From patchwork Mon Feb 15 15:27:45 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 383202 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=-18.8 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, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT 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 7A57EC433E9 for ; Mon, 15 Feb 2021 15:43:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4CD1164E8C for ; Mon, 15 Feb 2021 15:43:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231367AbhBOPmo (ORCPT ); Mon, 15 Feb 2021 10:42:44 -0500 Received: from mail.kernel.org ([198.145.29.99]:50210 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230392AbhBOPiL (ORCPT ); Mon, 15 Feb 2021 10:38:11 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id C60A664EF1; Mon, 15 Feb 2021 15:34:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1613403268; bh=bZA6qMxGaBqMadWmdQSrmd9KSoH9VnCZsx1IowzvLZ0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=A0gMubGA9fM09y54Rr9AE2B7v3wcPCyUr5nG3SgI2mHOjAsF93TVxcv4a5mmejffQ 3kq9Cd2eMFZM+Vk9t8WAtJsyJjWaWHbUoVHTYL11GMzxH7UbX9sc370qDgWOB5MiKX zZexcx8QmWFGnYVuVPZ2Jf+BaKuPkLfPr96OIXmE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , Jian Yang , Maxim Mikityanskiy , Saeed Mahameed , Edward Cree , Alexander Lobakin , Jakub Kicinski , John Sperbeck Subject: [PATCH 5.10 092/104] net: gro: do not keep too many GRO packets in napi->rx_list Date: Mon, 15 Feb 2021 16:27:45 +0100 Message-Id: <20210215152722.427768568@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210215152719.459796636@linuxfoundation.org> References: <20210215152719.459796636@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eric Dumazet commit 8dc1c444df193701910f5e80b5d4caaf705a8fb0 upstream. Commit c80794323e82 ("net: Fix packet reordering caused by GRO and listified RX cooperation") had the unfortunate effect of adding latencies in common workloads. Before the patch, GRO packets were immediately passed to upper stacks. After the patch, we can accumulate quite a lot of GRO packets (depdending on NAPI budget). My fix is counting in napi->rx_count number of segments instead of number of logical packets. Fixes: c80794323e82 ("net: Fix packet reordering caused by GRO and listified RX cooperation") Signed-off-by: Eric Dumazet Bisected-by: John Sperbeck Tested-by: Jian Yang Cc: Maxim Mikityanskiy Reviewed-by: Saeed Mahameed Reviewed-by: Edward Cree Reviewed-by: Alexander Lobakin Link: https://lore.kernel.org/r/20210204213146.4192368-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/core/dev.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) --- a/net/core/dev.c +++ b/net/core/dev.c @@ -5723,10 +5723,11 @@ static void gro_normal_list(struct napi_ /* Queue one GRO_NORMAL SKB up for list processing. If batch size exceeded, * pass the whole batch up to the stack. */ -static void gro_normal_one(struct napi_struct *napi, struct sk_buff *skb) +static void gro_normal_one(struct napi_struct *napi, struct sk_buff *skb, int segs) { list_add_tail(&skb->list, &napi->rx_list); - if (++napi->rx_count >= gro_normal_batch) + napi->rx_count += segs; + if (napi->rx_count >= gro_normal_batch) gro_normal_list(napi); } @@ -5765,7 +5766,7 @@ static int napi_gro_complete(struct napi } out: - gro_normal_one(napi, skb); + gro_normal_one(napi, skb, NAPI_GRO_CB(skb)->count); return NET_RX_SUCCESS; } @@ -6055,7 +6056,7 @@ static gro_result_t napi_skb_finish(stru { switch (ret) { case GRO_NORMAL: - gro_normal_one(napi, skb); + gro_normal_one(napi, skb, 1); break; case GRO_DROP: @@ -6143,7 +6144,7 @@ static gro_result_t napi_frags_finish(st __skb_push(skb, ETH_HLEN); skb->protocol = eth_type_trans(skb, skb->dev); if (ret == GRO_NORMAL) - gro_normal_one(napi, skb); + gro_normal_one(napi, skb, 1); break; case GRO_DROP: