У меня есть некоторый код OpenCL, который отлично работает следующим образом:
# ocl_helpers.h
typedef struct {
cl_context context;
cl_command_queue queue;
cl_device_id device;
cl_platform_id platform;
} OpenCLEnvironment;
OpenCLEnvironment * get_ocl_env() {
cl_int status;
cl_uint num_platforms = 0;
cl_platform_id *platforms = NULL;
status = clGetPlatformIDs(0, NULL, &num_platforms);
platforms = (cl_platform_id*)malloc(sizeof(cl_platform_id) * num_platforms);
if(platforms == NULL) {
fprintf(stdout, "Malloc failed for platforms...\n");
exit(1);
}
status = clGetPlatformIDs(num_platforms, platforms, NULL);
cl_uint num_devices = 0;
cl_device_id *devices = NULL;
status = clGetDeviceIDs(platforms[0], CL_DEVICE_TYPE_ALL, 0, NULL, &num_devices);
devices = (cl_device_id*)malloc(sizeof(cl_device_id) * num_devices);
if(devices == NULL) {
fprintf(stdout, "Malloc failed for devices...\n");
exit(1);
}
status = clGetDeviceIDs(platforms[0], CL_DEVICE_TYPE_ALL, num_devices, devices, NULL);
cl_context context = CHECK_WITH_ERR_ARG(clCreateContext, status, NULL, num_devices, devices, NULL, NULL);
cl_command_queue command_queue = CHECK_WITH_ERR_ARG(clCreateCommandQueue, status, context, devices[0], 0);
OpenCLEnvironment *ocl_env = (OpenCLEnvironment *)malloc(sizeof(OpenCLEnvironment));
if(ocl_env == NULL) {
fprintf(stdout, "Malloc failed for OCL env...\n");
exit(1);
}
ocl_env->context = context;
ocl_env->queue = command_queue;
ocl_env->device = devices[0];
ocl_env->platform = platforms[0];
// Free the devices list here - no need to keep it since we copied over device
free(devices);
// Likewise for platforms
free(platforms);
return ocl_env;
}
# matmul.c
// System includes
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
// Single header for OpenCL and associated helpers
#include "ocl_helpers.h"
const char* program_source =
"__kernel \n"
"void vecmad(__global float *A, \n"
" __global float *B, \n"
" __global float *C, \n"
" int M, int N, int K) { \n"
" int idx = get_global_id(0); \n"
" int col = idx % M; \n"
" int row = (idx - col); \n"
" C[row + col] = 0.0f; \n"
" for(int k = 0; k < K; ++k) { \n"
" C[row + col] += A[row + k] * B[k*N + col]; \n"
" } \n"
"} \n";
int main(int argc, char **args) {
// Initialise host-side memory
int N = 16;
int n_elements = N*N;
int data_size = n_elements * sizeof(float);
printf("%d, %d\n", n_elements, data_size);
float *A = get_ptr(n_elements), *B = get_ptr(n_elements), *C = get_ptr(n_elements);
for(int i = 0; i < n_elements; ++i) {
float val = (float)(i % N);
A[i] = val;
B[i] = val;
C[i] = 0.0f;
}
print_sq_matrix(A, N);
print_sq_matrix(B, N);
printf("Host-memory initialised...\n");
cl_int status;
OpenCLEnvironment *env = get_ocl_env();
// Get max sizes // Offending block
size_t store[3] = { 0 }; // Offending block
CHECK_WITH_ERR_RES(clGetDeviceInfo, status, env->device, // Offending block
CL_DEVICE_MAX_WORK_ITEM_SIZES, sizeof(store), store, NULL);// Offending block
cl_mem buf_A = CHECK_WITH_ERR_ARG(clCreateBuffer, status,
env->context, CL_MEM_READ_ONLY,
data_size, NULL);
cl_mem buf_B = CHECK_WITH_ERR_ARG(clCreateBuffer, status,
env->context, CL_MEM_READ_ONLY,
data_size, NULL);
cl_mem buf_C = CHECK_WITH_ERR_ARG(clCreateBuffer, status,
env->context, CL_MEM_WRITE_ONLY,
data_size, NULL);
CHECK_WITH_ERR_RES(clEnqueueWriteBuffer, status, env->queue,
buf_A, CL_FALSE, 0, data_size, A, 0, NULL, NULL);
CHECK_WITH_ERR_RES(clEnqueueWriteBuffer, status, env->queue,
buf_B, CL_FALSE, 0, data_size, B, 0, NULL, NULL);
printf("OpenCL machinery and buffers initialised, buffers written to...\n");
cl_program program = CHECK_WITH_ERR_ARG(clCreateProgramWithSource, status,
env->context, 1,
(const char**)&program_source, NULL);
CHECK_WITH_ERR_RES(clBuildProgram, status, program, 1, &(env->device),
NULL, NULL, NULL);
printf("Program built...\n");
cl_kernel kernel = CHECK_WITH_ERR_ARG(clCreateKernel, status, program,
"vecmad");
set_kernel_args(&kernel, buf_A, buf_B, buf_C, N, N, N);
size_t globalws[1] = {256};
status = clEnqueueNDRangeKernel(env->queue, kernel, 2, NULL, globalws, NULL, 0, NULL, NULL);
if(status != CL_SUCCESS) {
printf("%d\n", status);
exit(1);
}
printf("Kernel queued...\n");
// Wait on the kernel to finish
CHECK_WITH_ERR_RES(clFinish, status, env->queue);
// Read buffer and do some stuff
...
}
Проблема с этим кодом заключается в том, что, если я закомментирую весь «нарушающий» блок, как указано выше, ядро зависает, выводя следующее:
$ ./matmul
...
Host-memory initialised...
OpenCL machinery and buffers initialised, buffers written to...
Program built...
Kernel args set...
Kernel queued...
# hangs here
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * - закомментированный вызов clGetDeviceInfo, я получаю ошибку -63 (CL_INVALID_GLOBAL_WORK_SIZE). Я что-то не так делаю с устройством и платформой в get_ocl_env()?