MSRP-FT: reliable resource sharing on multiprocessor mixed-criticality systems

Driven by applications such as autonomous vehicles, spacecrafts, robotics, and industrial automation, real-time systems are required to implement ever more complex functionalities with high performance, while maintaining conventional timing predictability, reliability, and cost efficiency. Necessarily, large-scale resource sharing on multiprocessor architectures has to be deployed. Unfortunately, existing protocols that manage shared resources and bound blocking delay have not considered reliability, i.e. how to handle faults. Contention over shared resources may be seriously aggravated by re-executions that are essential to satisfy a system's reliability requirements. Hence, there exists a significant barrier to applying resource sharing in the mission-critical sector. This paper fills that gap between reliability and resource sharing. Focusing on mixed-criticality systems (MCS), which widely exist in practice and make the problem more challenging, we propose a fault-tolerance solution which includes the first fault-tolerance multiprocessor resource sharing protocol (namely MSRP-FT) and a system execution model that supports the application of MSRP-FT in MCS. Our aim is to minimize blocking time while satisfying reliability requirements. A schedulability analysis is reported which can guarantee that timing constraints are respected. Compared to the state-of-the-art method, developed for fault-tolerant MCS without resource sharing, we improve the system schedulability by an average of 1.28× in stable modes and 1.1× during the mode switch.