Date: Thu, 7 Apr 2005 16:54:12 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Keith Owens <kaos@sgi.com>
Cc: linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: 2.6.12-rc2 in_atomic() picks up preempt_disable()
Message-ID: <20050407145412.GA6520@elte.hu>
References: <13730.1112868613@kao2.melbourne.sgi.com>
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* Keith Owens <kaos@sgi.com> wrote:

> 2.6.12-rc2, with CONFIG_PREEMPT and CONFIG_PREEMPT_DEBUG.  The 
> in_atomic() macro thinks that preempt_disable() indicates an atomic 
> region so calls to __might_sleep() result in a stack trace. 
> preempt_count() returns 1, no soft or hard irqs are running and no 
> spinlocks are held.  It looks like there is no way to distinguish 
> between the use of preempt_disable() in the lock functions (atomic) 
> and preempt_disable() outside the lock functions (do nothing that 
> might migrate me).

preempt_disable() sections are just as much atomic as spinlocked 
regions. Like the name suggests it.

	Ingo
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