Relocatable Hardware Threads in Run-Time Reconfigurable Systems

Run-time reconfiguration provides an opportunity to increase performance, reduce cost and improve energy efficiency in FPGA-based systems. However, run-time reconfigurable systems are more complex to implement than static only systems. This increases time to market, and introduces run-time overhead into the system. Our research aims to raise the abstraction level to develop run-time reconfigurable systems. We present operating system extensions which enable seamless integration of run-time reconfigurable hardware threads into applications. To improve resource utilization, the hardware threads are placed on a fine granularity tile grid. We take advantage of a relocatable module placer targeting modern field programmable gate arrays (FPGAs) to manage the reconfigurable area. The module placer accurately models the FPGA resources to compute feasible placement locations for the hardware threads at runtime. Finally, we evaluate our work by means of a case study that consists of a synthetic application to validate the functionality and performance of the implementation. The results show a reduction in reconfiguration time of up to 42% and more than double resource utilization.