Jon Elson wrote: > John Kasunich wrote: > >> I'd rather be obsessively consistent - never disable interrupts and >> never block in a realtime thread. > The problem is OTHER drivers DO disable interrupts, and they > aren't even real time threads!
Minor nitpick: No other HAL drivers disable interrupts. Linux drivers may _think_ they are disabling interrupts, but the underlying RTAI intercepts the cli and sti instructions. RTAI insures that no Linux thread will run while another Linux thread has interrupts disabled. But realtime threads can (and do) run while Linux thinks interrupts are turned off. If Linux only disabled interrupts for very short periods, we wouldn't need RTAI. Linux has made steps in that direction, but its not there yet. Someday I hope we can have an RTAPI layer that lets EMC run on a normal Linux kernel with good (probably never great) realtime performance. Regards, John Kasunich ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
