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Date:   Wed, 7 Sep 2022 16:54:00 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Jim Cromie <jim.cromie@gmail.com>
Cc:     jbaron@akamai.com, dri-devel@lists.freedesktop.org,
        amd-gfx@lists.freedesktop.org, intel-gvt-dev@lists.freedesktop.org,
        intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        daniel.vetter@ffwll.ch, seanpaul@chromium.org, robdclark@gmail.com,
        linux@rasmusvillemoes.dk, joe@perches.com
Subject: Re: [PATCH v6 21/57] dyndbg: test DECLARE_DYNDBG_CLASSMAP, sysfs
 nodes
Message-ID: <YxiwiO+Ni/CvAO5Q@kroah.com>
References: <20220904214134.408619-1-jim.cromie@gmail.com>
 <20220904214134.408619-22-jim.cromie@gmail.com>
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On Sun, Sep 04, 2022 at 03:40:58PM -0600, Jim Cromie wrote:
> Demonstrate use of DECLARE_DYNDBG_CLASSMAP macro, and expose them as
> sysfs-nodes for testing.

Wait, why sysfs?

sysfs isn't for testing, why not use debugfs?


> 
> For each of the 4 class-map-types:
> 
>   - declare a class-map of that type,
>   - declare the enum corresponding to those class-names
>   - share _base across 0..30 range
>   - add a __pr_debug_cls() call for each class-name
>   - declare 2 sysnodes for each class-map
>     for 'p' flag, and future 'T' flag
> 
> These declarations create the following sysfs parameter interface:
> 
>   :#> pwd
>   /sys/module/test_dynamic_debug/parameters
>   :#> ls
>   T_disjoint_bits  T_disjoint_names  T_level_names  T_level_num  do_prints
>   p_disjoint_bits  p_disjoint_names  p_level_names  p_level_num

What is in these files?

For sysfs stuff, you need Documentation/ABI entries so that you can't
abuse sysfs.  With debugfs, you can do anything you want :)

thanks,

greg k-h