[tesla-dev] [PATCH] for bug: C-state statistics seem a bit off

[Eric Saxe]

Li, Aubrey wrote:
> err..., firstly, how about the clock CPU or uniprocessor system?
>   
Yes, for the clock CPU / uniprocessor system, I wouldn't expect the gap 
to be very long (right now).

> do you want to calculate the gap or not?
>   
My thought is yes...although as you point out in some cases that gap 
won't be very large, but looking ahead that might not be the case.

> And, for other CPUs, how do you read their kstat from clock CPU?
>   
You can read any CPUs kstats from any CPU. The act of reading the CPU 
triggers the internal kstat update routine, which reads the state for 
the given CPU from someplace where it's been stashed (such as it's CPU 
structure). All that can be done without waking the sleeping CPU.

Thanks,
-Eric