support mnist and resnet dygraph_to_static test (#25774)

* support mnist and resnet dygraph_to_static test

* make FLAGS_use_mkldnn a public flag

* fix test_get_set_flags

* Change name of a function

* Rerun CIs commit

* Fix oneDNN dygraph training
Co-authored-by: NAdam <38704900+grygielski@users.noreply.github.com>
Co-authored-by: Ngrygielski <adam.grygielski@gmail.com>

python/paddle/fluid/layer_helper.py

@@ -147,8 +147,10 @@ class LayerHelper(LayerHelperBase):
 
         if 'use_cudnn' in self.kwargs and self.kwargs.get('use_cudnn'):
             act['use_cudnn'] = self.kwargs.get('use_cudnn')
-        if 'use_mkldnn' in self.kwargs:
-            act['use_mkldnn'] = self.kwargs.get('use_mkldnn')
+        use_mkldnn = self.kwargs.get(
+            'use_mkldnn', core.globals().get("FLAGS_use_mkldnn", False))
+        if use_mkldnn:
+            act['use_mkldnn'] = use_mkldnn
         act_type = act.pop('type')
 
         tmp = self.create_variable_for_type_inference(dtype=input_var.dtype)

python/paddle/fluid/tests/unittests/dygraph_to_static/test_mnist.py

@@ -154,6 +154,18 @@ class TestMNISTWithToStatic(TestMNIST):
             msg='dygraph is {}\n static_res is \n{}'.format(dygraph_loss,
                                                             static_loss))
 
+    def test_mnist_declarative_cpu_vs_mkldnn(self):
+        dygraph_loss_cpu = self.train_dygraph()
+        fluid.set_flags({'FLAGS_use_mkldnn': True})
+        try:
+            dygraph_loss_mkldnn = self.train_dygraph()
+        finally:
+            fluid.set_flags({'FLAGS_use_mkldnn': False})
+        self.assertTrue(
+            np.allclose(dygraph_loss_cpu, dygraph_loss_mkldnn),
+            msg='cpu dygraph is {}\n mkldnn dygraph is \n{}'.format(
+                dygraph_loss_cpu, dygraph_loss_mkldnn))
+
     def train(self, to_static=False):
         prog_trans = ProgramTranslator()
         prog_trans.enable(to_static)

python/paddle/fluid/tests/unittests/dygraph_to_static/test_resnet.py

@@ -346,6 +346,13 @@ class TestResnet(unittest.TestCase):
                                                              dygraph_loss))
         self.verify_predict()
 
+    def test_in_static_mode_mkldnn(self):
+        fluid.set_flags({'FLAGS_use_mkldnn': True})
+        try:
+            train(to_static=True)
+        finally:
+            fluid.set_flags({'FLAGS_use_mkldnn': False})
+
 
 if __name__ == '__main__':
     unittest.main()