Cyber Physical Systems are composed of many embedded systems which monitor and control the physical processes for tight integrations of computation and physical processes. Such embedded systems require not only real-time capabilities but also high throughput and low power consumption. High throughput is mainly achieved by parallel architectures such as Simultaneous Multithreading (SMT) and Chip Multiprocessor (CMP), and low power consumption is mainly achieved by Real-Time Dynamic Voltage and Frequency Scaling (RT-DVFS) under the real-time constraint. In this paper, we present a RT-DVFS algorithm called Hetero Efficiency to Logical Processor (HeLP) which can reduce power consumption easily and effectively in prioritized SMT processors. We also present Hetero Efficiency to Logical Processor with Temporal Migration (HeLP-TM) which applies the temporal migration technique to HeLP. Simulation results show that HeLP can reduce power consumption effectively and HeLPTM is more effective than HeLP.