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Date: Thu, 25 Sep 2008 16:33:48 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Ingo Molnar <mingo@elte.hu>
cc: Steven Rostedt <rostedt@goodmis.org>, Martin Bligh <mbligh@google.com>,
       Peter Zijlstra <peterz@infradead.org>, Martin Bligh <mbligh@mbligh.org>,
       linux-kernel@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
       Andrew Morton <akpm@linux-foundation.org>, prasad@linux.vnet.ibm.com,
       Mathieu Desnoyers <compudj@krystal.dyndns.org>,
       "Frank Ch. Eigler" <fche@redhat.com>, David Wilder <dwilder@us.ibm.com>,
       hch@lst.de, Tom Zanussi <zanussi@comcast.net>,
       Steven Rostedt <srostedt@redhat.com>
Subject: Re: [RFC PATCH 1/3] Unified trace buffer
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On Fri, 26 Sep 2008, Ingo Molnar wrote:
> 
> i do not understand this argument of yours. (really)
> 
> 1) is your point that we might lock up?

Have you at all followed the discussion about the people who asked for 
cross-CPU ordering? They wanted not timestamps at all, but global atomic 
counter updates. Which is very reasonable, if timestamps don't work (and 
jiffies certainly doesn't, especially in a NOHZ environment).

IOW, my whole argument is that what tracers want is _not_ the same thing 
as what "sched_clock()" wants.

		Linus