쓰레드 ID 구하기.

1D grid of 1D blocks

__device__ int getGlobalIdx_1D_1D()

{

return blockIdx.x *blockDim.x + threadIdx.x;

}

1D grid of 2D blocks

__device__ int getGlobalIdx_1D_2D()

{

return blockIdx.x * blockDim.x * blockDim.y + threadIdx.y * blockDim.x + threadIdx.x;

}

1D grid of 3D blocks

__device__ int getGlobalIdx_1D_3D()

{

return blockIdx.x * blockDim.x * blockDim.y * blockDim.z + threadIdx.z * blockDim.y * blockDim.x + threadIdx.y * blockDim.x + threadIdx.x;

} 

2D grid of 1D blocks 

__device__ int getGlobalIdx_2D_1D()

{

int blockId   = blockIdx.y * gridDim.x + blockIdx.x;

int threadId = blockId * blockDim.x + threadIdx.x; 

return threadId;

}

2D grid of 2D blocks  

 __device__ int getGlobalIdx_2D_2D()

{

int blockId = blockIdx.x + blockIdx.y * gridDim.x; 

int threadId = blockId * (blockDim.x * blockDim.y) + (threadIdx.y * blockDim.x) + threadIdx.x;

return threadId;

}

2D grid of 3D blocks

__device__ int getGlobalIdx_2D_3D()

{

int blockId = blockIdx.x 

+ blockIdx.y * gridDim.x; 

int threadId = blockId * (blockDim.x * blockDim.y * blockDim.z)

  + (threadIdx.z * (blockDim.x * blockDim.y))

  + (threadIdx.y * blockDim.x)

  + threadIdx.x;

return threadId;

} 

3D grid of 1D blocks

__device__ int getGlobalIdx_3D_1D()

{

int blockId = blockIdx.x 

+ blockIdx.y * gridDim.x 

+ gridDim.x * gridDim.y * blockIdx.z; 

int threadId = blockId * blockDim.x + threadIdx.x;

return threadId;

} 

3D grid of 2D blocks

__device__ int getGlobalIdx_3D_2D()

{

int blockId = blockIdx.x 

        + blockIdx.y * gridDim.x 

+ gridDim.x * gridDim.y * blockIdx.z; 

int threadId = blockId * (blockDim.x * blockDim.y)

 + (threadIdx.y * blockDim.x)

 + threadIdx.x;

return threadId;

}

3D grid of 3D blocks

__device__ int getGlobalIdx_3D_3D()

{

int blockId = blockIdx.x 

+ blockIdx.y * gridDim.x 

+ gridDim.x * gridDim.y * blockIdx.z; 

int threadId = blockId * (blockDim.x * blockDim.y * blockDim.z)

 + (threadIdx.z * (blockDim.x * blockDim.y))

 + (threadIdx.y * blockDim.x)

 + threadIdx.x;

return threadId;

}