Real-Time Supervisory Control of a Processor for Non-Preemptive Execution of Periodic Tasks

In this article, a method for scheduling a processor for non-preemptive execution of periodic tasks is presented. This method is based on the formal framework of supervisory control of timed discrete-event systems. It is shown that, with this method, the problem of determining schedulability and the problem of finding a scheduling algorithm are dual since a solution to the former necessarily implies a solution to the latter and vice versa. Furthermore, the solution to the latter thus obtained is complete in the sense that it contains all “safe” sequences of task execution with the guarantee that no deadline is missed. Examples are described to illustrate this method. Implication of the results and computational complexity associated with this method are discussed.