gr-cuda

CUDA Support for GNU Radio using the custom buffer changes introduced in GR 3.10. Custom buffers for CUDA-enabled hardware are provided that can be included in any OOT. This allows the work() or general_work() function of a block to have data provided in the input- and output- buffers that has already been transitioned to device memory so that data movement does not have to take place in the work() function itself.

Acknowledgement

This OOT is adapted/copied from the gr-cuda_buffer OOT work by Black Lynx, Inc. (https://github.com/BlackLynx-Inc/gr-cuda_buffer) and relies on the custom buffer feature developed by David Sorber and documented here: https://wiki.gnuradio.org/index.php/CustomBuffers

Prerequisites

1. NVIDIA CUDA supported GPU
2. Installation of CUDA
3. GNU Radio >= 3.10.0.0

Usage

This OOT can be included in your OOT as follows

./CMakeLists.txt

project(gr-myoot CXX C CUDA)

./lib/CMakeLists.txt

1. Find the exported CMake from gr-cuda as follows

find_package(gnuradio-cuda REQUIRED)

2. Create a library to hold the CUDA specific code:

add_library(gnuradio-myoot-cu STATIC 
    my_kernel.cu
)
set_target_properties(gnuradio-myoot-cu PROPERTIES 
    POSITION_INDEPENDENT_CODE ON
    CUDA_VISIBILITY_PRESET "hidden"
    CUDA_SEPARABLE_COMPILATION ON
)

# Make a fat binary for supported architectures
# Compile for supported archs; CMake workaround, see: https://stackoverflow.com/a/54505975/73878
target_compile_options(gnuradio-myoot-cu PRIVATE "$<$<COMPILE_LANGUAGE:CUDA>:SHELL:-gencode arch=compute_60,code=sm_60>")
target_compile_options(gnuradio-myoot-cu PRIVATE "$<$<COMPILE_LANGUAGE:CUDA>:SHELL:-gencode arch=compute_61,code=sm_61>")
target_compile_options(gnuradio-myoot-cu PRIVATE "$<$<COMPILE_LANGUAGE:CUDA>:SHELL:-gencode arch=compute_62,code=sm_62>")
target_compile_options(gnuradio-myoot-cu PRIVATE "$<$<COMPILE_LANGUAGE:CUDA>:SHELL:-gencode arch=compute_70,code=sm_70>")
target_compile_options(gnuradio-myoot-cu PRIVATE "$<$<COMPILE_LANGUAGE:CUDA>:SHELL:-gencode arch=compute_72,code=sm_72>")
target_compile_options(gnuradio-myoot-cu PRIVATE "$<$<COMPILE_LANGUAGE:CUDA>:SHELL:-gencode arch=compute_75,code=sm_75>")
# target_compile_options(gnuradio-myoot-cu PRIVATE "$<$<COMPILE_LANGUAGE:CUDA>:SHELL:-gencode arch=compute_80,code=sm_80>")
# target_compile_options(gnuradio-myoot-cu PRIVATE "$<$<COMPILE_LANGUAGE:CUDA>:SHELL:-gencode arch=compute_86,code=sm_86>")

3. Link to gr-cuda

The target_link_libraries statement should be changed to specify public linkage

target_link_libraries(gnuradio-myoot PUBLIC gnuradio::gnuradio-runtime gnuradio-cuda)

4. Link to the custom CUDA code

target_link_libraries(gnuradio-myoot PRIVATE gnuradio-myoot-cu)

Creating a Block in an OOT with CUDA acceleration

1. Create a .cu file that will hold the CUDA kernel and wrapper and be compiled with nvcc and linked to the block

See multiply_const.cu for an example

2. Use gr_modtool to create a block in your OOT

See multiply_const.h, multiply_const_impl.{cc,h}

3. Set the io_signature to specify the custom buffer

4. Call the kernel wrapper inside the work() function