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To: Christoph Lameter <clameter@sgi.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/7] Simple Performance Counters: x86_64 support
References: <11859243121617-git-send-email-clameter@sgi.com>
From: Andi Kleen <andi@firstfloor.org>
Date: 01 Aug 2007 12:53:45 +0200
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Christoph Lameter <clameter@sgi.com> writes:

> Export cycles_to_ns (after renaming the cycles_2_ns to cycles_to_ns to be
> conforming to other arches).

This function is broken in some cases (e.g Opteron with powernow or
AMD dual core or older Intel systems) and going away.  The TSCs tick
with different frequencies on different CPU there. In general i would
recommend to only report cycles.

-Andi