kernel configuration

[Chuck Swiger]

On Jan 15, 2009, at 11:31 AM, Dan Nelson wrote:
> Actually, those functions are only enabled if the CPU is truly a
> 586-class processor.  See /sys/i386/isa/npx.c , the npx_attach()
> function.  There is a test for cpu_class==CPUCLASS_586, while most
> modern CPUs are CPUCLASS_686.


Thanks for the additional feedback, Dan.  I remember some weirdness  
around things like the VIA C3 "Centaur" processors, which had CMOV  
feature and claimed to be a 686, but lacked SSE...not that those were  
an especially common case, but I still have one floating around.

I see 686- and SSE2-optimized pagezero routines in support.s, but I  
don't see equivalents for bzero, bcopy, and copyin/copyout.  Is  
something like generic_bzero() faster on a 686-class CPU than  
i586_bzero() would be?

Regards,
-- 
-Chuck