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Date: Wed, 25 Feb 2009 14:02:02 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Arnaldo Carvalho de Melo <acme@redhat.com>,
       Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH 1/2] tracing/core: introduce per cpu tracing files
Message-ID: <20090225130202.GH26273@elte.hu>
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* Frederic Weisbecker <fweisbec@gmail.com> wrote:

> Impact: split up tracing output per cpu

> So this patch creates a new directory inside /debug/tracing 
> (provided you have a debugfs mountpoint on /debug). Inside 
> this directory, you will now find one trace_pipe file, one 
> trace file and one latency_trace file per cpu. Which means if 
> you have two cpus, you will have:
> 
> trace0
> trace1
> trace_pipe0
> trace_pipe1

Very nice! I've applied your patches to tip:tracing/ftrace.

Could you please do one more tweak? The /debug/tracing/per_cpu/ 
directory looks a bit cluttered on a 16-way box. It would be a 
nicer structure to have per CPU directories, i.e.:

 /debug/tracing/per_cpu/cpu0/trace
 /debug/tracing/per_cpu/cpu0/trace_pipe
 /debug/tracing/per_cpu/cpu1/trace
 /debug/tracing/per_cpu/cpu1/trace_pipe

etc.

Besides being easier to handle, this also makes it easy to 
extend the list of per CPU attributes as well, without 
cluttering the /debug/tracing/per_cpu/ directory.

	Ingo