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uxTaskGetStackHighWaterMark return type

Posted by Toan Pham on June 5, 2012

Hi, i am running freertos an a 8bit xmega processor. I am trying to find the size of the unused stack space by using call to uxTaskGetStackHighWaterMark. However, uxTaskGetStackHighWaterMark returns portBASE_TYPE which is defined as unsigned char in portmacro.h. This is not good, for example if the total unused space is more than 255, calls to uxTaskGetStackHighWaterMark is subjected to rollover, and is inaccurate.

I looked further into uxTaskGetStackHighWaterMark and it makes another call to check unused stack size, which returns unsigned short, but get casted to port_BASE_TYPE in uxTaskGetStackHighWaterMark. Would it be better if uxTaskGetStackHighWaterMark returns unsigned short instead?


RE: uxTaskGetStackHighWaterMark return type

Posted by Richard on June 5, 2012
Yes - my bad - there is a change request on exactly that point already but I have not implemented it yet. For now, it is easy enough to edit the source code so a size_t is returned instead, but long term you don't want to be editing anything in the source code (maintenance nightmare when FreeRTOS changes) so I really need to do this in the main line. Apologies for not doing so already.


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