enumerate all available opencl devices

gistfile1.cpp

/*

I modified some code I found to correctly enumerate all OpenCL devices on my laptop...

Here's the output:

NAME: Intel(R) Core(TM) i7-3720QM CPU @ 2.60GHz
ADDRESS_WIDTH: 32
EXTENSIONS: cl_APPLE_SetMemObjectDestructor cl_APPLE_ContextLoggingFunctions cl_APPLE_clut cl_APPLE_query_kernel_names cl_APPLE_gl_sharing cl_khr_gl_event cl_khr_fp64 cl_khr_global_int32_base_atomics cl_khr_global_int32_extended_atomics cl_khr_local_int32_base_atomics cl_khr_local_int32_extended_atomics cl_khr_byte_addressable_store cl_khr_int64_base_atomics cl_khr_int64_extended_atomics cl_khr_3d_image_writes cl_APPLE_fp64_basic_ops cl_APPLE_fixed_alpha_channel_orders cl_APPLE_biased_fixed_point_image_formats

NAME: GeForce GT 650M
ADDRESS_WIDTH: 32
EXTENSIONS: cl_APPLE_SetMemObjectDestructor cl_APPLE_ContextLoggingFunctions cl_APPLE_clut cl_APPLE_query_kernel_names cl_APPLE_gl_sharing cl_khr_gl_event cl_khr_byte_addressable_store cl_khr_global_int32_base_atomics cl_khr_global_int32_extended_atomics cl_khr_local_int32_base_atomics cl_khr_local_int32_extended_atomics cl_APPLE_fp64_basic_ops 
 
 */

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

#define MAC

#ifdef MAC
#include <OpenCL/cl.h>
#else
#include <CL/cl.h>
#endif

int main() {
    
    /* Host/device data structures */
    cl_platform_id platform;
    cl_device_id *devices;
    cl_uint num_devices, addr_data;
    cl_int i, err;
    
    /* Extension data */
    char name_data[256], ext_data[4096];
    
    /* Identify a platform */
    err = clGetPlatformIDs(1, &platform, NULL);
    if(err < 0) {
        perror("Couldn't find any platforms");
        exit(1);
    }
    
    /* Determine number of connected devices */
    err = clGetDeviceIDs(platform,
                         // CL_DEVICE_TYPE_GPU,
                         CL_DEVICE_TYPE_ALL,      // jyl -- query for all available opencl devices
                         1,
                         NULL,
                         &num_devices);
    
    if(err < 0) {
        perror("Couldn't find any devices");
        exit(1);
    }
    
    /* Access connected devices */
    devices = (cl_device_id*) malloc(sizeof(cl_device_id) * num_devices);
    
    clGetDeviceIDs(platform,
                   // CL_DEVICE_TYPE_GPU,
                   CL_DEVICE_TYPE_ALL,          // jyl -- query for all available opencl devices
                   num_devices,
                   devices,
                   NULL);
    
    /* Obtain data for each connected device */
    for(i=0; i<num_devices; i++) {
        
        err = clGetDeviceInfo(devices[i], CL_DEVICE_NAME,
                              sizeof(name_data), name_data, NULL);
        if(err < 0) {
            perror("\nERROR! Couldn't read extension data");
            exit(1);
        }
        clGetDeviceInfo(devices[i], CL_DEVICE_ADDRESS_BITS,
                        sizeof(ext_data), &addr_data, NULL);
        
        clGetDeviceInfo(devices[i], CL_DEVICE_EXTENSIONS,
                        sizeof(ext_data), ext_data, NULL);
        
        printf("\n\nNAME: %s\nADDRESS_WIDTH: %u\nEXTENSIONS: %s",
               name_data, addr_data, ext_data);
    }
    
    free(devices);
    return 0;
}