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chandrasekhar92's avatar
chandrasekhar92
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2 years ago
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Intel FPGA SDK for OpenCL: Issue while launching same opencl kernel multiple times

Hi, I am using Intel FPGA SDK for OpenCL to perform matrix multiplication on DE1-SoC board. As per my requirement I have to perform this multiplication multiple times and hence iterating over a loop...
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  • BoonBengT_Altera's avatar
    BoonBengT_Altera
    2 years ago

    Hi @chandrasekhar92,


    Noted that there seems to be a custom BSP involved. Is it correct to say there is no references design you are referring to and sample code are based on self written?


    After going through the situation, using clWaitForEvents to synchronize kernels in separate queues are working from previous experiences. Would recommend to try clFinish() which has similar purposes to see if that works.


    Also for the mention situation, it seem that the desire execution flow are out of order, hence below links would also explain that:

    - https://www.intel.cn/content/www/cn/zh/developer/articles/technical/opencl-out-of-order-queue-on-intel-processor-graphics.html


    Note: link mention are for example with GPU as the hardware, however the execution concept are the same.


    Best Wishes

    BB


BoonBengT_Altera's avatar
BoonBengT_Altera
Icon for Moderator rankModerator
2 years ago

Hi @chandrasekhar92,


Noted that there seems to be a custom BSP involved. Is it correct to say there is no references design you are referring to and sample code are based on self written?


After going through the situation, using clWaitForEvents to synchronize kernels in separate queues are working from previous experiences. Would recommend to try clFinish() which has similar purposes to see if that works.


Also for the mention situation, it seem that the desire execution flow are out of order, hence below links would also explain that:

- https://www.intel.cn/content/www/cn/zh/developer/articles/technical/opencl-out-of-order-queue-on-intel-processor-graphics.html


Note: link mention are for example with GPU as the hardware, however the execution concept are the same.


Best Wishes

BB


  • chandrasekhar92's avatar
    chandrasekhar92
    Icon for New Contributor rankNew Contributor
    2 years ago

    Hi,

    Thank you for your time.

    I am able to solve the issue after making changes to hardware. The BSP that I made changes is the DE1-SoC BSP provided with OpenCL SDK. I am using GPIO pins to connect with D5M camera which uses same pin from fpga kernel clk. It might be the reason that is interfering with OpenCL kernel queuing. Once I separated them, and I used clFinish() as suggested by you, and able to run and enqueue kernel multiple times.

    Appreciate your help.