[LTP] [PATCH] [RFC] syscalls/perf_event_open02: Fix failures

Cyril Hrubis chrubis@suse.cz
Thu May 3 10:49:31 CEST 2018

> The testcase was failing randomly, it could be reproduced easily when
> the machine is under load. To reproduce the issue just run a few
> dd if=/dev/zero of=/dev/null to saturate your CPUs.
> It has been sugessted that the reason for the failure are rounding
> errors caused by a frequent preemption. I haven't got a definitive
> answer from kernel devs for this but it's true that changing the process
> pritority to realtime SCHED_FIFO for the measurement does fix the issue.
> So we either delete the test or apply this patch.

Any comments for this patch?

I would like to have this sorted out before the release...

Cyril Hrubis

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