Jamie Lokier wrote: > > - Do you have atomic instructions. > - Do you have one CPU or multiple CPUs.
Of course you are right. > > Let's assume you have a single CPU and no special atomic instructions. > > - Copy the trick used on ARM to implement atomic-compare-exchange > in the vsyscall page, without disabling interrupts. Modern ARM variants have "load-Link / Store-Conditional" instructions. NIOS does not have those and I don't suppose Microblaze has. > > The vsyscall trick is a good one, and works with/without MMU, and > with/without permission to disable interrupts in userspace. It's fast > too. I recommend reading the code. It's only a few instructions. > I'll do so. Does the "vsyscall trick" not force a trap and thus Kernel interaction ? Thanks ! -Michael _______________________________________________ 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
