Re: Ftrace plugin for Babeltrace2

[Philippe Duplessis-Guindon <pduplessis@efficios.com>]

From: "Steven Rostedt" <rostedt@goodmis.org>
To: "Philippe Duplessis-Guindon" <pduplessis@efficios.com>
Cc: "linux-trace-devel" <linux-trace-devel@vger.kernel.org>
Sent: Monday, June 1, 2020 2:36:43 PM
Subject: Re: Ftrace plugin for Babeltrace2

On Mon, 1 Jun 2020 12:45:10 -0400 (EDT)
Philippe Duplessis-Guindon <pduplessis@efficios.com> wrote:

>> Hi everyone,
>> 
>> 
>> My name is Philippe and I am an intern at EfficiOs for the summer. This email is

> Hi Philippe!

> I believe we met before. Correct me if I'm wrong.

You must be mistaking me with the other Philippe at EfficiOs. I am an intern who started last month!

>> 
>> to inform you about my summer project, ask for recommendations and your opinion.
>> 
>> 
>> My project will consist of implementing a Babeltrace2 [1] plugin to be able to consume
>> 
>> ftrace traces. The plugin will act as a source component in the babeltrace2 graph system.

> This is awesome!

>> 
>> 
>> I was wondering if you can give me your first thoughts about this project, and
>> 
>> any advice on where to find information to begin with, since I am new to ftrace.
>> 
>> I have already read the doc [2][3][4], but I was wondering if there are more resources
>> 
>> that could help me with my work.
>> 
>> 
>> Also, I was wondering which version of libtraceevent I should use. The one in the kernel,
>> 
>> or the one in the trace-cmd repo? My guess would be to take the one in trace-cmd since
>> 
>> there are more recent commits, but I am asking just to make sure.

> Well it shouldn't matter, as I try to keep the two insync, but because
> of the current environment (COVID-19 and all), I've been falling behind.

Perfect!

> There's talk in moving it out of both the kernel and trace-cmd and make
> libtraceevent a stand alone library. But that will take some
> coordination.

That would be great!

>> 
>> 
>> The major focus of the project will be to match ftrace concepts to babeltrace 2
>> 
>> internal representation.
>> 
>> 
>> [1] https://babeltrace.org/
>> 
>> [2] https://github.com/torvalds/linux/tree/master/tools/lib/traceevent/Documentation
>> 
>> [3] https://git.kernel.org/pub/scm/linux/kernel/git/rostedt/trace-cmd.git/tree/Documentation
>> 
>> [4] https://www.kernel.org/doc/Documentation/trace/ftrace.txt
>> 


> Ideally, we would like to get KernelShark to use babeltrace as well, to
> increase what it can read.

Sounds good, I'll have this in mind while implementing my plugin.

> Thanks for reaching out. If there's anything else you need, please feel
> free to ask.

Thank you,
Philippe