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int r; - r = snprintf(buf, sizeof(buf), "%ld\n", *ptr); - if (r > sizeof(buf)) - r = sizeof(buf); + r = scnprintf(buf, sizeof(buf), "%ld\n", *ptr); return simple_read_from_buffer(ubuf, count, ppos, buf, r); } -- 2.7.4 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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,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 92C41C282DD for ; Fri, 10 Jan 2020 00:57:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5BDBA2073A for ; Fri, 10 Jan 2020 00:57:11 +0000 (UTC) Authentication-Results: mail.kernel.org; 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Thu, 09 Jan 2020 16:57:09 -0800 (PST) From: liuyang34 X-Google-Original-From: liuyang34 To: Steven Rostedt , Ingo Molnar , linux-kernel@vger.kernel.org Cc: liuyang34 Subject: [RESEND PATCH] trace: code optimization Date: Fri, 10 Jan 2020 08:57:04 +0800 Message-Id: <27225bf0ec9b4e2f3d313456aee75e294361d550.1578561009.git.liuyang34@xiaomi.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Message-ID: <20200110005704.uBMnxTvuVyW2xGC38tgnSxFophSupLbsUGYG1nSPEQk@z> use scnprintf instead of snprintf and no need to check the return size again Signed-off-by: liuyang --- kernel/trace/trace_stack.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c index c557f42..7b15e9a 100644 --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -329,9 +329,7 @@ stack_max_size_read(struct file *filp, char __user *ubuf, char buf[64]; int r; - r = snprintf(buf, sizeof(buf), "%ld\n", *ptr); - if (r > sizeof(buf)) - r = sizeof(buf); + r = scnprintf(buf, sizeof(buf), "%ld\n", *ptr); return simple_read_from_buffer(ubuf, count, ppos, buf, r); } -- 2.7.4