Youquan, As far as I know both the
sched_smt_power_savings/sched_mc_power_savings are broken for atleast an
year.

Have you checked the state of 'sched_mc_power_savings' to see if it is
working or gets addressed with your proposed patches?

Thanks Suresh!

We have verified that sched_mc_power_savings works well in mainline and
-tip tree, only sched_smt_power_savings broken.

Sorry. My proposed patch last night still need be refreshed. After I closely look
at SD_PREFER_SIBLING logic, there is possible a fighting which Peter has
mentioned it.

I will post a update patch soon.

-Youquan