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    <20080815122510.GF20442@elte.hu>
Date: Fri, 15 Aug 2008 09:58:54 -0600 (MDT)
Subject: Re: [PATCH 2.6.27-rc3 26/29] mdb: export task_curr
From: jmerkey@wolfmountaingroup.com
To: "Ingo Molnar" <mingo@elte.hu>
Cc: jmerkey@wolfmountaingroup.com, "Pekka Enberg" <penberg@cs.helsinki.fi>,
       linux-kernel@vger.kernel.org, jason.wessel@windriver.com
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>
> * jmerkey@wolfmountaingroup.com <jmerkey@wolfmountaingroup.com> wrote:
>
>> > On Thu, Aug 14, 2008 at 9:14 AM,  <jmerkey@wolfmountaingroup.com>
>> wrote:
>> >> export the task_curr function to the module based kernel debugger to
>> >> enable
>> >> process back tracing and state display.
>> >>
>> >> Signed-off-by: Jeffrey Vernon Merkey (jmerkey@wolfmountaingroup.com)
>> >>
>> >> --- a/kernel/sched.c    2008-08-13 14:22:32.000000000 -0600
>> >> +++ b/kernel/sched.c    2008-08-13 11:56:03.000000000 -0600
>> >> @@ -1736,6 +1736,9 @@
>> >>  {
>> >>        return cpu_curr(task_cpu(p)) == p;
>> >>  }
>> >> +#if defined(CONFIG_MDB_MODULE)
>> >> +EXPORT_SYMBOL_GPL(task_curr);
>> >> +#endif
>> >
>> > We usually don't export symbols conditionally, especially in core
>> kernel
>> > code.
>> >
>>
>> Well,then please suggest how a kernel debugger can be module based and
>> still be able to get this information some other way that's generic
>> and minimal impact.
>
> FYI, there's a built-in kernel debugger in the upstream kernel already:
> kernel/kgdb.c - and it does not need that export.
>
> So if you are interested in kernel debuggers i'd suggest to work with
> the KGDB folks to extend it with whatever feature-set is missing.
>
> They are friendly, very easy to work with and are open to the
> thousands-of-years-old scientific method of not duplicating effort,
> working together, going forward gradually, etc.
>
> 	Ingo
>

Sorry, but I have my own path and direction, and its not as a tin can on a
strong tied to the tail of kdb or kgdb.    Again, it matters not what's in
Linus' tree or not, but whether this is useful to others and they use it. 
>From what I have seen based on the non-stop downloads from my FTP server,
its needed for certain classes of users -- me included.  I will continue
to enhance it, release it, and move it forward.

kdb and kgdb can go their way.  I'm certain my code is being reviewed as
we speak and if its useful to them, so much the better.

Jeff


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