Host Memory Copy Kernel¶
This is a Host Memory Example to describe how data can be copied between host-only buffer and device-only buffer using User Copy Kernel.
KEY CONCEPTS: host memory
KEYWORDS: XCL_MEM_EXT_HOST_ONLY, CL_MEM_HOST_NO_ACCESS, enqueueMapBuffer
Here a user copy kernel is instantiated inside container which copies data between host and device memory.
Host only buffer is created using
XCL_MEM_EXT_HOST_ONLY flag whereas device only buffer is created using
CL_MEM_HOST_NO_ACCESS flag. The following data transfers take place in the example -
copy_kernelto copy the HOST_ONLY input buffer
buffer_in_hostinto DEVICE_ONLY input buffer
krnl_vaddto do computations on DEVICE_ONLY input buffer
buffer_in_devand put output in DEVICE_ONLY output buffer
copy_kernelto copy the DEVICE_ONLY output buffer
buffer_out_devinto HOST_ONLY output buffer
Platforms containing following strings in their names are not supported for this example :
_u25_ u30 u50lv u50_gen3x4 zc vck aws-vu9p-f1 2019 2018 _u2_
Application code is located in the src directory. Accelerator binary files will be compiled to the xclbin directory. The xclbin directory is required by the Makefile and its contents will be filled during compilation. A listing of all the files in this example is shown below
src/copy_kernel.cpp src/host.cpp src/krnl_vadd.cpp
Access these files in the github repo by clicking here.
COMMAND LINE ARGUMENTS¶
Once the environment has been configured, the application can be executed by
./host_memory_copy_kernel.exe <krnl_vadd XCLBIN>