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Subjectboot_cpu_data vs current_cpu_data in voluntary-preempt-2.6.9-rc2-mm1-S1
Ingo,

Your voluntary-preempt-2.6.9-rc2-mm1-S1 patch contains this change

@@ -34,7 +34,7 @@ inline void __const_udelay(unsigned long
xloops *= 4;
__asm__("mull %0"
:"=d" (xloops), "=&a" (d0)
- :"1" (xloops),"0" (current_cpu_data.loops_per_jiffy *
(HZ/4)));
+ :"1" (xloops),"0" (boot_cpu_data.loops_per_jiffy * (HZ/4)));
__delay(++xloops);
}

for both x86 and x86_64. And it's wrong. It assumes loops_per_jiffy being
consistent on all CPUs. There _are_ asymetric multiprocessor systems out
there, and some SMP systems can become asymetric as soon as
frequency scaling is enabled. Using boot_cpu_data's loops_per_jiffy instead
of current_cpu_data's loops_per_jiffy causes delays being too short or too
long. So please drop this change.

Thanks,
Dominik
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