Schedulability analysis and task mapping for real-time on-chip communication

Abstract

Priority-based wormhole switching with a priority share policy has been proposed as a possible solution for real-time on-chip communication. However, the blocking introduced by priority share complicates the analysis process. In this paper, we propose a new "per-priority" basis analysis scheme which computes the total time window at each priority level instead of each traffic-flow. By checking the release instance of each flow at the corresponding priority window, we can determine schedulability efficiently. Building on this static analysis, for a given set of tasks and network topology, we further propose a task mapping and priority assignment algorithm, in such a way that the hard time bounds are met with a reduced hardware overhead. Experiment results show that significant resource saving can be achieved with no performance degradation in terms of missed deadlines. By using this approach, a broad class of real-time communications with different QoS requirements can be explored and developed in a SoC/NoC communication platform.