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Subject: Re: [RFC][PATCH 1/5] [PATCH 1/5] events: Add EVENT_FS the event
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From: Peter Zijlstra <peterz@infradead.org>
To: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>, Greg KH <gregkh@suse.de>,
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        Lin Ming <ming.m.lin@intel.com>,
        Arnaldo Carvalho de Melo <acme@redhat.com>
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Date: Wed, 17 Nov 2010 16:16:49 +0100
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On Wed, 2010-11-17 at 16:03 +0100, Ingo Molnar wrote:
> I think Arjan's complaints at the KS stemmed from prior sporadic declarations on 
> lkml that there is no tracepoint ABI _at all_, and that powertop/latencytop could 
> break anytime. 

And it will, afaik Arjan refused to even parse the format file which is
part of the tracepoint abi and I'll be changing those for the scheduler.

I really object to not being able to make sane changes just because some
tool is too lazy to even implement the full ABI that was exposed.


> I think Arjan's complaints at the KS stemmed from prior sporadic declarations on 
> lkml that there is no tracepoint ABI _at all_, and that powertop/latencytop could 
> break anytime. 

I fully intent to break powertop/latencytop if they refuse to use the
format file, deal with it.

Also, in the unlikely event we need to re-order the task->state bits
I'll do so without a moments hesitation, regardless of who consumes them
through the scheduler tracepoints, that's simply not stuff that should
be tied down.

The same for anything that tries to interpret task->prio through the
tracepoints.