2015/11/08 by June Andronick, Corey Lewis, Carroll Morgan
Computer Science · Engineering · #Computer science #Concurrency #Concurrency control #Concurrent object-oriented programming #Context switch #Database transaction #Distributed systems and fault tolerance #Embedded system #Engineering #HOL #Interleaving #Operating system #Parallel Computing and Optimization Techniques #Programming language #Programming paradigm #Real-Time Systems Scheduling #Scheduling (production processes) #Semaphore #Uniprocessor system #cs.LO #cs.OS
paper · pdf · doi:10.4204/eptcs.196.2
published as EPTCS 196, 2015, pp. 10-24 · In Proceedings MARS 2015, arXiv:1511.02528
openalex publication_date 2015/11/08 · arxiv created 2015/11/13 · arxiv updated 2015/11/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We introduce a controlled concurrency framework, derived from the Owicki-Gries method, for describing a hardware interface in detail sufficient to support the modelling and verification of small, embedded operating systems (OS's) whose run-time responsiveness is paramount. Such real-time systems run with interrupts mostly enabled, including during scheduling. That differs from many other successfully modelled and verified OS's that typically reduce the complexity of concurrency by running on uniprocessor platforms and by switching interrupts off as much as possible. Our framework builds on the traditional Owicki-Gries method, for its fine-grained concurrency is needed for high-performance system code. We adapt it to support explicit concurrency control, by providing a simple, faithful representation of the hardware interface that allows software to control the degree of interleaving between user code, OS code, interrupt handlers and a scheduler that controls context switching. We then apply this framework to model the interleaving behavior of the eChronos OS, a preemptible real-time OS for embedded micro-controllers. We discuss the accuracy and usability of our approach when instantiated to model the eChronos OS. Both our framework and the eChronos model are formalised in the Isabelle/HOL theorem prover, taking advantage of the high level of automation in modern reasoning tools.