Re: [PATCH v3 0/6] sched: Add new tracepoints required for EAS testing

[Qais Yousef]

On 06/04/19 23:17, Christoph Hellwig wrote:
> > The following patches add the bare minimum tracepoints required to perform EAS
> > testing in Lisa[1].
> 
> What is EAS?  Whhy is "Lisa" not part of the patch submission?
> submission.

EAS is Energy Aware Scheduling. It was merged in 5.0.

Lisa is a python based testing platform that has dependency on other binaries
like trace-cmd, rt-app, etc. It is not suitable for kernel submission.

Lisa, or any userspace based testing for that matter, requires to know what's
happening inside the scheduler to test its behavior. I don't know know of any
other scheduler centric testing framework. I didn't intend to specify Lisa as
the sole user and reason for these tracepoints, I know others are interested in
these tracepoints in general for anyone who wants to achieve a similar goal of
studying scheduler PELT behavior and how it affects some of the decisions it
makes.

We had a talk in OSPM a couple of weeks ago to cover this topic if you're
interested to learn more

	https://www.youtube.com/watch?v=I_MZ9XS3_zc

> 
> > It is done in this way because adding new TRACE_EVENTS() is no longer accepted
> > AFAIU.
> 
> Huh?  We keep adding trace events all the time.  And they actually
> are useful because they are testable.
> 
> This series on the other hand adds exports not used in tree, which is
> a big no-go.

I see that Peter has already covered this part.

Thanks

--
Qais Yousef