Optimized Implementation of Multirate Mixed-Criticality Synchronous Reactive Models

Abstract

Model-based design using Synchronous Reactive (SR) models enables early design and verification of application functionality in a platform-independent manner, and the implementation on the target platform should guarantee the preservation of application semantic properties. Mixed-Criticality Scheduling (MCS) is an effective approach to addressing diverse certification requirements of safety-critical systems that integrate multiple subsystems with different levels of criticality. This article considers fixed-priority scheduling of mixed-criticality SR models, and considers two scheduling approaches: Adaptive MCS and Elastic MCS. We formulate the optimization problem of minimizing the total system cost of added functional delays in the implementation while guaranteeing schedulability, and present an optimal algorithm based on branch-and-bound search, and an efficient heuristic algorithm.