Inter-Core Communication Mechanisms for Microkernel Operating System based on Signal Transmission and Shared Memory

With the coming of the Internet of things(IoT) era and the development of semiconductor equipment, multicore processors have begun to be widely used in IoT devices to meet their requirements for powerful processing capabilities. Unlike desktop or server operating systems such as Linux, current embedded operating systems often do not support multi-core processors well. Tasks on different cores often require information exchange, known as inter-core communication, which significantly impacts the processing performance of multi-core operation systems. In this paper, we proposed an inter-core communication method based on signal transmission and shared memory, which is flexible and various types of data can be transferred efficiently. We have implemented and experimented with it on our own microkernel operating system named Mginkgo. The experimental results show that the average time to trigger an inter-core interrupt is about 0.093 microseconds. The average inter-core interrupt processing time is about 3.986 microseconds. And the communication time of the system for multi-core Inter-Process Communication(IPC) is about 18us, which is the same as that of single-core IPC. The inter-core communication method proposed in this paper achieves very low latency with almost no performance consumption and maintains the high performance of the whole system.