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=-12.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 CC9CCC433E0 for ; Thu, 21 Jan 2021 20:38:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8C0E9239D1 for ; Thu, 21 Jan 2021 20:38:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727366AbhAUUiP (ORCPT ); Thu, 21 Jan 2021 15:38:15 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50748 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727855AbhAUHtw (ORCPT ); Thu, 21 Jan 2021 02:49:52 -0500 Received: from mail-pj1-x1035.google.com (mail-pj1-x1035.google.com [IPv6:2607:f8b0:4864:20::1035]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98344C061575; Wed, 20 Jan 2021 23:41:28 -0800 (PST) Received: by mail-pj1-x1035.google.com with SMTP id kx7so1093670pjb.2; Wed, 20 Jan 2021 23:41:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=+WSQWbxfP2pXq6KG7rxKw6Frm1tiAUnTy+aL8NH7tLg=; b=U+oUAi+6oPz7NK/UpWAYd2rzwp662I5l05vsAZctRN13kGBNBWB+wdHiMdJf4vrd2Z PAR/V91v5bSPqb8FQ0Q3KO3jHi6Sruea2oqzQr+drUyRarFTz8w6lRM+wJ78aSWWaaYt WJfWsT23QYzAIBpdgK/9BEPnIC8hL7KJAU2LF6o/zwV46NlWLn/ZVm6243cwjFV159RU m/TEkIHmEWgXyyN1DYpVdfMxPKzBCp7N2Pj4r85aO/Klg0qfgjN7B46bVXEGWjbqhXq5 tASO7vbl3rW+80m/KOOEPPn0ObUtVpnCDhTqs2eVHfMTpRct1GXQdMJ/tckQ9SyedLu6 b9Bg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=+WSQWbxfP2pXq6KG7rxKw6Frm1tiAUnTy+aL8NH7tLg=; b=tbohkIP6XbS/OzIs9XX4fHIQMkT/3ZSYBsUQXy3zR4BOTYVFxsVqtbmcm8PxevIe0t 9smtH+zSNxjf2xZhJJOevKHysWMnBakB+h1oZBK6NEdoqIy2Ycj0pGHDC40eFRFI6qgt k+5z26zQpSdG3ds/xE665fgCeW5iU/zB0LV1+2728aG/ExDoU2nKr3G1M5MXUULdRyln 3xmYpQ+5/E6Hd//bEv3IcJTkn4hEiUEXyqT9gAyFf59GbokZLEdwO+PXT3heP9EaWweD 5SqDS8YfHsczNYX1tL25Av57i6LNNM0XO6FdZbvcOhj53+Ek8fOvi7+YDcKIwv9VJMf0 a7mg== X-Gm-Message-State: AOAM531/0d2wNl3Ucw5fCxTT3QUZrV9ZYpiFCqPtQQEOuCGEY6GgR1nl v5hzQHpLbF66MlsbBi5fVzeP+zfLo5Z4aKitGgw= X-Google-Smtp-Source: ABdhPJwdys27ZARkcsj3JlP6jJ7vhfnyOXsgy7FqDh/DOuIWf5jJV+IaXEog/pbBxb3lxbAWI82s0GLKrmGAdclf+HQ= X-Received: by 2002:a17:902:7c04:b029:dc:99f2:eea4 with SMTP id x4-20020a1709027c04b02900dc99f2eea4mr13569991pll.43.1611214888029; Wed, 20 Jan 2021 23:41:28 -0800 (PST) MIME-Version: 1.0 References: <0461512be1925bece9bcda1b4924b09eaa4edd87.1611131344.git.xuanzhuo@linux.alibaba.com> <20210120135537.5184-1-alobakin@pm.me> In-Reply-To: <20210120135537.5184-1-alobakin@pm.me> From: Magnus Karlsson Date: Thu, 21 Jan 2021 08:41:17 +0100 Message-ID: Subject: Re: [PATCH net-next v2 3/3] xsk: build skb by page To: Alexander Lobakin Cc: Xuan Zhuo , "Michael S. Tsirkin" , Jason Wang , "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 , Network Development , open list Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Wed, Jan 20, 2021 at 9:29 PM Alexander Lobakin wrote: > > From: Xuan Zhuo > Date: Wed, 20 Jan 2021 16:30:56 +0800 > > > This patch is used to construct skb based on page to save memory copy > > overhead. > > > > This function is implemented based on IFF_TX_SKB_NO_LINEAR. Only the > > network card priv_flags supports IFF_TX_SKB_NO_LINEAR will use page to > > directly construct skb. If this feature is not supported, it is still > > necessary to copy data to construct skb. > > > > ---------------- Performance Testing ------------ > > > > The test environment is Aliyun ECS server. > > Test cmd: > > ``` > > xdpsock -i eth0 -t -S -s > > ``` > > > > Test result data: > > > > size 64 512 1024 1500 > > copy 1916747 1775988 1600203 1440054 > > page 1974058 1953655 1945463 1904478 > > percent 3.0% 10.0% 21.58% 32.3% > > > > Signed-off-by: Xuan Zhuo > > Reviewed-by: Dust Li > > --- > > net/xdp/xsk.c | 104 ++++++++++++++++++++++++++++++++++++++++++++++++---------- > > 1 file changed, 86 insertions(+), 18 deletions(-) > > Now I like the result, thanks! > > But Patchwork still display your series incorrectly (messages 0 and 1 > are missing). I'm concerning maintainers may not take this in such > form. Try to pass the folder's name, not folder/*.patch to > git send-email when sending, and don't use --in-reply-to when sending > a new iteration. Xuan, Please make the new submission of the patch set a v3 even though you did not change the code. Just so we can clearly see it is the new submission. > > diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c > > index 8037b04..40bac11 100644 > > --- a/net/xdp/xsk.c > > +++ b/net/xdp/xsk.c > > @@ -430,6 +430,87 @@ static void xsk_destruct_skb(struct sk_buff *skb) > > sock_wfree(skb); > > } > > > > +static struct sk_buff *xsk_build_skb_zerocopy(struct xdp_sock *xs, > > + struct xdp_desc *desc) > > +{ > > + u32 len, offset, copy, copied; > > + struct sk_buff *skb; > > + struct page *page; > > + void *buffer; > > + int err, i; > > + u64 addr; > > + > > + skb = sock_alloc_send_skb(&xs->sk, 0, 1, &err); > > + if (unlikely(!skb)) > > + return ERR_PTR(err); > > + > > + addr = desc->addr; > > + len = desc->len; > > + > > + buffer = xsk_buff_raw_get_data(xs->pool, addr); > > + offset = offset_in_page(buffer); > > + addr = buffer - xs->pool->addrs; > > + > > + for (copied = 0, i = 0; copied < len; i++) { > > + page = xs->pool->umem->pgs[addr >> PAGE_SHIFT]; > > + > > + get_page(page); > > + > > + copy = min_t(u32, PAGE_SIZE - offset, len - copied); > > + > > + skb_fill_page_desc(skb, i, page, offset, copy); > > + > > + copied += copy; > > + addr += copy; > > + offset = 0; > > + } > > + > > + skb->len += len; > > + skb->data_len += len; > > + skb->truesize += len; > > + > > + refcount_add(len, &xs->sk.sk_wmem_alloc); > > + > > + return skb; > > +} > > + > > +static struct sk_buff *xsk_build_skb(struct xdp_sock *xs, > > + struct xdp_desc *desc) > > +{ > > + struct sk_buff *skb = NULL; > > + > > + if (xs->dev->priv_flags & IFF_TX_SKB_NO_LINEAR) { > > + skb = xsk_build_skb_zerocopy(xs, desc); > > + if (IS_ERR(skb)) > > + return skb; > > + } else { > > + void *buffer; > > + u32 len; > > + int err; > > + > > + len = desc->len; > > + skb = sock_alloc_send_skb(&xs->sk, len, 1, &err); > > + if (unlikely(!skb)) > > + return ERR_PTR(err); > > + > > + skb_put(skb, len); > > + buffer = xsk_buff_raw_get_data(xs->pool, desc->addr); > > + err = skb_store_bits(skb, 0, buffer, len); > > + if (unlikely(err)) { > > + kfree_skb(skb); > > + return ERR_PTR(err); > > + } > > + } > > + > > + skb->dev = xs->dev; > > + skb->priority = xs->sk.sk_priority; > > + skb->mark = xs->sk.sk_mark; > > + skb_shinfo(skb)->destructor_arg = (void *)(long)desc->addr; > > + skb->destructor = xsk_destruct_skb; > > + > > + return skb; > > +} > > + > > static int xsk_generic_xmit(struct sock *sk) > > { > > struct xdp_sock *xs = xdp_sk(sk); > > @@ -446,43 +527,30 @@ static int xsk_generic_xmit(struct sock *sk) > > goto out; > > > > while (xskq_cons_peek_desc(xs->tx, &desc, xs->pool)) { > > - char *buffer; > > - u64 addr; > > - u32 len; > > - > > if (max_batch-- == 0) { > > err = -EAGAIN; > > goto out; > > } > > > > - len = desc.len; > > - skb = sock_alloc_send_skb(sk, len, 1, &err); > > - if (unlikely(!skb)) > > + skb = xsk_build_skb(xs, &desc); > > + if (IS_ERR(skb)) { > > + err = PTR_ERR(skb); > > goto out; > > + } > > > > - skb_put(skb, len); > > - addr = desc.addr; > > - buffer = xsk_buff_raw_get_data(xs->pool, addr); > > - err = skb_store_bits(skb, 0, buffer, len); > > /* This is the backpressure mechanism for the Tx path. > > * Reserve space in the completion queue and only proceed > > * if there is space in it. This avoids having to implement > > * any buffering in the Tx path. > > */ > > spin_lock_irqsave(&xs->pool->cq_lock, flags); > > - if (unlikely(err) || xskq_prod_reserve(xs->pool->cq)) { > > + if (xskq_prod_reserve(xs->pool->cq)) { > > spin_unlock_irqrestore(&xs->pool->cq_lock, flags); > > kfree_skb(skb); > > goto out; > > } > > spin_unlock_irqrestore(&xs->pool->cq_lock, flags); > > > > - skb->dev = xs->dev; > > - skb->priority = sk->sk_priority; > > - skb->mark = sk->sk_mark; > > - skb_shinfo(skb)->destructor_arg = (void *)(long)desc.addr; > > - skb->destructor = xsk_destruct_skb; > > - > > err = __dev_direct_xmit(skb, xs->queue_id); > > if (err == NETDEV_TX_BUSY) { > > /* Tell user-space to retry the send */ > > -- > > 1.8.3.1 > > Al >