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Date: Sun, 29 May 2011 22:17:13 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH 3/5] v2 seccomp_filters: Enable ftrace-based system call
	filtering
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Cc: linux-mips@linux-mips.org, linux-sh@vger.kernel.org,
	Frederic Weisbecker <fweisbec@gmail.com>,
	Heiko Carstens <heiko.carstens@de.ibm.com>,
	Oleg Nesterov <oleg@redhat.com>, David Howells <dhowells@redhat.com>,
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	Russell King <linux@arm.linux.org.uk>, x86@kernel.org,
	James Morris <jmorris@namei.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
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* Peter Zijlstra <peterz@infradead.org> wrote:

> But face it, you can argue until you're blue in the face,

That is not a technical argument though - and i considered and 
answered every valid technical argument made by you and Thomas.
You were either not able to or not willing to counter them.

> [...] but both tglx and I will NAK any and all patches that extend 
> perf/ftrace beyond the passive observing role.

The thing is, perf is *already* well beyond the 'passive observer' 
role: we already generate lots of 'action' in response to events. We 
generate notification signals, we write events - all of which can 
(and does) modify program behavior.

So what's your point? There's no "passive observer" role really - 
it's apparently just that you dislike this use of instrumentation 
while you approve of other uses.

Thanks,

	Ingo