Messages in this thread | | | From | Rick Niles <> | Subject | Sub jiffy delay? | Date | Wed, 23 Nov 2005 15:39:17 -0500 (EST) |
| |
I need to service a piece of hardware about every 400-500 microseconds, but I really don't want to change the value of HZ, which in my version of the 2.6 kernel is 1000. The hardware doesn't have an interrupt so the nasty hack I've been doing is to service the hardware repeatedly in a loop for about 600 microseconds by watching the do_gettimeofday(), set a timer for the next jiffy and repeat. This leaves less than 400 microseconds / millisecond for the kernel and anything else on the system to run.
Obviously, this sucks, but it does work. I am working with the hardware guy to add an interrupt to the hardware. However, I don't want every user of the hardware without the interrupt to have to rebuild the kernel with a different value of HZ. So does anyone have any better ideas on what I can do?
Thanks, Rick Niles. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |