finished multi_gpu sample

diff --git a/samples/gpu/multi_gpu.cpp b/samples/gpu/multi_gpu.cpp
index c569875..65562ee 100644 (file)
--- a/samples/gpu/multi_gpu.cpp
+++ b/samples/gpu/multi_gpu.cpp
@@ -31,18 +31,20 @@ using namespace std;
 using namespace cv;\r
 using namespace cv::gpu;\r
 \r
-\r
-void cuSafeCall(int code);\r
 struct Worker { void operator()(int device_id) const; };\r
-void destroy();\r
+void destroyContexts();\r
+\r
+#define cuSafeCall(code) if (code != CUDA_SUCCESS) { \\r
+    cout << "CUDA driver API error: code " << code \\r
+        << ", file " << __FILE__ << ", line " << __LINE__ << endl; \\r
+    destroyContexts(); \\r
+    exit(-1); \\r
+}\r
 \r
 \r
 // Each GPU is associated with its own context\r
 CUcontext contexts[2];\r
 \r
-// Auxiliary variable, stores previusly used context\r
-CUcontext prev_context;\r
-\r
 \r
 int main()\r
 {\r
@@ -52,50 +54,61 @@ int main()
         return -1;\r
     }\r
 \r
-    // Save the default context\r
-    cuSafeCall(cuCtxAttach(&contexts[0], 0));\r
-    cuSafeCall(cuCtxDetach(contexts[0]));\r
+    cuSafeCall(cuInit(0));\r
 \r
-    // Create new context for the second GPU\r
+    // Create context for the first GPU\r
     CUdevice device;\r
+    cuSafeCall(cuDeviceGet(&device, 0));\r
+    cuSafeCall(cuCtxCreate(&contexts[0], 0, device));\r
+\r
+    CUcontext prev_context;\r
+    cuCtxPopCurrent(&prev_context);\r
+\r
+    // Create context for the second GPU\r
     cuSafeCall(cuDeviceGet(&device, 1));\r
-    cuSafeCall(cuCtxCreate(&contexts[1], 0, device));\r
+    cuSafeCall(cuCtxCreate(&contexts[1], 1, device));\r
 \r
-    // Restore the first GPU context\r
-    cuSafeCall(cuCtxPopCurrent(&prev_context));\r
+    cuCtxPopCurrent(&prev_context);\r
 \r
-    // Run \r
+    // Execute calculation in two threads using two GPUs\r
     int devices[] = {0, 1};\r
     parallel_do(devices, devices + 2, Worker());\r
 \r
-    // Destroy context of the second GPU\r
-    destroy();\r
-\r
+    destroyContexts();\r
     return 0;\r
 }\r
 \r
 \r
 void Worker::operator()(int device_id) const\r
 {\r
-    cout << device_id << endl;\r
-}\r
+    cuCtxPushCurrent(contexts[device_id]);\r
 \r
+    // Generate random matrix\r
+    Mat src(1000, 1000, CV_32F);\r
+    RNG rng(0);\r
+    rng.fill(src, RNG::UNIFORM, 0, 1);\r
 \r
-void cuSafeCall(int code)\r
-{\r
-    if (code != CUDA_SUCCESS) \r
-    {\r
-        cout << "CUDA driver API error: code " << code \r
-            << ", file " << __FILE__ \r
-            << ", line " << __LINE__ << endl;\r
-        destroy();\r
-        exit(-1);\r
-    }\r
+    // Upload data on GPU\r
+    GpuMat d_src(src);\r
+    GpuMat d_dst;\r
+\r
+    transpose(d_src, d_dst);\r
+\r
+    // Deallocate here, otherwise deallocation will be performed \r
+    // after context is extracted from the stack\r
+    d_src.release();\r
+    d_dst.release();\r
+\r
+    CUcontext prev_context;\r
+    cuCtxPopCurrent(&prev_context);\r
+\r
+    cout << "Device " << device_id << " finished\n";\r
 }\r
 \r
 \r
-void destroy() \r
+void destroyContexts()\r
 {\r
+    cuCtxDestroy(contexts[0]);\r
     cuCtxDestroy(contexts[1]);\r
 }\r
 \r