From patchwork Thu Feb 22 18:29:02 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Philip Cox X-Patchwork-Id: 1902917 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ubuntu.com (client-ip=185.125.189.65; helo=lists.ubuntu.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=patchwork.ozlabs.org) Received: from lists.ubuntu.com (lists.ubuntu.com [185.125.189.65]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4TghYW3cKGz23f7 for ; Fri, 23 Feb 2024 05:31:26 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=lists.ubuntu.com) by lists.ubuntu.com with esmtp (Exim 4.86_2) (envelope-from ) id 1rdDqk-0007MP-Ox; Thu, 22 Feb 2024 18:31:14 +0000 Received: from smtp-relay-internal-1.internal ([10.131.114.114] helo=smtp-relay-internal-1.canonical.com) by lists.ubuntu.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1rdDqh-0007Ke-Fb for kernel-team@lists.ubuntu.com; Thu, 22 Feb 2024 18:31:11 +0000 Received: from mail-qk1-f199.google.com (mail-qk1-f199.google.com [209.85.222.199]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp-relay-internal-1.canonical.com (Postfix) with ESMTPS id 2EC7A3F636 for ; Thu, 22 Feb 2024 18:31:11 +0000 (UTC) Received: by mail-qk1-f199.google.com with SMTP id af79cd13be357-783350c4584so1227074785a.1 for ; Thu, 22 Feb 2024 10:31:11 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1708626669; x=1709231469; h=content-transfer-encoding:mime-version:message-id:date:subject:to :from:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=DAZ14Nf/iBHbcCLMNJFZMlcTYiP5jKzDQCmcks7Z/Jc=; b=WgBYzQVD4XDSYYXBUEZbCUKkzRQhwnprpyCtao+T1X09WEtjHsf1DVBclaymP/9knr u7p93qQscEqDmn1yvUfhwpPlg5a1lT0ByWHSXc7fMbKF5FWjW4ZCbRTu3fbAeNFagWZn 3tZ6fo38pVGhDu1wIfaNmgTfuvAgZxvmGR30MLh4db6RfNrVEVODEB2ChPjaLsxju4tO HRzP9NR9qCasdeelNhkVPAXjVMof0IM06XidIEfcgycLQrETfIt6+ZdSsWVz4qyHveJ0 oUjNkSWq1vFGWSL9EhgFEAChX9HA7aFiYiVVbXEO0i2CzK10rwDS0WmDzlqc2GA8zxTU zr0w== X-Gm-Message-State: AOJu0YxnFEGTLQ9q/HV06sCxRB3OxcE3Bnt06enHH/O9mKFBzVRHwGLq ql1HsbDRkhvh7Tpi2DaOknCdgybD/jjnoNh/vjlFkNDiWk1CY7W16fy4JkBwrWVmZFG5MNZgLHA ANnbPjx89B276XnokeznlgDcBXS7hAGwUW+KGxqL+6Vwdom3hS5N7ckr62a40Tfvn+hhKfnEobl 42thRSuwAegQ== X-Received: by 2002:a05:620a:1013:b0:783:bfb7:77d5 with SMTP id z19-20020a05620a101300b00783bfb777d5mr24945151qkj.78.1708626668786; Thu, 22 Feb 2024 10:31:08 -0800 (PST) X-Google-Smtp-Source: AGHT+IFjKxSa+0JPOZuOAH6vKQrq8e5ubMCsvAdRfRgRtgEIaubB0cCVJLykqRKayHdRhxmfzOpC2A== X-Received: by 2002:a05:620a:1013:b0:783:bfb7:77d5 with SMTP id z19-20020a05620a101300b00783bfb777d5mr24945135qkj.78.1708626668464; Thu, 22 Feb 2024 10:31:08 -0800 (PST) Received: from cox.home.arpa ([108.175.227.176]) by smtp.gmail.com with ESMTPSA id e26-20020a05620a209a00b00785da717d64sm5545171qka.111.2024.02.22.10.31.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 22 Feb 2024 10:31:07 -0800 (PST) From: Philip Cox To: kernel-team@lists.ubuntu.com, philip.cox@canonical.com Subject: [f/j/m:linux-aws][PATCH 0/1] tcp: Add memory barrier to tcp_push Date: Thu, 22 Feb 2024 13:29:02 -0500 Message-Id: <20240222182903.1490015-1-philip.cox@canonical.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" BugLink: https://bugs.launchpad.net/bugs/2051727 SRU Justification: [Impact] Recently a patch has been accepted on the Linux Kernel regarding the TCP stack which fix an additional +40ms latency on ARM64 CPU architecture without impacting other CPU types. [Fix] Upstream patch: 7267e8dcad6b2f9fce05a6a06335d7040acbc2b6: tcp: Add memory barrier to tcp_push() was submitted to address this. [Test Plan] AWS tested [Where problems could occur] The risk of regressions from this change is fairly low. Acked-by: Tim Gardner Acked-by: Magali Lemes --- Salvatore Dipietro (1): tcp: Add memory barrier to tcp_push() net/ipv4/tcp.c | 1 + 1 file changed, 1 insertion(+)