Re: [RFC PATCH 2/5] tracing/events: nicer print format for parsing

[Mathieu Desnoyers <compudj@krystal.dyndns.org>]

* Steven Rostedt (rostedt@goodmis.org) wrote:

> Again, anyone have any better ideas?
> 
> -- Steve
> 

Hi Steven,

sorry I don't have much time to look into this. My ph.d. thesis is due
for july 5th..

I just wanted to let you now that I wrote a very simple XML parser in
the early days of LTTng. I dumped it in favor of the trace_mark() format
strings, but it really gave much more flexibility to describe events,
including nested structures, unions... etc.

It's written in C with almost no external dependency. The goal was to
make it so it could be acceptable in the kernel tree. I think you might
want to have a quick look at it. It generated the probe callbacks which
were, at the time, inlines. Since then I realised that inlining the
tracer code in the kernel call site pollutes the i-cache, so it's not
the way I would deal with code generation today, but those are minor
details.

It would need a cleanup. I did not write the original version of this
code, but rather kicked it until it worked as I wanted it. It worked
with the old LTTng versions:

http://www.lttng.org/files/packages/genevent-0.35.tar.gz

The package contains sample XML files.

Good luck,

Mathieu


-- 
Mathieu Desnoyers
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