Jan Kiszka wrote: > Gilles Chanteperdrix wrote: >> Jan Kiszka wrote: >>> To improve robustness of the fast mutex implementation in POSIX (and >>> later on in native), it is better to track the mutex owner by handle >>> instead of kernel object pointer. Therefore, this patch changes >>> __xn_sys_current (xeno_set_current) so that it returns >>> xnthread_handle(current_thread). It furthermore converts the POSIX mutex >>> implementation to pick up and store the lock owner as handle in the >>> kernel/user-shared mutex. Finally it ensures that all skins (except for >>> RTDM which must not mess around with foreign skins anyway) add their >>> threads to the registry so that at least anonymous handles are >>> available. >>> >>> As the value stored in the mutex variable is now an integer, we can >>> switch over to xnarch_atomic_t, removing all atomic_intptr users. >> The current implementation allows RTDM threads to use POSIX skin >> mutexes. I do not see why this should change. > > Such mixup might technically be possible now. But there is neither a > need nor does it make the resulting driver more portable. I don't want > to introduce needless thread registration to RTDM just to cover > theoretical use cases that should not exist in the first place. > > Nevertheless, some sanity check will have to be added to the > to-be-written generic xnsynch support to catch missing thread handles. > That make sense for checking future skin implementation as well.
That is overhead in the hot path, whereas adding the thread registration takes place in a non hot path. -- Gilles. _______________________________________________ Xenomai-core mailing list Xenomaiemail@example.com https://mail.gna.org/listinfo/xenomai-core