1 /* Copyright 2017 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_CORE_GRAPPLER_OPTIMIZERS_META_OPTIMIZER_H_ 17 #define TENSORFLOW_CORE_GRAPPLER_OPTIMIZERS_META_OPTIMIZER_H_ 18 19 #include "tensorflow/core/common_runtime/device_set.h" 20 #include "tensorflow/core/framework/device_base.h" 21 #include "tensorflow/core/framework/function.h" 22 #include "tensorflow/core/graph/graph.h" 23 #include "tensorflow/core/grappler/grappler_item.h" 24 #include "tensorflow/core/grappler/optimizers/graph_optimizer.h" 25 #include "tensorflow/core/grappler/verifiers/graph_verifier.h" 26 #include "tensorflow/core/lib/core/status.h" 27 #include "tensorflow/core/protobuf/config.pb.h" 28 #include "tensorflow/core/protobuf/rewriter_config.pb.h" 29 #include "tensorflow/core/protobuf/verifier_config.pb.h" 30 31 namespace tensorflow { 32 namespace grappler { 33 34 // Run the other grappler optimizers based on the specified rewriter config. 35 class MetaOptimizer : public GraphOptimizer { 36 public: 37 MetaOptimizer(DeviceBase* cpu_device, const ConfigProto& cfg); 38 ~MetaOptimizer() override = default; 39 name()40 string name() const override { return "meta_optimizer"; }; 41 UsesFunctionLibrary()42 bool UsesFunctionLibrary() const override { return true; } 43 Optimize(Cluster * cluster,const GrapplerItem & item,GraphDef * optimized_graph)44 Status Optimize(Cluster* cluster, const GrapplerItem& item, 45 GraphDef* optimized_graph) override { 46 GrapplerItem copy(item); 47 return OptimizeConsumeItem(cluster, std::move(copy), optimized_graph); 48 } 49 50 Status OptimizeConsumeItem(Cluster* cluster, GrapplerItem&& item, 51 GraphDef* optimized_graph); 52 53 string GetResultString() const; 54 55 void PrintResult(); 56 57 private: 58 std::unique_ptr<GraphOptimizer> MakeNewOptimizer( 59 const string& optimizer, const std::set<string>& device_types) const; 60 61 // When grappler should lower control flow to V1 switch/merge style nodes. 62 bool LowerControlFlow() const; 63 64 // Initialize active optimizers from RewriterConfig toggles. 65 Status InitializeOptimizers( 66 const std::set<string>& device_types, 67 std::vector<std::unique_ptr<GraphOptimizer>>* optimizers) const; 68 // Initialize active optimizers from RewriterConfig optimizer names. 69 Status InitializeOptimizersByName( 70 const std::set<string>& device_types, 71 std::vector<std::unique_ptr<GraphOptimizer>>* optimizers) const; 72 // Initialize active optimizers from RewriterConfig.custom_optimizers. 73 Status InitializeCustomGraphOptimizers( 74 const std::set<string>& device_types, 75 const std::set<string>& pre_initialized_optimizers, 76 std::vector<std::unique_ptr<GraphOptimizer>>* optimizers) const; 77 Status InitializePluginGraphOptimizers( 78 const std::set<string>& device_types, 79 std::vector<std::unique_ptr<GraphOptimizer>>* optimizers) const; 80 // Returns the config for a custom graph optimizer. Null if none was found. 81 const RewriterConfig::CustomGraphOptimizer* GetCustomGraphOptimizerConfig( 82 const string& name) const; 83 84 // Initialize active verifiers from the RewriterConfig toggles. 85 void InitializeVerifiers( 86 std::vector<std::unique_ptr<GraphVerifier>>* inter_optimizer_verifiers, 87 std::vector<std::unique_ptr<GraphVerifier>>* post_optimization_verifiers) 88 const; 89 90 void PrintUserAndPluginConfigs(const std::set<string>& device_types) const; 91 92 // Run optimization pass over a single GrapplerItem. Meta optimizer might run 93 // multiple such passes: 1) for the main graph 2) for the function library 94 Status OptimizeGraph( 95 const std::vector<std::unique_ptr<GraphOptimizer>>& optimizers, 96 Cluster* cluster, GrapplerItem&& item, GraphDef* optimized_graph); 97 Status OptimizeGraph(Cluster* cluster, GrapplerItem&& item, 98 GraphDef* optimized_graph); 99 100 DeviceBase* const cpu_device_; // may be NULL 101 ConfigProto config_proto_; 102 RewriterConfig& cfg_; 103 bool xla_auto_clustering_on_; 104 105 struct OptimizerResult { 106 string optimizer_name; 107 string message; 108 Status status; 109 }; 110 111 struct GraphOptimizationResult { GraphOptimizationResultGraphOptimizationResult112 explicit GraphOptimizationResult(const string& id) : id(id) {} 113 string id; 114 std::vector<OptimizerResult> results; 115 }; 116 117 Status RunOptimizer(GraphOptimizer* optimizer, Cluster* cluster, 118 GrapplerItem* optimized_item, GraphDef* optimized_graph, 119 GraphOptimizationResult* optimization_result); 120 121 std::vector<GraphOptimizationResult> optimization_results_; 122 }; 123 124 bool MetaOptimizerEnabled(const ConfigProto& cfg); 125 126 // Run the meta optimizer. 127 // 128 // If <cpu_device> is non-null, it is the device to be used for executing ops 129 // during constant folding; if NULL, a new device is created for doing constant 130 // folding. For performance, it is recommended to pass in an existing cpu_device 131 // when possible. 132 Status RunMetaOptimizer(GrapplerItem&& item, const ConfigProto& cfg, 133 DeviceBase* cpu_device, Cluster* cluster, 134 GraphDef* optimized_graph); 135 136 // Wrapper around RunMetaOptimizer convenient for optimizing 137 // function graphs. 138 // 139 // Runs grappler optimizations on `g` based on `config_proto`. 140 // `ret_node_names`: a vector of node names whose outputs are returned, 141 // aka fetches. when `g` represent a function, these are _Retval nodes. 142 // `lib`: function library to use with `g`. 143 // `device_set`: the set of devices that graph can refer to. 144 // `cpu_device`: the CPU device. 145 // `config_proto`: Grapper configuration. 146 // `grappler_item_id': Grappler item id (e.g. optimized function name). 147 // `optimization_options`: Grappler optimization constraints that are known only 148 // at runtime. 149 // 150 // **g is a graph constructed based on the runtime library 'lib'. 151 // OptimizeGraph mutates **g extensively and replaces '*g' with a 152 // complete copy. Therefore, the caller should not keep any references 153 // to nodes *g. 154 Status OptimizeGraph( 155 std::vector<string> ret_node_names, std::vector<string> keep_node_names, 156 FunctionLibraryDefinition* lib, const DeviceSet& device_set, 157 Device* cpu_device, const ConfigProto& config_proto, 158 const string& grappler_item_id, 159 const GrapplerItem::OptimizationOptions& optimization_options, 160 std::unique_ptr<tensorflow::Graph>* g); 161 162 } // namespace grappler 163 } // namespace tensorflow 164 165 #endif // TENSORFLOW_CORE_GRAPPLER_OPTIMIZERS_META_OPTIMIZER_H_ 166