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Subject: Re: Floating point in the kernel
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Sean MacLennan <smaclennan@pikatech.com>
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On Thu, 2009-12-10 at 15:33 -0500, Sean MacLennan wrote:
> To be honest, I can't find *why* we are scheduling :( They only way we
> give up the CPU is with locking... and none of the locks where hit
> during the problem. We also never get near our timeslice... the
> longest
> run I saw when the problem happened was 670us. 
> 
> Is there a way to disable scheduling? We currently do not have preempt
> enabled... but may in the future.

Well, that would be interesting to see where you schedule indeed.

Outside of preempt and an explicit lock or memory allocation I don't
see ... Or get/put_user ?

Cheers,
Ben.