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Date: Mon, 14 Jul 2008 15:27:06 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Ingo Molnar <mingo@elte.hu>
cc: linux-kernel@vger.kernel.org, Peter Zijlstra <a.p.zijlstra@chello.nl>,
       Thomas Gleixner <tglx@linutronix.de>,
       Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [git pull] core/percpu for v2.6.27
In-Reply-To: <20080714143413.GA19134@elte.hu>
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On Mon, 14 Jul 2008, Ingo Molnar wrote:
> 
> Please pull the latest core/percpu git tree from:
> 
>    git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git core/percpu

Can you explain what this does and who needs it? The percpu_xchg() looks 
particularly pointless, since it's always a locked SMP-safe instruction on 
x86, so a nonpreemptible load+store will likely be much faster.

			Linus