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Subject: Re: [PATCH] tracing, perf: add more power related events
From: Peter Zijlstra <peterz@infradead.org>
To: Arjan van de Ven <arjan@linux.intel.com>
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Date: Wed, 22 Sep 2010 18:43:55 +0200
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On Wed, 2010-09-22 at 09:32 -0700, Arjan van de Ven wrote:
> > What are the apps that are using it? I know about builtin-timechart,
> > pytimechart. Is powertop using this as well?
> 
> powertop 2.x codebase is as well.
> 
> and a bunch of tools we have internal here at Intel.
> 
> the thing with ABIs is that you don't know how many users you have.. at 
> least here you know the lower bound is 3 different tools that are open 
> source.
> .... and likely many local tools that aren't.

These tools should be smart enough to look up the tracepoint name, fail
it its not available, read the tracepoint format, again fail if not
compatible.

I really object to treating tracepoints as ABI and being tied to any
implementation details due to that.

Tools really should be flexible and allow for change.