aboutsummaryrefslogtreecommitdiff
path: root/src/cpu/utils/CpuAuxTensorHandler.h
blob: 3b980ce60b53b30eab7434c24ac094b3ff1f5357 (plain)
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
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
/*
 * Copyright (c) 2021, 2023-2024 Arm Limited.
 *
 * SPDX-License-Identifier: MIT
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
#ifndef ACL_SRC_CPU_UTILS_CPUAUXTENSORHANDLER_H
#define ACL_SRC_CPU_UTILS_CPUAUXTENSORHANDLER_H

#include "arm_compute/core/ITensorPack.h"
#include "arm_compute/core/TensorInfo.h"
#include "arm_compute/runtime/Tensor.h"

#include "src/common/utils/Log.h"
#include "support/Cast.h"

namespace arm_compute
{
namespace cpu
{
/** Tensor handler to wrap and handle tensor allocations on workspace buffers
 *
 * @note Important: Despite the impression given by its name, the handler owns, rather than merely points to, the
 *       underlying tensor memory.
 *
 * @note About memory handling using bypass_* flags
 * The bypass_alloc / bypass_import flags are meant to skip the expensive auxiliary tensor memory allocations or
 * imports that are not needed during runtime, e.g. when the handler is not used at all in some branch of execution.
 *
 * If not handled correctly, these two flags can lead to performance issues (not bypass when needed to), or memory
 * bugs (bypass when should not to).
 *
 * Make sure:
 *
 * 1. The aux tensor handlers must always be declared at the root level, or the same level as the run/prepare
 *    methods that potentially use them.
 *
 *    Once the handler is destroyed (e.g. when going out of scope), the memory it owns (returned by the get()
 *    method) will also be destroyed.
 *
 *    Thus it's important to ensure the handler is always in-scope when it is being used by a operator / kernel.
 *
 * 2. The handler's bypass_alloc and bypass_import flags should always be inverse of whether the handler is used in
 *    its surrounding scope by run/prepare. (This usually means being added to some tensor pack)
 *
 *    This ensures we only bypass if and only if the aux tensor is not used by the op / kernel later.
 *
 *
 * So the general usage pattern goes like this:
 *
 *      bool use_aux_tensor =  some_condition_about_when_to_use_the_aux_tensor
 *
 *      CpuAuxTensorHandler aux_handler {..., !use_aux_tensor || bypass_alloc / bypass_import ||};
 *
 *      if (use_aux_tensor)
 *      {
 *          tensor_pack.add_tensor(aux_handler.get());
 *      }
 *      op.run(tensor_pack);
 */
class CpuAuxTensorHandler
{
public:
    /** Create a temporary tensor handle, by either important an existing tensor from a tensor pack, or allocating a
     *  new one.
     *
     * @param[in]     slot_id       Slot id of the tensor to be retrieved in the tensor pack
     *                              If no such tensor exists in the tensor pack, a new tensor will be allocated.
     * @param[in]     info          Tensor info containing requested size of the new tensor.
     *                              If requested size is larger than the tensor retrieved from the tensor pack,
     *                              a new tensor will be allocated.
     * @param[in,out] pack          Tensor pack to retrieve the old tensor. When @p pack_inject is true, the new
     *                              tensor will also be added here.
     * @param[in]     pack_inject   In case of a newly allocated tensor, whether to add this tensor back to the
     *                              @p pack
     * @param[in]     bypass_alloc  Bypass allocation in case of a new tensor
     *                              This is to prevent unnecessary memory operations when the handler object is not
     *                              used
     * @param[in]     bypass_import Bypass importation in case of a retrieved tensor
     *                                  This is to prevent unnecessary memory operations when the handler object is not
     *                                  used
     */
    CpuAuxTensorHandler(int          slot_id,
                        TensorInfo  &info,
                        ITensorPack &pack,
                        bool         pack_inject   = false,
                        bool         bypass_alloc  = false,
                        bool         bypass_import = false)
        : _tensor()
    {
        if (info.total_size() == 0)
        {
            return;
        }
        _tensor.allocator()->soft_init(info);

        ITensor *packed_tensor = utils::cast::polymorphic_downcast<ITensor *>(pack.get_tensor(slot_id));
        if ((packed_tensor == nullptr) || (info.total_size() > packed_tensor->info()->total_size()))
        {
            if (!bypass_alloc)
            {
                _tensor.allocator()->allocate();
                ARM_COMPUTE_LOG_INFO_WITH_FUNCNAME_ACL("Allocating auxiliary tensor");
            }

            if (pack_inject)
            {
                pack.add_tensor(slot_id, &_tensor);
                _injected_tensor_pack = &pack;
                _injected_slot_id     = slot_id;
            }
        }
        else
        {
            if (!bypass_import)
            {
                _tensor.allocator()->import_memory(packed_tensor->buffer());
            }
        }
    }

    /** Create a temporary handle to the original tensor with a new @ref TensorInfo
     * This is useful if we want to change a tensor's tensor info at run time without modifying the original tensor
     *
     * @param[in] info          New tensor info to "assign" to @p tensor
     * @param[in] tensor        Tensor to be assigned a new @ref TensorInfo
     * @param[in] bypass_import Bypass importing @p tensor's memory into the handler.
     *                          This is to prevent unnecessary memory operations when the handler object is not used
     */
    CpuAuxTensorHandler(TensorInfo &info, const ITensor &tensor, bool bypass_import = false) : _tensor()
    {
        _tensor.allocator()->soft_init(info);
        if (!bypass_import)
        {
            ARM_COMPUTE_ERROR_ON(tensor.info() == nullptr);
            if (info.total_size() <= tensor.info()->total_size())
            {
                _tensor.allocator()->import_memory(tensor.buffer());
            }
        }
    }

    CpuAuxTensorHandler(const CpuAuxTensorHandler &)          = delete;
    CpuAuxTensorHandler &operator=(const CpuAuxTensorHandler) = delete;

    ~CpuAuxTensorHandler()
    {
        if (_injected_tensor_pack)
        {
            _injected_tensor_pack->remove_tensor(_injected_slot_id);
        }
    }

    ITensor *get()
    {
        return &_tensor;
    }

    ITensor *operator()()
    {
        return &_tensor;
    }

private:
    Tensor       _tensor{};
    ITensorPack *_injected_tensor_pack{nullptr};
    int          _injected_slot_id{TensorType::ACL_UNKNOWN};
};
} // namespace cpu
} // namespace arm_compute
#endif // ACL_SRC_CPU_UTILS_CPUAUXTENSORHANDLER_H