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Date: Wed, 19 May 2010 09:21:40 +0200
From: Frederic Weisbecker <fweisbec@gmail.com>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>, Paul Mackerras <paulus@samba.org>,
       Arnaldo Carvalho de Melo <acme@infradead.org>,
       Steven Rostedt <rostedt@goodmis.org>,
       Thomas Gleixner <tglx@linutronix.de>, linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH 5/5] perf: Implement perf_output_addr()
Message-ID: <20100519072138.GC5704@nowhere>
References: <20100518133258.000434886@chello.nl> <20100518133726.214318408@chello.nl>
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On Tue, May 18, 2010 at 03:33:03PM +0200, Peter Zijlstra wrote:
> perf_output_addr() will, for space allocated using PO_LINEAR, allow
> one to get a linear address for writing its data to.
> 
> Tracepoints tend to want to do this, although when there is need to
> multiplex the events it is of course possible that each event will get
> different data due to having to construct the event multiple times.
> 
> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
> ---


I'm still not sure what you mean here by this multiplexing. Is
this about per cpu multiplexing?

There is another problem. We need something like
perf_output_discard() in case the filter reject the event (which
must be filled for this check to happen).