Help with OpenCL under Linux and nouveau

xilman · 2019-11-13, 12:17

I've never writted anything in OpenCL and would appreciate some help from the good folk here. For information: I'm running Ubuntu 19.10 and would prefer to use the C API, though C++ would do at a pinch. The hardware has 6 cores and an Nvidia GTX1060. After wasting many hours trying to get the Nvidia drivers and CUDA working i gave up and reverted to the free nouveau free device driver. I've run apt-get for most everything I can find which refers to OpenCL.

There are two major issues. The show stopper is that clinfo reports "Number of platforms 0". I would have thought that it would have found the cpus at the very least.

The other is that I have yet to find a good tutorial for the language which goes beyond presenting the source code of (effectively) "Hello world." I have downloaded the C API spec.

Can anyone help?

Thanks,

Paul

preda · 2019-11-13, 19:34

Indeed, you want to get clinfo to report more that 0 platforms/devices.

You need an OpenCL implementation even for the CPUs. I seem to remember that Intel offers one for download (for Intel CPUs) but I don't have a link. OTOH I don't expect OpenCL on CPUs to be actually useful other than for trying out/debugging.

For an Nvidia GPU, it is my impression that the CUDA *toolkit* brings the OpenCL driver. (I don't have experience with Nouveau)

For an AMD GPU, one may use either ROCm, or amdgpu-pro, which both have different OpenCL compilers.

So the first step is to get clinfo to recognize something.

Afterwards when starting programming, you may have a look at clwrap.h in gpuowl source code for some utils like compiling a kernel etc.

xilman · 2019-11-14, 09:19

I think I found the problem. It looks like "apt install mesa-opencl-icd" wasn't successful. Trying it just now indicates that the system gcc is too new for that package --- 9.2.1-9ubuntu2 is installed but 9.1.0-2ubuntu2~19.04 is required.

Ho hum.

2019-11-13, 12:17	#1
xilman Bamboozled! "𒉺𒌌𒇷𒆷𒀭" May 2003 Down not across 26616₈ Posts	Help with OpenCL under Linux and nouveau I've never writted anything in OpenCL and would appreciate some help from the good folk here. For information: I'm running Ubuntu 19.10 and would prefer to use the C API, though C++ would do at a pinch. The hardware has 6 cores and an Nvidia GTX1060. After wasting many hours trying to get the Nvidia drivers and CUDA working i gave up and reverted to the free nouveau free device driver. I've run apt-get for most everything I can find which refers to OpenCL. There are two major issues. The show stopper is that clinfo reports "Number of platforms 0". I would have thought that it would have found the cpus at the very least. The other is that I have yet to find a good tutorial for the language which goes beyond presenting the source code of (effectively) "Hello world." I have downloaded the C API spec. Can anyone help? Thanks, Paul Last fiddled with by xilman on 2019-11-13 at 12:17

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2019-11-13, 19:34	#2
preda "Mihai Preda" Apr 2015 5·17² Posts	Indeed, you want to get clinfo to report more that 0 platforms/devices. You need an OpenCL implementation even for the CPUs. I seem to remember that Intel offers one for download (for Intel CPUs) but I don't have a link. OTOH I don't expect OpenCL on CPUs to be actually useful other than for trying out/debugging. For an Nvidia GPU, it is my impression that the CUDA toolkit brings the OpenCL driver. (I don't have experience with Nouveau) For an AMD GPU, one may use either ROCm, or amdgpu-pro, which both have different OpenCL compilers. So the first step is to get clinfo to recognize something. Afterwards when starting programming, you may have a look at clwrap.h in gpuowl source code for some utils like compiling a kernel etc.

2019-11-14, 09:19	#3
xilman Bamboozled! "𒉺𒌌𒇷𒆷𒀭" May 2003 Down not across 2·7³·17 Posts	I think I found the problem. It looks like "apt install mesa-opencl-icd" wasn't successful. Trying it just now indicates that the system gcc is too new for that package --- 9.2.1-9ubuntu2 is installed but 9.1.0-2ubuntu2~19.04 is required. Ho hum.