摘要
基于优先级抢占调度策略的实时内核,优先级反转是涉及多任务共享资源时最容易出现的现象,此现象是实时应用系统产生不可预知错误的重要因素.阐述了μC/OS-Ⅱ实时内核中优先级反转问题产生的原因和对系统实时性的影响,提出了调度器加锁及优先级置顶两种抑制μC/OS-Ⅱ优先级反转的实现方法.通过实验验证,这两种方法能够有效地抑制μC/OS-Ⅱ中的优先级反转.最后对两种实现方法的性能进行了分析、比较.
For the real-time kemel adopting preemptive priority policy, priority inversion phenomenon may occur frequently under the condition of multiple tasks share resource. Some unpredictable errors in real-time application system perhaps derive from this phenomenon. Firstly, the cause generating the priority inversion problem and its effect on the real-time performance of the system were expounded. And then, two approaches, named as scheduler lock and priority ceiling protocol, were proposed for reducing the priority inversion phenomenon in μC/OS -Ⅱ. It is experimentally verified that two proposed approaches can effectively reduce the priority inversion in μC/OS-Ⅱ. Finally, the performance of two approaches had been compared and analyzed.
出处
《沈阳工业大学学报》
EI
CAS
2007年第4期427-431,共5页
Journal of Shenyang University of Technology
基金
教育部"春晖计划"科研合作资助项目(Z2005-2-11013)
关键词
实时内核
实时系统
优先级反转
优先级继承
优先级天花板
real-time kernel
real-time system
priority inversion
priority inheritance
priority ceiling
