嵌入式系统设计中的部件优先级分配算法

Component Priority Assignment in the Design of Embedded Systems

面向数据实时处理领域嵌入式系统的设计经常采用 DFG图作为系统模型 ,为了获取足够的时间性能 ,这类系统通常含有大量并发运行的软硬件部件 ,因此会出现由结构和数据相关所引起的共享资源争用现象 ,而解决这种争用的方法可以是给部件设置优先级 .针对这一问题 ,提出一种优先级分配算法 ,它能在某一个执行时间约束前提下 ,最大可能为并发运行的各部件找到一种优先级分配方法 .此外 ,通过这一算法还能获得了一种快速判定机制 ,确定一组并发运行部件在存在资源争用情况下是否能够满足某一给定的时间约束 ,因此它可同时应用于嵌入式系统软硬件协同设计中的系统设计和实现设计阶段 .

Data flow dominated embedded systems often use DFG graph as system mod el. To achieve desired performance, these systems usually contain a lot of hardw are/software components working in parallel, which results in the contention for shared resources due to architecture and data dependencies. The approach to sol ve the contention can be priority assignment. Introduced a priority a ssignment algorithm which can find out a priority assignment for a given set of components working in parallel with a given timing constraints, as long as such an assignment is possible. In addition, the algorithm also provides us a fast wa y to calculate, whether a set of components working in parallel can guarantee a given timing constraint. Hence the algorithm can be applied both in system desig ning phase and implementation designing phase of hardware/software co-design fo r embedded systems.