1 /* Copyright 2015 The TensorFlow Authors. All Rights Reserved. 2 3 Licensed under the Apache License, Version 2.0 (the "License"); 4 you may not use this file except in compliance with the License. 5 You may obtain a copy of the License at 6 7 http://www.apache.org/licenses/LICENSE-2.0 8 9 Unless required by applicable law or agreed to in writing, software 10 distributed under the License is distributed on an "AS IS" BASIS, 11 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 See the License for the specific language governing permissions and 13 limitations under the License. 14 ==============================================================================*/ 15 16 #ifndef TENSORFLOW_FRAMEWORK_RESOURCE_HANDLE_H_ 17 #define TENSORFLOW_FRAMEWORK_RESOURCE_HANDLE_H_ 18 19 #include <string> 20 21 #include "tensorflow/core/framework/resource_base.h" 22 #include "tensorflow/core/framework/tensor_shape.h" 23 #include "tensorflow/core/framework/type_index.h" 24 #include "tensorflow/core/framework/types.pb.h" 25 #include "tensorflow/core/platform/casts.h" 26 #include "tensorflow/core/platform/intrusive_ptr.h" 27 #include "tensorflow/core/platform/statusor.h" 28 #include "tensorflow/core/platform/tensor_coding.h" 29 #include "tensorflow/core/platform/types.h" 30 #include "tensorflow/core/util/managed_stack_trace.h" 31 32 namespace tensorflow { 33 34 class ResourceHandleProto; 35 36 // Class representing a handle to a tensorflow resource. Handles are 37 // not valid across executions, but can be serialized back and forth from within 38 // a single run (except for those created from MakeRefCountingHandle i.e. whose 39 // resource_ field is not empty). 40 // 41 // This is the native C++ class equivalent of ResourceHandleProto. They are 42 // separate so that kernels do not need to depend on protos. 43 class ResourceHandle { 44 public: 45 ResourceHandle(); 46 ResourceHandle(const ResourceHandleProto& proto); 47 ~ResourceHandle(); 48 49 // Use this factory method if the `proto` comes from user controlled input, to 50 // prevent a denial of service. 51 static Status BuildResourceHandle(const ResourceHandleProto& proto, 52 ResourceHandle* out); 53 54 // Unique name for the device containing the resource. device()55 const std::string& device() const { return device_; } 56 set_device(const std::string & device)57 void set_device(const std::string& device) { device_ = device; } 58 59 // Container in which this resource is placed. container()60 const std::string& container() const { return container_; } set_container(const std::string & container)61 void set_container(const std::string& container) { container_ = container; } 62 63 // Unique name of this resource. name()64 const std::string& name() const { return name_; } set_name(const std::string & name)65 void set_name(const std::string& name) { name_ = name; } 66 67 // Hash code for the type of the resource. Is only valid in the same device 68 // and in the same execution. hash_code()69 uint64 hash_code() const { return hash_code_; } set_hash_code(uint64 hash_code)70 void set_hash_code(uint64 hash_code) { hash_code_ = hash_code; } 71 72 // For debug-only, the name of the type pointed to by this handle, if 73 // available. maybe_type_name()74 const std::string& maybe_type_name() const { return maybe_type_name_; } set_maybe_type_name(const std::string & value)75 void set_maybe_type_name(const std::string& value) { 76 maybe_type_name_ = value; 77 } 78 79 // Data types and shapes for the underlying resource. dtypes_and_shapes()80 std::vector<DtypeAndPartialTensorShape> dtypes_and_shapes() const { 81 return dtypes_and_shapes_; 82 } set_dtypes_and_shapes(const std::vector<DtypeAndPartialTensorShape> & dtypes_and_shapes)83 void set_dtypes_and_shapes( 84 const std::vector<DtypeAndPartialTensorShape>& dtypes_and_shapes) { 85 dtypes_and_shapes_ = dtypes_and_shapes; 86 } 87 set_definition_stack_trace(const absl::optional<ManagedStackTrace> & definition_stack_trace)88 void set_definition_stack_trace( 89 const absl::optional<ManagedStackTrace>& definition_stack_trace) { 90 definition_stack_trace_ = definition_stack_trace; 91 } 92 definition_stack_trace()93 const absl::optional<ManagedStackTrace>& definition_stack_trace() const { 94 return definition_stack_trace_; 95 } 96 97 // Conversion to and from ResourceHandleProto 98 void AsProto(ResourceHandleProto* proto) const; 99 Status FromProto(const ResourceHandleProto& proto); 100 101 // Serialization via ResourceHandleProto 102 std::string SerializeAsString() const; 103 bool ParseFromString(const std::string& s); 104 105 std::string DebugString() const; 106 107 std::string SummarizeValue() const; 108 109 // GUID for anonymous resources. Resources with this shared_name will have 110 // their shared_name replaced with a GUID at creation time 111 static constexpr const char* ANONYMOUS_NAME = 112 "cd2c89b7-88b7-44c8-ad83-06c2a9158347"; 113 114 // Creates a `ResourceHandle` that holds a pointer to a resource and takes 115 // ownership of it. Normally a `ResourceHandle` only contains the name (and 116 // some other metadata) of the resource. When created via this function, 117 // the handle will own the resource, in the sense that it will destroy the 118 // resource automatically when the resource is no longer needed. It does this 119 // via automatic ref-counting on the resource: when the handle is copied, it 120 // will call `Ref` on the resource (remember that all resources inherit from 121 // `ResourceBase` which inherits from `RefCounted`), and when the handle is 122 // destroyed, it will call `Unref` on the resource. When the last handle goes 123 // out of scope, the resource's ref-count will go down to zero and the 124 // resource will be destroyed. When calling this function, the `resource` 125 // argument should have a ref-count of one (which is the case when the 126 // resource is newly created). 127 // 128 // For those familiar with `ResourceMgr`, when you create a handle by the 129 // `MakeResourceHandle` function in resource_mgr.h, the handle doesn't hold a 130 // strong reference to the resource, and the resource is owned by the 131 // resource manager whose strong reference must be manually deleted by 132 // calling `ResourceMgr::Delete`. In contrast, a handle created by this 133 // function holds a strong reference to the resource. The resource manager 134 // does not hold a strong reference to the resource. 135 template <typename T> 136 static ResourceHandle MakeRefCountingHandle( 137 T* resource, const string& device_name, 138 const std::vector<DtypeAndPartialTensorShape>& dtypes_and_shapes = {}, 139 const absl::optional<ManagedStackTrace>& definition_stack_trace = {}) { 140 return MakeRefCountingHandle(resource, device_name, TypeIndex::Make<T>(), 141 dtypes_and_shapes, definition_stack_trace); 142 } 143 144 static ResourceHandle MakeRefCountingHandle( 145 ResourceBase* resource, const string& device_name, 146 const TypeIndex& type_index, 147 const std::vector<DtypeAndPartialTensorShape>& dtypes_and_shapes = {}, 148 const absl::optional<ManagedStackTrace>& definition_stack_trace = {}); 149 150 // Pointer to the resource. resource()151 const core::IntrusivePtr<ResourceBase>& resource() const { return resource_; } 152 153 // Gets the resource pointer in `handle` as `T*`, or an error if the actual 154 // resource type is not `T`. 155 template <typename T> GetResource()156 StatusOr<T*> GetResource() const { 157 TF_RETURN_IF_ERROR(ValidateType<T>()); 158 return down_cast<T*>(resource_.get()); 159 } 160 161 // Returns True if the resource handle is ref-counting. 162 // See MakeRefCountingHandle. IsRefCounting()163 bool IsRefCounting() const { return resource_.get() != nullptr; } 164 165 // Validates that the resource type in `handle` is `T`. 166 template <typename T> ValidateType()167 Status ValidateType() const { 168 return ValidateType(TypeIndex::Make<T>()); 169 } 170 171 Status ValidateType(const TypeIndex& type_index) const; 172 173 // Generates unique IDs (e.g. for names of anonymous variables) 174 static int64_t GenerateUniqueId(); 175 176 private: 177 std::string device_; 178 std::string container_; 179 std::string name_; 180 uint64 hash_code_ = 0; 181 std::string maybe_type_name_; 182 std::vector<DtypeAndPartialTensorShape> dtypes_and_shapes_; 183 absl::optional<ManagedStackTrace> definition_stack_trace_; 184 // A smart pointer to the actual resource. When this field is not empty, the 185 // handle is in a "ref-counting" mode, owning the resource; otherwise it's in 186 // a "weak-ref" mode, only containing the name of the resource (conceptually a 187 // weak reference). 188 core::IntrusivePtr<ResourceBase> resource_; 189 static std::atomic<int64_t> current_id_; 190 }; 191 192 // For backwards compatibility for when this was a proto 193 std::string ProtoDebugString(const ResourceHandle& handle); 194 195 // Encodes a list of ResourceHandle protos in the given StringListEncoder. 196 void EncodeResourceHandleList(const ResourceHandle* p, int64_t n, 197 std::unique_ptr<port::StringListEncoder> e); 198 199 // Decodes a list of ResourceHandle protos from the given StringListDecoder. 200 bool DecodeResourceHandleList(std::unique_ptr<port::StringListDecoder> d, 201 ResourceHandle* ps, int64_t n); 202 203 } // namespace tensorflow 204 205 #endif // TENSORFLOW_FRAMEWORK_RESOURCE_HANDLE_H_ 206