Emerging real-time applications increasingly rely on multicore embedded systems, where tasks must coordinate access to shared local and global resources. Such accesses are protected by critical sections and managed by resource-sharing protocols to ensure mutual exclusion and timing predictability. However, transient faults occurring inside critical sections can corrupt execution and propagate errors across tasks, while directly com- bining conventional locking with fault-tolerance mechanisms can significantly increase blocking. Recent fault-tolerant resource- sharing approaches improve recovery through parallel replica execution, but still suffer from sequential global access and coordination overhead. In previous work, we proposed the Lock- frEe Fault-Tolerant Resource Sharing (LEFT-RS) protocol, which improves fault-tolerant global resource access by allowing con- current critical-section execution. However, LEFT-RS enforces non-preemptive global resource access, which can cause excessive arrival blocking for high-priority tasks and limit schedulability. This paper introduces the CAFT-RS (Ceiling-based Access for Fault-Tolerant Resource Sharing) protocol, which applies a priority-ceiling mechanism to both local and global resource ac- cesses. CAFT-RS allows higher-priority tasks to preempt ongoing global accesses while preserving correctness through dedicated post-preemption rules. We develop a worst-case response-time analysis that accounts for both the reduction in arrival blocking and the additional preemption overhead. Extensive evaluation results show that CAFT-RS improves schedulability by up to 188.5% on average over LEFT-RS.
CORE (COnnecting REpositories)
CORE (COnnecting REpositories)