X-Git-Url: http://git.tremily.us/?p=parallel_computing.git;a=blobdiff_plain;f=src%2Fcuda_by_example%2FcudaMallocAndMemcpy.cu;fp=src%2Fcuda_by_example%2FcudaMallocAndMemcpy.cu;h=50aac757d032ae6a0a5fbd53ab148831cd712204;hp=0000000000000000000000000000000000000000;hb=e696306bae683aebe418bf3de8fdeedf967ac4a7;hpb=647aaaa5dd881e31b0f79ffc21411e16d1a8ed34

diff --git a/src/cuda_by_example/cudaMallocAndMemcpy.cu b/src/cuda_by_example/cudaMallocAndMemcpy.cu
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+++ b/src/cuda_by_example/cudaMallocAndMemcpy.cu
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+/*
+ * 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);
+	}
+}