Abstract
Assume that a real-time programP T consisting of a number of parallel processes is executed on a system having a setPr of processors which are shared between the processes by a real-time schedulerS T. Assume that PT must meet some timing deadlines. We show that such an implementation ofP T can be represented as a transformationL(P T) and that the deadlines ofP T will be met if they are satisfied by the timing properties of the transformed program. The condition for feasibility of a real-time program executed under a scheduler is formalized and rules are provided for verification. The schedulerS T can be specifiedgenerically and applied to different programs, making it unnecessary to introduce low-level operations such as scheduling primitives into the programming language. Thus real-time program specification and Schedulability can be considered in the same framework and the timing properties of a program can be determined at the specification level. By separating the specification of the scheduler from that of the program, the feasibility of an implementation can be proved by considering a scheduling policy rather than its implementation details.
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Liu, Z., Joseph, M. & Janowski, T. Verification of schedulability for real-time programs. Formal Aspects of Computing 7, 510–532 (1995). https://doi.org/10.1007/BF01211630
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DOI: https://doi.org/10.1007/BF01211630