refine nlp multi-threads

paddle/fluid/inference/tests/book/test_inference_nlp.cc

@@ -101,23 +101,22 @@ void SplitData(
 }
 
 void ThreadRunInfer(
-    const int tid, paddle::framework::Executor* executor,
-    paddle::framework::Scope* scope,
-    const std::unique_ptr<paddle::framework::ProgramDesc>& inference_program,
+    const int tid, paddle::framework::Scope* scope,
     const std::vector<std::vector<const paddle::framework::LoDTensor*>>& jobs) {
-  auto copy_program = std::unique_ptr<paddle::framework::ProgramDesc>(
-      new paddle::framework::ProgramDesc(*inference_program));
+  // maybe framework:ProgramDesc is not thread-safe
   auto& sub_scope = scope->NewScope();
+  auto place = paddle::platform::CPUPlace();
+  auto executor = paddle::framework::Executor(place);
+  auto inference_program =
+      paddle::inference::Load(&executor, scope, FLAGS_model_path);
 
-  std::string feed_holder_name = "feed_" + paddle::string::to_string(tid);
-  std::string fetch_holder_name = "fetch_" + paddle::string::to_string(tid);
-  copy_program->SetFeedHolderName(feed_holder_name);
-  copy_program->SetFetchHolderName(fetch_holder_name);
+  auto ctx = executor.Prepare(*inference_program, /*block_id*/ 0);
+  executor.CreateVariables(*inference_program, &sub_scope, /*block_id*/ 0);
 
   const std::vector<std::string>& feed_target_names =
-      copy_program->GetFeedTargetNames();
+      inference_program->GetFeedTargetNames();
   const std::vector<std::string>& fetch_target_names =
-      copy_program->GetFetchTargetNames();
+      inference_program->GetFetchTargetNames();
 
   PADDLE_ENFORCE_EQ(fetch_target_names.size(), 1UL);
   std::map<std::string, paddle::framework::LoDTensor*> fetch_targets;
@@ -131,9 +130,8 @@ void ThreadRunInfer(
   auto start_ms = GetCurrentMs();
   for (size_t i = 0; i < inputs.size(); ++i) {
     feed_targets[feed_target_names[0]] = inputs[i];
-    executor->Run(*copy_program, &sub_scope, &feed_targets, &fetch_targets,
-                  true /*create_local_scope*/, true /*create_vars*/,
-                  feed_holder_name, fetch_holder_name);
+    executor.RunPreparedContext(ctx.get(), &sub_scope, &feed_targets,
+                                &fetch_targets, false /*create_local_scope*/);
   }
   auto stop_ms = GetCurrentMs();
   scope->DeleteScope(&sub_scope);
@@ -158,22 +156,10 @@ TEST(inference, nlp) {
   LOG(INFO) << "Number of samples (seq_len<1024): " << datasets.size();
   LOG(INFO) << "Total number of words: " << num_total_words;
 
-  const bool model_combined = false;
   // 0. Call `paddle::framework::InitDevices()` initialize all the devices
-  // 1. Define place, executor, scope
-  auto place = paddle::platform::CPUPlace();
-  auto executor = paddle::framework::Executor(place);
   std::unique_ptr<paddle::framework::Scope> scope(
       new paddle::framework::Scope());
 
-  // 2. Initialize the inference_program and load parameters
-  std::unique_ptr<paddle::framework::ProgramDesc> inference_program;
-  inference_program =
-      InitProgram(&executor, scope.get(), FLAGS_model_path, model_combined);
-  if (FLAGS_use_mkldnn) {
-    EnableMKLDNN(inference_program);
-  }
-
 #ifdef PADDLE_WITH_MKLML
   // only use 1 thread number per std::thread
   omp_set_dynamic(0);
@@ -189,21 +175,30 @@ TEST(inference, nlp) {
     start_ms = GetCurrentMs();
     for (int i = 0; i < FLAGS_num_threads; ++i) {
       threads.emplace_back(
-          new std::thread(ThreadRunInfer, i, &executor, scope.get(),
-                          std::ref(inference_program), std::ref(jobs)));
+          new std::thread(ThreadRunInfer, i, scope.get(), std::ref(jobs)));
     }
     for (int i = 0; i < FLAGS_num_threads; ++i) {
       threads[i]->join();
     }
     stop_ms = GetCurrentMs();
   } else {
-    if (FLAGS_prepare_vars) {
-      executor.CreateVariables(*inference_program, scope.get(), 0);
+    // 1. Define place, executor, scope
+    auto place = paddle::platform::CPUPlace();
+    auto executor = paddle::framework::Executor(place);
+
+    // 2. Initialize the inference_program and load parameters
+    std::unique_ptr<paddle::framework::ProgramDesc> inference_program;
+    inference_program = InitProgram(&executor, scope.get(), FLAGS_model_path,
+                                    /*model combined*/ false);
+    if (FLAGS_use_mkldnn) {
+      EnableMKLDNN(inference_program);
     }
     // always prepare context
     std::unique_ptr<paddle::framework::ExecutorPrepareContext> ctx;
     ctx = executor.Prepare(*inference_program, 0);
-
+    if (FLAGS_prepare_vars) {
+      executor.CreateVariables(*inference_program, scope.get(), 0);
+    }
     // preapre fetch
     const std::vector<std::string>& fetch_target_names =
         inference_program->GetFetchTargetNames();