From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Molnar <mingo@elte.hu>
Subject: Re: [PATCH]sched: fix typo in sched-rt-group.txt file
Date: Tue, 12 May 2009 11:42:10 +0200
Message-ID: <20090512094210.GD32292@elte.hu>
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To: Peter Zijlstra <a.p.zijlstra@chello.nl>
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* Peter Zijlstra <a.p.zijlstra@chello.nl> wrote:

> On Tue, 2009-05-12 at 17:37 +0900, GeunSik Lim wrote:
> > 
> > 
> > Dear Ingo,
> > 
> > I found typo about the range of static priority ( = realtime priority )
> > in "./Documentation/scheduler/sched-rt-group.txt" file.
> > 
> > If I don't understand static priority levels, Correct me.
> 
> Right, that 'confusion' stems from the fact that our in-kernel priority
> lists do consider all 140 priorities.
> 
> The patch looks good though.
> 
> > commit d6af702008117ca489a2f5476239d1688a517e98
> > Author: GeunSik,Lim <leemgs1@gmail.com>
> > Date:   Tue May 12 17:20:32 2009 +0900
> > 
> >     sched: fix typo in sched-rt-group.txt file
> >     
> >     Fix typo about static priority's range.
> >      Kernel Space priority: 0   to 99   --> User Space RT priority 99 to 0
> >      Kernel Space priority: 100 to 139  --> User Space nice -20 to 19
> >     
> >     Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com>
> > 
> > diff --git a/Documentation/scheduler/sched-rt-group.txt b/Documentation/scheduler/sched-rt-group.txt
> > index 5ba4d3f..1537146 100644
> > --- a/Documentation/scheduler/sched-rt-group.txt
> > +++ b/Documentation/scheduler/sched-rt-group.txt
> > @@ -169,7 +169,7 @@ get their allocated time.
> >  
> >  Implementing SCHED_EDF might take a while to complete. Priority Inheritance is
> >  the biggest challenge as the current linux PI infrastructure is geared towards
> > -the limited static priority levels 0-139. With deadline scheduling you need to
> > +the limited static priority levels 0-99. With deadline scheduling you need to

SCHED_FIFO goes from 1 to 99. So it's either 0-98 or 1-99. From 
sched_setscheduler(2):

       Processes scheduled under one of  the  real-time  policies  (SCHED_FIFO,
       SCHED_RR) have a sched_priority value in the range 1 (low) to 99 (high).

	Ingo