func (this *context) CreateEvent() (Event, error) {
var errCode cl.CL_int
if event_id := cl.CLCreateUserEvent(this.context_id, &errCode); errCode != cl.CL_SUCCESS {
return nil, fmt.Errorf("CreateUserEvent failure with errcode_ret %d: %s", errCode, cl.ERROR_CODES_STRINGS[-errCode])
} else {
return &event{event_id}, nil
}
}
func main() {
/* OpenCL data structures */
var device []cl.CL_device_id
var context cl.CL_context
var queue cl.CL_command_queue
var program *cl.CL_program
var kernel cl.CL_kernel
var err cl.CL_int
/* Data and events */
var data []float32
var data_buffer cl.CL_mem
var user_event, kernel_event, read_event [1]cl.CL_event
/* Initialize data */
data = make([]float32, 4)
for i := 0; i < 4; i++ {
data[i] = float32(i) * 1.0
}
/* Create a device and context */
device = utils.Create_device()
context = cl.CLCreateContext(nil, 1, device[:], nil, nil, &err)
if err < 0 {
println("Couldn't create a context")
return
}
/* Build the program and create a kernel */
program = utils.Build_program(context, device[:], PROGRAM_FILE, nil)
kernel = cl.CLCreateKernel(*program, KERNEL_FUNC, &err)
if err < 0 {
println("Couldn't create a kernel")
return
}
/* Create a buffer to hold data */
data_buffer = cl.CLCreateBuffer(context,
cl.CL_MEM_READ_WRITE|cl.CL_MEM_COPY_HOST_PTR,
cl.CL_size_t(unsafe.Sizeof(data[0]))*4, unsafe.Pointer(&data[0]), &err)
if err < 0 {
println("Couldn't create a buffer")
return
}
/* Create kernel argument */
err = cl.CLSetKernelArg(kernel, 0, cl.CL_size_t(unsafe.Sizeof(data_buffer)), unsafe.Pointer(&data_buffer))
if err < 0 {
println("Couldn't set a kernel argument")
return
}
/* Create a command queue */
queue = cl.CLCreateCommandQueue(context, device[0],
cl.CL_QUEUE_OUT_OF_ORDER_EXEC_MODE_ENABLE, &err)
if err < 0 {
println("Couldn't create a command queue")
return
}
/* Configure events */
user_event[0] = cl.CLCreateUserEvent(context, &err)
if err < 0 {
println("Couldn't enqueue the kernel")
return
}
/* Enqueue kernel */
err = cl.CLEnqueueTask(queue, kernel, 1, user_event[:], &kernel_event[0])
if err < 0 {
println("Couldn't enqueue the kernel")
return
}
/* Read the buffer */
err = cl.CLEnqueueReadBuffer(queue, data_buffer, cl.CL_FALSE, 0,
cl.CL_size_t(unsafe.Sizeof(data[0]))*4, unsafe.Pointer(&data[0]), 1, kernel_event[:], &read_event[0])
if err < 0 {
println("Couldn't read the buffer")
return
}
/* Set callback for event */
err = cl.CLSetEventCallback(read_event[0], cl.CL_COMPLETE,
read_complete, unsafe.Pointer(&data))
if err < 0 {
println("Couldn't set callback for event")
return
}
/* Sleep for a second to demonstrate the that commands haven't
started executing. Then prompt user */
time.Sleep(1)
fmt.Printf("Old data: %4.2f, %4.2f, %4.2f, %4.2f\n",
data[0], data[1], data[2], data[3])
fmt.Printf("Press ENTER to continue.\n")
//getchar();
reader := bufio.NewReader(os.Stdin)
reader.ReadString('\n')
/* Set user event to success */
cl.CLSetUserEventStatus(user_event[0], cl.CL_SUCCESS)
/* Deallocate resources */
cl.CLReleaseEvent(read_event[0])
cl.CLReleaseEvent(kernel_event[0])
cl.CLReleaseEvent(user_event[0])
cl.CLReleaseMemObject(data_buffer)
cl.CLReleaseKernel(kernel)
cl.CLReleaseCommandQueue(queue)
cl.CLReleaseProgram(*program)
cl.CLReleaseContext(context)
}