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;
Message-ID: <733672ada4f532f02137067b14d285728cdd120c.camel@perches.com>
Subject: Re: [PATCH 1/2] drm: Only #define DEBUG if CONFIG_DYNAMIC_DEBUG is
 disabled
From:   Joe Perches <joe@perches.com>
To:     Michel =?ISO-8859-1?Q?D=E4nzer?= <michel@daenzer.net>,
        "Zhang, Jerry(Junwei)" <Jerry.Zhang@amd.com>,
        Christian Koenig <christian.koenig@amd.com>,
        Huang Rui <ray.huang@amd.com>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <maxime.ripard@bootlin.com>,
        Sean Paul <sean@poorly.run>, David Airlie <airlied@linux.ie>,
        Chris Wilson <chris@chris-wilson.co.uk>
Cc:     linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org
Date:   Thu, 06 Dec 2018 08:22:46 -0800
In-Reply-To: <747d6c1b-8c0a-8168-bd1e-e969839ff5be@daenzer.net>
References: <20181205165621.5805-1-michel@daenzer.net>
         <10fca21a-5d7c-fe9e-07f0-6200e9de538e@amd.com>
         <1586a49594d30b4bf4d88eba0d258e21efd26da2.camel@perches.com>
         <276fbf7f-d33f-83a5-cb88-bd4051dc03ba@daenzer.net>
         <e7859ce4b8417b094604d9ab4740d338730e38bf.camel@perches.com>
         <d2a1f009-b2c7-240d-7e1c-e48a08d8ac7d@daenzer.net>
         <61385d4cb6c9d990427349849d0af28faa3b67af.camel@perches.com>
         <747d6c1b-8c0a-8168-bd1e-e969839ff5be@daenzer.net>
Content-Type: text/plain; charset="ISO-8859-1"
User-Agent: Evolution 3.30.1-1build1 
Mime-Version: 1.0
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Thu, 2018-12-06 at 15:41 +0100, Michel D?nzer wrote:
> On 2018-12-06 1:23 p.m., Joe Perches wrote:
> > On Thu, 2018-12-06 at 12:52 +0100, Michel D?nzer wrote:
> > > In contrast to the 2b case, the pr_debug output isn't visible by default
> > > with 1b, so the latter doesn't fit "always produce output" either.
> > 
> > I think you are mistaken here.
> 
> Still puzzled as to what you're hoping to achieve with that kind of
> language. None of the confusion about this patch has been on my part. :)

Doubtful.

> > Adding #define DEBUG as Chris did enables pr_debug output
> > and is your 1b.
> > 
> > Perhaps your default console logging level is set to a
> > non-default value.
> 
> I have CONFIG_DYNAMIC_DEBUG enabled in my kernels. The problem addressed
> by this patch is that messages from drm_debug_printer are visible by
> default (case 2b), whereas they shouldn't be (case 2a, like 1b).

The default for config_dynamic_debug when DEBUG is defined is
to output the message equivalent to when DEBUG is defined and
config_dynamic_debug is not.

That's a good thing and has been the general default since 2011.

You want to override that, I suppose that's OK but it's
definitely not a _fix_ as you have written.

It's just a change in behavior.

You added a "Fixes:" line.  I believe that wrong.

A long time ago, at my suggestion:

commit b558c96ffa53f4b3dd52b774e4fb7a52982ab52b
Author: Jim Cromie <jim.cromie@gmail.com>
Date:   Mon Dec 19 17:11:18 2011 -0500

    dynamic_debug: make dynamic-debug supersede DEBUG ccflag
    
    If CONFIG_DYNAMIC_DEBUG is defined, honor it over DEBUG, so that
    pr_debug()s are controllable, instead of always-on.  When DEBUG is
    also defined, change _DPRINTK_FLAGS_DEFAULT to enable printing by
    default.

cheers, Joe