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Date: Sat, 28 Sep 2002 15:54:18 +0100
From: John Levon <movement@marcelothewonderpenguin.com>
To: linux-kernel@vger.kernel.org
Subject: Re: Sleeping function called from illegal context...
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On Fri, Sep 27, 2002 at 08:51:30PM -0400, Robert Love wrote:

> Note this has nothing to do with kernel preemption.  IDE explicitly
> sleeps while purposely holding a lock.
> 
> It is just we do not have the ability to measure atomicity w/o
> preemption enabled - e.g. the debugging only works when it is enabled.

Would it be particularly difficult to separate this debug tool from the
feature ? Surely we could make it so that CONFIG_PREEMPT depends on
CONFIG_MIGHT_SLEEP or whatever, and just adds the actual ability to
reschedule.

I have a bit of a problem with __might_sleep because I call sleepable
stuff holding a spinlock (yes, it is justified, and yes, it is safe
afaics, at least with PREEMPT=n)

regards
john

-- 
"When your name is Winner, that's it. You don't need a nickname."
	- Loser Lane
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