function. * add fast check for passing without any alloc. Signed-off-by: Xuan Zhuo Acked-by: Jason Wang --- drivers/net/virtio_net.c | 29 ++++++++++++++--------------- 1 file changed, 14 insertions(+), 15 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 12559062ffb6..50dc64d80d3b 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -1192,6 +1192,11 @@ static void *mergeable_xdp_prepare(struct virtnet_info *vi, */ *frame_sz = truesize; + if (likely(headroom >= virtnet_get_headroom(vi) && + (*num_buf == 1 || xdp_prog->aux->xdp_has_frags))) { + return page_address(*page) + offset; + } + /* This happens when headroom is not enough because * of the buffer was prefilled before XDP is set. * This should only happen for the first several packets. @@ -1200,22 +1205,15 @@ static void *mergeable_xdp_prepare(struct virtnet_info *vi, * support it, and we don't want to bother users who are * using xdp normally. */ - if (!xdp_prog->aux->xdp_has_frags && - (*num_buf > 1 || headroom < virtnet_get_headroom(vi))) { + if (!xdp_prog->aux->xdp_has_frags) { /* linearize data for XDP */ xdp_page = xdp_linearize_page(rq, num_buf, *page, offset, VIRTIO_XDP_HEADROOM, len); - *frame_sz = PAGE_SIZE; - if (!xdp_page) return NULL; - offset = VIRTIO_XDP_HEADROOM; - - put_page(*page); - *page = xdp_page; - } else if (unlikely(headroom < virtnet_get_headroom(vi))) { + } else { xdp_room = SKB_DATA_ALIGN(VIRTIO_XDP_HEADROOM + sizeof(struct skb_shared_info)); if (*len + xdp_room > PAGE_SIZE) @@ -1227,14 +1225,15 @@ static void *mergeable_xdp_prepare(struct virtnet_info *vi, memcpy(page_address(xdp_page) + VIRTIO_XDP_HEADROOM, page_address(*page) + offset, *len); - *frame_sz = PAGE_SIZE; - offset = VIRTIO_XDP_HEADROOM; - - put_page(*page); - *page = xdp_page; } - return page_address(*page) + offset; + *frame_sz = PAGE_SIZE; + + put_page(*page); + + *page = xdp_page; + + return page_address(*page) + VIRTIO_XDP_HEADROOM; } static struct sk_buff *receive_mergeable(struct net_device *dev,