[ cc'd to port-mips - discussion so far is about postgresql
  needing a test-and-set operator ]

Thor Lancelot Simon wrote:

> Test-and-set on MIPS is hard, since the earlier processors don't have an
> atomic TAS or compare-and-swap instruction.  I'd want to be _really_
> sure that the implementation was actually bulletproof before turning
> on the build of a package #'d out for that reason on MIPS -- just
> compiling doesn't seem good enough to me.

Didn't older versions of postgres allow for the use of semaphores
instead of TAS?  I'm download the current package and have a look...

The other option is to implement TAS as a syscall on mips (as at
least Ultrix does).  I put in a half-hearted attempt in the past
to make a generic MI atomic interface - maybe the ``solution'' for
now is a MIPS-only sysarch() call...

Simon.
--
Simon Burge                            <simonb@wasabisystems.com>
NetBSD CDs, Support and Service:    http://www.wasabisystems.com/