Response-time analysis of arbitrarily activated tasks in multiprocessor systems with shared resources

As multiprocessor systems are increasingly used in real-time environments, scheduling and synchronization analysis of these platforms receive growing attention. However, most known schedulability tests lack a general applicability. Common constraints are a periodic or sporadic task activation pattern, with deadlines no larger than the period, or no support for shared resource arbitration, which is frequently required for embedded systems. In this paper, we address these constraints and present a general analysis which allows the calculation of response times for fixed priority task sets with arbitrary activations and deadlines in a partitioned multiprocessor system with shared resources. Furthermore, we derive an improved bound on the blocking time in this setup for the case where the shared resources are protected according to the Multiprocessor Priority Ceiling Protocol (MPCP).