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

[Petr Vorel]

> Hi!
> > This has improved something, but still observes sporadic fail on RHEL stock
> > kernel.
> > However, both the RHEL RT-kernel and the mainline v6.17-rc4 stock kernel
> > pass.

FYI I run tests all SLES and Tumbleweed versions on non-RT kernels, with -i50,
for both master and your v2 (with enabled non-RT kernels).  All are passing.


* 6.16.3-1 (Tumbleweed, very close to kernel stable - it has very few patches unlike the others)
CONFIG_PREEMPT_VOLUNTARY=y
$ cat /sys/kernel/debug/sched/preempt
none (voluntary) full lazy

SLES (these are heavily modified)

* 6.4
* 5.14
CONFIG_PREEMPT_VOLUNTARY=y
$ cat /sys/kernel/debug/sched/preempt
(none) voluntary full

* 5.3
* 4.12
* 4.4
CONFIG_PREEMPT_NONE=y
(/sys/kernel/debug/sched/preempt not enabled)

Later I recheck what was your config which breaks it.

> Maybe add a short usleep() before the referee sets the kickoff_flag so
> that the system has more time to shuffle processes?

+1

Kind regards,
Petr