[LITMUS^RT] running a task as its execution time

[Jonathan Herman]

I can look at this tonight (I am now PST, so that will be in 12 hours).

On Wed, May 30, 2012 at 5:42 AM, Björn Brandenburg <bbb at mpi-sws.org> wrote:

>
> On Apr 30, 2012, at 4:11 PM, Giovani Gracioli wrote:
> > I am getting successive kernel panics at the same litmus/budget.c line
> 65 using GSN-EDF scheduler. The application code (test.c) and the task sets
> are attached. You can run ./test 125 125_tasks_litmus.txt for 125 tasks or
> 150 150_tasks_litmus.txt for 150 tasks.
> >
> > The processor is an intel i7-2600 with 4 cores and 2 threads per core.
>
> I am able to reproduce the problem. After some debugging, I think this is
> what happens:
>
> 1) A task with precise enforcement has zero budget
> 2) It gets unlinked before the timer is handled. The budget/job completion
> is not processed because of this check in GSN-EDF's schedule():
>
> 471:        if (!np && (out_of_time || sleep) && !blocks && !preempt)
> 472:                job_completion(entry->scheduled, !sleep);
>
> 3) The task gets relinked elsewhere.
> 4) When it is scheduled, the BUG_ON() triggers.
>
> However, just removing the !preempt check will cause trouble since timers.
> This is not straightforward.
> I'll continue to investigate tomorrow. In the mean while, suggestions
> anyone? Glenn? Chris? Jonathan?
>
> Thanks,
> Björn
>
>
> _______________________________________________
> litmus-dev mailing list
> litmus-dev at lists.litmus-rt.org
> https://lists.litmus-rt.org/listinfo/litmus-dev
>



-- 
Jonathan Herman
Department of Computer Science at UNC Chapel Hill
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.litmus-rt.org/pipermail/litmus-dev/attachments/20120530/af57bf73/attachment.html>