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Subject: Re: [RFC][PATCH 2/3] perf: Take a hot regs snapshot for trace
 events
From: Steven Rostedt <rostedt@goodmis.org>
Reply-To: rostedt@goodmis.org
To: Peter Zijlstra <peterz@infradead.org>
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On Wed, 2010-03-03 at 18:16 +0100, Peter Zijlstra wrote:

> > This is what I actually was wondering about. Why is it a "perf only"
> > trace point instead of a TRACE_EVENT()?
> 
> Because I wanted to make perf usable without having to rely on funny
> tracepoints. That is, I am less worried about committing software
> counters to ABI than I am about TRACE_EVENT(), which still gives me a
> terribly uncomfortable feeling.
> 
> Also, building with all CONFIG_TRACE_*=n will still yield a usable perf,
> which is something the embedded people might fancy, all that TRACE stuff
> adds lots of code.

We could make TRACE_EVENT() into a perf only trace point with
CONFIG_TRACE_*=n. 

Just saying that it would be nice if ftrace could also see page faults
and such.

-- Steve