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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,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 932EEC3A5A3 for ; Tue, 27 Aug 2019 16:55:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 738B121881 for ; Tue, 27 Aug 2019 16:55:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730522AbfH0QzZ (ORCPT ); Tue, 27 Aug 2019 12:55:25 -0400 Received: from mail-wr1-f68.google.com ([209.85.221.68]:43661 "EHLO mail-wr1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727138AbfH0QzY (ORCPT ); Tue, 27 Aug 2019 12:55:24 -0400 Received: by mail-wr1-f68.google.com with SMTP id y8so19516778wrn.10 for ; Tue, 27 Aug 2019 09:55:23 -0700 (PDT) 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=nJ6Yhnmx0Z0m7upWdz8dDf2ghGkiqwiluwv7s0RuRzw=; b=r/1/FW9K/xvuA1EMuhXiOewETkY57LpLS0iNzP2MBWFvZaZGgakmL3A0ibspVZjUfj lCqhLhprFwz9oPl5SQrIH5jTABPpvu08gW32+JOnjOfN+yWz0Sr02qjSjrgMfDjsl2Kt YXLCqSjTmy1E9gwIyqStd+/NdVIbnWtBBZ2F6z2HLhvEhV+KFy3DL9cdbhyMSQiZvqww CGd2A03GLxXqEWnzeHhkaCeyIT6TLTX35LUy129/cmnoYJe6YSCzKsBw66gt/KAdwBf+ kNBQySxpywFBr9HY6o4uaEal2gXF+Oq252cmS5PiFt9w0YtDYoweQm3guGFTiI8sUlLE yZUQ== X-Gm-Message-State: APjAAAXwM8MmhYSdK5QcLHq8I5MZVPONwRXTLhY96biUv2GQ+nbDUw7K T50lvqg3/S/mmNro+IJQhTA= X-Google-Smtp-Source: APXvYqzmGy6ajJC6nrDUd+QNoqJqocuS2o207FH1VdgkNulgd++bQf8a5fXl9c/wEjWvyq21q9XK7A== X-Received: by 2002:a05:6000:1186:: with SMTP id g6mr31711139wrx.17.1566924922812; Tue, 27 Aug 2019 09:55:22 -0700 (PDT) Received: from green.intra.ispras.ru (bran.ispras.ru. [83.149.199.196]) by smtp.googlemail.com with ESMTPSA id n14sm54925295wra.75.2019.08.27.09.55.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 27 Aug 2019 09:55:22 -0700 (PDT) From: Denis Efremov To: Andy Whitcroft , Joe Perches Cc: Denis Efremov , linux-kernel@vger.kernel.org Subject: [PATCH] checkpatch: check for nested (un)?likely calls Date: Tue, 27 Aug 2019 19:55:15 +0300 Message-Id: <20190827165515.21668-1-efremov@linux.com> X-Mailer: git-send-email 2.21.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org IS_ERR, IS_ERR_OR_NULL, IS_ERR_VALUE already contain unlikely optimization internally. Thus, there is no point in calling these functions under likely/unlikely. This check is based on the coccinelle rule developed by Enrico Weigelt https://lore.kernel.org/lkml/1559767582-11081-1-git-send-email-info@metux.net/ Signed-off-by: Denis Efremov --- scripts/checkpatch.pl | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 93a7edfe0f05..81dace5ceea5 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -6480,6 +6480,13 @@ sub process { "Using $1 should generally have parentheses around the comparison\n" . $herecurr); } +# nested likely/unlikely calls + if ($perl_version_ok && + $line =~ /\b(?:(?:un)?likely)\s*\(!?\s*(IS_ERR(?:_OR_NULL|_VALUE)?)\s*${balanced_parens}\s*\)/) { + WARN("LIKELY_MISUSE", + "nested (un)?likely calls, unlikely already used in $1 internally\n" . $herecurr); + } + # whine mightly about in_atomic if ($line =~ /\bin_atomic\s*\(/) { if ($realfile =~ m@^drivers/@) { -- 2.21.0