Jan Kiszka wrote:
> Gilles Chanteperdrix wrote:
>> Jan Kiszka wrote:
>> > Jeroen Van den Keybus wrote:
>> > > Gilles,
>> > >
>> > >
>> > > I cannot reproduce those messages after turning nucleus debugging on.
>> > > Instead, I now either get relatively more failing mutexes or even hard
>> > > lockups with the test program I sent to you. If the computer didn't
>> crash,
>> > > dmesg contains 3 Xenomai messages relating to a task being movend to
>> > > secondary domain after exception #14. As when the computer crashes: I
>> have
>> > > written the last kernel panic message on a paper. Please tell if you
>> want
>> > > also the addresses or (part of) the call stack.
>> > >
>> > > I'm still wondering if there's a programming error in the mutex test
>> > > program. After I sent my previous message, and before I turned nucleus
>> > > debugging on, I managed (by reducing the sleeptimes to max. 5.0e4) to
>> > > fatally crash the computer, while spewing out countless 'scheduling
>> while
>> > > atomic messages'. Is the mutex error reproducible ?
>> >
>> > I was not able to crash my box or generate that scheduler warnings, but
>> > the attached patch fixes the false positive warnings of unlocked
>> > mutexes. We had a "leak" in the unlock path when someone was already
>> > waiting. Anyway, *this* issues should not have caused any other problems
>> > then the wrong report of rt_mutex_inquire().
>>
>> Actually the patch seem insufficient, the whole block :
>> {
>> xnsynch_set_owner(&mutex->synch_base,&task->thread_base);
>> mutex->owner = task;
>> mutex->lockcnt = 1;
>> goto unlock_and_exit;
>> }
>>
>> should be done after xnsynch_sleep_on in rt_mutex_lock.
>>
>
> Damn, of course - except for "mutex->owner = task". Then this missing
> xnsync_set_owner() may have caused serious issues? Will test...Correction: xnsynch_wakeup_one_sleeper() updates synch->owner, so all fine with my patch in this regard. I guess it is really some migration issue again. Jan
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