[timm_wrapper] add support for gradient checkpointing (#39287)

* feat: add support for gradient checkpointing in TimmWrapperModel and TimmWrapperForImageClassification

* ruff fix

* refactor + add test for not supported model

* ruff

* Update src/transformers/models/timm_wrapper/modeling_timm_wrapper.py

Co-authored-by: Pavel Iakubovskii <qubvel@gmail.com>

* Update src/transformers/models/timm_wrapper/modeling_timm_wrapper.py

Co-authored-by: Pavel Iakubovskii <qubvel@gmail.com>

* Update src/transformers/models/timm_wrapper/modeling_timm_wrapper.py

Co-authored-by: Pavel Iakubovskii <qubvel@gmail.com>

* Update src/transformers/models/timm_wrapper/modeling_timm_wrapper.py

Co-authored-by: Pavel Iakubovskii <qubvel@gmail.com>

---------

Co-authored-by: Pavel Iakubovskii <qubvel@gmail.com>

src/transformers/models/timm_wrapper/modeling_timm_wrapper.py

@@ -70,6 +70,10 @@ class TimmWrapperPreTrainedModel(PreTrainedModel):
         requires_backends(self, ["vision", "timm"])
         super().__init__(*args, **kwargs)
 
+    def post_init(self):
+        self.supports_gradient_checkpointing = self._timm_model_supports_gradient_checkpointing()
+        super().post_init()
+
     @staticmethod
     def _fix_state_dict_key_on_load(key) -> tuple[str, bool]:
         """
@@ -107,6 +111,24 @@ class TimmWrapperPreTrainedModel(PreTrainedModel):
             if module.bias is not None:
                 module.bias.data.zero_()
 
+    def _timm_model_supports_gradient_checkpointing(self):
+        """
+        Check if the timm model supports gradient checkpointing by checking if the `set_grad_checkpointing` method is available.
+        Some timm models will have the method but will raise an AssertionError when called so in this case we return False.
+        """
+        if not hasattr(self.timm_model, "set_grad_checkpointing"):
+            return False
+
+        try:
+            self.timm_model.set_grad_checkpointing(enable=True)
+            self.timm_model.set_grad_checkpointing(enable=False)
+            return True
+        except Exception:
+            return False
+
+    def _set_gradient_checkpointing(self, enable: bool = True, *args, **kwargs):
+        self.timm_model.set_grad_checkpointing(enable)
+
 
 class TimmWrapperModel(TimmWrapperPreTrainedModel):
     """

tests/models/timm_wrapper/test_modeling_timm_wrapper.py

@@ -170,6 +170,16 @@ class TimmWrapperModelTest(ModelTesterMixin, PipelineTesterMixin, unittest.TestC
     def test_model_is_small(self):
         pass
 
+    def test_gradient_checkpointing(self):
+        config, _ = self.model_tester.prepare_config_and_inputs_for_common()
+        model = TimmWrapperModel._from_config(config)
+        self.assertTrue(model.supports_gradient_checkpointing)
+
+    def test_gradient_checkpointing_on_non_supported_model(self):
+        config = TimmWrapperConfig.from_pretrained("timm/hrnet_w18.ms_aug_in1k")
+        model = TimmWrapperModel._from_config(config)
+        self.assertFalse(model.supports_gradient_checkpointing)
+
     def test_forward_signature(self):
         config, _ = self.model_tester.prepare_config_and_inputs_for_common()