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Date: Thu, 17 Aug 2000 11:52:39 -0400 (EDT)
From: Thomas Valentino Crimi <tcrimi+@andrew.cmu.edu>
To: hackers@freebsd.org, Karl Pielorz <kpielorz@tdx.co.uk>
Subject: Re: Critical (or equivalent) section in Userland?
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In-Reply-To: <399BA212.A84240AE@tdx.co.uk>
References: <399BA212.A84240AE@tdx.co.uk>
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Excerpts from FreeBSD-Hackers: 17-Aug-100 Critical (or equivalent) se..
by Karl Pielorz@tdx.co.uk 
> The software is running as user 'root' - does anyone have any pointers on how
> I can do this? (or how close I'll be able to get to doing this) - Theres only
> going to be around 6 or 7 calls to rename() but I must ensure they _all_
> happen before any other process is allowed to run again...

  Take a look at rtprio(2), giving yourself a realtime priority will
guarantee you the CPU until you explicitly release it (or another higher
priority realtime process comes along).  I'm not sure if the same
deadlock potential that exists with giving a process an idle priority
exists due to locking in the kernel, although I see no mention of it in
the man pages.  It's definitely something I'd be wary of, though.

 Regards,
   Tom 


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