X-Git-Url: http://git.tremily.us/?p=parallel_computing.git;a=blobdiff_plain;f=src%2Fcuda_by_example%2FmyFirstKernel.cu;fp=src%2Fcuda_by_example%2FmyFirstKernel.cu;h=8e239355521836451e1b4a4e894ae4b0a1780a2f;hp=0000000000000000000000000000000000000000;hb=e696306bae683aebe418bf3de8fdeedf967ac4a7;hpb=647aaaa5dd881e31b0f79ffc21411e16d1a8ed34 diff --git a/src/cuda_by_example/myFirstKernel.cu b/src/cuda_by_example/myFirstKernel.cu new file mode 100644 index 0000000..8e23935 --- /dev/null +++ b/src/cuda_by_example/myFirstKernel.cu @@ -0,0 +1,113 @@ +/* + * Copyright 1993-2008 NVIDIA Corporation. All rights reserved. + * + * NOTICE TO USER: + * + * This source code is subject to NVIDIA ownership rights under U.S. and + * international Copyright laws. Users and possessors of this source code + * are hereby granted a nonexclusive, royalty-free license to use this code + * in individual and commercial software. + * + * NVIDIA MAKES NO REPRESENTATION ABOUT THE SUITABILITY OF THIS SOURCE + * CODE FOR ANY PURPOSE. IT IS PROVIDED "AS IS" WITHOUT EXPRESS OR + * IMPLIED WARRANTY OF ANY KIND. NVIDIA DISCLAIMS ALL WARRANTIES WITH + * REGARD TO THIS SOURCE CODE, INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE. + * IN NO EVENT SHALL NVIDIA BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL, + * OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS + * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE + * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE + * OR PERFORMANCE OF THIS SOURCE CODE. + * + * U.S. Government End Users. This source code is a "commercial item" as + * that term is defined at 48 C.F.R. 2.101 (OCT 1995), consisting of + * "commercial computer software" and "commercial computer software + * documentation" as such terms are used in 48 C.F.R. 12.212 (SEPT 1995) + * and is provided to the U.S. Government only as a commercial end item. + * Consistent with 48 C.F.R.12.212 and 48 C.F.R. 227.7202-1 through + * 227.7202-4 (JUNE 1995), all U.S. Government End Users acquire the + * source code with only those rights set forth herein. + * + * Any use of this source code in individual and commercial software must + * include, in the user documentation and internal comments to the code, + * the above Disclaimer and U.S. Government End Users Notice. + */ + +// includes, system +#include +#include + +// Simple utility function to check for CUDA runtime errors +void checkCUDAError(const char *msg); + +// Part 3 of 5: implement the kernel +__global__ void myFirstKernel(int *d_a) +{ + int idx = blockIdx.x * blockDim.x + threadIdx.x; + d_a[idx] = 1000 * blockIdx.x + threadIdx.x; +} + +//////////////////////////////////////////////////////////////////////////////// +// Program main +//////////////////////////////////////////////////////////////////////////////// +int main(int argc, char **argv) +{ + + // pointer for host memory + int *h_a; + + // pointer for device memory + int *d_a; + + // define grid and block size + int numBlocks = 8; + int numThreadsPerBlock = 8; + + // Part 1 of 5: allocate host and device memory + size_t memSize = numBlocks * numThreadsPerBlock * sizeof(int); + h_a = (int *)malloc(memSize); + cudaMalloc((void **)&d_a, memSize); + + // Part 2 of 5: launch kernel + dim3 dimGrid(numBlocks); + dim3 dimBlock(numThreadsPerBlock); + myFirstKernel <<< dimGrid, dimBlock >>> (d_a); + + // block until the device has completed + cudaThreadSynchronize(); + + // check if kernel execution generated an error + checkCUDAError("kernel execution"); + + // Part 4 of 5: device to host copy + cudaMemcpy(h_a, d_a, memSize, cudaMemcpyDeviceToHost); + + // Check for any CUDA errors + checkCUDAError("cudaMemcpy"); + + // Part 5 of 5: verify the data returned to the host is correct + for (int i = 0; i < numBlocks; i++) { + for (int j = 0; j < numThreadsPerBlock; j++) { + assert(h_a[i * numThreadsPerBlock + j] == 1000 * i + j); + }} + // free device memory + cudaFree(d_a); + + // free host memory + free(h_a); + + // If the program makes it this far, then the results are correct and + // there are no run-time errors. Good work! + printf("Correct!\n"); + return 0; +} + +void checkCUDAError(const char *msg) +{ + cudaError_t err = cudaGetLastError(); + if (cudaSuccess != err) { + fprintf(stderr, "Cuda error: %s: %s.\n", msg, + cudaGetErrorString(err)); + exit(-1); + } +}