File size: 5,544 Bytes
9375c9a
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
// Copyright (C) 2015  Davis E. King (davis@dlib.net)
// License: Boost Software License   See LICENSE.txt for the full license.
#ifndef DLIB_DNN_CuBLAS_CPP_
#define DLIB_DNN_CuBLAS_CPP_

#ifdef DLIB_USE_CUDA

#include "cublas_dlibapi.h"
#include "cuda_utils.h"

#include <cublas_v2.h>
#include <vector>

static const char* cublas_get_error_string(cublasStatus_t s)
{
    switch(s)
    {
        case CUBLAS_STATUS_NOT_INITIALIZED: 
            return "CUDA Runtime API initialization failed.";
        case CUBLAS_STATUS_ALLOC_FAILED: 
            return "CUDA Resources could not be allocated.";
        default:
            return "A call to cuBLAS failed";
    }
}

// Check the return value of a call to the cuBLAS runtime for an error condition.
#define CHECK_CUBLAS(call)                                                      \
do{                                                                              \
    const cublasStatus_t error = call;                                         \
    if (error != CUBLAS_STATUS_SUCCESS)                                        \
    {                                                                          \
        std::ostringstream sout;                                               \
        sout << "Error while calling " << #call << " in file " << __FILE__ << ":" << __LINE__ << ". ";\
        sout << "code: " << error << ", reason: " << cublas_get_error_string(error);\
        throw dlib::cublas_error(sout.str());                            \
    }                                                                          \
}while(false)

namespace dlib
{
    namespace cuda 
    {

    // -----------------------------------------------------------------------------------

        class cublas_context
        {
        public:
            // not copyable
            cublas_context(const cublas_context&) = delete;
            cublas_context& operator=(const cublas_context&) = delete;

            cublas_context()
            {
                handles.resize(16);
            }
            ~cublas_context()
            {
                for (auto h : handles)
                {
                    if (h)
                        cublasDestroy(h);
                }
            }

            cublasHandle_t get_handle (
            )  
            { 
                int new_device_id;
                CHECK_CUDA(cudaGetDevice(&new_device_id));
                // make room for more devices if needed
                if (new_device_id >= (long)handles.size())
                    handles.resize(new_device_id+16);

                // If we don't have a handle already for this device then make one
                if (!handles[new_device_id])
                    CHECK_CUBLAS(cublasCreate(&handles[new_device_id]));

                // Finally, return the handle for the current device
                return handles[new_device_id];
            }

        private:

            std::vector<cublasHandle_t> handles;
        };

        static cublasHandle_t context()
        {
            thread_local cublas_context c;
            return c.get_handle();
        }

    // -----------------------------------------------------------------------------------

        void gemm (
            float beta,
            tensor& dest,
            float alpha,
            const tensor& lhs,
            bool trans_lhs,
            const tensor& rhs,
            bool trans_rhs
        )
        {
            // Recall that BLAS uses column major order so to deal with that we flip the
            // order of the lhs and rhs arguments.
            const auto transa = trans_lhs ? CUBLAS_OP_T : CUBLAS_OP_N;
            const auto transb = trans_rhs ? CUBLAS_OP_T : CUBLAS_OP_N;

            const int dest_nr = dest.num_samples();
            const int dest_nc = dest.size()/dest_nr;
            const int lhs_nr = lhs.num_samples();
            const int lhs_nc = lhs.size()/lhs_nr;
            const int rhs_nr = rhs.num_samples();
            const int rhs_nc = rhs.size()/rhs_nr;
            if (trans_lhs && trans_rhs)
            {
                DLIB_ASSERT( dest_nr == lhs_nc &&
                              dest_nc == rhs_nr &&
                              lhs_nr == rhs_nc)
            }
            else if (!trans_lhs && trans_rhs)
            {
                DLIB_ASSERT( dest_nr == lhs_nr &&
                              dest_nc == rhs_nr &&
                              lhs_nc == rhs_nc)
            }
            else if (trans_lhs && !trans_rhs)
            {
                DLIB_ASSERT( dest_nr == lhs_nc &&
                              dest_nc == rhs_nc &&
                              lhs_nr == rhs_nr)
            }
            else
            {
                DLIB_ASSERT( dest_nr == lhs_nr &&
                              dest_nc == rhs_nc &&
                              lhs_nc == rhs_nr)
            }

            const int k = trans_rhs ? rhs_nc : rhs_nr;
            CHECK_CUBLAS(cublasSgemm(context(),
                              transb,
                              transa, 
                              dest_nc, dest_nr, k,
                              &alpha,
                              rhs.device(), rhs_nc,
                              lhs.device(), lhs_nc,
                              &beta,
                              dest.device(),dest_nc));
        }

    // ------------------------------------------------------------------------------------

    }  
}

#endif // DLIB_USE_CUDA

#endif // DLIB_DNN_CuBLAS_CPP_