Created by: luotao1

There are several global variables and functions： https://github.com/PaddlePaddle/Paddle/blob/fe32879d2abf9efeb2839eba27e8a419852635fc/paddle/fluid/platform/device_context.h#L380-L399 Could they move into MKLDNNDeviceContext class? @jczaja @LeoZhao-Intel