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Date: Fri, 7 Aug 2009 12:58:35 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
       LKML <linux-kernel@vger.kernel.org>,
       Arnaldo Carvalho de Melo <acme@redhat.com>,
       Mike Galbraith <efault@gmx.de>, Steven Rostedt <rostedt@goodmis.org>,
       Paul Mackerras <paulus@samba.org>,
       Pekka Enberg <penberg@cs.helsinki.fi>,
       Gabriel Munteanu <eduard.munteanu@linux360.ro>,
       Li Zefan <lizf@cn.fujitsu.com>, Lai Jiangshan <laijs@cn.fujitsu.com>
Subject: Re: [PATCH] perfcounters: Support for ftrace event records sampling
Message-ID: <20090807105835.GB24916@elte.hu>
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* Peter Zijlstra <a.p.zijlstra@chello.nl> wrote:

> On Fri, 2009-08-07 at 01:25 +0200, Frederic Weisbecker wrote:
> > This patch brings the kernel side support for ftrace event record
> > sampling.
> > 
> > A new counter attribute is added: PERF_SAMPLE_TP_RECORD which requests
> > ftrace events record sampling.
> > 
> 
> > +	PERF_SAMPLE_TP_RECORD			= 1U << 10,
> 
> I'd really want this thing called PERF_SAMPLE_RAW

yeah, i'd agree. I suggested to Frederic to use TP_RECORD but in 
hindsight we are better off to handle PERF_SAMPLE_RAW as a 'non-ABI' 
embelishment of samples, of not firmly defined content.

In the tracepoint case, that extra raw content is defined by:

   /debug/tracing/events/*/format

and subject to changes.

	Ingo