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Subject: Re: [PATCH] tracing, perf: add more power related events
From: Peter Zijlstra <peterz@infradead.org>
To: Ingo Molnar <mingo@elte.hu>
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Date: Wed, 22 Sep 2010 20:30:33 +0200
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On Wed, 2010-09-22 at 20:23 +0200, Ingo Molnar wrote:
> * Steven Rostedt <rostedt@goodmis.org> wrote:
> 
> > We could add a TRACE_EVENT_ABI() as Ingo has been suggesting. [...]
> 
> That would be rather useful.
> 
> We could still be flexible about experimental tracepoints (they dont 
> hurt), but apps should stick to ABI bits - or at least not complain when 
> non-ABI tracepoints change for good reasons. (arbitrary, avoidable 
> changes are still bad obviously, regardless of the type of the 
> tracepoint)
> 
> We'd be more stringent with marking tracepoints an ABI.
> 
> So yes, this would be lovely to have.

Why? As long as we mandate that apps need to fully parse the format
stuff anyway, it doesn't buy us much.