Research and realization of the mechanism of embedded linux kernel semaphore

Linux kernel semaphore mechanism is an effective means of synchronizing tasks which compete against each other to enter the same kernel critical section. However, the problem of priority inversion in Linux kernel semaphore is still unsolved. It is very important to solve the problem of priority inversion by means of priority inheritance when applying Linux in real-time embedded system. Based on the analysis of the Linux source codes about kernel semaphore operation, this paper realizes the base priority inheritance protocol by modifying the Linux kernel.