The Research And Practice Of Real-Time Performance Of Linux Kernel

For domestic shortcomings in RTOS development, the paper did comprehensive research on it, especially on its real-time performance. By introducing many effective approaches, an RTOS kernel with hard real-time performance was built.Considering preemptive priority-based scheduling method of RTOS, we brought forward an improved multi-priority ready queue algorithm. With O(1) time complexity, the algorithm ensures the stability and real-time performance of scheduling. We proposed a configurable multi-resolution timer mechanism. Based on the timer resolution configured by user itself, the kernel adopts a double-resolution timer mechanism, which distinguishes normal timer interrupt and high-resolution timer interrupt in complete. With this mechanism, which can reduce the unnecessary cost with strong real-time performance, we resolved the contradiction between real-time performance and system efficiency. Based on the conception of centralized management, the paper handled external interrupts according to the processor features. Besides, double stack mechanism was also applied in the kernel, with which the problem of stack overflow caused by interrupt nesting was resolved efficiently.The paper developed a hard real-time operating system kernel. We hope that our work could have some impetus to domestic development of RTOS.