invalid configuration argument

Accelerated Computing CUDA CUDA Programming and Performance
1

I have the following code:

__global __ void zeros(int * in, int * out, int width, int height, int channels) {

		int ii;

	int xIndex = threadIdx.x + blockIdx.x*blockDim.x;

	int yIndex = threadIdx.y + blockIdx.y*blockDim.y;

	int index = channels*(xIndex + yIndex*width);

	if (xIndex < width && yIndex < height) {

		for (ii = 0; ii < channels; ii++)

			out[index+ii] = 0;

	}

}

set the block and grid dim

dim3 CUDA_BlockDimensions;

dim3 CUDA_GridDimensions;

CUDA_BlockDimensions.x = 16;

CUDA_BlockDimensions.y = 16;

CUDA_GridDimensions.x = 32;

CUDA_GridDimensions.y = 32;

And launch it using:

cudaGetLastError();

zeros<<<CUDA_BlockDimensions, CUDA_GridDimensions>>>(CUDA_input1, CUDA_output1, input2, input3, input4);

CUDALink_Err = cudaGetLastError();

if( CUDA_Err != cudaSuccess)

{

funStruct->Message("launch");

printf("BlockDimensions x=%d, y=%d, z=%d\n", CUDA_BlockDimensions.x, CUDA_BlockDimensions.y, CUDA_BlockDimensions.z);

printf("GridDimensions x=%d, y=%d, z=%d\n", CUDA_GridDimensions.x, CUDA_GridDimensions.y, CUDA_GridDimensions.z);

printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");

printf("ERRROR on line %d in %s:%s\n", __LINE__, __FILE__, __func__);

printf("CUDA Error %s\n", cudaGetErrorString(CUDA_Err));

printf("<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");

return dllErr;

}

Here is the result from the printf:

<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

BlockDimensions x=16, y=16, z=1

GridDimensions x=32, y=32, z=1

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

ERRROR on line 136 in CUDALink_CUDAZero

CUDA Error invalid configuration argument

<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

the block and grid dimensions seem reasonable to me.

thanks

2

You are supplying the block and grid arguments to the kernel call in the wrong order. Try this:

zeros<<<CUDA_GridDimensions,CUDA_BlockDimensions>>>(CUDA_input1, CUDA_output1, input2, input3, input4);

The reason it doesn’t work for you is because you are asking for 1024 threads per block in your current call (which exceeds the 512 limit).

3

ahh. switching the arguments fixed the issue. Thanks