星载操作系统中面向混合多任务类型的两级准入控制策略  

A Two-Level Admission Control Strategy for Mixed Sets of Real-Time Tasks in Spaceborne Operating System

作　　者：宋程昊 乔磊[1] 杨茂林 刘洪标 姜菁菁 陈熙 SONG Chenghao;QIAO Lei;YANG Maolin;LIU Hongbiao;JIANG Jingjing;CHEN Xi(Beijing Institute of Control Engineering,Beijing 100094,China;University of Electronic Science and Technology of China,Chengdu 611731,China)

机构地区：[1]北京控制工程研究所,北京100094 [2]电子科技大学,成都611731

出　　处：《空间控制技术与应用》2024年第2期93-104,共12页Aerospace Control and Application

基　　金：国家自然科学基金资助项目(62032004)。

摘　　要：随着空间技术的发展,星载操作系统从单一任务类型的封闭式系统转变为多种任务类型混合的开放式系统,此时系统的可预测性难度和不确定性增大,而现有的表调度策略已无法解决该场景下多任务类型混合调度时的可调度性分析问题,同时也不能支持系统运行时新任务的动态载入,阻碍了星载操作系统的智能化和多样化发展.针对该问题,本文以保障航天器的实时性需求及功能的可扩展性为研究目标,提出基于任务关键等级的两级准入控制策略.通过模型建立对任务的时间特性进行了描述,并全面分析了高优先级任务产生的最大干扰时间,进而分别提出基于干扰时间上界和基于响应时间分析的可调度性判定方法.实验结果表明,相较于现有算法,本文方法极大地减小了高优先级任务干扰时间的计算开销,并通过对任务运行时信息的追踪,改善了算法实时性能,提升了处理器利用率,为解决航天器系统中零散任务的准入控制问题提供了理论基础.With the development of space technology,the transformation of spaceborne operating system from a closed system with a single task type to an open system with mixed sets of tasks increases the difficulty of predictability and uncertainty of system.The existing table-based scheduling strategy is no longer applicable and can’t solve the schedulability analysis problem of mixed sets of tasks in this scenario.At the same time,this method can’t support the dynamic loading of new tasks during system operation,hindering the intelligent and diversified development of onboard operating systems.In response to this issue,this paper,aiming to ensure the real-time requirements and scalability of spacecraft functions,proposes a two-level admission control strategy based on task’s critical level.The real-time characteristics of tasks are described through model establishment,and the maximum interference generated by tasks with higher priority is comprehensively analyzed.Then,schedulability determination methods based on Interference Bound Function and Response Time Analysis are proposed.Experimental results show that compared to the existing algorithm,our method greatly reduces the cost of computing interference from tasks with higher priority;By tracking the runtime information of tasks,both schedulability determination methods improve real-time performance of algorithms and increase processor utilization,hence providing a theoretical basis for solving the admission control problem of aperiodic tasks in spacecraft systems.

关 键 词：星载操作系统 混合实时任务 准入控制 可调度性判定 

分 类 号：V44[航空宇航科学与技术—飞行器设计] TP273[自动化与计算机技术—检测技术与自动化装置]