The current implementation of per_cpu relies on several non-c99 features,
and in additional involves arbitrary pointer arithmetic which is not MIS-
RA C friendly.
This patch introduces struct per_cpu_region which holds all the per_cpu
variables. Allocation of per_cpu data regions and access to per_cpu vari-
ables are greatly simplified, at the cost of making all per_cpu varaibl-
es accessible in files.
Signed-off-by: Huihuang Shi <huihuang.shi@intel.com>
