[LITMUS^RT] New release: 2012.3

[Felipe Cerqueira]

Hi everyone,

I was checking the dev boards with Manohar and we got some kernel
compilation errors in the iMx6 SABRELITE.
Could anyone try to reproduce this cross-compiling 2012.3 for ARM?

1) In sys_release_ts() sync.c,
when litmus_clock() is divided by ONE_MS, it causes undefined reference to
`__aeabi_uldivmod'.
It seems this function is called by the compiler to optimize a division
followed by a modulo.
I had a look at litmus_clock() but I didn't find the modulo operation.
Anyway, I had to change it to this to make it work:

        /* round up to next larger integral millisecond */
        //start_time = ((litmus_clock() / ONE_MS) + 1) * ONE_MS;
        start_time = litmus_clock();
        do_div(start_time,ONE_MS);
        start_time = (start_time + 1) * ONE_MS;

2) The use of cmpxchg in request_exit_np_atomic() makes a __bad_cmpxchg
show up.
__bad_cmpxchg is raised when you try to use cmpxchg with variables of
certain size.
Since it's not implemented in the kernel, we also get a undefined reference
error.

I added the second part of this patch, which implements the BUG() call in
arch/arm/kernel/traps.c:

http://www.spinics.net/lists/arm-kernel/msg65114.html

If this is correct, I can attach the patches later.

Thanks,
Felipe

2012/12/21 Björn Brandenburg <bbb at mpi-sws.org>

> It's my pleasure to announce the release of version 2012.3 of LITMUS^RT
> and related tools.
>
>         https://wiki.litmus-rt.org/litmus/Releases
>
> Here's the list of changes:
>
>         • configurable EDF tie-breaks (choose from one of four methods:
> lateness, normalized tardiness, uniform hashing, PID).
>         • many Feather-Trace improvements, including support for
> userspace-reported system call overhead tracing (via control page)
>         • IRQ counts are now exported to the control page
>         • latency reduction when carrying out synchronous task set releases
>         • fix of preemption logic in P-FP and PSN-EDF plugins
>         • various improvements in the P-FP plugin
>         • misc. bug and compile fixes (esp. on ARM)
>         • liblitmus: new convenience functions lt_sleep() and
> get_nr_ts_release_waiters()
>         • liblitmus: improved test suite
>         • feather-trace-tools: ftsort gained the -v (verbose) and -s
> (simulate) flags, which are useful for outlier debugging
>         • feather-trace-tools: improved outlier detection; statistical
> outlier filtering is no longer required (for details, see B. Brandenburg,
> “Improved Analysis and Evaluation of Real-Time Semaphore Protocols for P-FP
> Scheduling”, RTAS 2013)
>
> Glenn, Jonathan, Chris, and everyone else, thank you very much for sending
> in patches and helping out with testing!
>
> Happy holidays, everyone.
>
> Thanks,
> Björn
>
>
> _______________________________________________
> litmus-dev mailing list
> litmus-dev at lists.litmus-rt.org
> https://lists.litmus-rt.org/listinfo/litmus-dev
>
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