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Date: Thu, 14 May 2009 07:05:15 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Peter Zijlstra <peterz@infradead.org>
CC: Jeremy Fitzhardinge <jeremy@goop.org>, Ingo Molnar <mingo@elte.hu>,
       "Xin, Xiaohui" <xiaohui.xin@intel.com>, "Li, Xin" <xin.li@intel.com>,
       "Nakajima, Jun" <jun.nakajima@intel.com>, Nick Piggin <npiggin@suse.de>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Xen-devel <xen-devel@lists.xensource.com>,
       rostedt <rostedt@rostedt.homelinux.com>
Subject: Re: Performance overhead of paravirt_ops on native identified
References: <4A0B62F7.5030802@goop.org>  <4A0B6F9C.4060405@zytor.com> <1242289506.6642.901.camel@laptop>
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Peter Zijlstra wrote:
> 
> This sounds remarkably like what the dynamic function call tracer does.
> 

I'm sure this has been invented before... probably more than once.  Far
too many things we invent don't get generalized.

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.