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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 81C0AC47258 for ; Fri, 1 May 2020 14:01:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5816C2051A for ; Fri, 1 May 2020 14:01:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588341710; bh=FIl5LxAo3sAnFk0EG7vW2iQiLwXy00fRa5v3cZeQbw0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=MNi6UN2rZ4c6pZacbInovj8DXCHWrX4ZsSlq8miUwubpl7xVssSi6pJWo97LErlyj 8v51ISm22hIoLim6gofPyBGQuZ6y9zAtQ+/MgPZPpVXsBt+q3IukYTfrXMquZywIwl WfUC6gBNaVJnayNgLtNXH9r2e97gs3Yk3Y7Xag9U= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728854AbgEAOBt (ORCPT ); Fri, 1 May 2020 10:01:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:46204 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728993AbgEANZU (ORCPT ); Fri, 1 May 2020 09:25:20 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2D0542495E; Fri, 1 May 2020 13:25:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588339519; bh=FIl5LxAo3sAnFk0EG7vW2iQiLwXy00fRa5v3cZeQbw0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=h9HCxwMM7KTfm6JDv1eiyc0pKGBSAQ3ljJ2/JgRX9P19zJKBcowVlWdfskJNWEt9P 5zygeIKArbCRLDqbPqoza/VQidKPNQCsI26HMo9XNuJQnQc7rICmVYHIzIDmvqEKTQ yPXZvxFi+fwe/N5ton//6e5C7tul3wI+YcPGovyc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , Soheil Hassas Yeganeh , "David S. Miller" Subject: [PATCH 4.4 22/70] tcp: cache line align MAX_TCP_HEADER Date: Fri, 1 May 2020 15:21:10 +0200 Message-Id: <20200501131521.123720775@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200501131513.302599262@linuxfoundation.org> References: <20200501131513.302599262@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eric Dumazet [ Upstream commit 9bacd256f1354883d3c1402655153367982bba49 ] TCP stack is dumb in how it cooks its output packets. Depending on MAX_HEADER value, we might chose a bad ending point for the headers. If we align the end of TCP headers to cache line boundary, we make sure to always use the smallest number of cache lines, which always help. Signed-off-by: Eric Dumazet Cc: Soheil Hassas Yeganeh Acked-by: Soheil Hassas Yeganeh Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/net/tcp.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -52,7 +52,7 @@ extern struct inet_hashinfo tcp_hashinfo extern struct percpu_counter tcp_orphan_count; void tcp_time_wait(struct sock *sk, int state, int timeo); -#define MAX_TCP_HEADER (128 + MAX_HEADER) +#define MAX_TCP_HEADER L1_CACHE_ALIGN(128 + MAX_HEADER) #define MAX_TCP_OPTION_SPACE 40 #define TCP_MIN_SND_MSS 48 #define TCP_MIN_GSO_SIZE (TCP_MIN_SND_MSS - MAX_TCP_OPTION_SPACE)