From patchwork Thu Jul 22 18:50:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kangmin Park X-Patchwork-Id: 484288 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=-15.8 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, 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 7B399C4338F for ; Thu, 22 Jul 2021 18:50:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5E89160EB9 for ; Thu, 22 Jul 2021 18:50:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230153AbhGVSKA (ORCPT ); Thu, 22 Jul 2021 14:10:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50570 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229771AbhGVSJ7 (ORCPT ); Thu, 22 Jul 2021 14:09:59 -0400 Received: from mail-pl1-x62a.google.com (mail-pl1-x62a.google.com [IPv6:2607:f8b0:4864:20::62a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4DB0BC061757; Thu, 22 Jul 2021 11:50:34 -0700 (PDT) Received: by mail-pl1-x62a.google.com with SMTP id n10so283264plf.4; Thu, 22 Jul 2021 11:50:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=wlySsb7NCcOdNyg1NZSKXQbRNOuXci6cKFNHTYDMHGI=; b=tANL0sX86ZD+GqZzcCkAad8AnyAZk6TTJGaGkR/4dyZtkl623k8o1TY+N8OwmijmtX 7TrPOQV58VIi+OvKiMUQD0F0Aj8fgFvcGvEIj+E5pnOrJih29RGeTW0cB1m0a/F/vWcN sqOB2rX+b3qJmMb0v0ASLQ125Ib/E+iaGMHOwA4KYJX8SbfSO8NwJ6l6uoBJo83ua63Y ykMfg0+dUCQbtMpwvmLSYo+Eo643YOCl3OEtSywPPw/AbU9yT0FU72AQQS9bp+EFHbFM lF1ImXC/bOSl6DZ78nujZ8Qn8eTroilrSccRoeMFyaV0Yhd/JnM0r1PlERoaJLBD6x6O JYBw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=wlySsb7NCcOdNyg1NZSKXQbRNOuXci6cKFNHTYDMHGI=; b=E+puHFRKEnvo67VlpE0oEz0ujrLT7R0gpdM/u4Gcr50gmAHrfR/NlE1GYz6isZolkf +YWj2QcnUJ8nfDVPV7hTU05utss1I4u6aEfnunucZVdGEqzyljXQ0kFTVEhxxVKddt7q vcsGqa6tQeb8yG52+wGVE7ZIbbVpPVDTNyh7rG37MlZLpe1Dl+XLzYpcMBdDmd1BOllX Bs4Z9KjJd9ihtM2FnHGUb3l9nO7Im7pYab6OhGNYAJiLKKpKoq3foBvCJIBX7J6F4GJr xH8n6RD/vbhoKwcFiDdVzZmHhKThJzP+KuaDLgV01rm97wneC4txr6ME393Mg5Nqs7eo 9oqA== X-Gm-Message-State: AOAM530rGexhvLPXN6sD8iqlIhLLjzbM6bgfxEZ2oYF5uwYovDbN7IgS QLzLp/+rB8RZzW3n0l6nDro= X-Google-Smtp-Source: ABdhPJz+a6SU4QCvQpOJI9b8Z9IKDFCARTxqrN1f68A2kc5XvltUnF3KwjiRNwC0K9z+Ic8FvyizNA== X-Received: by 2002:a17:90b:1e50:: with SMTP id pi16mr1042402pjb.147.1626979833836; Thu, 22 Jul 2021 11:50:33 -0700 (PDT) Received: from localhost.localdomain ([1.240.193.107]) by smtp.googlemail.com with ESMTPSA id w2sm5394925pjf.2.2021.07.22.11.50.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 22 Jul 2021 11:50:33 -0700 (PDT) From: Kangmin Park To: "David S. Miller" Cc: Jakub Kicinski , Martin Varghese , Jiapeng Chong , "Gustavo A. R. Silva" , Guillaume Nault , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] mpls: defer ttl decrement in mpls_forward() Date: Fri, 23 Jul 2021 03:50:28 +0900 Message-Id: <20210722185028.17555-1-l4stpr0gr4m@gmail.com> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Defer ttl decrement to optimize in tx_err case. There is no need to decrease ttl in the case of goto tx_err. Signed-off-by: Kangmin Park --- net/mpls/af_mpls.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c index 05a21dd072df..ffeb2df8be7a 100644 --- a/net/mpls/af_mpls.c +++ b/net/mpls/af_mpls.c @@ -407,7 +407,6 @@ static int mpls_forward(struct sk_buff *skb, struct net_device *dev, /* Verify ttl is valid */ if (dec.ttl <= 1) goto err; - dec.ttl -= 1; /* Find the output device */ out_dev = rcu_dereference(nh->nh_dev); @@ -431,6 +430,7 @@ static int mpls_forward(struct sk_buff *skb, struct net_device *dev, skb->dev = out_dev; skb->protocol = htons(ETH_P_MPLS_UC); + dec.ttl -= 1; if (unlikely(!new_header_size && dec.bos)) { /* Penultimate hop popping */ if (!mpls_egress(dev_net(out_dev), rt, skb, dec))