Add set_cpu_math_library_math_threads for CxxConfig (#2592)

* add set_cpu_math_library_math_threads for lite x86 platform, test=develop

* update the #if defined and add a condition LITE_WITH_X86, test=develop

* add if not defined LITE_ON_MODEL_OPTIMIZE_TOOL, test=develop

lite/api/CMakeLists.txt

@@ -18,6 +18,9 @@ if ((NOT LITE_ON_TINY_PUBLISH) AND (LITE_WITH_CUDA OR LITE_WITH_X86 OR ARM_TARGE
     if(LITE_WITH_X86)
         add_dependencies(paddle_full_api_shared xxhash)
         target_link_libraries(paddle_full_api_shared xxhash)
+        if (NOT LITE_ON_MODEL_OPTIMIZE_TOOL) 
+            add_dependencies(paddle_full_api_shared dynload_mklml)
+        endif()
     endif()
     if(LITE_WITH_CUDA)
         target_link_libraries(paddle_full_api_shared ${math_cuda} "-Wl,--whole-archive" ${cuda_kernels} "-Wl,--no-whole-archive")

lite/api/cxx_api_impl.cc

@@ -20,6 +20,12 @@
 #include "lite/core/device_info.h"
 #include "lite/core/version.h"
 
+#if (defined LITE_WITH_X86) && (defined PADDLE_WITH_MKLML) && \
+    !(defined LITE_ON_MODEL_OPTIMIZE_TOOL)
+#include <omp.h>
+#include "lite/backends/x86/mklml.h"
+#endif
+
 namespace paddle {
 namespace lite {
 
@@ -33,6 +39,17 @@ void CxxPaddleApiImpl::Init(const lite_api::CxxConfig &config) {
 
   mode_ = config.power_mode();
   threads_ = config.threads();
+
+#if (defined LITE_WITH_X86) && (defined PADDLE_WITH_MKLML) && \
+    !(defined LITE_ON_MODEL_OPTIMIZE_TOOL)
+  int num_threads = config.cpu_math_library_num_threads();
+  int real_num_threads = num_threads > 1 ? num_threads : 1;
+  paddle::lite::x86::MKL_Set_Num_Threads(real_num_threads);
+  omp_set_num_threads(real_num_threads);
+  VLOG(3) << "set_cpu_math_library_math_threads() is set successfully and the "
+             "number of threads is:"
+          << num_threads;
+#endif
 }
 
 std::unique_ptr<lite_api::Tensor> CxxPaddleApiImpl::GetInput(int i) {

lite/api/paddle_api.h

@@ -133,6 +133,7 @@ class LITE_API CxxConfig : public ConfigBase {
   std::string model_file_;
   std::string param_file_;
   bool model_from_memory_{false};
+  int cpu_math_library_math_threads_ = 1;
 
  public:
   void set_valid_places(const std::vector<Place>& x) { valid_places_ = x; }
@@ -151,6 +152,13 @@ class LITE_API CxxConfig : public ConfigBase {
   std::string model_file() const { return model_file_; }
   std::string param_file() const { return param_file_; }
   bool model_from_memory() const { return model_from_memory_; }
+
+  void set_cpu_math_library_math_threads(int threads) {
+    cpu_math_library_math_threads_ = threads;
+  }
+  int cpu_math_library_num_threads() const {
+    return cpu_math_library_math_threads_;
+  }
 };
 
 /// MobileConfig is the config for the light weight predictor, it will skip

lite/api/test_step_rnn_lite_x86.cc

@@ -30,6 +30,7 @@ TEST(Step_rnn, test_step_rnn_lite_x86) {
   std::string model_dir = FLAGS_model_dir;
   lite_api::CxxConfig config;
   config.set_model_dir(model_dir);
+  config.set_cpu_math_library_math_threads(10);
   config.set_valid_places({lite_api::Place{TARGET(kX86), PRECISION(kInt64)},
                            lite_api::Place{TARGET(kX86), PRECISION(kFloat)},
                            lite_api::Place{TARGET(kHost), PRECISION(kFloat)}});