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Subject: Re: SCHED_RR/SCHED_FIFO and kernel threads?
From: Lee Revell <rlrevell@joe-job.com>
To: Patrik =?ISO-8859-1?Q?H=E4gglund?= <patrik.hagglund@bredband.net>
Cc: linux-kernel@vger.kernel.org, Steven Rostedt <rostedt@goodmis.org>,
       Chris Friesen <cfriesen@nortel.com>
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Date: Tue, 21 Jun 2005 20:13:57 -0400
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On Wed, 2005-06-22 at 00:18 +0200, Patrik Hägglund wrote:
> The only clean solution is probably to have priorities that are 
> exclusively reserved for use by the kernel. I saw that kernel threads
> in LynxOS may use a priority of 1/2 above of the user-space tasks it 
> serves. This seems like a good solution to the problem. 

No, it's not, because some SCHED_FIFO/SCHED_RR threads do not need any
kernel services, and are perfectly happy with stalling the rest of the
kernel until they're done.

Lee