> The biggest problems is that some of those machines were R3000-based,
> and R3000 didn't have the ll/sc insns used to perform
> synchronization.

Provided you can defeat any per-cpu cache (ie, provided you can manage
to read and write the actual memory that's shared), you don't need
special instructions.  (Details available on request from me, or in the
synchronization section of at least one OS textbook.  For N CPUs, you
need O(N log N) bits of shared memory per mutex, IIRC.)

					der Mouse

			       mouse@rodents.montreal.qc.ca
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