Allow user to specify huggingface link or local path to pretrained lo…

…ra weights (#3572)

ludwig/api.py

@@ -615,6 +615,14 @@ def on_epoch_end(self, trainer, progress_tracker, save_path):
                 # auto tune batch size
                 self._tune_batch_size(trainer, training_set, random_seed=random_seed)
 
+                if (
+                    self.config_obj.model_type == "LLM"
+                    and trainer.config.type == "none"
+                    and self.config_obj.adapter is not None
+                    and self.config_obj.adapter.pretrained_adapter_weights is not None
+                ):
+                    trainer.model.initialize_adapter()  # Load pre-trained adapter weights for inference only
+
                 # train model
                 if self.backend.is_coordinator():
                     print_boxed("TRAINING")

ludwig/config_validation/checks.py

@@ -494,6 +494,14 @@ def check_llm_finetuning_trainer_config(config: "ModelConfig"):  # noqa: F821
     if config.model_type != MODEL_LLM:
         return
 
+    if (
+        config.trainer.type == "none"
+        and config.adapter is not None
+        and config.adapter.pretrained_adapter_weights is not None
+    ):
+        # If performing zero-shot, we must specify pretrained adapter weights
+        return
+
     if config.adapter is not None and config.trainer.type != "finetune":
         raise ConfigValidationError("LLM finetuning requires trainer type to be finetune.")
 
@@ -509,7 +517,11 @@ def check_llm_finetuning_backend_config(config: "ModelConfig"):  # noqa: F821
         return
 
     # LLM finetuning is only supported by the finetune trainer type
-    if config.trainer.type != "finetune":
+    if (
+        config.trainer.type != "finetune"
+        and config.adapter is not None
+        and config.adapter.pretrained_adapter_weights is not None
+    ):
         return
 
     # Using local backend, so skip the checks below
@@ -529,9 +541,8 @@ def check_llm_finetuning_backend_config(config: "ModelConfig"):  # noqa: F821
 def check_llm_finetuning_adalora_config(config: "ModelConfig"):
     """Checks that the adalora adapter is configured correctly.
 
-    It requires a set of target_modules to be specified in the config for the model. If it isn't specified by the user,
-    we also check against PEFT's predefined target module list for ADALORA to see if this key is present there. If
-    neither is true, AdaloraModel will run into issues downstream.
+    We check against PEFT's predefined target module list for ADALORA to see if this target_modules is present there. If
+    not, AdaloraModel will run into issues downstream.
     """
     if config.model_type != MODEL_LLM:
         return
@@ -545,10 +556,7 @@ def check_llm_finetuning_adalora_config(config: "ModelConfig"):
     from peft.utils import TRANSFORMERS_MODELS_TO_ADALORA_TARGET_MODULES_MAPPING
 
     model_config = _get_llm_model_config(config.base_model)
-    if (
-        not config.adapter.target_modules
-        and model_config.model_type not in TRANSFORMERS_MODELS_TO_ADALORA_TARGET_MODULES_MAPPING
-    ):
+    if model_config.model_type not in TRANSFORMERS_MODELS_TO_ADALORA_TARGET_MODULES_MAPPING:
         raise ConfigValidationError(
             f"Adalora adapter is not supported for {model_config.model_type} model. "
             f"Supported model types are: {list(TRANSFORMERS_MODELS_TO_ADALORA_TARGET_MODULES_MAPPING.keys())}. "

ludwig/constants.py

@@ -282,6 +282,7 @@
 GENERATION = "generation"
 PROMPT = "prompt"
 ADAPTER = "adapter"
+PRETRAINED_ADAPTER_WEIGHTS = "pretrained_adapter_weights"
 
 # CrossEntropyLoss for LLMs
 IGNORE_INDEX_TOKEN_ID = -100

ludwig/models/llm.py

@@ -216,18 +216,51 @@ def output_feature_decoder(self) -> OutputFeature:
     def initialize_adapter(self):
         """If an adapter config is provided, we want to wrap the model with a PEFT model for fine-tuning."""
         if self.config_obj.adapter:
-            if self.config_obj.trainer.type != "finetune":
+            if self.config_obj.trainer.type != "finetune" and not self.config_obj.adapter.pretrained_adapter_weights:
                 raise ValueError(
                     "Adapter config was provided, but trainer type is not set to `finetune`. Either set the trainer to "
                     "`finetune` or remove the adapter config."
                 )
 
-            from peft import get_peft_model, TaskType
+            from peft import get_peft_model
+
+            if self.config_obj.adapter.pretrained_adapter_weights:
+                logger.info(f"Using pretrained adapter weights: {self.config_obj.adapter.pretrained_adapter_weights}")
+                # If pretrained adapter weights are provided, we want to load them into the model
+                from peft import MODEL_TYPE_TO_PEFT_MODEL_MAPPING, PeftConfig
+
+                peft_config = PeftConfig.from_pretrained(self.config_obj.adapter.pretrained_adapter_weights)
+                peft_dict = peft_config.to_dict()
+
+                # Need to update the peft config with some of the values from config_obj because not all of them are set
+                for param_name, param_value in self.config_obj.adapter.to_config().to_dict().items():
+                    # Not all parameters are supported by all models, so we only add the parameter to the load kwargs
+                    # if it is supported by the model.
+                    if param_value is None:
+                        # param_name and param_value come from the config object and contain default
+                        # values for the adapter. Examples of parameters with missing values might be:
+                        # 'auto_mapping', 'base_model_name_or_path', and 'task_type'.
+                        # Note that some of these values might already be set in peft_config, which comes from HF
+                        # directly (specifically, adapter_config.json in the model repo), and we don't want to override
+                        # those values with None.
+                        continue
+                    if param_name not in peft_dict:
+                        # If any parameters are not set in adapter_config.json in HF, we want to populate them with the
+                        # appropriate default values.
+                        setattr(peft_config, param_name, param_value)
+
+                self.model = MODEL_TYPE_TO_PEFT_MODEL_MAPPING[peft_config.task_type].from_pretrained(
+                    self.model, self.config_obj.adapter.pretrained_adapter_weights
+                )
+            else:
+                # If no pretrained adapter is provided, we want to load untrained weights into the model
+                from peft import TaskType
 
-            peft_config = self.config_obj.adapter.to_config(
-                task_type=TaskType.CAUSAL_LM, tokenizer_name_or_path=self.model_name
-            )
-            self.model = get_peft_model(self.model, peft_config)
+                peft_config = self.config_obj.adapter.to_config(
+                    task_type=TaskType.CAUSAL_LM, tokenizer_name_or_path=self.model_name
+                )
+
+                self.model = get_peft_model(self.model, peft_config)
 
             logger.info("==================================================")
             logger.info("Trainable Parameter Summary For Fine-Tuning")

ludwig/schema/llms/peft.py

@@ -30,6 +30,10 @@ def wrap(config: BaseAdapterConfig):
 class BaseAdapterConfig(schema_utils.BaseMarshmallowConfig, ABC):
     type: str
 
+    pretrained_adapter_weights: Optional[str] = schema_utils.String(
+        default=None, description="Path to pretrained weights.", allow_none=True
+    )
+
     @abstractmethod
     def to_config(self, **kwargs) -> "PeftConfig":
         pass
@@ -359,7 +363,7 @@ def description(cls) -> str:
 @register_adapter("adaption_prompt")
 @ludwig_dataclass
 class AdaptionPromptConfig(BaseAdapterConfig):
-    """Adapted from https://github.com/huggingface/peft/blob/main/src/peft/tuners/adaption_prompt.py."""
+    """Adapted from https://github.com/huggingface/peft/blob/main/src/peft/tuners/adaption_prompt/config.py."""
 
     def __post_init__(self):
         if not self.adapter_len:

tests/integration_tests/test_llm.py

@@ -18,6 +18,7 @@
     MODEL_TYPE,
     OUTPUT_FEATURES,
     PREPROCESSING,
+    PRETRAINED_ADAPTER_WEIGHTS,
     PROMPT,
     TRAINER,
     TYPE,
@@ -492,12 +493,61 @@ def test_default_max_sequence_length():
             BATCH_SIZE: 8,
             EPOCHS: 2,
         },
+        ADAPTER: {TYPE: "lora", PRETRAINED_ADAPTER_WEIGHTS: "Infernaught/test_adapter_weights"},
+        BACKEND: {TYPE: "local"},
     }
     config_obj = ModelConfig.from_dict(config)
     assert config_obj.input_features[0].preprocessing.max_sequence_length is None
     assert config_obj.output_features[0].preprocessing.max_sequence_length is None
 
 
+@pytest.mark.parametrize("adapter", ["lora", "adalora", "adaption_prompt"])
+def test_load_pretrained_adapter_weights(adapter):
+    from peft import PeftModel
+    from transformers import PreTrainedModel
+
+    weights = ""
+    model = ""
+    if adapter == "lora":
+        weights = "Infernaught/test_adapter_weights"
+        base_model = TEST_MODEL_NAME
+    elif adapter == "adalora":
+        weights = "Infernaught/test_adalora_weights"
+        base_model = "HuggingFaceH4/tiny-random-LlamaForCausalLM"
+    elif adapter == "adaption_prompt":
+        weights = "Infernaught/test_ap_weights"
+        base_model = "HuggingFaceH4/tiny-random-LlamaForCausalLM"
+    else:
+        raise ()
+
+    config = {
+        MODEL_TYPE: MODEL_LLM,
+        BASE_MODEL: base_model,
+        INPUT_FEATURES: [text_feature(name="input", encoder={"type": "passthrough"})],
+        OUTPUT_FEATURES: [text_feature(name="output")],
+        TRAINER: {
+            TYPE: "none",
+            BATCH_SIZE: 8,
+            EPOCHS: 2,
+        },
+        ADAPTER: {TYPE: adapter, PRETRAINED_ADAPTER_WEIGHTS: weights},
+        BACKEND: {TYPE: "local"},
+    }
+    config_obj = ModelConfig.from_dict(config)
+    model = LLM(config_obj)
+
+    assert model.config_obj.adapter.pretrained_adapter_weights
+    assert model.config_obj.adapter.pretrained_adapter_weights == weights
+
+    model.prepare_for_training()
+    assert not isinstance(model.model, PreTrainedModel)
+    assert isinstance(model.model, PeftModel)
+
+    config_obj = ModelConfig.from_dict(config)
+    assert config_obj.input_features[0].preprocessing.max_sequence_length is None
+    assert config_obj.output_features[0].preprocessing.max_sequence_length is None
+
+
 def _compare_models(model_1: torch.nn.Module, model_2: torch.nn.Module) -> bool:
     # Source: https://discuss.pytorch.org/t/check-if-models-have-same-weights/4351/6
     for key_item_1, key_item_2 in zip(model_1.state_dict().items(), model_2.state_dict().items()):