Re: [RFC][PATCH 1/5] [PATCH 1/5] events: Add EVENT_FS the event filesystem

Peter Zijlstra
2010-11-17T15:36:09Z

On Wed, 2010-11-17 at 10:16 -0500, Steven Rostedt wrote:
> What about a tool that picks up tracepoints that were only used by a
> developer for in-field debugging, and then that tracepoint disappears
> because of a design change. Is it OK for that tool to break with it?
>
> Do all tools that use tracepoints require a "check" feature?

Not sure what you mean with a 'check' feature, but I do think its useful
to tools authors to clearly delineate between stable and debug
tracepoints, that also facilitates

> I guess the problem is that creators of the tools to analyze the kernel
> have no idea of what they can count on and what they can't. Do we need a
> process to have these tool creators request to developers to "keep this
> tracepoint"?

the process mentioned here, if they cannot find the data they want
through existing stable tracepoints they have to request it, or
otherwise clearly suffer breakage whenever we feel like changing stuff.

A nice aspect of devs coming to us and requesting data is that we get a
fairly good idea of what tools are available and get to discuss the
problem they're trying to solve.

Esp. that latter point is a very good one imho, we might have a totally
different view on some of the problems :-)