Linux内核的实时支持的研究与实现

RESEARCH AND IMPLEMENTING OF REAL-TIME SUPPORT OF LINUX KERNEL

目前嵌入式计算的发展对实时多任务操作系统（ＲＴＯＳ）的需求日益迫切，而Ｌｉｎｕｘ内核的实时支持研究为迎合这种需求提供了新的可能性．通过从中断控制、实时调度策略、内核抢占机制及细粒度定时器几方面深入研究与实现了Ｌｉｎｕｘ内核的实时支持，以使之成为一个较为完善的ＲＴＯＳ．通过把实时部分设计为可配置单元，以保留Ｌｉｎｕｘ原有系统支持及ＡＰＩ．另外，为扩展系统适用范围，提出了可支持多实时调度策略的二阶段调度方案，同时指出了当前方案的不足和今后的研究方向．

The demand for real-time operating system (RTOS) is becoming more and more urgent because of the development of embedded computing. The new possibility is offered to meet this demand by the research of real-time support of Linux kernel. In order to make Linux a perfect RTOS, the real-time support of Linux kernel is studied and implemented through four aspects: interrupt control, real-time scheduling policy, kernel preemption and high resolution timer. In order to keep the original system function and API of Linux, the real-time part is designed into a configurable unit. The method of two phases scheduling is discussed and its aim is to support real-time scheduling policies as more as possible and extend the system＇s applicable range. At the same time, the shortcoming of the present scheme is pointed out and the development direction in the future is discussed.