<li>An interesting primer is that
of <a href="resources/Seland_2008_Cuda_Programming.pdf">Seland</a>.</li>
<li>Also look at
-
the <a href="http://developer.download.nvidia.com/compute/cuda/3_2/toolkit/docs/CUDA_C_Programming_Guide.pdf">CUDA
- C Programming Guide</a> and other documentation distributed in
-
the <a href="http://www.nvidia.com/object/cuda_get.html">CUDA
- toolkit</a>. Because the toolkit is a critical part of a working
- CUDA installation, it may already be installed on your system.
- On <code>borg3</code>, look in <code>/usr/local/cuda/</code>.</li>
- <li>The CUDA SDK (download links on
-
the <a href="http://www.nvidia.com/object/cuda_get.html">CUDA
- toolkit page</a>) contain lots of useful examples. Your sysadmin
- may have installed it while setting up CUDA on your system.
- On <code>borg3</code> look
- in <code>/usr/local/cuda/doc/NVIDIA_GPU_Computing_SDK/</code>.</li>
+ the <a href="http://developer.download.nvidia.com/compute/cuda/3_2/toolkit/docs/CUDA_C_Programming_Guide.pdf">CUDA
+ C Programming Guide</a> and other documentation distributed in
+ the <a href="http://www.nvidia.com/object/cuda_get.html">CUDA
+ toolkit</a>. Because the toolkit is a critical part of a working
+ CUDA installation, it may already be installed on your system.
+ On <code>borg3</code>, look in <code>/usr/local/cuda/</code>.</li>
+ <li>The CUDA SDK (download links on
+ the <a href="http://www.nvidia.com/object/cuda_get.html">CUDA
+ toolkit page</a>) contain lots of useful examples. Your sysadmin
+ may have installed it while setting up CUDA on your system.
+ On <code>borg3</code> look
+ in <code>/usr/local/cuda/doc/NVIDIA_GPU_Computing_SDK/</code>.</li>
<li>David Kirk, NVDIA, and Wen-Mei Hwua, ECE, U of Illinos, have
written an excellent textbook on
CUDA: <a href="http://www.elsevierdirect.com/morgan_kaufmann/kirk/">Programming
Gems 3</a> contains great demonstration GPU codes.</li>
</ul>
+<h2 id="learn">Learning CUDA by examples</h2>
+<p>Jason Sanders and Edward
+Kandrot's <a href="http://developer.nvidia.com/object/cuda-by-example.html">CUDA
+by Example</a> contains a number of example problems. Here are
+solutions to some of the problems:</p>
+
+<ul>
+ <li><a href="../../src/cuda_by_example/cudaMallocAndMemcpy.cu">cudaMallocAndMemcpy.cu</a></li>
+ <li><a href="../../src/cuda_by_example/myFirstKernel.cu">myFirstKernel.cu</a></li>
+ <li><a href="../../src/cuda_by_example/reverseArray_singleblock.cu">reverseArray_singleblock.cu</a></li>
+ <li><a href="../../src/cuda_by_example/reverseArray_multiblock.cu">reverseArray_multiblock.cu</a></li>
+ <li><a href="../../src/cuda_by_example/reverseArray_multiblock_fast.cu">reverseArray_multiblock_fast.cu</a></li>
+</ul>
<!--#include virtual="$root_directory/shared/footer.shtml"-->
--- /dev/null
+AddType text/plain .cu
--- /dev/null
+/*
+ * 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 <stdio.h>
+#include <assert.h>
+
+// Simple utility function to check for CUDA runtime errors
+void checkCUDAError(const char *msg);
+
+///////////////////////////////////////////////////////////////////////////////
+// Program main
+///////////////////////////////////////////////////////////////////////////////
+int main(int argc, char **argv)
+{
+
+ // pointer and dimension for host memory
+ int n, dimA;
+ float *h_a;
+
+ // pointers for device memory
+ float *d_a, *d_b;
+
+ // allocate and initialize host memory
+ // Bonus: try using cudaMallocHost in place of malloc
+ dimA = 8;
+ h_a = (float *)malloc(dimA * sizeof(float));
+ for (n = 0; n < dimA; n++) {
+ h_a[n] = (float)n;
+ }
+ // Part 1 of 5: allocate device memory
+ size_t memSize = dimA * sizeof(float);
+ cudaMalloc((void **)&d_a, memSize);
+ cudaMalloc((void **)&d_b, memSize);
+
+ // Part 2 of 5: host to device memory copy
+ cudaMemcpy(d_a, h_a, memSize, cudaMemcpyHostToDevice);
+
+ // Part 3 of 5: device to device memory copy
+ cudaMemcpy(d_b, d_a, memSize, cudaMemcpyDeviceToDevice);
+
+ // clear host memory
+ for (n = 0; n < dimA; n++) {
+ h_a[n] = 0.f;
+ }
+
+ // Part 4 of 5: device to host copy
+ cudaMemcpy(h_a, d_b, memSize, cudaMemcpyDeviceToHost);
+
+ // Check for any CUDA errors
+ checkCUDAError("cudaMemcpy calls");
+
+ // verify the data on the host is correct
+ for (n = 0; n < dimA; n++) {
+ assert(h_a[n] == (float)n);
+ }
+ // Part 5 of 5: free device memory pointers d_a and d_b
+ cudaFree(d_b);
+ cudaFree(d_a);
+
+ // Check for any CUDA errors
+ checkCUDAError("cudaFree");
+
+ // free host memory pointer h_a
+ // Bonus: be sure to use cudaFreeHost for memory allocated with cudaMallocHost
+ 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);
+ }
+}
--- /dev/null
+/*
+ * 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 <stdio.h>
+#include <assert.h>
+
+// 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);
+ }
+}
--- /dev/null
+/*
+ * 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 <stdio.h>
+#include <assert.h>
+
+// Simple utility function to check for CUDA runtime errors
+void checkCUDAError(const char *msg);
+
+// Part3: implement the kernel
+__global__ void reverseArrayBlock(int *d_out, int *d_in)
+{
+ int inOffset = blockDim.x * blockIdx.x;
+ int outOffset = blockDim.x * (gridDim.x - 1 - blockIdx.x);
+ int in = inOffset + threadIdx.x;
+ int out = outOffset + (blockDim.x - 1 - threadIdx.x);
+ d_out[out] = d_in[in];
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// Program main
+////////////////////////////////////////////////////////////////////////////////
+int main(int argc, char **argv)
+{
+
+ // pointer for host memory and size
+ int *h_a;
+ int dimA = 256 * 1024; // 256K elements (1MB total)
+
+ // pointer for device memory
+ int *d_b, *d_a;
+
+ // define grid and block size
+ int numThreadsPerBlock = 256;
+
+ // Part 1: compute number of blocks needed based on array size and desired block size
+ int numBlocks = dimA / numThreadsPerBlock;
+
+ // allocate host and device memory
+ size_t memSize = numBlocks * numThreadsPerBlock * sizeof(int);
+ h_a = (int *)malloc(memSize);
+ cudaMalloc((void **)&d_a, memSize);
+ cudaMalloc((void **)&d_b, memSize);
+
+ // Initialize input array on host
+ for (int i = 0; i < dimA; ++i) {
+ h_a[i] = i;
+ }
+ // Copy host array to device array
+ cudaMemcpy(d_a, h_a, memSize, cudaMemcpyHostToDevice);
+
+ // launch kernel
+ dim3 dimGrid(numBlocks);
+ dim3 dimBlock(numThreadsPerBlock);
+ reverseArrayBlock <<< dimGrid, dimBlock >>> (d_b, d_a);
+
+ // block until the device has completed
+ cudaThreadSynchronize();
+
+ // check if kernel execution generated an error
+ // Check for any CUDA errors
+ checkCUDAError("kernel invocation");
+
+ // device to host copy
+ cudaMemcpy(h_a, d_b, memSize, cudaMemcpyDeviceToHost);
+
+ // Check for any CUDA errors
+ checkCUDAError("memcpy");
+
+ // verify the data returned to the host is correct
+ for (int i = 0; i < dimA; i++) {
+ assert(h_a[i] == dimA - 1 - i);
+ }
+ // free device memory
+ cudaFree(d_a);
+ cudaFree(d_b);
+
+ // 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(EXIT_FAILURE);
+ }
+}
--- /dev/null
+/*
+ * 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 <stdio.h>
+#include <assert.h>
+
+// Simple utility function to check for CUDA runtime errors
+void checkCUDAError(const char *msg);
+
+// Part 2 of 2: implement the fast kernel using shared memory
+__global__ void reverseArrayBlock(int *d_out, int *d_in)
+{
+ extern __shared__ int s_data[];
+ int inOffset = blockDim.x * blockIdx.x;
+ int in = inOffset + threadIdx.x;
+
+ // Load one element per thread from device memory and store it
+ // *in reversed order* into temporary shared memory
+ s_data[blockDim.x - 1 - threadIdx.x] = d_in[in];
+
+ // Block until all threads in the block have written their data to shared mem
+ __syncthreads();
+
+ // write the data from shared memory in forward order,
+ // but to the reversed block offset as before
+ int outOffset = blockDim.x * (gridDim.x - 1 - blockIdx.x);
+ int out = outOffset + threadIdx.x;
+ d_out[out] = s_data[threadIdx.x];
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// Program main
+////////////////////////////////////////////////////////////////////////////////
+int main(int argc, char **argv)
+{
+
+ // pointer for host memory and size
+ int *h_a;
+ int dimA = 256 * 1024; // 256K elements (1MB total)
+
+ // pointer for device memory
+ int *d_b, *d_a;
+
+ // define grid and block size
+ int numThreadsPerBlock = 256;
+
+ // Compute number of blocks needed based on array size and desired block size
+ int numBlocks = dimA / numThreadsPerBlock;
+
+ // Part 1 of 2: Compute the number of bytes of shared memory needed
+ // This is used in the kernel invocation below
+ int sharedMemSize = numThreadsPerBlock * sizeof(int);
+
+ // allocate host and device memory
+ size_t memSize = numBlocks * numThreadsPerBlock * sizeof(int);
+ h_a = (int *)malloc(memSize);
+ cudaMalloc((void **)&d_a, memSize);
+ cudaMalloc((void **)&d_b, memSize);
+
+ // Initialize input array on host
+ for (int i = 0; i < dimA; ++i) {
+ h_a[i] = i;
+ }
+ // Copy host array to device array
+ cudaMemcpy(d_a, h_a, memSize, cudaMemcpyHostToDevice);
+
+ // launch kernel
+ dim3 dimGrid(numBlocks);
+ dim3 dimBlock(numThreadsPerBlock);
+ reverseArrayBlock <<< dimGrid, dimBlock, sharedMemSize >>> (d_b, d_a);
+
+ // block until the device has completed
+ cudaThreadSynchronize();
+
+ // check if kernel execution generated an error
+ // Check for any CUDA errors
+ checkCUDAError("kernel invocation");
+
+ // device to host copy
+ cudaMemcpy(h_a, d_b, memSize, cudaMemcpyDeviceToHost);
+
+ // Check for any CUDA errors
+ checkCUDAError("memcpy");
+
+ // verify the data returned to the host is correct
+ for (int i = 0; i < dimA; i++) {
+ assert(h_a[i] == dimA - 1 - i);
+ }
+ // free device memory
+ cudaFree(d_a);
+ cudaFree(d_b);
+
+ // 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(EXIT_FAILURE);
+ }
+}
--- /dev/null
+/*
+ * 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 <stdio.h>
+#include <assert.h>
+
+// Simple utility function to check for CUDA runtime errors
+void checkCUDAError(const char *msg);
+
+// Part 1 of 1: implement the kernel
+__global__ void reverseArrayBlock(int *d_out, int *d_in)
+{
+ int in = threadIdx.x;
+ int out = blockDim.x - 1 - threadIdx.x;
+ d_out[out] = d_in[in];
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// Program main
+////////////////////////////////////////////////////////////////////////////////
+int main(int argc, char **argv)
+{
+
+ // pointer for host memory and size
+ int *h_a;
+ int dimA = 256;
+
+ // pointer for device memory
+ int *d_b, *d_a;
+
+ // define grid and block size
+ int numBlocks = 1;
+ int numThreadsPerBlock = dimA;
+
+ // allocate host and device memory
+ size_t memSize = numBlocks * numThreadsPerBlock * sizeof(int);
+ h_a = (int *)malloc(memSize);
+ cudaMalloc((void **)&d_a, memSize);
+ cudaMalloc((void **)&d_b, memSize);
+
+ // Initialize input array on host
+ for (int i = 0; i < dimA; ++i) {
+ h_a[i] = i;
+ }
+ // Copy host array to device array
+ cudaMemcpy(d_a, h_a, memSize, cudaMemcpyHostToDevice);
+
+ // launch kernel
+ dim3 dimGrid(numBlocks);
+ dim3 dimBlock(numThreadsPerBlock);
+ reverseArrayBlock <<< dimGrid, dimBlock >>> (d_b, d_a);
+
+ // block until the device has completed
+ cudaThreadSynchronize();
+
+ // check if kernel execution generated an error
+ // Check for any CUDA errors
+ checkCUDAError("kernel invocation");
+
+ // device to host copy
+ cudaMemcpy(h_a, d_b, memSize, cudaMemcpyDeviceToHost);
+
+ // Check for any CUDA errors
+ checkCUDAError("memcpy");
+
+ // verify the data returned to the host is correct
+ for (int i = 0; i < dimA; i++) {
+ assert(h_a[i] == dimA - 1 - i);
+ }
+ // free device memory
+ cudaFree(d_a);
+ cudaFree(d_b);
+
+ // 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(EXIT_FAILURE);
+ }
+}
projects / parallel_computing.git / commitdiff