Re: rt20 scheduling latency testcase and failure data

From: Steven Rostedt
Date: Sat May 13 2006 - 11:39:32 EST



On Sat, 13 May 2006, Mike Galbraith wrote:

> On Sat, 2006-05-13 at 11:20 +0200, Florian Paul Schmidt wrote:
>
> > P.S.: I ran the test a few [20 or so] times and didn't get any failures
> > of the sort you see. Even with a 1ms period:
>
> Something odd happened here... the first time I booted rt21, I could
> reproduce the problem quite regularly. Since reboot though, poof.
>
> Elves and Gremlins.
>

Careful, rt21 has a bug slipped in that might have funny results on SMP
machines:

+ if (!cpus_equal(current->cpus_allowed, irq_affinity[irq]));
+ set_cpus_allowed(current, irq_affinity[irq]);

John (although he later fixed it) added a ; after the if. But the fix is
not yet in Ingo's patch.

-- Steve
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