Method for detecting task endless loop in operating system and operating system

Abstract

The invention provides a more comprehensive method for detecting task endless loop in an operating system and an operating system for realizing the method. Different from the existing endless loop detection method which compares the continuous running time of a task with a threshold value to judge whether an endless loop exists, the method of the invention compares the accumulated length of time of ready mode with a threshold value to judge whether an endless loop exists. The invention is based on the theory that in the priority-based preemptive operating system, when a task performs an endless loop and does not quit the CPU actively, the task is always in the ready mode in any conditions. By counting the accumulated length of time of the ready mode of one task to judge the endless loop, the omission of the endless loop which quits the CPU passively can be avoided.

Description

technical field [0001] The invention relates to a computer operating system, in particular to an infinite loop detection technology in an operating system based on task priority preemption. Background technique [0002] In the operating system based on the task priority scheduling policy, when the high priority task is in the ready state, the low priority task must not be scheduled. In general, high-priority tasks will not run all the time, and task designers will actively or passively give up CPU execution so that low-priority tasks can be executed. The form of a task voluntarily giving up the CPU is generally: delaying its own execution, waiting for a period of time before resuming execution; or blocking itself because it is waiting for a certain event. The passive form is mainly: the task is preempted by a higher priority task. When a high-priority task causes an infinite loop due to design or coding errors, and the code in the infinite loop does not actively give up th...

AI Technical Summary

Problems solved by technology

When the detected task does not run continuously but intermittently, although the task may already be in an endless loop state, it will still temporarily give up the CPU passively

For example, a task has an infinite loop, but because there are higher priority tasks, the infinite loop task will still temporarily stop. At this time, the existing infinite loop detection method has temporarily given up the control of the CPU due to the infinite loop task. The running time of the task is cleared, and the infinite loop is missed

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