Here's another feature I'd like to add to MCA support; the ability
to detect a flood of CMCs and switch to polling mode for retrieving
CMC logs.  Once no more CMC logs are found, return to and interrupt
driven handler.  If the flood threshold is never reached, the CMC
handler simply behaves as it does today.

   It's useful to get the CMC logs to know that something isn't
quite right, but if you end up with some bad memory it's too easy for
them to interfere with useful work.  I've tested this on an HP rx2600,
with a known bad DIMM.  This DIMM acts like it has a completely dead
DRAM on it.  With the current CMC handler, once I hit that range of
memory addresses, the system essentially dies, constantly handling
CMC errors.  With this patch, the system hits the threshold quickly,
but remains functional with no performance degredation once in polling
mode.  This patch applies against linux-2.4.20-ia64-021210 and 
includes:

 - Switching CMCs to polling mode at predeterimined threshold
 - If polling for CPEs, poll on all processors
 - Fix timestamp on log output