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Date: Mon, 4 Mar 2002 16:41:30 -0800
From: Mike Fedyk <mfedyk@matchmail.com>
To: Robert Love <rml@tech9.net>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] preempt-kernel on 2.4.19-pre2-ac2 bugfix
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On Mon, Mar 04, 2002 at 07:23:10PM -0500, Robert Love wrote:
> The same schedule_tail bug affecting 2.5 affects 2.4 with O(1).  I.e.,
> 2.4.19-pre2-ac2.
> 
> In recent O(1) scheduler releases, an optimization was made that removed
> schedule_tail from UP kernels.  This causes the initial preempt_count of
> a new task, which starts at 1, to never decrement to zero and thus never
> become preemptible.  CONFIG_PREEMPT requires schedule_tail, too.
> 
> Users of 2.4+O(1)+preempt (i.e. -ac) should use this patch:
>

I believe you want to say that O(1)sched is in -ac, and this patch will add
preempt on top of that, not that preempt is already in -ac (unless I missed
something...)

Mike
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