Schedulability Analysis Of AUTOSAR OS Schedule Table Based On Formal Model

The rapid growth in the number of electronic controller units is making automotive electronics more complex.It is a chanllenge to guarantee the reliability and safety of automotive electronics.In order to remedy this unmanageable situation,AUTOSAR(AUTomotive Open System Architecture)was proposed to establish an open and standardized software architecture.As a real-time system,the AUTOSAR OS must be subject to strict timing constraints.The design of the AUTOSAR OS must be verified to ensure that it will never violate its time constraint.The schedule table mechanism is an important character of the AUTOSAR OS.It increases the flexibility of task deployment and makes it difficult to analyze schedulability.Rigorous mathematical analysis methods are used to verify the schedulability of the AUTOSAR OS.Firstly,directed digraphs are used to model schedule tables.The schedule table model uses a path to describe the schedule's behavior in one period.By abstracting the path into workload,the time that the task is blocked and preempted in one period can be effectively analyzed.Then schedulability analysis algorithm follows the rate monotonic analysis and check whether the task can satisfy its time property.Finally,based on the directed digraphs model,a complete and effective algorithm is provided to analyze the schedulability of the AUTOSAR OS,and an AUTOSAR OS schedulability analysis tool is implemented.The model based on directed graphs provides a method for effectively analyzing the schedulability of AUTOSAR OS while properly describing the time property of the schedule table mechanism.This model strikes a balance between expressiveness and analytical efficiency.It accurately describes system design and provides effective schedulability analysis methods and tools to help developers analyze schedulability of system during the design phase of AUTOSAR OS.