[Patch] tsc-disable_A5

From: john stultz (johnstul@us.ibm.com)
Date: Fri Jun 14 2002 - 13:35:26 EST

Hey Marcelo,
        I know its probably poor form to send this out so close to -rc, but I
figured I might as well give it a shot. I'll happily resubmit this for
the .20pre series later if you'd prefer.

This patch disables the TSCs when compiled for Multiquad NUMA hardware.
Due to the slower interconnect, the TSCs aren't being synced properly at
boot time. Even if they were synced, since the different nodes are
driven by different crystals, the TSCs still drift.

This results in sequential calls to gettimeofday to return
non-sequential time values. By disabling the TSCs on these boxes, it
forces gettimeofday to use the PIC clock instead, fixing the problem.

Let me know if you have any comments.


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