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Date: Mon, 25 Feb 2002 15:01:04 -0500 (EST)
From: Bill Davidsen <davidsen@tmr.com>
To: Paul Jackson <pj@engr.sgi.com>
cc: linux-kernel <linux-kernel@vger.kernel.org>,
        lse-tech@lists.sourceforge.net
Subject: Re: [Lse-tech] Re: [PATCH] O(1) scheduler set_cpus_allowed for non-current tasks
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On Wed, 20 Feb 2002, Paul Jackson wrote:

> I see three levels of synchonization possible here:
> 
> 1) As Erich did, use IPI to get immediate application
> 
> 2) Wakeup the target task, so that it will "soon" see the
>    cpus_allowed change, but don't bother with the IPI, or
> 
> 3) Make no effort to expedite notifcation, and let the
>    target notice its changed cpus_allowed when (and if)
>    it ever happens to be scheduled active again.

(3) looks good, if the process isn't running it makes little difference on
which CPU it doesn't run. Would probably be enough to ensure that if it is
scheduled active the change is noted at that time. "Eventually" is a good
time to do this, when going through schedule code anyway.

-- 
bill davidsen <davidsen@tmr.com>
  CTO, TMR Associates, Inc
Doing interesting things with little computers since 1979.

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