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Date: Fri, 29 Jul 2005 08:46:00 -0000
From: Andi Kleen <ak@suse.de>
To: Richard J Moore <richardj_moore@uk.ibm.com>
Cc: Andi Kleen <ak@suse.de>,
	Mathieu Desnoyers <compudj@krystal.dyndns.org>,
	Masami Hiramatsu <hiramatu@sdl.hitachi.co.jp>,
	Karim Yaghmour <karim@opersys.com>,
	Masami Hiramatsu <masami.hiramatsu@gmail.com>,
	michel.dagenais@polymtl.ca, Roland McGrath <roland@redhat.com>,
	Satoshi Oshima <soshima@redhat.com>, sugita@sdl.hitachi.co.jp,
	systemtap@sources.redhat.com
Subject: Re: Hitachi djprobe mechanism
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On Fri, Jul 29, 2005 at 09:39:03AM +0100, Richard J Moore wrote:
> 
> 
> 
> 
> that's a very good point. cmpxchg is not always considered for atomic
> storing, though one does have to handle the complication of crossing page
> boundaries.

The CPU cancels and restarts the instruction in this case and everything is 
atomic again.

-Andi