[LTP] [PATCH v2] sched_football: synchronize with kickoff flag to reduce skew

[Cyril Hrubis]

Hi!
> >  static void do_setup(void)
> >  {
> > +	if (!tst_check_preempt_rt())
> > +		tst_brk(TCONF, "Test requires real-time kernel");
> 
> I understood Cyril is really suggesting to keep it [1]. I would also vote to
> keep it (we still have some time to see if it got fixed before release).
> 
> I know we had this discussion in the past (some of your colleague suggesting it
> should not be run on non-RT kernel), so I'm not pushing for it.

I stil do not understand reasons for disabling the test. The POSIX
realtime schedulling classes have to work properly regardless of the
kernel flavor. Why should we turn the test off on non-rt kernel then?

It may make sense to prolong the settling period for non-rt something
as:

...
	if (tst_check_preempt_rt()
		settling_period = 20000;
	else
		settling_period = 200000;


...
	usleep(settling_period);
...


In order to make sure non-rt scheduller has enough time to shuffle the
processes around the available CPUs. But that should be the only
difference.

-- 
Cyril Hrubis
chrubis@suse.cz