METHOD OF DATA EXCHANGE BETWEEN A PRIMARY CORE AND A SECONDARY CORE IN A REAL-TIME OPERATING SYSTEM

• US 20180165127A1
• Filed: 12/13/2016
• Published: 06/14/2018
• Est. Priority Date: 12/13/2016
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Lee, Young Joo, Berry, Daniel J., Welchko, Brian A.
• Granted Patent: US 10,162,680 B2
• Time in Patent Office: Days
• CPC Class Codes: B60K 6/26 characterised by the motors or the generators
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: G05B 15/02 electric
• CPC Class Codes: G06F 15/17325 Synchronisation; Hardware support therefor intertask synchronisation G06F9/52
• CPC Class Codes: G06F 9/485 Task life-cycle, e.g. stopping, restarting, resuming execution G06F9/4881 takes precedence
• CPC Class Codes: G06F 9/505 considering the load

Abstract

A method of exchanging data in a real-time operating system, between a primary core and a secondary core in a multi-core processor, includes executing a primary path via the primary core and executing a secondary path via the secondary core. The primary path is configured to be a relatively faster processing task and the secondary path is configured to be a relatively slower processing task. The method includes devising a freeze in process flag to have a respective flag status set and cleared by the primary path. The method includes devising a data frozen flag to have a respective flag status set and cleared by both the primary and the secondary paths. A component that is operatively connected to the multi-core processor may be controlled based at least partially on a difference between primary and secondary sets of calculations executed by the primary and secondary cores, respectively.

Claims

1. A method of exchanging data in a real-time operating system between a primary core and a secondary core in a multi-core processor, the multi-core processor being operatively connected to a component, the method comprising:

executing a primary path via the primary core and executing a secondary path via the secondary core;

wherein the primary path is configured to be a relatively faster processing task and the secondary path is configured to be a relatively slower processing task;

devising a freeze in process flag to have a respective status set and cleared by the primary path;

devising a data frozen flag to have a respective status set and cleared by both the primary and the secondary paths; and

controlling the component based at least partially on a difference between a primary set of calculations executed by the primary core and a secondary set of calculations executed by the secondary core.

2. The method of claim 1, further comprising:

determining, via the secondary path, if the difference between the primary set of calculations executed by the primary core and the secondary set of calculations executed by the secondary core is at or below a threshold;

adjusting the component if the difference is at or below the threshold.

3. The method of claim 2, further comprising:

determining, via the primary path, if an input data should be frozen based at least partially on the respective status of the data frozen flag and the freeze in process flag;

performing, via the primary path, a primary set of calculations on the input data to obtain an output data;

performing, via the secondary path, the secondary set of calculations on the input data based at least partially on the respective status of the data frozen flag; and

wherein the secondary path requires a transfer of the input data from the primary core to the secondary core to perform the secondary set of calculations.

4. The method of claim 3, further comprising:

preventing the input data from being used in the secondary set of calculations, via the freeze in process flag and the data frozen flag, if the secondary path is executed during a period of time between said determining if the input data should be frozen and said performing the primary set of calculations.

5. The method of claim 4, wherein said determining if the input data should be frozen based at least partially on the respective status of the data frozen flag and the freeze in process flag includes:

if the respective status of both the data frozen flag and the freeze in process flag are false, then freezing the input data and setting the respective status of the freeze in process flag as true, via the primary core;

transferring the frozen input data from the primary core to the secondary core; and

if the respective status of the data frozen flag is not false, and the freeze in process flag is true, then setting the respective status of both the freeze in process flag and the data frozen flag as false, via the primary core.

6. The method of claim 4, further comprising:

determining, via the primary path, if the output data is valid for comparison with the secondary set of calculations based at least partially on the respective flag status of the data frozen flag and the freeze in process flag.

7. The method of claim 4, wherein said determining if the output data is valid for comparison includes:

if the respective status of the data frozen flag is false and the freeze in process flag is true, then freezing the output data and setting the respective status of the data frozen flag as true and the freeze in process flag as false, via the primary core;

transferring the frozen output data from the primary core to the secondary core; and

if the respective status of both the freeze in process flag and the data frozen flag are true, then setting the respective status of both the freeze in process flag and the data frozen flag as false, via the primary core.

8. The method of claim 4, wherein said performing the secondary set of calculations on the input data based at least partially on the respective status of the data frozen flag includes:

if the respective status of the data frozen flag is true, performing the secondary set of calculations on the frozen input data, via the secondary core.

9. The method of claim 8, further comprising:

setting the respective status of the data frozen flag as false, via the secondary core, after performing the secondary set of calculations.

10. A system comprising:

a controller having a processer with at least two execution units, including a primary core and a secondary core configured to execute a primary path and a secondary path, respectively;

wherein the primary path is configured to be a relatively faster processing task and the secondary path is configured to be a relatively slower processing task;

a component operatively connected to the controller;

wherein the controller includes a tangible, non-transitory memory on which is recorded instructions for executing a method for exchanging data between the primary core and the secondary core;

wherein execution of the instructions by the processor causes the controller to;

devise a freeze in process flag to have a respective status set and cleared by the primary path;

devise a data frozen flag to have a respective status set and cleared by both the primary and the secondary paths; and

control the component based at least partially on the respective status of the data frozen flag and the freeze in process flag.

11. The system of claim 10, wherein the controller is programmed to:

determine, via the secondary path, if a difference between a primary set of calculations executed by the primary core and a secondary set of calculations executed by the secondary core is at or below a threshold; and

adjust the component if the difference is at or below the threshold.

12. The system of claim 11, wherein the controller is programmed to:

determine, via the primary path, if an input data should be frozen based at least partially on the respective status of the data frozen flag and the freeze in process flag;

perform, via the primary path, a primary set of calculations on the input data to obtain an output data;

perform, via the secondary path, the secondary set of calculations on the input data based at least partially on the respective status of the data frozen flag; and

wherein the secondary path requires a transfer of the input data from the primary core to the secondary core to perform the secondary set of calculations.

13. The system of claim 12, wherein the controller is programmed to:

prevent the input data from being used in the secondary set of calculations, via the freeze in process flag and the data frozen flag, if the secondary path is executed during a period of time between said determining if the input data should be frozen and said performing the primary set of calculations.

14. The system of claim 13, wherein said determining if the input data should be frozen based at least partially on the respective status of the data frozen flag and the freeze in process flag includes:

if the respective status of both the data frozen flag and the freeze in process flag are false, then freezing the input data and setting the respective status of the freeze in process flag as true, via the primary core;

transferring the frozen input data from the primary core to the secondary core; and

if the respective status of the data frozen flag is not false, and the freeze in process flag is true, then setting the respective status of both the freeze in process flag and the data frozen flag as false, via the primary core.

15. A method of monitoring torque in a traction system having a multi-core processor and a component, the multi-core processor having a primary core and a secondary core, the method comprising:

executing a primary path via the primary core, the primary path including a primary set of calculations for obtaining an original set of torque values;

executing a secondary path via the secondary core, the secondary path including a secondary set of calculations for obtaining a redundant set of torque values;

wherein the primary path is configured to be a relatively faster processing task and the secondary path is configured to be a relatively slower processing task;

devising a freeze in process flag to have a respective status set and cleared by the primary path;

devising a data frozen flag to have a respective status set and cleared by both the primary and the secondary paths;

determining if a difference between the primary set of calculations and the secondary set of calculations is at or below a threshold; and

adjusting the component if the difference is at or below the threshold.

16. The method of claim 15, further comprising:

determining, via the primary path, if an input data should be frozen based at least partially on the respective status of the data frozen flag and the freeze in process flag;

performing, via the primary path, the primary set of calculations on the input data to obtain an output data;

performing, via the secondary path, the secondary set of calculations on the input data based at least partially on the respective status of the data frozen flag; and

wherein the secondary path requires a transfer of the input data from the primary core to the secondary core to perform the secondary set of calculations.

17. The method of claim 16, further comprising:

preventing the input data from being used in the secondary set of calculations, via the freeze in process flag and the data frozen flag, if the secondary path is executed during a period of time between said determining if the input data should be frozen and said performing the primary set of calculations.

18. The method of claim 16, wherein said determining if the input data should be frozen based at least partially on the respective status of the data frozen flag and the freeze in process flag includes:

if the respective status of both the data frozen flag and the freeze in process flag are false, then freezing the input data and setting the respective status of the freeze in process flag as true, via the primary core;

transferring the frozen input data from the primary core to the secondary core; and

if the respective status of the data frozen flag is not false, and the freeze in process flag is true, then setting the respective status of both the freeze in process flag and the data frozen flag as false, via the primary core.

19. The method of claim 18, further comprising:

determining, via the primary path, if the output data is valid for comparison with the secondary set of calculations based at least partially on the respective flag status of the data frozen flag and the freeze in process flag, including;

if the respective status of the data frozen flag is false and the freeze in process flag is true, then freezing the output data and setting the respective status of the data frozen flag as true and the freeze in process flag as false, via the primary core;

transferring the frozen output data from the primary core to the secondary core; and

if the respective status of both the freeze in process flag and the data frozen flag are true, then setting the respective status of both the freeze in process flag and the data frozen flag as false, via the primary core.

20. The method of claim 16, further comprising:

setting the respective status of the data frozen flag as false, via the secondary core, after performing the secondary set of calculations; and

wherein said performing the secondary set of calculations on the input data based at least partially on the respective status of the data frozen flag includes, if the respective status of the data frozen flag is true, performing the secondary set of calculations on the frozen input data, via the secondary core.