Re: [RFC] tracefs

Ingo Molnar
2009-10-23T05:32:49Z

* Greg KH <greg@kroah.com> wrote:

> Hi all,
>
> At LinuxCon this year, Steven and I talked about moving the debugfs
> usage in the tracing core to a stand-alone filesystem to give the
> ability to start to lock down the api so that people an count on what
> is going on in the tracing userspace interface.

What we want to move out initially (and i talked to Steve and Frederic
about that a few weeks ago) is the event description bits - the format
stuff in /debug/tracing/events/ - but definitely not all the other,
rather messy and ad-hoc APIs.

_No way_ do we want to tie down the pretty-printing ftrace details as an
ABI. We promised that when ftrace went upstream and all the details are
way too messy to be exposed in an ABI alike matter (and yes, consider
this a NAK Steve ;-).

We want a _very_ careful exporting of certain pieces of information that
helps syscall-exposed perf events bits, and to improve the quality of
interfaces while we do that.

Ingo