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Subject: Re: atomic copy_from_user?
From: Rob Love <rml@ximian.com>
To: Joe Korty <joe.korty@ccur.com>
Cc: William Lee Irwin III <wli@holomorphy.com>,
       Albert Cahalan <albert@users.sourceforge.net>,
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On Mon, 2003-12-22 at 16:22, Joe Korty wrote:

> I am guessing that nowdays even when preemption is disabled one can
> find preempt_count still being used somewhere.  Otherwise it would be
> better to replace all uses of inc_preempt_count() with
> preempt_disable() and dec_preempt_count() with preempt_enable().

Right.  So why did you make this patch? :)

inc_preempt_count() and dec_preempt_count() are for use when you
_absolutely_ must manage the preemption counter, regardless of whether
or not kernel preemption is enabled.

They are used for things like atomic kmaps.

	Rob Love