From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Galbraith <efault@gmx.de>
Subject: Re: [ANNOUNCE] 3.0.1-rt11
Date: Sun, 14 Aug 2011 06:23:41 +0200
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Cc: Peter Zijlstra <peterz@infradead.org>,
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On Sat, 2011-08-13 at 09:27 -0700, Paul E. McKenney wrote:

> Strange.  By the time it got around to printing the stall, no one was
> stalling:
> 
> [  100.409012] INFO: rcu_preempt_state detected stalls on CPUs/tasks: {} (detected by 21, t=60002 jiffies)
> 
> Now it -is- possible for the stall to end just as we get ready to detect
> it, but that window is really really small.  The most recent occurrence
> of this sort of thing was due misconfigured timekeeping, but I don't see
> any sign of that in the trace.
> 
> This happens repeatedly?

Yeah.  When I put -rt9 on the UV box, it was doing the just idling, and
boom thing I saw with earlier releases on both my Q6600 and x3550 M3
boxes.  -rt10 seems to have just changed the timing.

I'll update the x3550 M3, and see if it still gripes.  UV isn't virgin
source, has to be twiddled a little. (symptom was identical though)

	-Mike