Jim Donelson wrote: > I wonder why (on an SP machine) you don't just disable interrupts for > a few instructions and give yourself an atomic dec?
Yes, that's fine. However, it's not secure to allow userspace to disable interrupts(*), so we've talked about a custom instruction which lets userspace disable interrupts for a maximum of 3/4 instructions, then the hardware forces them on again. (*) with an MMU; without an MMU there's no security anyway so it doesn't matter as much. Personally I think the ARM method is nicest because it doesn't need any special hardware, but time-limited interrupt disabling may be a little bit faster, or slower, depending on the architecture. -- Jamie _______________________________________________ uClinux-dev mailing list uClinux-dev@uclinux.org http://mailman.uclinux.org/mailman/listinfo/uclinux-dev This message was resent by uclinux-dev@uclinux.org To unsubscribe see: http://mailman.uclinux.org/mailman/options/uclinux-dev
