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Subject: Re: It hurts when I shoot myself in the foot
From: Austin Gonyou <austin@digitalroadkill.net>
To: Kasper Dupont <kasperd@daimi.au.dk>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>,
        Linux-Kernel <linux-kernel@vger.kernel.org>
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On Fri, 2002-05-24 at 10:36, Kasper Dupont wrote:
> Alan Cox wrote:
> > 
> > > If the kernel knew multipliers couldn't it actually use the TSCs
> > > anyway? Of course it would take some work, but is there any
> > > reason why it would not be posible?
> > 
> > In 2.4 yes. In 2.5 it would be close to impossible due to the pre-empt code
> 
> Couldn't that be solved in one of the following ways?
> 
> 1) Disable pre-emption while reading TSC and CPU nr.
> 2) Use affinity for processes pre-empted in kernel mode.
> 3) Disable pre-emption for SMP systems.
> 
Sorry to chime in on this if it isn't appreciated, but wouldn't #3 open
some old wounds again? It seems that it would FMPOV. 

Austin