1/* Copyright 2018 The TensorFlow Authors. All Rights Reserved.
2
3Licensed under the Apache License, Version 2.0 (the "License");
4you may not use this file except in compliance with the License.
5You may obtain a copy of the License at
6
7 http://www.apache.org/licenses/LICENSE-2.0
8
9Unless required by applicable law or agreed to in writing, software
10distributed under the License is distributed on an "AS IS" BASIS,
11WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12See the License for the specific language governing permissions and
13limitations under the License.
14==============================================================================*/
15#ifndef TENSORFLOW_CORE_COMMON_RUNTIME_SCOPED_ALLOCATOR_MGR_H_
16#define TENSORFLOW_CORE_COMMON_RUNTIME_SCOPED_ALLOCATOR_MGR_H_
17
18#include <string>
19#include <unordered_map>
20
21#include "tensorflow/core/common_runtime/scoped_allocator.h"
22#include "tensorflow/core/lib/core/refcount.h"
23#include "tensorflow/core/lib/core/status.h"
24#include "tensorflow/core/platform/mutex.h"
25
26namespace tensorflow {
27class ScopedAllocatorMgr;
28
29// At most one of these exists per <device, step_id> pair.
30// A Ref is held by every ScopedAllocator and also by the ScopedAllocatorMgr.
31class ScopedAllocatorContainer : public core::RefCounted {
32 public:
33 // Establishes a reachable ScopedAllocator.
34 Status AddScopedAllocator(
35 const Tensor& backing_tensor, int32_t scope_id,
36 const std::string& scope_name,
37 const gtl::ArraySlice<ScopedAllocator::Field>& fields,
38 int32_t expected_call_count);
39
40 ScopedAllocatorInstance* GetInstance(int32_t scope_id);
41 ScopedAllocator* GetAllocator(int32_t scope_id);
42
43 // Retire the scope_id.
44 void Drop(int32_t scope_id, ScopedAllocator* sa);
45
46 protected:
47 friend class ScopedAllocatorMgr;
48 ScopedAllocatorContainer(const ScopedAllocatorMgr* mgr, int64_t step_id)
49 : mgr_(mgr), step_id_(step_id) {}
50 ~ScopedAllocatorContainer();
51
52 private:
53 const ScopedAllocatorMgr* mgr_;
54 int64_t step_id_;
55 mutex mu_;
56 struct SAField {
57 int32 field_index;
58 union {
59 ScopedAllocator* scoped_allocator;
60 ScopedAllocatorInstance* instance;
61 };
62 SAField(int32_t fi, ScopedAllocatorInstance* sai)
63 : field_index(fi), instance(sai) {}
64 SAField(int32_t fi, ScopedAllocator* sa)
65 : field_index(fi), scoped_allocator(sa) {}
66 SAField()
67 : field_index(ScopedAllocator::kBackingIndex),
68 scoped_allocator(nullptr) {}
69 };
70 std::unordered_map<int32, SAField> allocators_ TF_GUARDED_BY(mu_);
71};
72
73// At most one of these exists per device.
74class ScopedAllocatorMgr {
75 public:
76 explicit ScopedAllocatorMgr(const std::string& device_name)
77 : device_name_(device_name) {}
78 ~ScopedAllocatorMgr();
79
80 ScopedAllocatorContainer* GetContainer(int64_t step_id);
81
82 // Establishes a reachable ScopedAllocator.
83 Status AddScopedAllocator(
84 const Tensor& backing_tensor, int64_t step_id, int32_t scope_id,
85 const std::string& scope_name,
86 const gtl::ArraySlice<ScopedAllocator::Field>& fields,
87 int32_t expected_call_count);
88
89 void Cleanup(int64_t step_id);
90
91 // Populate the bytes and offset members of Field. Instance allocaters get
92 // consecutive scope_id values following that of the base ScopedAllocator.
93 // Returns the total number of bytes required to be allocated in the
94 // backing tensor, for convenience. (The same value can be obtained
95 // by summing offset and bytes in the last field.)
96 static size_t PopulateFields(int32_t scope_id,
97 const gtl::ArraySlice<TensorShape>& shapes,
98 const DataType dtype,
99 std::vector<ScopedAllocator::Field>* fields);
100
101 const std::string& device_name() const { return device_name_; }
102
103 private:
104 std::string device_name_;
105 mutex mu_;
106 std::unordered_map<int64_t, ScopedAllocatorContainer*> per_step_map_
107 TF_GUARDED_BY(mu_);
108};
109
110} // namespace tensorflow
111#endif // TENSORFLOW_CORE_COMMON_RUNTIME_SCOPED_ALLOCATOR_MGR_H_
112