Mutex assertion failed with realtime priority threads

["Carlos Pita" <carlosjosepita at gmail dot com>]

Hi all,

I'm not sure if this is a bug in glibc but I'm getting the following error:

pthread_mutex_lock.c:80: __pthread_mutex_lock: Assertion
`mutex->__data.__owner == 0' failed.

from time to time when trying to lock a mutex. It only happens when
one of the threads in the process that manipulates this particular
lock has realtime priority (both SCHED_FIFO or SCHED_RR). If all
threads run with SCHED_OTHER everything goes fine.

I found a couple of related posts about similar problems:

http://sourceware.org/ml/glibc-bugs/2006-10/msg00042.html

http://lists.agnula.org/pipermail/users/2005-January/004798.html

I think the second one is closer to the observed behaviour.

I'm running amd64 ubuntu edgy. My compiler is gcc 4.1.1, glibc version is 2.4.

Any clue will be appreciated.

Thank you in advance.
Regards,
Carlos