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Date: Fri, 29 Feb 2008 10:42:35 -0800 (PST)
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To: paulus@samba.org
Cc: mingo@elte.hu, alexey.zaytsev@gmail.com, tglx@linutronix.de,
       linux-kernel@vger.kernel.org
Subject: Re: printk timestamps jumping back and forth in 2.6.25-rc.
From: David Miller <davem@davemloft.net>
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From: Paul Mackerras <paulus@samba.org>
Date: Fri, 29 Feb 2008 22:11:26 +1100

> On powerpc we use the timebase register, which is synchronized across
> CPUs, so if this will add unnecessary overhead, we will want to way to
> turn it off on powerpc (assuming this ends up going upstream).

Similarly on sparc64, all of our TSCs are fully synchronized so
this complexity is completely unnecessary.