RE: NDArrayPool:reserve ERROR, reference count = 0, should be = 1

["Daykin, Evan via Tech-talk" <tech-talk at aps.anl.gov>]

Hm… I am not explicitly calling release() anywhere. This is my processCallbacks function-  everything else in my plugin, AFAIK, doesn’t access any shared resources.

 

void NDPluginTemperature::processCallbacks(NDArray *pArray){

    static const char *functionName = "processCallbacks";

    NDArrayInfo_t arrayInfo;

    if(pArray->dataType != NDUInt16){

        asynPrint(this->pasynUserSelf, ASYN_TRACE_ERROR,

        "%s:%s: Only UInt16 supported.", driverName, functionName);

        return;

    }

    std::string lastCalFileName = this->calibrationFileName;

    getStringParam(this->calibrationFileNameIdx, this->calibrationFileName);

    if(this->calibrationFileName != lastCalFileName){

        this->processCalibrationFile();

    }

    int arrayCallbacks;

    getIntegerParam(NDArrayCallbacks, &arrayCallbacks);

    if(arrayCallbacks==1){

        epicsTimeStamp before;

        epicsTimeGetCurrent(&before);

        NDPluginDriver::beginProcessCallbacks(pArray);

        this->pNDArrayPool->convert(pArray,&(this->inputArray), NDUInt16);

        if(NULL == this->outputArray){

            this->pNDArrayPool->convert(pArray,&(this->outputArray),NDUInt16);

        }

        //unlock while the plug-and-chug happens. No shared resources are accessed at this time.

        inputArray->getInfo(&arrayInfo);

        this->unlock();

        this->doTemperatureConversion(this->inputArray, this->outputArray, &arrayInfo);

        this->lock();

        setIntegerParam(NDArraySizeX, (int)outputArray->dims[arrayInfo.xDim].size);

        setIntegerParam(NDArraySizeY, (int)outputArray->dims[arrayInfo.yDim].size);

       epicsTimeStamp after;

        epicsTimeGetCurrent(&after);

        double delta = epicsTimeDiffInSeconds(&after, &before);

        cout<<"Took "<<delta<<" s"<<endl;

        setDoubleParam(runTimeIdx, delta);

        NDPluginDriver::endProcessCallbacks(outputArray, false, true);

        callParamCallbacks();

    }

}

 

From: Mark Rivers <rivers at cars.uchicago.edu>
Sent: Tuesday, May 3, 2022 11:37 AM
To: tech-talk at aps.anl.gov; Daykin, Evan <daykin at frib.msu.edu>
Subject: Re: NDArrayPool:reserve ERROR, reference count = 0, should be = 1

 

[EXTERNAL] This email originated from outside of FRIB

Hi Evan,

 

That error probably means you have called NDArray::release() on an array whose reference count is already 0.

 

Most plugins don't need to call release() because it is handled in the base class NDPluginDriver::endProcessCallbacks().

 

Mark

 

 

 

---

From: Tech-talk <tech-talk-bounces at aps.anl.gov> on behalf of Daykin, Evan via Tech-talk <tech-talk at aps.anl.gov>
Sent: Tuesday, May 3, 2022 10:20 AM
To: tech-talk at aps.anl.gov <tech-talk at aps.anl.gov>
Subject: NDArrayPool:reserve ERROR, reference count = 0, should be = 1

 

Hi,

 

I am hoping there’s an AreaDetector plugin maven here…

I have written a small AD plugin intended to convert our raw camera images into a temperature heatmap, based on a calibrated gain, emissivity and exposure time. To test it, I set up a SimDetector in “peak” mode. I connect my plugin to this simDetector image. I can successfully capture and convert 3 frames. On the fourth frame, my test dies with the following error. Are there any common pitfalls that might cause this?

 

NDArray.uniqueId=1

Do temperature conversion start

Took 0.0937809 s

NDArray.uniqueId=2

Do temperature conversion start

Took 0.0655851 s

NDArray.uniqueId=3

Do temperature conversion start

Took 0.0642867 s

NDArray.uniqueId=4

NDArrayPool:reserve ERROR, reference count = 0, should be >= 1, pArray=0x7f453c001d80

Thread SimDetTask (0x5621bbbb0c80) can't proceed, suspending.

Dumping a stack trace of thread 'SimDetTask':

[    0x7f45538ffab3]: /lib/x86_64-linux-gnu/libCom.so.3.15.9(epicsStackTrace+0x73)

[    0x7f45538f0216]: /lib/x86_64-linux-gnu/libCom.so.3.15.9(cantProceed+0xc6)

[    0x7f4553197b08]: /lib/x86_64-linux-gnu/libADBase.so.3.11(_ZN11NDArrayPool7reserveEP7NDArray+0x78)

[    0x7f455305db37]: /lib/x86_64-linux-gnu/libNDPlugin.so.3.11(_ZN14NDPluginDriver21beginProcessCallbacksEP7NDArray+0x367)

[    0x7f455375df1e]: /home/daykin/git/areadetector-temperature/lib/linux-x86_64/libNDPluginTemperature.so(_ZN19NDPluginTemperature16processCallbacksEP7NDArray+0xae)

[    0x7f455305dd53]: /lib/x86_64-linux-gnu/libNDPlugin.so.3.11(_ZN14NDPluginDriver14driverCallbackEP8asynUserPv+0x1d3)

[    0x7f4553851155]: /lib/x86_64-linux-gnu/libasyn.so.4.38(_ZN14asynPortDriver25doCallbacksGenericPointerEPvii+0x1f5)

[    0x7f4553809974]: /usr/lib/epics/lib/linux-x86_64/libsimDetector.so(_ZN11simDetector7simTaskEv+0x4e4)

[    0x7f45538fa0bb]: /lib/x86_64-linux-gnu/libCom.so.3.15.9(epicsSnprintf+0x7bb)

[    0x7f4553387ea7]: /lib/x86_64-linux-gnu/libpthread.so.0(start_thread+0xd7)

[    0x7f455349edef]: /lib/x86_64-linux-gnu/libc.so.6(clone+0x3f)

 

Evan Daykin Controls Engineer Facility for Rare Isotope Beams Michigan State University 640 South Shaw Lane East Lansing, MI 48824, USA Tel. 517-908-7678 Email: daykin at frib.msu.edu