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=-9.3 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 CE2E1C433FF for ; Mon, 5 Aug 2019 12:22:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A467220B1F for ; Mon, 5 Aug 2019 12:22:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="rMyVun8j" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728694AbfHEMWd (ORCPT ); Mon, 5 Aug 2019 08:22:33 -0400 Received: from mail-pf1-f196.google.com ([209.85.210.196]:45315 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727259AbfHEMWd (ORCPT ); Mon, 5 Aug 2019 08:22:33 -0400 Received: by mail-pf1-f196.google.com with SMTP id r1so39554155pfq.12 for ; Mon, 05 Aug 2019 05:22:32 -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=D3yEsJczZk4ZuqdPDx5JLOGIqCT05A22pIoztZy5LD4=; b=rMyVun8jDU5nU4z8IENdJOaneaQw2J+d+Rg4cXCoDHJIjW1njTpAtZXF5GaEFM7YjW AIdf1IzEpBtCP6i2ZyH6JWV+KUbSr4xUv9P8ThS3WkjI2D07VeCBjG7glClOCfW7rlLJ 4OGXgRd1fujoEHSLpOiXO/5IeIliDP4rCRWl8ikeaXrbKJETMzDdkwtbQVCFKxV01p1b wiu4xyCJyNK5sNHw+znCtjvNd68vVsdHS8iyOHr5YX0hSN1h3p5sqlA/iOaOBgideP8e ZkIzQ1JMkd6UV7W1H8JYhjhE52BADcEbWxMFjHr/H5jTm+L1cmsqe27IIB/wJm0oPzfc gTmw== 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=D3yEsJczZk4ZuqdPDx5JLOGIqCT05A22pIoztZy5LD4=; b=fYXbkH0i7P0fInZputcNdGFwlKb9Jl1/xNZASYafX0B/8WJf1/xS9qA48v1VA+1n/F FsWHZHiUCCLSPz1QHlQjKTowHWEidYkVcMI1i70ob5jamOQ4/2xiyVYGxPagDURKPum8 Afj2UIhnh6wvYLm/Vsmu0a1an30sbkgri70kbJD96L/UxamXEc19lkTXTb4cl3HLynea Af2XctH7QswMxYmJjKfcQBClP4D4gtCokqxH5VKXwqFHc2II8GzKcZpfyztA50ydSNRK KUfMgY9dfJgvnTIl9rYublhLrCdOawavJz4VODheYAEGPtpBFNXYRBRkihPNQAMWALqG 8whw== X-Gm-Message-State: APjAAAWNWSXMzZc6vpaEvCEKtTKOMT0JmSVO330jdmIV5RpPPFLPUyqs kPwvbFJv3NilYzal0y3/5hs= X-Google-Smtp-Source: APXvYqwogI/fnXLqwAApMoBx9T/YLbLHBkEj2sYreLJgL7EsGb4NcAT0guXujrbqomzYJYPxPETjNQ== X-Received: by 2002:a63:cc14:: with SMTP id x20mr90544477pgf.142.1565007752637; Mon, 05 Aug 2019 05:22:32 -0700 (PDT) Received: from suzukaze.ipads-lab.se.sjtu.edu.cn ([89.31.126.54]) by smtp.gmail.com with ESMTPSA id a12sm12472578pgv.48.2019.08.05.05.22.26 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Mon, 05 Aug 2019 05:22:32 -0700 (PDT) From: Chuhong Yuan Cc: Christoph Hellwig , Marek Szyprowski , Robin Murphy , iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Chuhong Yuan Subject: [PATCH v3 1/8] dma: debug: Replace strncmp with str_has_prefix Date: Mon, 5 Aug 2019 20:22:20 +0800 Message-Id: <20190805122220.12878-1-hslester96@gmail.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit To: unlisted-recipients:; (no To-header on input) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org strncmp(str, const, len) is error-prone because len is easy to have typo. The example is the hard-coded len has counting error or sizeof(const) forgets - 1. So we prefer using newly introduced str_has_prefix() to substitute such strncmp to make code better. Signed-off-by: Chuhong Yuan --- Changes in v3: - Revise the description. kernel/dma/debug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c index 099002d84f46..0f9e1aba3e1a 100644 --- a/kernel/dma/debug.c +++ b/kernel/dma/debug.c @@ -970,7 +970,7 @@ static __init int dma_debug_cmdline(char *str) if (!str) return -EINVAL; - if (strncmp(str, "off", 3) == 0) { + if (str_has_prefix(str, "off")) { pr_info("debugging disabled on kernel command line\n"); global_disable = true; } -- 2.20.1