From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: [patch 0/3] [Announcement] Performance Counters for Linux
Date: Fri, 05 Dec 2008 09:03:36 +0100
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To: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>, Thomas Gleixner <tglx@linutronix.de>, LKML <linux-kernel@vger.kernel.org>, linux-arch@vger.kernel.org, Andrew Morton <akpm@linux-foundation.org>, Stephane Eranian <eranian@googlemail.com>, Eric Dumazet <dada1@cosmosbay.com>, Robert Richter <robert.richter@amd.com>, Arjan van de Veen <arjan@infradead.org>, Peter Anvin <hpa@zytor.com>, Steven Rostedt <rostedt@goodmis.org>, David Miller <davem@davemloft.net>

On Fri, 2008-12-05 at 18:57 +1100, Paul Mackerras wrote:
> Peter Zijlstra writes:
> 
> > So, while most people would not consider two consecutive read() ops to
> > be close or near the same time, due to preemption and such, that is
> > taken away by the fact that the counters are task local time based - so
> > preemption doesn't affect thing. Right?
> 
> I'm sorry, I don't follow the argument here.  What do you mean by
> "task local time based"?

time only flows when the task is running.