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user105939
Asked: 2014-10-25 09:33:26 +0800 CST

How to make OpenCL work on 14.10 + Nvidia 331.89 drivers?

  • 772

Proprietary drivers 331.89 do not give me OpenCL. (tried both tested/updates) for a while I had version 304.123 that worked - except I wanted the current drivers, and now are unable to downgrade.

Anyway - I could downgrade by workaround, but I wish 331.89 worked.

I used "darktable -d opencl" as test alos added symbolic link to darktable, but that does not help with 331.89

nvidia

3 Answers

  1. Best Answer

    I too was confounded by this perplexing problem until I found a series of forum posts bout Virtual Lighttable in which the participants do some debugging. It turns out that the NVIDIA drivers need a custom modprobe rule that is not installed by default with either nvidia-331 or the the opencl drivers. These rules are provided in the nvidia-modprobe package.

    Here is a list of all of the packages you will need to get OpenCL working on Ubuntu 14.10 with NVIDIA drivers:

    sudo apt-get install nvidia-331 nvidia-331-uvm nvidia-opencl-dev nvidia-modprobe

    EDIT: In case anyone encounters a similar problem on Ubuntu 15.04 and the NVIDIA 346.59 drivers, the command to fix the issue is nearly identical:

    sudo apt-get install nvidia-346 nvidia-346-uvm nvidia-opencl-dev nvidia-modprobe
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  2. Ubuntu 20.04 install

    Things got much better now. Find available driver versions:

    apt-cache search nvidia-driver

    Install the latest one listed + opencl:

    sudo apt install nvidia-driver-435 nvidia-opencl-dev

    You can also search under:

    software-properties-gtk

    in the "Additional Drivers" tab for the latest driver.

    Ubuntu 15.10 install

    sudo apt-get install nvidia-352 nvidia-352-dev nvidia-prime nvidia-modprobe nvidia-opencl-dev
sudo ln -s /usr/include/nvidia-352/GL /usr/local/include
sudo ln -s /usr/lib/x86_64-linux-gnu/libOpenCL.so.1 /usr/local/lib/libOpenCL.so

    Test it out

    Compile and run:

    gcc -o main main.c -lOpenCL
./main

    Here's a minimal test program:

    main.c

    #include <assert.h>
#include <stdlib.h>
#include <stdio.h>

#include <CL/cl.h>

int main() {
    cl_command_queue command_queue;
    cl_context context;
    cl_device_id device;
    cl_int input = 1;
    cl_int kernel_result = 0;
    cl_kernel kernel;
    cl_mem buffer;
    cl_platform_id platform;
    cl_program program;
    const char *source = "__kernel void increment(int in, __global int* out) { out[0] = in + 1; }";

    clGetPlatformIDs(1, &platform, NULL);
    clGetDeviceIDs(platform, CL_DEVICE_TYPE_ALL, 1, &device, NULL);
    context = clCreateContext(NULL, 1, &device, NULL, NULL, NULL);
    command_queue = clCreateCommandQueue(context, device, 0, NULL);
    buffer = clCreateBuffer(context, CL_MEM_READ_WRITE | CL_MEM_ALLOC_HOST_PTR, sizeof(cl_int), NULL, NULL);
    program = clCreateProgramWithSource(context, 1, &source, NULL, NULL);
    clBuildProgram(program, 1, &device, "", NULL, NULL);
    kernel = clCreateKernel(program, "increment", NULL);
    clSetKernelArg(kernel, 0, sizeof(cl_int), &input);
    clSetKernelArg(kernel, 1, sizeof(cl_mem), &buffer);
    clEnqueueTask(command_queue, kernel, 0, NULL, NULL);
    clFlush(command_queue);
    clFinish(command_queue);
    clEnqueueReadBuffer(command_queue, buffer, CL_TRUE, 0, sizeof (cl_int), &kernel_result, 0, NULL, NULL);

    assert(kernel_result == 2);
    return EXIT_SUCCESS;
}

    GitHub upstream.

    Notes

    I really recommend upgrading to 15.10 to get this to work: I had never managed before.

    Tested on:

    • Lenovo ThinkPad T430 with NVIDIA NVS 5400M
    • Lenovo ThinkPad W540 with NVIDIA Quadro K1100M
    • Lenovo ThinkPad P51 with an NVIDIA Quadro M1200 + Ubuntu 21.10 + driver nvidia-driver-470

    Related: https://stackoverflow.com/questions/7542808/how-to-compile-opencl-on-ubuntu/33483311#33483311

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  3. For Ubuntu 14.04 nvidia-modprobe messed up my system. But I realized that the nvidia-331-uvm is not activated from the start (god knows why). So let's activate it:

    $ sudo modprobe nvidia-331-uvm
$ sudo mknod -m 666 /dev/nvidia-uvm c 249 0

    And then:

    $ sudo clinfo

    Then you'll be able to use opencl even as a non-root user. Why it's like this is explained in the Virtual Lighttable mailing list.

    Thus, I finally added the next lines in my /etc/rc.local file:

    # begin opencl config
modprobe nvidia-331-uvm
mknod -m 666 /dev/nvidia-uvm c 249 0
clinfo
# end opencl config

    Then everything works smoothly ;)

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