[project @ 2005-04-05 12:19:54 by simonmar]
Some multi-processor hackery, including - Don't hang blocked threads off BLACKHOLEs any more, instead keep them all on a separate queue which is checked periodically for threads to wake up. This is good because (a) we don't have to worry about locking the closure in SMP mode when we want to block on it, and (b) it means the standard update code doesn't need to wake up any threads or check for a BLACKHOLE_BQ, simplifying the update code. The downside is that if there are lots of threads blocked on BLACKHOLEs, we might have to do a lot of repeated list traversal. We don't expect this to be common, though. conc023 goes slower with this change, but we expect most programs to benefit from the shorter update code. - Fixing up the Capability code to handle multiple capabilities (SMP mode), and related changes to get the SMP mode at least building.