2.6.0-test2-mm5 x86-64 link errors

I get to play with an opteron for a bit, so I'm going to try 2.6 on it, but test2-mm5 seems to compile fine, but when it goes to link it, it gives these errors:

LD init/built-in.o
LD .tmp_vmlinux1
kernel/built-in.o(.text+0x359): In function `try_to_wake_up':
: undefined reference to sched_clock' kernel/built-in.o(.text+0x3b9): In function try_to_wake_up':
: undefined reference to sched_clock' kernel/built-in.o(.text+0x1150): In function load_balance':
: undefined reference to sched_clock' kernel/built-in.o(.text+0x1ae3): In function schedule':
: undefined reference to sched_clock' kernel/built-in.o(.text+0x3a22): In function move_task_away':
: undefined reference to sched_clock' kernel/built-in.o(.text+0x56cc): more undefined references to sched_clock' follow
make: *** [.tmp_vmlinux1] Error 1

Ingo's scheduler patch requires that the architecture provide a sched_clock() function which returns nanoseconds. We only have ia32, ia64, ppc and ppc64 versions thus far.

A lame version is to just add

unsigned long long sched_clock(void)

{
	return (unsigned long long)jiffies * (1000000000 / HZ);
}

to arch/<foo>/kernel/timer.c