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Date: Wed, 19 May 2010 09:14:10 +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: [PATCH 0/5] Optimize perf ring-buffer
Message-ID: <20100519071408.GA5704@nowhere>
References: <20100518133258.000434886@chello.nl>
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On Tue, May 18, 2010 at 03:32:58PM +0200, Peter Zijlstra wrote:
> This patch-set optimizes the perf ring-buffer by removing IRQ disable and 
> all LOCK ops from the fast paths.
> 
> There's also an RFC patch that adds perf_output_addr() which will allow
> you to write directly to the buffer, however I'm not sure how to go
> about using it for the trace events since we need to multiplex event --
> there is no single copy of the actual event.


What do you mean by the fact we need to multiplex event?