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 42 Status Optimize(Cluster* cluster, const GrapplerItem& item, 43 GraphDef* optimized_graph) override; 44 45 void PrintResult(); 46 47 void Feedback(Cluster* cluster, const GrapplerItem& item, 48 const GraphDef& optimized_graph, double result) override; 49 50 private: 51 std::unique_ptr<GraphOptimizer> MakeNewOptimizer( 52 const string& optimizer) const; 53 54 // Initialize active optimizers from RewriterConfig toggles. 55 Status InitializeOptimizers( 56 std::vector<std::unique_ptr<GraphOptimizer>>* optimizers) const; 57 // Initialize active optimizers from RewriterConfig optimizer names. 58 Status InitializeOptimizersByName( 59 std::vector<std::unique_ptr<GraphOptimizer>>* optimizers) const; 60 // Initialize active optimizers from RewriterConfig.custom_optimizers. 61 Status InitializeCustomGraphOptimizers( 62 const std::set<string>& pre_initialized_optimizers, 63 std::vector<std::unique_ptr<GraphOptimizer>>* optimizers) const; 64 // Returns the config for a custom graph optimizer. Null if none was found. 65 const RewriterConfig::CustomGraphOptimizer* GetCustomGraphOptimizerConfig( 66 const string& name) const; 67 68 // Initialiaze active verifiers from the RewriterConfig toggles. 69 void InitializeVerifiers( 70 std::vector<std::unique_ptr<GraphVerifier>>* inter_optimizer_verifiers, 71 std::vector<std::unique_ptr<GraphVerifier>>* post_optimization_verifiers) 72 const; 73 74 // Run optimization pass over a single GrapplerItem. Meta optimizer might run 75 // multiple such passes: 1) for the main graph 2) for the function library 76 Status OptimizeGraph(Cluster* cluster, const GrapplerItem& item, 77 GraphDef* optimized_graph); 78 79 DeviceBase* const cpu_device_; // may be NULL 80 ConfigProto config_proto_; 81 RewriterConfig& cfg_; 82 83 struct OptimizerResult { 84 string optimizer_name; 85 string result; 86 }; 87 88 struct GraphOptimizationResult { GraphOptimizationResultGraphOptimizationResult89 explicit GraphOptimizationResult(const string& id) : id(id) {} 90 string id; 91 std::vector<OptimizerResult> results; 92 }; 93 94 Status RunOptimizer(GraphOptimizer* optimizer, Cluster* cluster, 95 GrapplerItem* optimized_item, GraphDef* optimized_graph, 96 GraphOptimizationResult* optimization_result); 97 98 std::vector<GraphOptimizationResult> optimization_results_; 99 }; 100 101 bool MetaOptimizerEnabled(const ConfigProto& cfg); 102 103 // Run the meta optimizer. 104 // 105 // If <cpu_device> is non-null, it is the device to be used for executing ops 106 // during constant folding; if NULL, a new device is created for doing constant 107 // folding. For performance, it is recommended to pass in an existing cpu_device 108 // when possible. 109 Status RunMetaOptimizer(const GrapplerItem& item, const ConfigProto& cfg, 110 DeviceBase* cpu_device, Cluster* cluster, 111 GraphDef* optimized_graph); 112 113 // Wrapper around RunMetaOptimizer convenient for optimizing 114 // function graphs. 115 // 116 // Runs grappler optimizations on `g` based on `config_proto`. 117 // `ret_node_names`: a vector of node names whose outputs are returned, 118 // aka fetches. when `g` represent a function, these are _Retval nodes. 119 // `lib`: function library to use with `g`. 120 // `device_set`: the set of devices that graph can refer to. 121 // `cpu_device`: the CPU device. 122 // `config_proto`: Grapper configuration. 123 // `grappler_item_id': Grappler item id (e.g. optimized function name). 124 // `optimization_options`: Grappler optimization constraints that are known only 125 // at runtime. 126 // 127 // **g is a graph constructed based on the runtime library 'lib'. 128 // OptimizeGraph mutates **g extensively and replaces '*g' with a 129 // complete copy. Therefore, the caller should not keep any references 130 // to nodes *g. 131 Status OptimizeGraph( 132 std::vector<string> ret_node_names, std::vector<string> keep_node_names, 133 FunctionLibraryDefinition* lib, const DeviceSet& device_set, 134 Device* cpu_device, const ConfigProto& config_proto, 135 const string& grappler_item_id, 136 const GrapplerItem::OptimizationOptions& optimization_options, 137 std::unique_ptr<tensorflow::Graph>* g); 138 139 } // namespace grappler 140 } // namespace tensorflow 141 142 #endif // TENSORFLOW_CORE_GRAPPLER_OPTIMIZERS_META_OPTIMIZER_H_ 143