!605 fix default parameter set in model

Merge pull request !605 from liubuyu/master

mindspore/train/model.py

@@ -99,12 +99,8 @@ class Model:
         self._loss_scale_manager_set = False
         self._keep_bn_fp32 = True
         self._check_kwargs(kwargs)
-        if 'keep_batchnorm_fp32' in kwargs:
-            self._keep_bn_fp32 = kwargs['keep_batchnorm_fp32']
-        if 'loss_scale_manager' in kwargs:
-            self._loss_scale_manager = kwargs['loss_scale_manager']
-            self._loss_scale_manager_set = True
         self._amp_level = amp_level
+        self._process_amp_args(kwargs)
         self._parallel_mode = _get_parallel_mode()
         self._device_number = _get_device_num()
         self._global_rank = _get_global_rank()
@@ -114,6 +110,15 @@ class Model:
         self._build_eval_network(metrics, eval_network, eval_indexes)
         self._build_predict_network()
 
+    def _process_amp_args(self, kwargs):
+        if self._amp_level == "O0":
+            self._keep_bn_fp32 = False
+        if 'keep_batchnorm_fp32' in kwargs:
+            self._keep_bn_fp32 = kwargs['keep_batchnorm_fp32']
+        if 'loss_scale_manager' in kwargs:
+            self._loss_scale_manager = kwargs['loss_scale_manager']
+            self._loss_scale_manager_set = True
+
     def _check_kwargs(self, kwargs):
         for arg in kwargs:
             if arg not in ['loss_scale_manager', 'keep_batchnorm_fp32']: