Graded task switching method based on PowerPC processor structure

Abstract

The hierarchical task switching method based on the PowerPC processor structure belongs to the embedded real-time operating system field, and is characterized in that: it divides the user task context into basic, extended and optional three parts for the particularity of the PowerPC processor structure. Among them, according to the system configuration and task scheduling, three methods are adopted: only the basic part is pushed, the basic and extended parts are pushed into the stack, and all contexts are pushed into the stack; the interrupt handler first executes the basic part into the stack, and then judges the nature of task scheduling after executing the interrupt processing , choose to execute the next level push operation, call the scheduler, or resume the scene and return to the user task. Reduce unnecessary stack operations. As a part of Tsinghua University's automotive electronics open system, it is implemented on the MPC555 platform. Tests show that it improves the efficiency of task switching and speeds up system operation.

Description

technical field [0001] The hierarchical task switching method based on PowerPC processor structure belongs to the technical field of embedded real-time operating system, in particular to the technical field of embedded real-time operating system based on PowerPC processor structure. Background technique [0002] The task switching mechanism is the core of the multitasking real-time operating system. Among them, stack operation is the main operation of task switching. The rationality of the stack operation is directly related to the stability and operating efficiency of the operating system. The main task of the task switching mechanism is to save and restore the necessary program running scene, so that the program can be interrupted during the execution without producing wrong results. On the one hand, the real-time operating system requires a higher speed in the task switching process; on the other hand, the embedded system requires the task switching process to save reso...

AI Technical Summary

Problems solved by technology

[0006] Aiming at the problem that the task switching mechanism of the existing real-time operating system is not closely combined with the processor characteristics, there are redundant operations in the switching process, and the use of the stack is not economical, the present invention is based on the PowerPC structural instruction system stack operation instructions that can allocate stack space in batches. , a hierarchical task switching method is proposed, which mainly includes the following contents:

Images