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Date: Wed, 5 Oct 2011 14:39:07 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: "linux-mm@kvack.org" <linux-mm@kvack.org>,
        linux-arch <linux-arch@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH] mm, arch: Complete pagefault_disable abstraction
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On Wed, 05 Oct 2011 15:09:29 +0200
Peter Zijlstra <peterz@infradead.org> wrote:

> Currently we already have pagefault_{disable,enable}() but they're
> nothing more than a glorified preempt_{disable,enable}().

That's not very accurate or useful.  Unlike preempt_disable(),
pagefault_disable() will raise the preempt count when CONFIG_PREEMPT=n.