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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 5B52DC04EB9 for ; Thu, 6 Dec 2018 09:21:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 21DFB21479 for ; Thu, 6 Dec 2018 09:21:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 21DFB21479 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=daenzer.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729244AbeLFJVs (ORCPT ); Thu, 6 Dec 2018 04:21:48 -0500 Received: from mail.netline.ch ([148.251.143.178]:55361 "EHLO netline-mail3.netline.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727763AbeLFJVs (ORCPT ); Thu, 6 Dec 2018 04:21:48 -0500 Received: from localhost (localhost [127.0.0.1]) by netline-mail3.netline.ch (Postfix) with ESMTP id BE6C82A604C; Thu, 6 Dec 2018 10:21:45 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at netline-mail3.netline.ch Received: from netline-mail3.netline.ch ([127.0.0.1]) by localhost (netline-mail3.netline.ch [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 744l9qAB3yMI; Thu, 6 Dec 2018 10:21:41 +0100 (CET) Received: from thor (39.1.199.178.dynamic.wline.res.cust.swisscom.ch [178.199.1.39]) by netline-mail3.netline.ch (Postfix) with ESMTPSA id 172982A604B; Thu, 6 Dec 2018 10:21:41 +0100 (CET) Received: from localhost ([::1]) by thor with esmtp (Exim 4.91) (envelope-from ) id 1gUpqm-0003db-P2; Thu, 06 Dec 2018 10:21:40 +0100 Subject: Re: [PATCH 1/2] drm: Only #define DEBUG if CONFIG_DYNAMIC_DEBUG is disabled To: Chris Wilson , "Zhang, Jerry(Junwei)" , Christian Koenig , David Airlie , Huang Rui , Maarten Lankhorst , Maxime Ripard , Sean Paul Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org References: <20181205165621.5805-1-michel@daenzer.net> <10fca21a-5d7c-fe9e-07f0-6200e9de538e@amd.com> <154408757908.3572.9138595858555797029@skylake-alporthouse-com> From: =?UTF-8?Q?Michel_D=c3=a4nzer?= Openpgp: preference=signencrypt Autocrypt: addr=michel@daenzer.net; prefer-encrypt=mutual; keydata= mQGiBDsehS8RBACbsIQEX31aYSIuEKxEnEX82ezMR8z3LG8ktv1KjyNErUX9Pt7AUC7W3W0b LUhu8Le8S2va6hi7GfSAifl0ih3k6Bv1Itzgnd+7ZmSrvCN8yGJaHNQfAevAuEboIb+MaVHo 9EMJj4ikOcRZCmQWw7evu/D9uQdtkCnRY9iJiAGxbwCguBHtpoGMxDOINCr5UU6qt+m4O+UD /355ohBBzzyh49lTj0kTFKr0Ozd20G2FbcqHgfFL1dc1MPyigej2gLga2osu2QY0ObvAGkOu WBi3LTY8Zs8uqFGDC4ZAwMPoFy3yzu3ne6T7d/68rJil0QcdQjzzHi6ekqHuhst4a+/+D23h Za8MJBEcdOhRhsaDVGAJSFEQB1qLBACOs0xN+XblejO35gsDSVVk8s+FUUw3TSWJBfZa3Imp V2U2tBO4qck+wqbHNfdnU/crrsHahjzBjvk8Up7VoY8oT+z03sal2vXEonS279xN2B92Tttr AgwosujguFO/7tvzymWC76rDEwue8TsADE11ErjwaBTs8ZXfnN/uAANgPLQjTWljaGVsIERh ZW56ZXIgPG1pY2hlbEBkYWVuemVyLm5ldD6IXgQTEQIAHgUCQFXxJgIbAwYLCQgHAwIDFQID AxYCAQIeAQIXgAAKCRBaga+OatuyAIrPAJ9ykonXI3oQcX83N2qzCEStLNW47gCeLWm/QiPY jqtGUnnSbyuTQfIySkK5AQ0EOx6FRRAEAJZkcvklPwJCgNiw37p0GShKmFGGqf/a3xZZEpjI qNxzshFRFneZze4f5LhzbX1/vIm5+ZXsEWympJfZzyCmYPw86QcFxyZflkAxHx9LeD+89Elx bw6wT0CcLvSv8ROfU1m8YhGbV6g2zWyLD0/naQGVb8e4FhVKGNY2EEbHgFBrAAMGA/0VktFO CxFBdzLQ17RCTwCJ3xpyP4qsLJH0yCoA26rH2zE2RzByhrTFTYZzbFEid3ddGiHOBEL+bO+2 GNtfiYKmbTkj1tMZJ8L6huKONaVrASFzLvZa2dlc2zja9ZSksKmge5BOTKWgbyepEc5qxSju YsYrX5xfLgTZC5abhhztpYhGBBgRAgAGBQI7HoVFAAoJEFqBr45q27IAlscAn2Ufk2d6/3p4 Cuyz/NX7KpL2dQ8WAJ9UD5JEakhfofed8PSqOM7jOO3LCA== Message-ID: Date: Thu, 6 Dec 2018 10:21:40 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.3.1 MIME-Version: 1.0 In-Reply-To: <154408757908.3572.9138595858555797029@skylake-alporthouse-com> Content-Type: text/plain; charset=utf-8 Content-Language: en-CA Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2018-12-06 10:12 a.m., Chris Wilson wrote: > Quoting Zhang, Jerry(Junwei) (2018-12-06 02:40:42) >> On 12/6/18 12:56 AM, Michel Dänzer wrote: >>> From: Michel Dänzer >>> >>> The following cases are possible for pr_debug(): >>> >>> 1. CONFIG_DYNAMIC_DEBUG disabled >>> a) DEBUG not defined: pr_debug() translates to no_printk(...), i.e. >>> it never generates any output. >>> b) DEBUG defined: pr_debug() translates to printk(KERN_DEBUG ...), >>> i.e. it generates output which doesn't appear in dmesg by default, >>> can be enabled dynamically. >>> >>> 2. CONFIG_DYNAMIC_DEBUG enabled: pr_debug() translates to >>> dynamic_pr_debug() >>> a) DEBUG not defined: dynamic_pr_debug() generates no output by >>> default, can be enabled dynamically. >>> b) DEBUG defined: dynamic_pr_debug() generates output by default, >>> can be disabled dynamically. >>> >>> The intention for drm_debug_printer() is to generate output which >>> doesn't appear in dmesg by default, but can be enabled dynamically, i.e. >>> cases 1b) and 2a). However, defining DEBUG unconditionally gave us 2b) >>> instead of 2a) with CONFIG_DYNAMIC_DEBUG enabled. >>> >>> Fixes: 79a5ad2fdb3c ("drm: Enable pr_debug() for drm_printer") >>> Signed-off-by: Michel Dänzer >> Reviewed-by: Junwei Zhang > > At the cost of 1a? Nah. We still #define DEBUG if CONFIG_DYNAMIC_DEBUG isn't defined, so it's still 1b), not 1a). -- Earthling Michel Dänzer | http://www.amd.com Libre software enthusiast | Mesa and X developer