Move transform_model_pre_registration in hf_checkpointer (#1664)

Co-authored-by: Daniel King <43149077+dakinggg@users.noreply.github.com>

llmfoundry/callbacks/hf_checkpointer.py

@@ -784,6 +784,10 @@ def tensor_hook(
 
         if dist.get_global_rank() == 0:
             if register_to_mlflow:
+                assert new_model_instance is not None
+                new_model_instance = self.transform_model_pre_registration(
+                    new_model_instance,
+                )
                 if self.using_peft:
 
                     # Save and register peft model to mlflow, this code path uses our older two step logic
@@ -798,10 +802,6 @@ def tensor_hook(
                         temp_save_dir,
                         'register_save',
                     )
-                    assert new_model_instance is not None
-                    new_model_instance = self.transform_model_pre_registration(
-                        new_model_instance,
-                    )
                     new_model_instance.save_pretrained(
                         register_save_dir,
                         max_shard_size='1GB',
@@ -860,9 +860,6 @@ def _save_and_register_peft_model(
         original_tokenizer: Optional[Any],
         save_dir: str,
     ):
-        new_model_instance = self.transform_model_pre_registration(
-            new_model_instance,
-        )
         components = {'model': new_model_instance}
         if original_tokenizer is not None:
             components['tokenizer'] = original_tokenizer

tests/a_scripts/inference/test_convert_composer_to_hf.py

@@ -624,7 +624,7 @@ def test_huggingface_conversion_callback_interval(
 def _get_model_and_tokenizer(
     model: str,
     max_seq_len: int,
-    tie_word_embeddings: bool,
+    tie_word_embeddings: Optional[bool],
     precision: str,
 ):
     if model == 'mpt':
@@ -1110,6 +1110,76 @@ def test_huggingface_conversion_callback(
     delete_transformers_cache()
 
 
+@patch('os.cpu_count', MagicMock(return_value=1))
+@patch(
+    'llmfoundry.callbacks.hf_checkpointer.SpawnProcess',
+    new=MockSpawnProcess,
+)
+def test_transform_model_pre_registration():
+    """Test `transform_model_pre_registration` method is called."""
+
+    class ExtendedHuggingFaceCheckpointer(HuggingFaceCheckpointer):
+        """Set PEFT to false before registering for testing."""
+
+        def transform_model_pre_registration(self, model: PreTrainedModel):
+            self.using_peft = False
+            return super().transform_model_pre_registration(model)
+
+    model_cfg, tokenizer_name = _get_model_and_tokenizer(
+        model='neo',
+        max_seq_len=10,
+        tie_word_embeddings=None,
+        precision='bfloat16',
+    )
+    model_cfg['peft_config'] = {
+        'peft_type': 'LORA',
+        'task_type': 'CAUSAL_LM',
+        'lora_alpha': 32,
+        'lora_dropout': 0.05,
+        'r': 16,
+        'target_modules': 'all-linear',
+    }
+    tokenizer = build_tokenizer(
+        tokenizer_name=tokenizer_name,
+        tokenizer_kwargs={},
+    )
+
+    original_model = build_composer_model(
+        model_cfg.pop('name'),
+        tokenizer=tokenizer,
+        cfg=model_cfg,
+    )
+
+    logger = MagicMock()
+    state = MagicMock()
+    state.timestamp.batch = 1
+    state.is_model_ddp = False
+    state.model = original_model
+    state.model.tokenizer = tokenizer
+
+    checkpointer = ExtendedHuggingFaceCheckpointer(
+        save_folder='test',
+        save_interval='1ba',
+    )
+    mlflow_logger_mock = _create_mlflow_logger_mock()
+    checkpointer.mlflow_loggers = [mlflow_logger_mock]  # type: ignore
+
+    assert model_cfg is not None
+    assert tokenizer_name is not None
+
+    checkpointer._save_and_register_peft_model = MagicMock()
+    checkpointer.using_peft = True
+    checkpointer._save_checkpoint(
+        state=state,
+        logger=logger,
+        upload_to_save_folder=True,
+        register_to_mlflow=True,
+    )
+
+    checkpointer._save_and_register_peft_model.assert_not_called()
+    assert mlflow_logger_mock.log_model.call_count == 1
+
+
 # TODO(GRT-2431): Refactor as enums
 @pytest.mark.parametrize(
     'model,tie_word_embeddings',