Re: [PATCH 3/4] sched/deadline: Tracepoints for deadline scheduler

From: Ingo Molnar
Date: Wed Feb 24 2016 - 03:48:33 EST

* Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> On Tue, 23 Feb 2016 11:44:08 +0100
> Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> > No it very much illustrates the problem and is a very clear indication
> > that tracepoints are an ABI.
> Yes they are. But note, they can change if nobody notices ;-)

Which is rather seldom for something as high profile as core scheduler
tracepoints ...

You can be cavalier about tracepoints in subsystems where the tracepoints are at
most used by the maintainers with specialized, closely maintained tooling that is
easy to change. Not so much about scheduler tracepoints which are being widely
utilized by various projects.