MATLAB: Do I get an error when setting ‘canBeInvokedConcurrently’ to true

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I received the following error when generating code for AUTOSAR and set the 'cenBeInvokedConcurrently' to be true.

Simulink Function block 'myBlock' may not be invoked concurrently because one of the outputs of block 'myBlock/mySubBlock' is global data. This diagnostic is reported because 'canBeInvokedConcurrently' option is selected on the AUTOSAR runnable mapped to this Simulink Function. You may investigate further by deselecting that option, and examining the generated code.

Component:Simulink | Category:Block diagram error

Best Answer

The outputs are global variables because of the "Data Type Conversion" block within the "myBlock/mySubBlock" block. The "Data Type Conversion" block generates a global, and thus, the function cannot be reentrant (which is required for concurrent access).

If you want to allow for concurrency, remove the "Data Type Conversion" block and specify the output type directly within the "Out1" block:

1) Double click the "Out1" block. A dialog will appear.

2) Within the dialog, go to the Signal Attributes tab.

3) You can specify the data type in there.

Related Solutions

MATLAB: How can we ensure that the Outport function call in the generated code is present in a conditionally executed statement when merging ouputs from two runnables in Simulink R2016b

This can be done by setting all the outports starting from the 'If Action SubSystems' to the 'Merge' block as virtual. This can be done in the following manner -

1. Starting from the '/Runnable2_subsystem/ExplicitWrite/If Action Subsystem', double click on the 'Out1' outport block and check the 'Ensure outport is virtual' option in the 'Main' tab.

2. Following along this signals path, set the '/Runnable2_subsystem/Subtracter' outport as virtual using the above procedure.

3. Similarly starting from the 'Out1' outport in the '/Runnable3_subsystem/ExplicitWrite/If Action Subsystem' we set the outports along the other signal to the merge block as virtual.

4. We also set the '/Runnable3_subsystem/Multiplier' outport as virtual.

Please find the attached updated Simulink model ("autosar_multirunnables_virtual_outports.slx"). If we generate the code for this model, we can see that the *Rte_IWrite** function calls are present within conditional statements as follows -

The call corresponding to the Runnable2 write -

161  if (rtDWork.Output_DSTATE_d >= rtb_Subtract) {
162    /* Outputs for IfAction SubSystem: '<S6>/If Action Subsystem' incorporates:
163     *  ActionPort: '<S9>/Action Port'
164     */
165    /* Outport: '<Root>/PPort_DE4' incorporates:
166     *  DataTypeConversion: '<S2>/Data Type Conversion'
167     *  Inport: '<S9>/In1'
168     */
169    Rte_IWrite_Runnable2_PPort_DE4(rtDWork.Output_DSTATE_d);
170
171    /* End of Outputs for SubSystem: '<S6>/If Action Subsystem' */
172  }

The call corresponding to the Runnable3 write -

236  if (rtDWork.Output_DSTATE >= rtb_TmpSignalConversionAtIn1Out * tmp[0]) {
237    /* Outputs for IfAction SubSystem: '<S11>/If Action Subsystem' incorporates:
238     *  ActionPort: '<S14>/Action Port'
239     */
240    /* Outport: '<Root>/PPort_DE4' incorporates:
241     *  DataTypeConversion: '<S3>/Data Type Conversion'
242     *  Inport: '<S14>/In1'
243     */
244    Rte_IWrite_Runnable3_PPort_DE4(rtDWork.Output_DSTATE);
245
246    /* End of Outputs for SubSystem: '<S11>/If Action Subsystem' */
247  }

Please note that the checkbox option ('Ensure outport is virtual') in the 'Outport' block was introduced in Simulink R2016b. Therefore, this workaround can be used to generate code as shown above from Simulink version R2016b.

MATLAB: Can I eliminate the extra copy of a variable that is created in the generated code when using a “MATLAB function” block with a “Data Store Read” block as the input

To generate code without an extra copy of the variable, you will have to change some settings. Here are the steps to follow:

1) Open the "Ports and Data Manager" as follows: Double click the "MATLAB function" block to open the function in MATLAB. In the top toolbar, select "Edit Data" found in the "Simulink" section.

2) In the "Ports and Data Manager" dialog window, change myDataStore to be a Data Store instead of an input to the MATLAB function block.

3) Declare myDataStore as a global inside the MATLAB function as follows:

>> global myDataStore;

4) Wrap myDataStore inside a call to coder.ref:

>> coder.ceval('-global','myCFunction', coder.ref(myDataStore));

You can refer to the following documentation page for more information about "coder.ref":

https://www.mathworks.com/help/releases/R2017b/coder/ref/coder.ref.html

5) Comment out the "Data Store Memory Read" block that is currently connected to the "MATLAB function" block.

6) Double click the "Data Store Memory" block and go to the signal attributes tab. The signal type cannot be set to "auto". Change it accordingly. For example:

7) Now you can generate code without the extra copy of the variable.

Best Answer

Related Solutions

MATLAB: How can we ensure that the Outport function call in the generated code is present in a conditionally executed statement when merging ouputs from two runnables in Simulink R2016b

MATLAB: Can I eliminate the extra copy of a variable that is created in the generated code when using a “MATLAB function” block with a “Data Store Read” block as the input

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