[Starpu-devel] How does StarPU get the OpenCL device ID ?

[Sébastien Frémal <sebastien.fremal@gmail.com>]

Hello,

I've executed the hello_world example of starpu with a library doing RPC for opencl calls. When I execute the example on the same machine than the server, all work fine :

Executing : clCreateContext

Adresse du context : 0x7f332c297e80

Executing : clCreateCommandQueue

Adresse de la queue : 139857766440128

Executing : clGetDeviceInfo

Executing : clCreateCommandQueue

Adresse de la queue : 139857766471632

Executing : clGetDeviceInfo

Hello world (params = {1, 2.000000} )

Callback function got argument 0x42

Executing : clReleaseContext

ReleaseContext is a success

Executing : clReleaseCom mandQueue

ReleaseCommandQueue is a success

Executing : clReleaseCommandQueue

ReleaseCommandQueue is a success

When I execute the example in a virtual machine, there is a problem with the device ID : 

Executing : clCreateContext

oops in _starpu_opencl_init_context (drivers/opencl/driver_opencl.c:140) ... <Invalid device> (-33) 

lt-hello_world: ../include/starpu_opencl.h:41: starpu_opencl_report_error: Assertion `0' failed.

The device ID found by StarPU is 0. As the function clGetDeviceIDs is not called, I guess StarPU uses another way to get the device ID (maybe reading the number of the pci port ?), which doesn't work as the virtual environment has no information about the GPU. 

Is it possible to get informations on that topic and where that specific call to clCreateContext is executed please ?

Best regards,

Sebastien Fremal