CPU on-line testing method based on grey box

Abstract

The invention discloses a CPU on-line testing method based on a grey box. The method includes the following steps that a safe computer language code rule is set; a minimum language subset related to CPU functions is extracted; a CPU functional test case is generated; an object code is generated; the object code operates on a tested CPU, and a test result is produced; results are compared on another CPU; an expected result is stored on another CPU; whether the test result is identical with the expected result or not is judged; if the test result is identical with the expected result, CPU functions are judged as normal, and operation continues; if the test result is not identical with the expected result, system failure processing is judged. Advanced computer languages are utilized to achieve on-line testing on the CPU functions, transportability and readability of a test code are improved, a CPU functional layer, truly used commands and complete coverage of a register are considered, a CPU does not need to be shut off or interrupted, preservation and recovery of the internal state of the CPU before and after self-testing are not needed, and the current state of the CPU cannot be damaged.

Description

Technical field [0001] The invention belongs to the field of software algorithms and is used for online detection of the correctness of CPU execution functions. Background technique [0002] In industrial control systems and safety signal systems (used in avionics, railway signaling, nuclear power and other industries), the central processing unit CPU has established the core control position, which plays an extremely important role in ensuring the safety and reliability of the system. In order to ensure that the CPU can perform functional tasks correctly, the CPU must be monitored periodically. When an abnormality is discovered, the fault management mechanism shall be activated, and safety measures shall be taken in time to avoid more serious accidents. In the security field, CPU detection has always been a difficult point in the industry. The usual practices are figure 1 Shown. [0003] The existing method is to detect the internal resources of the CPU, such as the register ban...

AI Technical Summary

Problems solved by technology

[0004] 1. Due to the increasing integration of CPUs and the increasingly complex internal structure, operations inside the CPU may bring unpredictable risks.

[0005] 2. It is often necessary to turn off interrupts for CPU testing during system operation, which affects the normal work and real-time response capabilities of the security system

[0006] 3. The test results of the CPU itself are unreliable. If the CPU itself fails, the test results need to be judged by yourself, which is unpredictable.

[0007] 4. CPU test cases are usually implemented with low-level assembly code. Due to the need to consider CPUs with different architectures, the portability is poor, and different test programs need to be written on different CPUs.

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