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Details of old bug fix for change of priority

Posted by Bernhard on November 3, 2010
I'm stuck with version 3.2.0 of FreeRTOS in some ancient code and updating to a newer version is not really an option, unfortunately. My platform is an ARM7 controller (STR710). The compiler tool chain I use is YAGARTO.

I would like to use the feature vTaskPrioritySet() when evolving the code but found a notice in the http://www.freertos.org/History.txt for the change from version 4.0.4 to version 4.0.5:

“Bug fix: The 'value' of the event list item is updated when the priority of a task is changed. Previously only the priority of the TCB itself was changed.”

Can anyone help me with the following questions:

  1. Does this fix affect a bug that was present in version 3.2.0 already?[/il]
  2. If so, are there any details on this issue still available (old ticket or such)? What would the effect of that bug be?[/il]

Thank you for all and any help,

RE: Details of old bug fix for change of priority

Posted by Richard on November 3, 2010
Wow, that is going back a long way. From the sound of the description the problem would have been that after calling vTaskPrioritySet( task_id, new_priority ) the task associated with task_id would only have changed to new_priority the next time it executed. In other words, when the scheduler was making a decision as to which task to execute next the decision would have been made as if task_id had its original priority, but once it had been selected from that point on the decision would be made as if it had its new priority.


RE: Details of old bug fix for change of priority

Posted by Bernhard on November 8, 2010
Thank you very much for the help.


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