一种实时的嵌入式Linux调度策略

Research on a Kind of Real-time Embedded Linux Schedule

随着Linux广泛应用于嵌入式系统、实时控制等领域,增强Linux内核的实时性变得尤为重要。Linux2.6内核加入了抢占点,可以最大限度地降低内核不可抢占的时间间隔,但嵌入式系统实时性要求较高,因此基于嵌入式Linux(裁减的Linux2.6内核),分析实时调度策略,提出改进的实时调度策略IPEDF,该策略吸取了截止期最早最优先算法的优点,使内核可以在任何时间被抢占。最后对嵌入式Linux和基于IPEDF的嵌入式Linux进行测试,结果表明后者的任务响应时间少,从而进一步提高了嵌入式Linux2.6的实时性。

As Linux applying widely in the area of embedded system, real-time control, it is more important to strengthen general Linux kernel real-time capability. Preemptive points joined in Linux2.6 kernel, and that reduces extremely non-preemptive time, but embedded system requires higher real-time capability, so real-time schedule is analyzed based on embedded Linux（ reduction Linux2.6 kernel） , proposed real-time schedule IPEDF（ Improved Preempt Earliest Deadline First）, which extracted the merit of earliest deadline first algorithm, and make the kernel preemptive at any time. At last, embedded Linux and the embedded Linux based IPEDF are tested, which showed the latter has shorter task response time, and further more enhances the realtime performance of the embedded Linux.