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Date: Tue, 13 Jul 2004 15:44:48 -0700
From: Andrew Morton <akpm@osdl.org>
To: Andrea Arcangeli <andrea@suse.de>
Cc: paul@linuxaudiosystems.com, rlrevell@joe-job.com,
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       linux-kernel@vger.kernel.org
Subject: Re: [linux-audio-dev] Re: [announce] [patch] Voluntary Kernel
 Preemption Patch
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Andrea Arcangeli <andrea@suse.de> wrote:
>
> On Tue, Jul 13, 2004 at 03:25:32PM -0700, Andrew Morton wrote:
> > 	local_irq_disable();
> > 	<fiddle with per-cpu stuff>
> > 	function_which_calls_cond_resched();
> > 	<fiddle with per-cpu stuff>
> > 	local_irq_enable();
> > 
> > then we want might_sleep() to warn about the bug.
> 
> might_sleep currently _doesn't_ warn about any bug in the above case I
> quoted.
> 
> the kmalloc example is trapped instead.

Yeah, I know.  might_sleep() in cond_resched() makes sense.

> >From my part I don't like anybody to call schedule with irq disabled

I'd agree with that.  But when I "fixed" it, Ingo unfixed it again and I
didn't have sufficiently strong feelings either way to object.