From patchwork Thu Aug 3 14:04:36 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?b?6buE5p2w?= X-Patchwork-Id: 13340153 X-Patchwork-Delegate: kuba@kernel.org 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 6F74121D57 for ; Thu, 3 Aug 2023 14:07:13 +0000 (UTC) Received: from mail-pl1-x631.google.com (mail-pl1-x631.google.com [IPv6:2607:f8b0:4864:20::631]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ACD53212D for ; Thu, 3 Aug 2023 07:07:08 -0700 (PDT) Received: by mail-pl1-x631.google.com with SMTP id d9443c01a7336-1bb893e6365so6855305ad.2 for ; Thu, 03 Aug 2023 07:07:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1691071628; x=1691676428; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=/2IExsisHLl5wetq8sgZJvv6YFTcLdIhC4TMC2ESGVY=; b=Oo5SDTLnzyXY8qDJYDdgxiSm5KInG31WNp+6s7Aw/7vgUIpls7XV7PDYHeze+UBg5n DNl2lunWdtdOaDHXuIxE5JrJyhPZkrGSa5Td1Oqf49qpwWw8PUrIhrB7fyBHyv9odtE/ 2qhsRMSNlJy/L5ER8K/Vh3MdsTTXMR3Gnygwt5BAmPJvMOF3dflvGX+gQaOJXTqq16QM P5ltuB+AVoHAG8A95Q946y5BIfsKc/I92jLgMKQ0AYzhnBfHhIGGNmOqSujdFbxrxmja ioZjmD0Md1lh9M3POXnCgEhPxjLWOm1sgM3OhCN/Kk0TToqHwyEuF4xyR9Y7y+KH8Otp jFCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691071628; x=1691676428; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=/2IExsisHLl5wetq8sgZJvv6YFTcLdIhC4TMC2ESGVY=; b=CQn9CVMsLPP657foD1P8IpRueZybwHq3wQHSA9ZGnZjrPy72Ob4zaaFCuSs9exR3+g Yr2fEu1K+j96Bll5jJ047r3lV7N2TF/AbBTPIVLzXcCvuQd07hywRn0whtTEDBr9FapZ TB/c65baTq02358v7NdhoP6LQq1XlyfIszYIEKdwMsY4twmj2Zxzzb7c6y9vfJngunuH jGQENZ9+lx4+jW2Ktba7rUDlnN6ZqkoIN7W+2z5WByKIFXC/e/Y1hZt0bryEPn/HaWYX yZS3lzUJSI3mjUTJWC9445obAvP4yRfKcUYVvI9SaYjOaC3PditAfY0tLxU9DlnJTYvk VBtQ== X-Gm-Message-State: ABy/qLYDfGq6eTSUS8ERP/SRMTKYvA9KQU8BrOb88WHyfU/C9DW7eHoE MI2wniszGbMYTDxVvQhmXIUxjc62mBn5l7c4dCV+zw== X-Google-Smtp-Source: APBJJlGM8RoAE6cD3VioW4CUSFeL+hHwLfuzL1GJ4xLv4TINBL02vq+XY8MB4/1oSJTMpPWFx/47lg== X-Received: by 2002:a17:902:ea08:b0:1bb:893e:5df5 with SMTP id s8-20020a170902ea0800b001bb893e5df5mr22673401plg.34.1691071627752; Thu, 03 Aug 2023 07:07:07 -0700 (PDT) Received: from C02FG34NMD6R.bytedance.net ([2001:c10:ff04:0:1000::8]) by smtp.gmail.com with ESMTPSA id ji11-20020a170903324b00b001b8a897cd26sm14367485plb.195.2023.08.03.07.07.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 03 Aug 2023 07:07:07 -0700 (PDT) From: "huangjie.albert" To: davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com Cc: "huangjie.albert" , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= , Magnus Karlsson , Maciej Fijalkowski , Jonathan Lemon , Pavel Begunkov , Yunsheng Lin , Kees Cook , Richard Gobert , netdev@vger.kernel.org (open list:NETWORKING DRIVERS), linux-kernel@vger.kernel.org (open list), bpf@vger.kernel.org (open list:XDP (eXpress Data Path)) Subject: [RFC Optimizing veth xsk performance 10/10] veth: af_xdp tx batch support for ipv4 udp Date: Thu, 3 Aug 2023 22:04:36 +0800 Message-Id: <20230803140441.53596-11-huangjie.albert@bytedance.com> X-Mailer: git-send-email 2.37.1 (Apple Git-137.1) In-Reply-To: <20230803140441.53596-1-huangjie.albert@bytedance.com> References: <20230803140441.53596-1-huangjie.albert@bytedance.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_BLOCKED, SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: kuba@kernel.org X-Patchwork-State: RFC A typical topology is shown below: veth<--------veth-peer 1 | |2 | bridge<------->eth0(such as mlnx5 NIC) If you use af_xdp to send packets from veth to a physical NIC, it needs to go through some software paths, so we can refer to the implementation of kernel GSO. When af_xdp sends packets out from veth, consider aggregating packets and send a large packet from the veth virtual NIC to the physical NIC. performance:(test weth libxdp lib) AF_XDP without batch : 480 Kpps (with ksoftirqd 100% cpu) AF_XDP with batch : 1.5 Mpps (with ksoftirqd 15% cpu) With af_xdp batch, the libxdp user-space program reaches a bottleneck. Therefore, the softirq did not reach the limit. Signed-off-by: huangjie.albert --- drivers/net/veth.c | 264 ++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 249 insertions(+), 15 deletions(-) diff --git a/drivers/net/veth.c b/drivers/net/veth.c index e4f1a8345f42..b0dbd21089c8 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -29,6 +29,7 @@ #include #include #include +#include #define DRV_NAME "veth" #define DRV_VERSION "1.0" @@ -103,6 +104,18 @@ struct veth_xdp_tx_bq { unsigned int count; }; +struct veth_gso_tuple { + __u8 protocol; + __be32 saddr; + __be32 daddr; + __be16 source; + __be16 dest; + __be16 gso_size; + __be16 gso_segs; + bool gso_enable; + bool gso_flush; +}; + struct veth_seg_info { u32 segs; u64 desc[] ____cacheline_aligned_in_smp; @@ -650,6 +663,84 @@ static int veth_xdp_tx(struct veth_rq *rq, struct xdp_buff *xdp, return 0; } +static struct sk_buff *veth_build_gso_head_skb(struct net_device *dev, char *buff, u32 tot_len, u32 headroom, u32 iph_len, u32 th_len) +{ + struct sk_buff *skb = NULL; + int err = 0; + + skb = alloc_skb(tot_len, GFP_KERNEL); + if (unlikely(!skb)) + return NULL; + + /* header room contains the eth header */ + skb_reserve(skb, headroom - ETH_HLEN); + + skb_put(skb, ETH_HLEN + iph_len + th_len); + + skb_shinfo(skb)->gso_segs = 0; + + err = skb_store_bits(skb, 0, buff, ETH_HLEN + iph_len + th_len); + if (unlikely(err)) { + kfree_skb(skb); + return NULL; + } + + skb->protocol = eth_type_trans(skb, dev); + skb->network_header = skb->mac_header + ETH_HLEN; + skb->transport_header = skb->network_header + iph_len; + skb->ip_summed = CHECKSUM_PARTIAL; + + return skb; +} + +static inline bool gso_segment_match(struct veth_gso_tuple *gso_tuple, struct iphdr *iph, struct udphdr *udph) +{ + if (gso_tuple->protocol == iph->protocol && + gso_tuple->saddr == iph->saddr && + gso_tuple->daddr == iph->daddr && + gso_tuple->source == udph->source && + gso_tuple->dest == udph->dest && + gso_tuple->gso_size == ntohs(udph->len)) + { + gso_tuple->gso_flush = false; + return true; + } else { + gso_tuple->gso_flush = true; + return false; + } +} + +static inline void gso_tuple_init(struct veth_gso_tuple *gso_tuple, struct iphdr *iph, struct udphdr *udph) +{ + gso_tuple->protocol = iph->protocol; + gso_tuple->saddr = iph->saddr; + gso_tuple->daddr = iph->daddr; + gso_tuple->source = udph->source; + gso_tuple->dest = udph->dest; + gso_tuple->gso_flush = false; + gso_tuple->gso_size = ntohs(udph->len); + gso_tuple->gso_segs = 0; +} + +/* only ipv4 udp support gso now */ +static inline bool ip_hdr_gso_check(unsigned char *buff, u32 len) +{ + struct iphdr *iph; + + if (len <= (ETH_HLEN + sizeof(*iph))) + return false; + + iph = (struct iphdr *)(buff + ETH_HLEN); + + /* + * check for ip headers, if the data support gso + */ + if (iph->ihl < 5 || iph->version != 4 || len < (iph->ihl * 4 + ETH_HLEN) || iph->protocol != IPPROTO_UDP) + return false; + + return true; +} + static struct sk_buff *veth_build_skb(void *head, int headroom, int len, int buflen) { @@ -686,8 +777,8 @@ static void veth_xsk_destruct_skb(struct sk_buff *skb) skb_shinfo(skb)->destructor_arg_xsk_pool = NULL; } -static struct sk_buff *veth_build_skb_zerocopy(struct net_device *dev, struct xsk_buff_pool *pool, - struct xdp_desc *desc) +static struct sk_buff *veth_build_skb_zerocopy_normal(struct net_device *dev, + struct xsk_buff_pool *pool, struct xdp_desc *desc) { struct veth_seg_info *seg_info; struct sk_buff *skb; @@ -698,45 +789,133 @@ static struct sk_buff *veth_build_skb_zerocopy(struct net_device *dev, struct xs int headroom; u64 addr; u32 index; - addr = desc->addr; len = desc->len; buffer = xsk_buff_raw_get_data(pool, addr); ts = pool->unaligned ? len : pool->chunk_size; - headroom = offset_in_page(buffer); - /* offset in umem pool buffer */ addr = buffer - pool->addrs; - /* get the page of the desc */ page = pool->umem->pgs[addr >> PAGE_SHIFT]; - /* in order to avoid to get freed by kfree_skb */ get_page(page); - hard_start = page_to_virt(page); - skb = veth_build_skb(hard_start, headroom, len, ts); seg_info = (struct veth_seg_info *)kmalloc(struct_size(seg_info, desc, MAX_SKB_FRAGS), GFP_KERNEL); if (!seg_info) { printk("here must to deal with\n"); } - /* later we will support gso for this */ index = skb_shinfo(skb)->gso_segs; seg_info->desc[index] = desc->addr; seg_info->segs = ++index; - skb->truesize += ts; skb->dev = dev; skb_shinfo(skb)->destructor_arg = (void *)(long)seg_info; skb_shinfo(skb)->destructor_arg_xsk_pool = (void *)(long)pool; skb->destructor = veth_xsk_destruct_skb; - /* set the mac header */ skb->protocol = eth_type_trans(skb, dev); + /* to do, add skb to sock. may be there is no need to do for this + * refcount_add(ts, &xs->sk.sk_wmem_alloc); + */ + return skb; +} + +static struct sk_buff *veth_build_skb_zerocopy_gso(struct net_device *dev, struct xsk_buff_pool *pool, + struct xdp_desc *desc, struct veth_gso_tuple *gso_tuple, struct sk_buff *prev_skb) +{ + u32 hr, len, ts, index, iph_len, th_len, data_offset, data_len, tot_len; + struct veth_seg_info *seg_info; + void *buffer; + struct udphdr *udph; + struct iphdr *iph; + struct sk_buff *skb; + struct page *page; + int hh_len = 0; + u64 addr; + + addr = desc->addr; + len = desc->len; + + /* l2 reserved len */ + hh_len = LL_RESERVED_SPACE(dev); + hr = max(NET_SKB_PAD, L1_CACHE_ALIGN(hh_len)); + + /* data points to eth header */ + buffer = (unsigned char *)xsk_buff_raw_get_data(pool, addr); + + iph = (struct iphdr *)(buffer + ETH_HLEN); + iph_len = iph->ihl * 4; + + udph = (struct udphdr *)(buffer + ETH_HLEN + iph_len); + th_len = sizeof(struct udphdr); + + if (gso_tuple->gso_flush) + gso_tuple_init(gso_tuple, iph, udph); + + ts = pool->unaligned ? len : pool->chunk_size; + + data_offset = offset_in_page(buffer) + ETH_HLEN + iph_len + th_len; + data_len = len - (ETH_HLEN + iph_len + th_len); + + /* head is null or this is a new 5 tuple */ + if (NULL == prev_skb || !gso_segment_match(gso_tuple, iph, udph)) { + tot_len = hr + iph_len + th_len; + skb = veth_build_gso_head_skb(dev, buffer, tot_len, hr, iph_len, th_len); + if (!skb) { + /* to do: handle here for skb */ + return NULL; + } + + /* store information for gso */ + seg_info = (struct veth_seg_info *)kmalloc(struct_size(seg_info, desc, MAX_SKB_FRAGS), GFP_KERNEL); + if (!seg_info) { + /* to do */ + kfree_skb(skb); + return NULL; + } + } else { + skb = prev_skb; + skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4 | SKB_GSO_PARTIAL; + skb_shinfo(skb)->gso_size = data_len; + skb->ip_summed = CHECKSUM_PARTIAL; + + /* max segment is MAX_SKB_FRAGS */ + if(skb_shinfo(skb)->gso_segs >= MAX_SKB_FRAGS - 1) { + gso_tuple->gso_flush = true; + } + seg_info = (struct veth_seg_info *)skb_shinfo(skb)->destructor_arg; + } + + /* offset in umem pool buffer */ + addr = buffer - pool->addrs; + + /* get the page of the desc */ + page = pool->umem->pgs[addr >> PAGE_SHIFT]; + + /* in order to avoid to get freed by kfree_skb */ + get_page(page); + + /* desc.data can not hold in two */ + skb_fill_page_desc(skb, skb_shinfo(skb)->gso_segs, page, data_offset, data_len); + + skb->len += data_len; + skb->data_len += data_len; + skb->truesize += ts; + skb->dev = dev; + + /* later we will support gso for this */ + index = skb_shinfo(skb)->gso_segs; + seg_info->desc[index] = desc->addr; + seg_info->segs = ++index; + skb_shinfo(skb)->gso_segs++; + + skb_shinfo(skb)->destructor_arg = (void *)(long)seg_info; + skb_shinfo(skb)->destructor_arg_xsk_pool = (void *)(long)pool; + skb->destructor = veth_xsk_destruct_skb; /* to do, add skb to sock. may be there is no need to do for this * refcount_add(ts, &xs->sk.sk_wmem_alloc); @@ -744,6 +923,22 @@ static struct sk_buff *veth_build_skb_zerocopy(struct net_device *dev, struct xs return skb; } +static inline struct sk_buff *veth_build_skb_zerocopy(struct net_device *dev, struct xsk_buff_pool *pool, + struct xdp_desc *desc, struct veth_gso_tuple *gso_tuple, struct sk_buff *prev_skb) +{ + void *buffer; + + buffer = xsk_buff_raw_get_data(pool, desc->addr); + if (ip_hdr_gso_check(buffer, desc->len)) { + gso_tuple->gso_enable = true; + return veth_build_skb_zerocopy_gso(dev, pool, desc, gso_tuple, prev_skb); + } else { + gso_tuple->gso_flush = false; + gso_tuple->gso_enable = false; + return veth_build_skb_zerocopy_normal(dev, pool, desc); + } +} + static struct xdp_frame *veth_xdp_rcv_one(struct veth_rq *rq, struct xdp_frame *frame, struct veth_xdp_tx_bq *bq, @@ -1176,16 +1371,33 @@ static inline bool buffer_in_page(void *buffer, u32 len) } } +static inline void veth_skb_gso_check_update(struct sk_buff *skb) +{ + struct iphdr *iph = ip_hdr(skb); + struct udphdr *uh = udp_hdr(skb); + int ip_tot_len = skb->len; + int udp_len = skb->len - (skb->transport_header - skb->network_header); + iph->tot_len = htons(ip_tot_len); + ip_send_check(iph); + uh->len = htons(udp_len); + uh->check = 0; + + /* udp4 checksum update */ + udp4_hwcsum(skb, iph->saddr, iph->daddr); +} + static int veth_xsk_tx_xmit(struct veth_sq *sq, struct xsk_buff_pool *xsk_pool, int budget) { struct veth_priv *priv, *peer_priv; struct net_device *dev, *peer_dev; + struct veth_gso_tuple gso_tuple; struct veth_rq *peer_rq; struct veth_stats peer_stats = {}; struct veth_stats stats = {}; struct veth_xdp_tx_bq bq; struct xdp_desc desc; void *xdpf; + struct sk_buff *prev_skb = NULL; struct sk_buff *skb = NULL; bool zc = xsk_pool->umem->zc; u32 xsk_headroom = xsk_pool->headroom; @@ -1200,6 +1412,8 @@ static int veth_xsk_tx_xmit(struct veth_sq *sq, struct xsk_buff_pool *xsk_pool, /* todo: queue index must set before this */ peer_rq = &peer_priv->rq[sq->queue_index]; + memset(&gso_tuple, 0, sizeof(gso_tuple)); + /* set xsk wake up flag, to do: where to disable */ if (xsk_uses_need_wakeup(xsk_pool)) xsk_set_tx_need_wakeup(xsk_pool); @@ -1279,12 +1493,26 @@ static int veth_xsk_tx_xmit(struct veth_sq *sq, struct xsk_buff_pool *xsk_pool, /* no need to copy address for af+xdp */ p_frame = veth_xdp_rcv_one(peer_rq, p_frame, &bq, &peer_stats); if (p_frame) { - skb = veth_build_skb_zerocopy(peer_dev, xsk_pool, &desc); - if (skb) { + skb = veth_build_skb_zerocopy(peer_dev, xsk_pool, &desc, &gso_tuple, prev_skb); + if (!gso_tuple.gso_enable) { napi_gro_receive(&peer_rq->xdp_napi, skb); skb = NULL; } else { - xsk_tx_completed_addr(xsk_pool, desc.addr); + if (prev_skb && gso_tuple.gso_flush) { + veth_skb_gso_check_update(prev_skb); + napi_gro_receive(&peer_rq->xdp_napi, prev_skb); + + if (prev_skb == skb) { + skb = NULL; + prev_skb = NULL; + } else { + prev_skb = skb; + } + } else if (NULL == skb){ + xsk_tx_completed_addr(xsk_pool, desc.addr); + } else { + prev_skb = skb; + } } } } else { @@ -1308,6 +1536,12 @@ static int veth_xsk_tx_xmit(struct veth_sq *sq, struct xsk_buff_pool *xsk_pool, done++; } + /* gso skb */ + if (NULL!=skb) { + veth_skb_gso_check_update(skb); + napi_gro_receive(&peer_rq->xdp_napi, skb); + } + /* release, move consumer，and wakeup the producer */ if (done) { napi_schedule(&peer_rq->xdp_napi);