Received: by 10.223.176.5 with SMTP id f5csp2518269wra; Sun, 28 Jan 2018 22:51:36 -0800 (PST) X-Google-Smtp-Source: AH8x227LjFWRd9NRhD9a2E5CPAuBJto9USUFyrYOBvBptzPEBK61fieWjKcFloKY+D5DRlgNzDBs X-Received: by 2002:a17:902:581a:: with SMTP id m26-v6mr20798953pli.158.1517208696508; Sun, 28 Jan 2018 22:51:36 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1517208696; cv=none; d=google.com; s=arc-20160816; b=q1f+KDL+nyDwOC2F40fl7J8Aoavk0NwybPZPiiUvktkd5HOTfCgWZYfSYD1wZUaf6x GBCb7vyVeRb8KRDpO6ZR2KxWKKNeEA8a9cA3SzECxVSyUeWUlYFzH7xY9A5xPfIP+QBN QP7BZqZuNwjv1XKfgZi7EQ0GQQ/zs+Dtjpmal2rLSmwIcnq317bg4KTs8bFdX7R1MC4C UCWvQjKeWPFPVFeZoK5O0fBzXP4CAuGHzpqU3Uok46ECNYhoW1cHkdIvyeGda3azKkjt YVnQwCKa8fqYXFQMzgoTzWWq9dHROsIFGanWwuE7uVi1vhdTWx/O0P1boJM7NU70qWZX Kr1Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date:arc-authentication-results; bh=0CLfvBO6wjjSn3dBkkSRCRwrtTTwp6GBFYVH+eOQoQ8=; b=d1Wye72RbK8+mVzDK+Y1yr5WfKSuK2RQ0A81uqK2AXBmecI78ZqjHL5G/aAlWjhDga zMFDFq+8yD9KyfiWUAlhnrOX4Hu31AxsMWlMixw0RN3L+BpswMmYx1Gej6JTUbQGxq+N +VnGadhkj/cqw8+jhCaae0SYOz/wLMMSXi1QacrKlipnv7yVhSWYug67PFwSRkE7o0Aq OZK+quuVepEuQvtcnCh54xARhNfGnzbIbyTaxVu9jmhIQ8uYvczzpw0Tp5ZXeAX6O8t7 kEWHzxLmnGmst1PnGUkmTeXm4/fdkkMZq6tqYQNOlxGFlodASUYN48YYgVrJFObjlCJT PTHA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id b129si6891917pgc.89.2018.01.28.22.51.20; Sun, 28 Jan 2018 22:51:36 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751273AbeA2Gu5 (ORCPT + 99 others); Mon, 29 Jan 2018 01:50:57 -0500 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:40193 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751032AbeA2Gu4 (ORCPT ); Mon, 29 Jan 2018 01:50:56 -0500 Received: (from willy@localhost) by pcw.home.local (8.15.2/8.15.2/Submit) id w0T6orB1020353; Mon, 29 Jan 2018 07:50:53 +0100 Date: Mon, 29 Jan 2018 07:50:53 +0100 From: Willy Tarreau To: Jia-Ju Bai Cc: miguel.ojeda.sandonis@gmail.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] auxdisplay: charlcd: delete mdelay in long_sleep Message-ID: <20180129065053.GC20230@1wt.eu> References: <1516979955-7466-1-git-send-email-baijiaju1990@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1516979955-7466-1-git-send-email-baijiaju1990@gmail.com> User-Agent: Mutt/1.6.1 (2016-04-27) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Fri, Jan 26, 2018 at 11:19:15PM +0800, Jia-Ju Bai wrote: > The function long_sleep() calls mdelay() when in an interrupt handler. > But only charlcd_clear_display() and charlcd_init_display calls > long_sleep(), and my tool finds that the two functions > are never called in an interrupt handler. > Thus mdelay() and in_interrupt() are not necessary. > > This is found by a static analysis tool named DCNS written by myself. Looks good. This code is extremely old (started in 2.2) so I'm not surprised at all that after many changes such parts are not used anymore. Acked-by: Willy Tarreau Willy