Re: [RFC] tracefs

[Frederic Weisbecker <fweisbec@gmail.com>]

On Fri, Oct 23, 2009 at 07:32:37AM +0200, Ingo Molnar wrote:
> 
> * 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


I guess the first bits that need to be exported are the TRACE_EVENT_ABI.
But even before that, we need to ensure we have a final version of
the trace events description.