From mboxrd@z Thu Jan  1 00:00:00 1970
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Subject: Re: Decermenter overflow interrupt atfer the init.d launch.
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Kumar Gala <galak@kernel.crashing.org>
In-Reply-To: <D4037DB6-8832-4057-A9FF-BAD32592E6C9@kernel.crashing.org>
References: <46A9925A.2060508@yahoo.fr>
	<D4037DB6-8832-4057-A9FF-BAD32592E6C9@kernel.crashing.org>
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Date: Fri, 27 Jul 2007 17:26:20 +1000
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On Fri, 2007-07-27 at 01:46 -0500, Kumar Gala wrote:
> On Jul 27, 2007, at 1:36 AM, Nicolas Mederle wrote:
> 
> > Hi,
> >
> >        I want to know how the kernel switch the task. Because my  
> > kernel
> > start very well, and it launch  the init.d. With the log, i can see  
> > that
> > the kernel launch the getty task. But after, there is a decrementer
> > overflow interrupt  ( vector at adress 900 ). Is it the task  
> > switch? Or
> > is it an error in the decrementer init.
> 
> This should be a task switch.  The decrementer is used to handle the  
> periodic interrupt to switch processes.

I would have expected quite of few of these actually before you get
there :-)

Ben.