1 /* ************************************************************************
2 * Copyright 2013 Advanced Micro Devices, Inc.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 * ************************************************************************/
16
17 #include <sys/types.h>
18 #include <stdio.h>
19 #include <string.h>
20 #include <math.h>
21
22 /* Include CLBLAS header. It automatically includes needed OpenCL header,
23 * so we can drop out explicit inclusion of cl.h header.
24 */
25 #include <clBLAS.h>
26
27 /* This example uses predefined matrices and their characteristics for
28 * simplicity purpose.
29 */
30 static const size_t N = 7;
31 static const cl_float alpha = 10;
32 static cl_float X[] = {
33 11,
34 21,
35 31,
36 41,
37 51,
38 61,
39 71,
40 };
41 static const int incx = 1;
42
43 static cl_float Y[] = {
44 15,
45 11,
46 1,
47 2,
48 1,
49 8,
50 1,
51 };
52 static const int incy = 1;
53
54
55 static void
printResult(void)56 printResult(void)
57 {
58 size_t i;
59 printf("\nResult:\n");
60
61 printf("Y\n");
62 for (i = 0; i < N; i++) {
63 printf("\t%f\n", Y[i]);
64 }
65 }
66
67 int
main(void)68 main(void)
69 {
70 cl_int err;
71 cl_platform_id platform = 0;
72 cl_device_id device = 0;
73 cl_context_properties props[3] = { CL_CONTEXT_PLATFORM, 0, 0 };
74 cl_context ctx = 0;
75 cl_command_queue queue = 0;
76 cl_mem bufX, bufY;
77 cl_event event = NULL;
78 int ret = 0;
79 int lenX = 1 + (N-1)*abs(incx);
80 int lenY = 1 + (N-1)*abs(incy);
81
82 /* Setup OpenCL environment. */
83 err = clGetPlatformIDs(1, &platform, NULL);
84 if (err != CL_SUCCESS) {
85 printf( "clGetPlatformIDs() failed with %d\n", err );
86 return 1;
87 }
88
89 err = clGetDeviceIDs(platform, CL_DEVICE_TYPE_GPU, 1, &device, NULL);
90 if (err != CL_SUCCESS) {
91 printf( "clGetDeviceIDs() failed with %d\n", err );
92 return 1;
93 }
94
95 props[1] = (cl_context_properties)platform;
96 ctx = clCreateContext(props, 1, &device, NULL, NULL, &err);
97 if (err != CL_SUCCESS) {
98 printf( "clCreateContext() failed with %d\n", err );
99 return 1;
100 }
101
102 queue = clCreateCommandQueue(ctx, device, 0, &err);
103 if (err != CL_SUCCESS) {
104 printf( "clCreateCommandQueue() failed with %d\n", err );
105 clReleaseContext(ctx);
106 return 1;
107 }
108
109 /* Setup clblas. */
110 err = clblasSetup();
111 if (err != CL_SUCCESS) {
112 printf("clblasSetup() failed with %d\n", err);
113 clReleaseCommandQueue(queue);
114 clReleaseContext(ctx);
115 return 1;
116 }
117
118 /* Prepare OpenCL memory objects and place matrices inside them. */
119 bufX = clCreateBuffer(ctx, CL_MEM_READ_ONLY, (lenX*sizeof(cl_float)), NULL, &err);
120 bufY = clCreateBuffer(ctx, CL_MEM_READ_WRITE, (lenY*sizeof(cl_float)), NULL, &err);
121
122 err = clEnqueueWriteBuffer(queue, bufX, CL_TRUE, 0, (lenX*sizeof(cl_float)), X, 0, NULL, NULL);
123 err = clEnqueueWriteBuffer(queue, bufY, CL_TRUE, 0, (lenY*sizeof(cl_float)), Y, 0, NULL, NULL);
124
125 /* Call clblas function. */
126 err = clblasSaxpy( N, alpha, bufX, 0, incx, bufY, 0, incy, 1, &queue, 0, NULL, &event);
127 if (err != CL_SUCCESS) {
128 printf("clblasSaxpy() failed with %d\n", err);
129 ret = 1;
130 }
131 else {
132 /* Wait for calculations to be finished. */
133 err = clWaitForEvents(1, &event);
134
135 /* Fetch results of calculations from GPU memory. */
136 err = clEnqueueReadBuffer(queue, bufY, CL_TRUE, 0, (lenY*sizeof(cl_float)),
137 Y, 0, NULL, NULL);
138
139 /* At this point you will get the result of SAXPY placed in vector Y. */
140 printResult();
141 }
142
143 /* Release OpenCL events. */
144 clReleaseEvent(event);
145
146 /* Release OpenCL memory objects. */
147 clReleaseMemObject(bufY);
148 clReleaseMemObject(bufX);
149
150 /* Finalize work with clblas. */
151 clblasTeardown();
152
153 /* Release OpenCL working objects. */
154 clReleaseCommandQueue(queue);
155 clReleaseContext(ctx);
156
157 return ret;
158 }
159