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为解决嵌入式高可信软件架构中的实时调度问题,分析了现有采用分区机制的安全系统中分区调度的不足,提出了一种基于固定周期分区的静态调度模型,并采用优先级位图算法建立了两级调度机制.为了保障分区中任务的实时性和正确性,对分区中任务采用静态优先级和最早时限优先调度(EDF)动态优先级两种调度策略,分别就其任务调度条件和可调度性进行了理论研究,针对复杂的动态优先级任务提出了一种可调度条件,并通过仿真实验进一步验证了此调度条件的正确性.“,”To address the scheduling problem in high-assurance software architecture for embedded systems, this article analyzes the limitation of partition scheduling methods of existing security systems and presents a static scheduling model based on period partition. By means of this model a two-level scheduling mechanism is constructed with priority bitmap algorithm. This article introduces two scheduling policies for tasks in partitions: fixed priority and dynamic priority based on the earliest deadline first (EDF) scheduling algorithm. The scheduling conditions and schedulability of tasks are studied, and the schedulable conditions of dynamic priority tasks are proposed. The accuracy of the scheduling conditions in this article is verified through a simulation experiment.