On Wed, Apr 22, 2009 at 04:14:48PM +0200, M. Koehrer wrote: > However, there is one operation mode that uses interrupts to signal > incoming data. The interrupt handler is realized as a tiny kernel > module (that one that provides also the mmap for the user mode > application). Now I am not sure how the signalling of the IRQ from > kernel to user mode could be realized best (in terms of low latency). > > The "classical" approach for this task is to provide a character > driver with a .poll file operation. In Xenomai I could use a semaphore > that was accessible from kernel and user space for this. What is the > best way in the RT_PREEMPT "world"? UIO might be a good choice here, the rest is giving the interrupt handler and the processes the right priorities. rsc -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
