ImageConductor / peft /peft_model.py
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# Copyright 2023-present the HuggingFace Inc. team.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import annotations
import collections
import inspect
import os
import warnings
from contextlib import contextmanager
from copy import deepcopy
from dataclasses import dataclass
from typing import Any, Literal, Optional, Union
import packaging.version
import torch
import transformers
from accelerate import dispatch_model, infer_auto_device_map
from accelerate.hooks import AlignDevicesHook, add_hook_to_module, remove_hook_from_submodules
from accelerate.utils import get_balanced_memory, named_module_tensors
from huggingface_hub import ModelCard, ModelCardData, hf_hub_download
from safetensors import safe_open
from safetensors.torch import save_file as safe_save_file
from torch.nn import BCEWithLogitsLoss, CrossEntropyLoss, MSELoss
from transformers import PreTrainedModel
from transformers.modeling_outputs import QuestionAnsweringModelOutput, SequenceClassifierOutput, TokenClassifierOutput
from transformers.utils import PushToHubMixin
from . import __version__
from .config import PeftConfig
from .tuners import (
AdaLoraModel,
AdaptionPromptModel,
BOFTModel,
IA3Model,
LNTuningModel,
LoHaModel,
LoKrModel,
LoraModel,
MultitaskPromptEmbedding,
OFTModel,
PolyModel,
PrefixEncoder,
PromptEmbedding,
PromptEncoder,
VeraModel,
)
from .tuners.tuners_utils import BaseTuner, BaseTunerLayer
from .utils import (
SAFETENSORS_WEIGHTS_NAME,
TRANSFORMERS_MODELS_TO_PREFIX_TUNING_POSTPROCESS_MAPPING,
WEIGHTS_NAME,
PeftType,
TaskType,
_get_batch_size,
_prepare_prompt_learning_config,
_set_adapter,
_set_trainable,
get_peft_model_state_dict,
id_tensor_storage,
infer_device,
load_peft_weights,
set_peft_model_state_dict,
shift_tokens_right,
)
PEFT_TYPE_TO_MODEL_MAPPING = {
PeftType.LORA: LoraModel,
PeftType.LOHA: LoHaModel,
PeftType.LOKR: LoKrModel,
PeftType.PROMPT_TUNING: PromptEmbedding,
PeftType.P_TUNING: PromptEncoder,
PeftType.PREFIX_TUNING: PrefixEncoder,
PeftType.ADALORA: AdaLoraModel,
PeftType.BOFT: BOFTModel,
PeftType.ADAPTION_PROMPT: AdaptionPromptModel,
PeftType.IA3: IA3Model,
PeftType.OFT: OFTModel,
PeftType.POLY: PolyModel,
PeftType.LN_TUNING: LNTuningModel,
PeftType.VERA: VeraModel,
}
class PeftModel(PushToHubMixin, torch.nn.Module):
"""
Base model encompassing various Peft methods.
Args:
model ([`~transformers.PreTrainedModel`]): The base transformer model used for Peft.
peft_config ([`PeftConfig`]): The configuration of the Peft model.
adapter_name (`str`, *optional*): The name of the adapter, defaults to `"default"`.
**Attributes**:
- **base_model** ([`torch.nn.Module`]) -- The base transformer model used for Peft.
- **peft_config** ([`PeftConfig`]) -- The configuration of the Peft model.
- **modules_to_save** (`list` of `str`) -- The list of sub-module names to save when
saving the model.
- **prompt_encoder** ([`PromptEncoder`]) -- The prompt encoder used for Peft if
using [`PromptLearningConfig`].
- **prompt_tokens** (`torch.Tensor`) -- The virtual prompt tokens used for Peft if
using [`PromptLearningConfig`].
- **transformer_backbone_name** (`str`) -- The name of the transformer
backbone in the base model if using [`PromptLearningConfig`].
- **word_embeddings** (`torch.nn.Embedding`) -- The word embeddings of the transformer backbone
in the base model if using [`PromptLearningConfig`].
"""
def __init__(self, model: PreTrainedModel, peft_config: PeftConfig, adapter_name: str = "default") -> None:
super().__init__()
self.modules_to_save = None
self.active_adapter = adapter_name
self.peft_type = peft_config.peft_type
# These args are special PEFT arguments that users can pass. They need to be removed before passing them to
# forward.
self.special_peft_forward_args = {"adapter_names"}
self._is_prompt_learning = peft_config.is_prompt_learning
if self._is_prompt_learning:
self._peft_config = {adapter_name: peft_config}
self.base_model = model
self.add_adapter(adapter_name, peft_config)
else:
self._peft_config = None
cls = PEFT_TYPE_TO_MODEL_MAPPING[peft_config.peft_type]
self.base_model = cls(model, {adapter_name: peft_config}, adapter_name)
self.set_additional_trainable_modules(peft_config, adapter_name)
if getattr(model, "is_gradient_checkpointing", True):
model = self._prepare_model_for_gradient_checkpointing(model)
# the `pretraining_tp` is set for some models to simulate Tensor Parallelism during inference to avoid
# numerical differences, https://github.com/pytorch/pytorch/issues/76232 - to avoid any unexpected
# behavior we disable that in this line.
if hasattr(self.base_model, "config") and hasattr(self.base_model.config, "pretraining_tp"):
self.base_model.config.pretraining_tp = 1
@property
def peft_config(self) -> dict[str, PeftConfig]:
if self._is_prompt_learning:
return self._peft_config
return self.base_model.peft_config
@property
def active_adapters(self) -> list[str]:
try:
adapters = self.base_model.active_adapters
except AttributeError:
adapters = self.active_adapter
if isinstance(adapters, str):
adapters = [adapters]
return adapters
@peft_config.setter
def peft_config(self, value: dict[str, PeftConfig]):
if self._is_prompt_learning:
self._peft_config = value
else:
self.base_model.peft_config = value
def save_pretrained(
self,
save_directory: str,
safe_serialization: bool = True,
selected_adapters: Optional[list[str]] = None,
save_embedding_layers: Union[str, bool] = "auto",
is_main_process: bool = True,
convert_pissa_to_lora: Optional[str] = None,
**kwargs: Any,
) -> None:
r"""
This function saves the adapter model and the adapter configuration files to a directory, so that it can be
reloaded using the [`PeftModel.from_pretrained`] class method, and also used by the [`PeftModel.push_to_hub`]
method.
Args:
save_directory (`str`):
Directory where the adapter model and configuration files will be saved (will be created if it does not
exist).
safe_serialization (`bool`, *optional*):
Whether to save the adapter files in safetensors format, defaults to `True`.
selected_adapters (`List[str]`, *optional*):
A list of adapters to be saved. If `None`, will default to all adapters.
save_embedding_layers (`Union[bool, str]`, *optional*, defaults to `"auto"`):
If `True`, save the embedding layers in addition to adapter weights. If `auto`, checks the common
embedding layers `peft.utils.other.EMBEDDING_LAYER_NAMES` in config's `target_modules` when available.
and automatically sets the boolean flag. This only works for 🤗 transformers models.
is_main_process (`bool`, *optional*):
Whether the process calling this is the main process or not. Will default to `True`. Will not save the
checkpoint if not on the main process, which is important for multi device setups (e.g. DDP).
convert_pissa_to_lora (`str`):
The path to the initialized PiSSA adapter, which is obtained after initializing the model with PiSSA
and before performing any training. When `convert_pissa_to_lora` is not None, the difference in PISSA
before and after fine-tuning is calculated. This difference can be represented as the parameters of a
of a standard LoRA adapter. Using this converted adapter does not require changes to the base model,
thus conveniently allowing the use of multiple PISSA and LoRA adapters, and the activation or
deactivation of any adapters.
kwargs (additional keyword arguments, *optional*):
Additional keyword arguments passed along to the `push_to_hub` method.
"""
if os.path.isfile(save_directory):
raise ValueError(f"Provided path ({save_directory}) should be a directory, not a file")
if selected_adapters is None:
selected_adapters = list(self.peft_config.keys())
else:
if any(
selected_adapter_name not in list(self.peft_config.keys())
for selected_adapter_name in selected_adapters
):
raise ValueError(
f"You passed an invalid `selected_adapters` arguments, current supported adapter names are"
f" {list(self.peft_config.keys())} - got {selected_adapters}."
)
def save_pissa_as_lora(peft_config, convert_pissa_to_lora, output_state_dict, kwargs):
if not str(peft_config.init_lora_weights).startswith("pissa"):
warnings.warn("`convert_pissa_to_lora` only works for converting a PiSSA adapter to a LoRA adapter")
initial_adapter = os.path.basename(convert_pissa_to_lora)
self.load_adapter(
os.path.dirname(convert_pissa_to_lora), subfolder=initial_adapter, adapter_name=initial_adapter
)
if str(self.peft_config[initial_adapter].init_lora_weights).startswith("pissa"):
raise ValueError(
"The `init_lora_weights` parameter of the initial PiSSA adapter should be set to `True`. "
"Otherwise, `self.load_adapter` will subtract the principal singular value and vector again based on the residual model."
)
output_state_dict = self.base_model.subtract_pissa_init(output_state_dict, initial_adapter, kwargs)
self.delete_adapter(adapter_name)
return output_state_dict
if is_main_process:
os.makedirs(save_directory, exist_ok=True)
self.create_or_update_model_card(save_directory)
for adapter_name in selected_adapters:
peft_config = self.peft_config[adapter_name]
# save only the trainable weights
output_state_dict = get_peft_model_state_dict(
self,
state_dict=kwargs.get("state_dict", None),
adapter_name=adapter_name,
save_embedding_layers=save_embedding_layers,
)
output_dir = os.path.join(save_directory, adapter_name) if adapter_name != "default" else save_directory
os.makedirs(output_dir, exist_ok=True)
if is_main_process and safe_serialization:
# Section copied from: https://github.com/huggingface/transformers/blob/main/src/transformers/modeling_utils.py#L2111-L2134
# Safetensors does not allow tensor aliasing.
# We're going to remove aliases before saving
ptrs = collections.defaultdict(list)
for name, tensor in output_state_dict.items():
# Sometimes in the state_dict we have non-tensor objects.
# e.g. in bitsandbytes we have some `str` objects in the state_dict
if isinstance(tensor, torch.Tensor):
ptrs[id_tensor_storage(tensor)].append(name)
else:
# In the non-tensor case, fall back to the pointer of the object itself
ptrs[id(tensor)].append(name)
# These are all the pointers of shared tensors.
shared_ptrs = {ptr: names for ptr, names in ptrs.items() if len(names) > 1}
for _, names in shared_ptrs.items():
# Here we just clone the shared tensors to avoid tensor aliasing which is
# not supported in safetensors.
for shared_tensor_name in names[1:]:
output_state_dict[shared_tensor_name] = output_state_dict[shared_tensor_name].clone()
if convert_pissa_to_lora is not None:
output_state_dict = save_pissa_as_lora(
peft_config, convert_pissa_to_lora, output_state_dict, kwargs
)
safe_save_file(
output_state_dict,
os.path.join(output_dir, SAFETENSORS_WEIGHTS_NAME),
metadata={"format": "pt"},
)
elif is_main_process:
if convert_pissa_to_lora is not None:
output_state_dict = save_pissa_as_lora(
peft_config, convert_pissa_to_lora, output_state_dict, kwargs
)
torch.save(output_state_dict, os.path.join(output_dir, WEIGHTS_NAME))
# save the config and change the inference mode to `True`
if peft_config.base_model_name_or_path is None:
peft_config.base_model_name_or_path = (
self.base_model.__dict__.get("name_or_path", None)
if peft_config.is_prompt_learning
else self.base_model.model.__dict__.get("name_or_path", None)
)
inference_mode = peft_config.inference_mode
peft_config.inference_mode = True
if peft_config.task_type is None:
# deal with auto mapping
base_model_class = self._get_base_model_class(
is_prompt_tuning=peft_config.is_prompt_learning,
)
parent_library = base_model_class.__module__
auto_mapping_dict = {
"base_model_class": base_model_class.__name__,
"parent_library": parent_library,
}
else:
auto_mapping_dict = None
if is_main_process:
if convert_pissa_to_lora is not None:
peft_config.init_lora_weights = True
peft_config.r *= 2
peft_config.lora_alpha *= 2
peft_config.save_pretrained(output_dir, auto_mapping_dict=auto_mapping_dict)
peft_config.inference_mode = inference_mode
@classmethod
def from_pretrained(
cls,
model: torch.nn.Module,
model_id: Union[str, os.PathLike],
adapter_name: str = "default",
is_trainable: bool = False,
config: Optional[PeftConfig] = None,
**kwargs: Any,
) -> PeftModel:
r"""
Instantiate a PEFT model from a pretrained model and loaded PEFT weights.
Note that the passed `model` may be modified inplace.
Args:
model ([`torch.nn.Module`]):
The model to be adapted. For 🤗 Transformers models, the model should be initialized with the
[`~transformers.PreTrainedModel.from_pretrained`].
model_id (`str` or `os.PathLike`):
The name of the PEFT configuration to use. Can be either:
- A string, the `model id` of a PEFT configuration hosted inside a model repo on the Hugging Face
Hub.
- A path to a directory containing a PEFT configuration file saved using the `save_pretrained`
method (`./my_peft_config_directory/`).
adapter_name (`str`, *optional*, defaults to `"default"`):
The name of the adapter to be loaded. This is useful for loading multiple adapters.
is_trainable (`bool`, *optional*, defaults to `False`):
Whether the adapter should be trainable or not. If `False`, the adapter will be frozen and can only be
used for inference.
config ([`~peft.PeftConfig`], *optional*):
The configuration object to use instead of an automatically loaded configuration. This configuration
object is mutually exclusive with `model_id` and `kwargs`. This is useful when configuration is already
loaded before calling `from_pretrained`.
kwargs: (`optional`):
Additional keyword arguments passed along to the specific PEFT configuration class.
"""
from .mapping import MODEL_TYPE_TO_PEFT_MODEL_MAPPING, PEFT_TYPE_TO_CONFIG_MAPPING
# load the config
if config is None:
config = PEFT_TYPE_TO_CONFIG_MAPPING[
PeftConfig._get_peft_type(
model_id,
subfolder=kwargs.get("subfolder", None),
revision=kwargs.get("revision", None),
cache_dir=kwargs.get("cache_dir", None),
use_auth_token=kwargs.get("use_auth_token", None),
token=kwargs.get("token", None),
)
].from_pretrained(model_id, **kwargs)
elif isinstance(config, PeftConfig):
config.inference_mode = not is_trainable
else:
raise ValueError(f"The input config must be a PeftConfig, got {config.__class__}")
if hasattr(model, "hf_device_map"):
weight_map = dict(named_module_tensors(model, recurse=True))
# recreate the offload_index for disk-offloaded modules: we need to know the location in storage of each weight
# before the offload hook is removed from the model
disk_modules = set()
index = None
for name, module in model.named_modules():
if hasattr(module, "_hf_hook") and hasattr(module._hf_hook, "original_devices"):
if hasattr(module._hf_hook.weights_map, "dataset"):
index = module._hf_hook.weights_map.dataset.index
for key in module._hf_hook.original_devices.keys():
if module._hf_hook.original_devices[key] == torch.device("meta"):
disk_modules.add(str(name) + "." + str(key))
if disk_modules and not kwargs.get("use_safetensors", True):
raise ValueError("Disk offloading currently only supported for safetensors")
if index:
offload_index = {
p: {
"safetensors_file": index[p]["safetensors_file"],
"weight_name": p,
"dtype": str(weight_map[p].dtype).replace("torch.", ""),
}
for p in weight_map.keys()
if p in disk_modules
}
kwargs["offload_index"] = offload_index
if (getattr(model, "hf_device_map", None) is not None) and len(
set(model.hf_device_map.values()).intersection({"cpu", "disk"})
) > 0:
remove_hook_from_submodules(model)
if config.is_prompt_learning and is_trainable:
raise ValueError("Cannot set a prompt learning adapter to trainable when loading pretrained adapter.")
else:
config.inference_mode = not is_trainable
if config.task_type not in MODEL_TYPE_TO_PEFT_MODEL_MAPPING.keys():
model = cls(model, config, adapter_name)
else:
model = MODEL_TYPE_TO_PEFT_MODEL_MAPPING[config.task_type](model, config, adapter_name)
model.load_adapter(model_id, adapter_name, is_trainable=is_trainable, **kwargs)
return model
def _setup_prompt_encoder(self, adapter_name: str):
config = self.peft_config[adapter_name]
if not hasattr(self, "prompt_encoder"):
self.prompt_encoder = torch.nn.ModuleDict({})
self.prompt_tokens = {}
transformer_backbone = None
for name, module in self.base_model.named_children():
for param in module.parameters():
param.requires_grad = False
if isinstance(module, PreTrainedModel):
# Make sure to freeze Tranformers model
if transformer_backbone is None:
transformer_backbone = module
self.transformer_backbone_name = name
if transformer_backbone is None:
transformer_backbone = self.base_model
if config.num_transformer_submodules is None:
config.num_transformer_submodules = 2 if config.task_type == TaskType.SEQ_2_SEQ_LM else 1
for named_param, value in list(transformer_backbone.named_parameters()):
# for ZeRO-3, the tensor is sharded across accelerators and deepspeed modifies it to a tensor with shape [0]
# the actual unsharded shape is stored in "ds_shape" attribute
# special handling is needed in case the model is initialized in deepspeed.zero.Init() context or HfDeepSpeedConfig
# has been called before
# For reference refer to issue: https://github.com/huggingface/peft/issues/996
deepspeed_distributed_tensor_shape = getattr(value, "ds_shape", None)
if value.shape[0] == self.base_model.config.vocab_size or (
deepspeed_distributed_tensor_shape is not None
and deepspeed_distributed_tensor_shape[0] == self.base_model.config.vocab_size
):
self.word_embeddings = transformer_backbone.get_submodule(named_param.replace(".weight", ""))
break
if config.peft_type == PeftType.PROMPT_TUNING:
prompt_encoder = PromptEmbedding(config, self.word_embeddings)
elif config.peft_type == PeftType.MULTITASK_PROMPT_TUNING:
prompt_encoder = MultitaskPromptEmbedding(config, self.word_embeddings)
elif config.peft_type == PeftType.P_TUNING:
prompt_encoder = PromptEncoder(config)
elif config.peft_type == PeftType.PREFIX_TUNING:
prompt_encoder = PrefixEncoder(config)
else:
raise ValueError("Not supported")
prompt_encoder = prompt_encoder.to(self.device)
self.prompt_encoder.update(torch.nn.ModuleDict({adapter_name: prompt_encoder}))
self.prompt_tokens[adapter_name] = torch.arange(
config.num_virtual_tokens * config.num_transformer_submodules
).long()
def _prepare_model_for_gradient_checkpointing(self, model: PreTrainedModel):
r"""
Prepares the model for gradient checkpointing if necessary
"""
if not (
getattr(model, "is_loaded_in_8bit", False)
or getattr(model, "is_loaded_in_4bit", False)
or getattr(model, "is_quantized", False)
):
if hasattr(model, "enable_input_require_grads"):
model.enable_input_require_grads()
elif hasattr(model, "get_input_embeddings"):
def make_inputs_require_grad(module, input, output):
output.requires_grad_(True)
model.get_input_embeddings().register_forward_hook(make_inputs_require_grad)
return model
def get_prompt_embedding_to_save(self, adapter_name: str) -> torch.Tensor:
"""
Returns the prompt embedding to save when saving the model. Only applicable when using a prompt learning
method.
"""
prompt_encoder = self.prompt_encoder[adapter_name]
prompt_tokens = (
self.prompt_tokens[adapter_name].unsqueeze(0).expand(1, -1).to(prompt_encoder.embedding.weight.device)
)
if self.peft_config[adapter_name].peft_type == PeftType.PREFIX_TUNING:
prompt_tokens = prompt_tokens[:, : self.peft_config[adapter_name].num_virtual_tokens]
if self.peft_config[adapter_name].peft_type == PeftType.MULTITASK_PROMPT_TUNING:
prompt_embeddings = super(MultitaskPromptEmbedding, prompt_encoder).forward(prompt_tokens)
else:
prompt_embeddings = prompt_encoder(prompt_tokens)
return prompt_embeddings[0].detach().cpu()
def get_prompt(self, batch_size: int, task_ids: Optional[torch.Tensor] = None) -> torch.Tensor:
"""
Returns the virtual prompts to use for Peft. Only applicable when using a prompt learning method.
"""
peft_config = self.active_peft_config
prompt_encoder = self.prompt_encoder[self.active_adapter]
prompt_tokens = (
self.prompt_tokens[self.active_adapter]
.unsqueeze(0)
.expand(batch_size, -1)
.to(prompt_encoder.embedding.weight.device)
)
if peft_config.peft_type == PeftType.PREFIX_TUNING:
prompt_tokens = prompt_tokens[:, : peft_config.num_virtual_tokens]
if peft_config.inference_mode:
past_key_values = prompt_encoder.embedding.weight.repeat(batch_size, 1, 1)
else:
past_key_values = prompt_encoder(prompt_tokens)
if self.base_model_torch_dtype is not None:
past_key_values = past_key_values.to(self.base_model_torch_dtype)
past_key_values = past_key_values.view(
batch_size,
peft_config.num_virtual_tokens,
peft_config.num_layers * 2,
peft_config.num_attention_heads,
peft_config.token_dim // peft_config.num_attention_heads,
)
if peft_config.num_transformer_submodules == 2:
past_key_values = torch.cat([past_key_values, past_key_values], dim=2)
past_key_values = past_key_values.permute([2, 0, 3, 1, 4]).split(
peft_config.num_transformer_submodules * 2
)
if TRANSFORMERS_MODELS_TO_PREFIX_TUNING_POSTPROCESS_MAPPING.get(self.config.model_type, None) is not None:
post_process_fn = TRANSFORMERS_MODELS_TO_PREFIX_TUNING_POSTPROCESS_MAPPING[self.config.model_type]
past_key_values = post_process_fn(past_key_values)
return past_key_values
else:
if peft_config.peft_type == PeftType.MULTITASK_PROMPT_TUNING:
prompts = prompt_encoder(prompt_tokens, task_ids)
else:
if peft_config.inference_mode:
prompts = prompt_encoder.embedding.weight.repeat(batch_size, 1, 1)
else:
prompts = prompt_encoder(prompt_tokens)
return prompts
def get_nb_trainable_parameters(self) -> tuple[int, int]:
r"""
Returns the number of trainable parameters and the number of all parameters in the model.
"""
trainable_params = 0
all_param = 0
for _, param in self.named_parameters():
num_params = param.numel()
# if using DS Zero 3 and the weights are initialized empty
if num_params == 0 and hasattr(param, "ds_numel"):
num_params = param.ds_numel
# Due to the design of 4bit linear layers from bitsandbytes
# one needs to multiply the number of parameters by 2 to get
# the correct number of parameters
if param.__class__.__name__ == "Params4bit":
if hasattr(param, "element_size"):
num_bytes = param.element_size()
elif not hasattr(param, "quant_storage"):
num_bytes = 1
else:
num_bytes = param.quant_storage.itemsize
num_params = num_params * 2 * num_bytes
all_param += num_params
if param.requires_grad:
trainable_params += num_params
return trainable_params, all_param
def print_trainable_parameters(self) -> None:
"""
Prints the number of trainable parameters in the model.
Note: print_trainable_parameters() uses get_nb_trainable_parameters() which is different from
num_parameters(only_trainable=True) from huggingface/transformers. get_nb_trainable_parameters() returns
(trainable parameters, all parameters) of the Peft Model which includes modified backbone transformer model.
For techniques like LoRA, the backbone transformer model is modified in place with LoRA modules. However, for
prompt tuning, the backbone transformer model is unmodified. num_parameters(only_trainable=True) returns number
of trainable parameters of the backbone transformer model which can be different.
"""
trainable_params, all_param = self.get_nb_trainable_parameters()
print(
f"trainable params: {trainable_params:,d} || all params: {all_param:,d} || trainable%: {100 * trainable_params / all_param:.4f}"
)
def __getattr__(self, name: str):
"""Forward missing attributes to the wrapped module."""
try:
return super().__getattr__(name) # defer to nn.Module's logic
except AttributeError:
return getattr(self.base_model, name)
@contextmanager
def _enable_peft_forward_hooks(self, *args, **kwargs):
# If the base model has a method called _enable_peft_forward_hooks, it is invoked as a context. Otherwise, this
# runs without any changes
if hasattr(self.base_model, "_enable_peft_forward_hooks"):
with self.base_model._enable_peft_forward_hooks(*args, **kwargs):
yield
return
else:
# nothing to enable
yield
return
def forward(self, *args: Any, **kwargs: Any):
"""
Forward pass of the model.
"""
with self._enable_peft_forward_hooks(*args, **kwargs):
kwargs = {k: v for k, v in kwargs.items() if k not in self.special_peft_forward_args}
return self.get_base_model()(*args, **kwargs)
def generate(self, *args, **kwargs):
with self._enable_peft_forward_hooks(*args, **kwargs):
kwargs = {k: v for k, v in kwargs.items() if k not in self.special_peft_forward_args}
return self.get_base_model().generate(*args, **kwargs)
def _get_base_model_class(self, is_prompt_tuning=False):
"""
Returns the base model class.
"""
if not is_prompt_tuning:
return self.base_model.model.__class__
return self.base_model.__class__
@contextmanager
def disable_adapter(self):
"""
Context manager that disables the adapter module. Use this to run inference on the base model.
Example:
```py
>>> with model.disable_adapter():
... model(inputs)
```
"""
if self.peft_config[self.active_adapter].is_prompt_learning:
try:
# TODO: consider replacing this patching of methods with a more robust mechanism: setting a flag and
# letting the underlying methods deal with it, same as how LoRA does it.
old_forward = self.forward
self.forward = self.base_model.forward
old_prepare_inputs_for_generation = self.prepare_inputs_for_generation
self.prepare_inputs_for_generation = self.base_model.prepare_inputs_for_generation
yield
finally:
self.forward = old_forward
self.prepare_inputs_for_generation = old_prepare_inputs_for_generation
elif self.peft_config[self.active_adapter].is_adaption_prompt:
try:
self.base_model.disable_adapter_layers()
yield
finally:
self.base_model.enable_adapter_layers()
else: # LoRA, LoHa, etc.
model_status = self.get_model_status()
if model_status.enabled == "irregular":
warnings.warn(
"The model contains some adapter layers that are enabled and others that are disabled. "
"This is most likely unintentional. After exiting the disable_adapter context, all adapters "
"will be enabled"
)
try:
self.base_model.disable_adapter_layers()
yield
finally:
if model_status.enabled is not False:
# model_status.enabled is `True` or `"irregular"`
self.base_model.enable_adapter_layers()
def get_base_model(self) -> torch.nn.Module:
"""
Returns the base model.
"""
return (
self.base_model
if (self.active_peft_config.is_prompt_learning or self.peft_type == PeftType.POLY)
else self.base_model.model
)
def add_adapter(self, adapter_name: str, peft_config: PeftConfig) -> None:
"""
Add an adapter to the model based on the passed configuration.
This adapter is not trained. To load a trained adapter, check out [`PeftModel.load_adapter`].
The name for the new adapter should be unique.
The new adapter is not automatically set as the active adapter. Use [`PeftModel.set_adapter`] to set the active
adapter.
Args:
adapter_name (`str`):
The name of the adapter to be added.
peft_config ([`PeftConfig`]):
The configuration of the adapter to be added.
"""
if peft_config.peft_type != self.peft_type:
raise ValueError(
f"Cannot combine adapters with different peft types. "
f"Found {self.peft_type} and {peft_config.peft_type}."
)
try:
if peft_config.is_prompt_learning:
self.peft_config[adapter_name] = peft_config
if hasattr(self.config, "to_dict"):
dict_config = self.config.to_dict()
else:
dict_config = self.config
peft_config = _prepare_prompt_learning_config(peft_config, dict_config)
self._setup_prompt_encoder(adapter_name)
elif peft_config.is_adaption_prompt:
self.base_model.add_adapter(adapter_name, peft_config)
else:
self.peft_config[adapter_name] = peft_config
self.base_model.inject_adapter(self.base_model.model, adapter_name)
except Exception: # something went wrong, roll back
if adapter_name in self.peft_config:
del self.peft_config[adapter_name]
raise
self.set_additional_trainable_modules(peft_config, adapter_name)
def set_additional_trainable_modules(self, peft_config, adapter_name):
if getattr(peft_config, "modules_to_save", None) is not None:
if self.modules_to_save is None:
self.modules_to_save = set(peft_config.modules_to_save)
else:
self.modules_to_save.update(peft_config.modules_to_save)
_set_trainable(self, adapter_name) # this may add a new ModulesToSaveWrapper
def get_layer_status(self) -> list[TunerLayerStatus]:
"""Get the status of each adapter layer in the model.
This method returns a list of `TunerLayerStatus` dataclass instances, each of which contains the following
attributes:
- `name` (`str`):
The name of the adapter layer, e.g. `model.encoder.block.0.layer.0.SelfAttention.q`.
- `module_type` (`str`):
The type of the adapter layer, e.g. `lora.Linear`.
- `enabled` (`bool`):
Whether the adapter layer is enabled.
- `active_adapters` (`list[str]`):
The names of the active adapters, if any, e.g. `["default"]`.
- `merged_adapters` (`list[str]`):
The names of the merged adapters, if any, e.g. `["default"]`.
- `available_adapters` (`list[str]`):
The names of the available adapters, e.g. `["default"]`.
Args:
model ([`~PeftModel`]):
The model to get the adapter layer status from.
Returns:
list[`peft.peft_model.TunerLayerStatus`]:
A list of dataclasses, each containing the status of the corresponding adapter layer.
"""
return get_layer_status(self)
def get_model_status(self) -> TunerModelStatus:
"""Get the status of tuners of the model.
This method returns a `TunerModelStatus` dataclass instance, which contains the following attributes:
- `base_model_type` (`str`):
The type of the base model, e.g. `T5Model`.
- `adapter_model_type` (`str`):
The type of the adapter model, e.g. `LoraModel`.
- `peft_types` (`dict[str, str]`):
The mapping of adapter name to adapter type, e.g. `{"default": "LORA"}`.
- `trainable_params` (`int`):
The number of trainable parameters in the model.
- `total_params` (`int`):
The total number of parameters in the model.
- `num_adapter_layers` (`int`):
The number of adapter layers in the model.
- `enabled` (`bool`, `Literal["irregular"]`):
Whether all adapter layers are enabled. If some are enabled and some are not, this will be `"irregular"`.
This means that your model is in an inconsistent state and might not work as expected.
- `active_adapters` (`list[str]`, `Literal["irregular"]`):
The names of the active adapters. If the active adapters are not consistent across all layers, this will be
`"irregular"`, which means that your model is in an inconsistent state and might not work as expected.
- `merged_adapters` (`list[str]`, `Literal["irregular"]`):
The names of the merged adapters. If the merged adapters are not consistent across all layers, this will be
`"irregular"`, which means that your model is in an inconsistent state and might not work as expected.
- `available_adapters` (`list[str]`):
The names of the available adapters, e.g. `["default"]`.
Args:
model ([`~PeftModel`]):
The model to get the adapter layer status from.
Returns:
`peft.peft_model.TunerModelStatus`:
A dataclass containing the status of the model.
"""
return get_model_status(self)
@classmethod
def _split_kwargs(cls, kwargs: dict[str, Any]):
_kwargs_not_in_hf_hub_download_signature = ("use_auth_token",)
hf_hub_download_kwargs = {}
other_kwargs = {}
for key, value in kwargs.items():
if key in inspect.signature(hf_hub_download).parameters or key in _kwargs_not_in_hf_hub_download_signature:
hf_hub_download_kwargs[key] = value
else:
other_kwargs[key] = value
return hf_hub_download_kwargs, other_kwargs
def _update_offload(self, offload_index: dict[str, dict[str, str]], adapters_weights: dict[str, torch.tensor]):
"""
Update the offload_index and safetensors files for loading and mergine PeftModels with disk-offloaded modules.
Args:
offload_index (Dict[str: str]):
Dictionary of disk-offloaded modules with their metadata and safetensors filenames
adapters_weights (Dict[str: torch.tensor]):
Dictionary of Peft adapter module names and weights
"""
if not offload_index:
return offload_index
prefix = "base_model.model."
# rename offload index weight and model names
adapter_names = list(self.peft_config.keys())
for adapter_name in adapter_names:
keys = list(offload_index.keys())
block_id = keys[0].split(".")[0] + "." # for writing safetensors key,
# replace original offload index keys with PeftModel keys
for key in keys:
suffix_pos = key.rfind(".")
extended_prefix = prefix + key[:suffix_pos]
module = dict(self.named_modules())[extended_prefix]
if isinstance(module, BaseTunerLayer):
new_key = prefix + key[:suffix_pos] + ".base_layer" + key[suffix_pos:]
else:
new_key = prefix + key
offload_index[key]["weight_name"] = new_key
offload_index[new_key] = offload_index[key]
del offload_index[key]
files_seen = set()
# rename safetensors for dispatch
for new_key in list(offload_index.keys()):
fname = offload_index[new_key]["safetensors_file"]
# make a new file name
new_fname_list = list(fname.split(os.sep))
for i, name in enumerate(new_fname_list):
if "--" in name:
new_fname_list[i] += "-peft"
break
new_fname = os.path.join(*new_fname_list)
if fname in files_seen:
continue
safe_dict = {}
with safe_open(fname, framework="pt") as f:
for safe_key in f.keys():
safe_tensor = f.get_tensor(safe_key)
metadata = f.metadata()
suffix_pos = safe_key.rfind(".")
extended_prefix = prefix + block_id + safe_key[:suffix_pos]
safe_module = dict(self.named_modules())[extended_prefix]
if isinstance(safe_module, BaseTunerLayer):
final_key = extended_prefix + ".base_layer" + safe_key[suffix_pos:]
lora_dict = {key: val for key, val in adapters_weights.items() if extended_prefix in key}
# add LoRA keys and values to disk offload
for lora_key, lora_val in lora_dict.items():
divide = lora_key.rfind(".")
new_key = lora_key[:divide] + f".{adapter_name}" + lora_key[divide:]
safe_dict[new_key] = lora_val
else:
final_key = prefix + block_id + safe_key
safe_dict[final_key] = safe_tensor
files_seen.add(new_fname)
# avoid overwriting original safetensors
for key in safe_dict.keys():
offload_index[key] = {"safetensors_file": new_fname, "weight_name": key}
base_name = os.path.dirname(new_fname)
if not os.path.exists(base_name):
os.makedirs(base_name)
safe_save_file(safe_dict, new_fname, metadata=metadata)
def load_adapter(
self,
model_id: str,
adapter_name: str,
is_trainable: bool = False,
torch_device: Optional[str] = None,
**kwargs: Any,
):
"""
Load a trained adapter into the model.
The name for the new adapter should be unique.
The new adapter is not automatically set as the active adapter. Use [`PeftModel.set_adapter`] to set the active
adapter.
Args:
adapter_name (`str`):
The name of the adapter to be added.
peft_config ([`PeftConfig`]):
The configuration of the adapter to be added.
is_trainable (`bool`, *optional*, defaults to `False`):
Whether the adapter should be trainable or not. If `False`, the adapter will be frozen and can only be
used for inference.
torch_device (`str`, *optional*, defaults to None):
The device to load the adapter on. If `None`, the device will be inferred.
kwargs: (`optional`):
Additional arguments to modify the way the adapter is loaded, e.g. the token for Hugging Face Hub.
"""
from .mapping import PEFT_TYPE_TO_CONFIG_MAPPING
hf_hub_download_kwargs, kwargs = self._split_kwargs(kwargs)
if torch_device is None:
torch_device = infer_device()
if adapter_name not in self.peft_config:
# load the config
peft_config = PEFT_TYPE_TO_CONFIG_MAPPING[
PeftConfig._get_peft_type(
model_id,
**hf_hub_download_kwargs,
)
].from_pretrained(
model_id,
**hf_hub_download_kwargs,
)
if peft_config.is_prompt_learning and is_trainable:
raise ValueError("Cannot set a prompt learning adapter to trainable when loading pretrained adapter.")
else:
peft_config.inference_mode = not is_trainable
self.add_adapter(adapter_name, peft_config)
adapters_weights = load_peft_weights(model_id, device=torch_device, **hf_hub_download_kwargs)
# load the weights into the model
ignore_mismatched_sizes = kwargs.get("ignore_mismatched_sizes", False)
load_result = set_peft_model_state_dict(
self, adapters_weights, adapter_name=adapter_name, ignore_mismatched_sizes=ignore_mismatched_sizes
)
if (
(getattr(self, "hf_device_map", None) is not None)
and (len(set(self.hf_device_map.values()).intersection({"cpu", "disk"})) > 0)
and len(self.peft_config) == 1
):
device_map = kwargs.get("device_map", "auto")
max_memory = kwargs.get("max_memory", None)
offload_dir = kwargs.get("offload_folder", None)
offload_index = kwargs.get("offload_index", None)
dispatch_model_kwargs = {}
# Safety checker for previous `accelerate` versions
# `offload_index` was introduced in https://github.com/huggingface/accelerate/pull/873/
if "offload_index" in inspect.signature(dispatch_model).parameters:
dispatch_model_kwargs["offload_index"] = offload_index
no_split_module_classes = self._no_split_modules
if device_map != "sequential":
max_memory = get_balanced_memory(
self,
max_memory=max_memory,
no_split_module_classes=no_split_module_classes,
low_zero=(device_map == "balanced_low_0"),
)
if isinstance(device_map, str):
device_map = infer_auto_device_map(
self, max_memory=max_memory, no_split_module_classes=no_split_module_classes
)
self._update_offload(offload_index, adapters_weights)
dispatch_model_kwargs["offload_index"] = offload_index
dispatch_model(
self,
device_map=device_map,
offload_dir=offload_dir,
**dispatch_model_kwargs,
)
hook = AlignDevicesHook(io_same_device=True)
if self.peft_config[adapter_name].is_prompt_learning:
remove_hook_from_submodules(self.prompt_encoder)
add_hook_to_module(self.get_base_model(), hook)
# Set model in evaluation mode to deactivate Dropout modules by default
if not is_trainable:
self.eval()
return load_result
def set_adapter(self, adapter_name: str) -> None:
"""
Sets the active adapter.
Only one adapter can be active at a time.
Additionally, this function will set the specified adapter to trainable (i.e., requires_grad=True). If this is
not desired, use the following code.
```py
>>> for name, param in model_peft.named_parameters():
... if ...: # some check on name (ex. if 'lora' in name)
... param.requires_grad = False
```
Args:
adapter_name (`str`):
The name of the adapter to be set as active. The adapter must be loaded first.
"""
if adapter_name not in self.peft_config:
raise ValueError(f"Adapter {adapter_name} not found.")
self.active_adapter = adapter_name
if not self.peft_config[adapter_name].is_prompt_learning:
self.base_model.set_adapter(adapter_name)
_set_adapter(self, adapter_name)
@property
def base_model_torch_dtype(self):
return getattr(self.base_model, "dtype", None)
@property
def active_peft_config(self):
return self.peft_config[self.active_adapter]
def create_or_update_model_card(self, output_dir: str):
"""
Updates or create model card to include information about peft:
1. Adds `peft` library tag
2. Adds peft version
3. Adds base model info
4. Adds quantization information if it was used
"""
filename = os.path.join(output_dir, "README.md")
card = ModelCard.load(filename) if os.path.exists(filename) else ModelCard.from_template(ModelCardData())
card.data["library_name"] = "peft"
model_config = getattr(self, "config", None)
if hasattr(model_config, "to_dict"):
model_config = model_config.to_dict()
if model_config is not None and "_name_or_path" in model_config:
card.data["base_model"] = model_config["_name_or_path"]
lines = card.text.splitlines()
quantization_config = None
if hasattr(model_config, "quantization_config"):
quantization_config = self.config.quantization_config.to_dict()
training_config_text = ""
quantization_prefix = "The following `bitsandbytes` quantization config was used during training:"
# Adds quantization information if it was used
if quantization_config is not None:
training_config_text += f"\n{quantization_prefix}\n"
training_config_text += "\n".join([f"- {name}: {value}" for name, value in quantization_config.items()])
training_config_text += "\n"
training_procedure_heading = "## Training procedure"
if quantization_prefix not in lines and bool(training_config_text):
if training_procedure_heading in lines:
lines.insert(lines.index(training_procedure_heading) + 2, training_config_text)
else:
lines.append(f"{training_procedure_heading}\n{training_config_text}")
# Adds peft version
framework_block_heading = "### Framework versions"
if f"- PEFT {__version__}" not in lines:
if framework_block_heading in lines:
lines.insert(lines.index(framework_block_heading) + 2, f"- PEFT {__version__}")
else:
lines.append(f"{framework_block_heading}\n\n- PEFT {__version__}")
card.text = "\n".join(lines)
card.save(filename)
class PeftModelForSequenceClassification(PeftModel):
"""
Peft model for sequence classification tasks.
Args:
model ([`~transformers.PreTrainedModel`]): Base transformer model.
peft_config ([`PeftConfig`]): Peft config.
**Attributes**:
- **config** ([`~transformers.PretrainedConfig`]) -- The configuration object of the base model.
- **cls_layer_name** (`str`) -- The name of the classification layer.
Example:
```py
>>> from transformers import AutoModelForSequenceClassification
>>> from peft import PeftModelForSequenceClassification, get_peft_config
>>> config = {
... "peft_type": "PREFIX_TUNING",
... "task_type": "SEQ_CLS",
... "inference_mode": False,
... "num_virtual_tokens": 20,
... "token_dim": 768,
... "num_transformer_submodules": 1,
... "num_attention_heads": 12,
... "num_layers": 12,
... "encoder_hidden_size": 768,
... "prefix_projection": False,
... "postprocess_past_key_value_function": None,
... }
>>> peft_config = get_peft_config(config)
>>> model = AutoModelForSequenceClassification.from_pretrained("bert-base-cased")
>>> peft_model = PeftModelForSequenceClassification(model, peft_config)
>>> peft_model.print_trainable_parameters()
trainable params: 370178 || all params: 108680450 || trainable%: 0.3406113979101117
```
"""
def __init__(self, model: torch.nn.Module, peft_config: PeftConfig, adapter_name: str = "default") -> None:
super().__init__(model, peft_config, adapter_name)
classifier_module_names = ["classifier", "score"]
if self.modules_to_save is None:
self.modules_to_save = set(classifier_module_names)
else:
self.modules_to_save.update(classifier_module_names)
if hasattr(peft_config, "modules_to_save"):
if peft_config.modules_to_save is None:
peft_config.modules_to_save = classifier_module_names[:]
else:
peft_config.modules_to_save.extend(classifier_module_names)
for name, _ in self.base_model.named_children():
if any(module_name in name for module_name in self.modules_to_save):
self.cls_layer_name = name
break
# to make sure classifier layer is trainable; this may add a new ModulesToSaveWrapper
_set_trainable(self, adapter_name)
def add_adapter(self, adapter_name: str, peft_config: PeftConfig) -> None:
"""
Add an adapter to the model based on the passed configuration.
This adapter is not trained. To load a trained adapter, check out [`PeftModel.load_adapter`].
The name for the new adapter should be unique.
The new adapter is not automatically set as the active adapter. Use [`PeftModel.set_adapter`] to set the active
adapter.
Args:
adapter_name (`str`):
The name of the adapter to be added.
peft_config ([`PeftConfig`]):
The configuration of the adapter to be added.
"""
# ensure that additional adapters also add the classifier layer to modules_to_save
if hasattr(peft_config, "modules_to_save"):
classifier_module_names = ["classifier", "score"]
if peft_config.modules_to_save is None:
peft_config.modules_to_save = classifier_module_names[:]
else:
peft_config.modules_to_save.extend(classifier_module_names)
return super().add_adapter(adapter_name, peft_config)
def forward(
self,
input_ids=None,
attention_mask=None,
inputs_embeds=None,
labels=None,
output_attentions=None,
output_hidden_states=None,
return_dict=None,
task_ids=None,
**kwargs,
):
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
peft_config = self.active_peft_config
if not peft_config.is_prompt_learning:
with self._enable_peft_forward_hooks(**kwargs):
kwargs = {k: v for k, v in kwargs.items() if k not in self.special_peft_forward_args}
if peft_config.peft_type == PeftType.POLY:
kwargs["task_ids"] = task_ids
return self.base_model(
input_ids=input_ids,
attention_mask=attention_mask,
inputs_embeds=inputs_embeds,
labels=labels,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
**kwargs,
)
batch_size = _get_batch_size(input_ids, inputs_embeds)
if attention_mask is not None:
# concat prompt attention mask
prefix_attention_mask = torch.ones(batch_size, peft_config.num_virtual_tokens).to(attention_mask.device)
attention_mask = torch.cat((prefix_attention_mask, attention_mask), dim=1)
if kwargs.get("position_ids", None) is not None:
warnings.warn("Position ids are not supported for parameter efficient tuning. Ignoring position ids.")
kwargs["position_ids"] = None
kwargs.update(
{
"attention_mask": attention_mask,
"labels": labels,
"output_attentions": output_attentions,
"output_hidden_states": output_hidden_states,
"return_dict": return_dict,
}
)
if peft_config.peft_type == PeftType.PREFIX_TUNING:
return self._prefix_tuning_forward(input_ids=input_ids, **kwargs)
else:
if kwargs.get("token_type_ids", None) is not None:
kwargs["token_type_ids"] = torch.cat(
(
torch.zeros(batch_size, peft_config.num_virtual_tokens).to(self.word_embeddings.weight.device),
kwargs["token_type_ids"],
),
dim=1,
).long()
if inputs_embeds is None:
inputs_embeds = self.word_embeddings(input_ids)
prompts = self.get_prompt(batch_size=batch_size, task_ids=task_ids)
prompts = prompts.to(inputs_embeds.dtype)
inputs_embeds = torch.cat((prompts, inputs_embeds), dim=1)
return self.base_model(inputs_embeds=inputs_embeds, **kwargs)
def _prefix_tuning_forward(
self,
input_ids=None,
attention_mask=None,
inputs_embeds=None,
labels=None,
output_attentions=None,
output_hidden_states=None,
return_dict=None,
**kwargs,
):
batch_size = _get_batch_size(input_ids, inputs_embeds)
past_key_values = self.get_prompt(batch_size)
fwd_params = list(inspect.signature(self.base_model.forward).parameters.keys())
kwargs.update(
{
"input_ids": input_ids,
"attention_mask": attention_mask,
"inputs_embeds": inputs_embeds,
"output_attentions": output_attentions,
"output_hidden_states": output_hidden_states,
"return_dict": return_dict,
"past_key_values": past_key_values,
}
)
if "past_key_values" in fwd_params:
return self.base_model(labels=labels, **kwargs)
else:
transformer_backbone_name = self.base_model.get_submodule(self.transformer_backbone_name)
fwd_params = list(inspect.signature(transformer_backbone_name.forward).parameters.keys())
if "past_key_values" not in fwd_params:
raise ValueError("Model does not support past key values which are required for prefix tuning.")
outputs = transformer_backbone_name(**kwargs)
pooled_output = outputs[1] if len(outputs) > 1 else outputs[0]
if "dropout" in [name for name, _ in list(self.base_model.named_children())]:
pooled_output = self.base_model.dropout(pooled_output)
logits = self.base_model.get_submodule(self.cls_layer_name)(pooled_output)
loss = None
if labels is not None:
if self.config.problem_type is None:
if self.base_model.num_labels == 1:
self.config.problem_type = "regression"
elif self.base_model.num_labels > 1 and (labels.dtype == torch.long or labels.dtype == torch.int):
self.config.problem_type = "single_label_classification"
else:
self.config.problem_type = "multi_label_classification"
if self.config.problem_type == "regression":
loss_fct = MSELoss()
if self.base_model.num_labels == 1:
loss = loss_fct(logits.squeeze(), labels.squeeze())
else:
loss = loss_fct(logits, labels)
elif self.config.problem_type == "single_label_classification":
loss_fct = CrossEntropyLoss()
loss = loss_fct(logits.view(-1, self.base_model.num_labels), labels.view(-1))
elif self.config.problem_type == "multi_label_classification":
loss_fct = BCEWithLogitsLoss()
loss = loss_fct(logits, labels)
if not return_dict:
output = (logits,) + outputs[2:]
return ((loss,) + output) if loss is not None else output
return SequenceClassifierOutput(
loss=loss,
logits=logits,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
)
class PeftModelForCausalLM(PeftModel):
"""
Peft model for causal language modeling.
Args:
model ([`~transformers.PreTrainedModel`]): Base transformer model.
peft_config ([`PeftConfig`]): Peft config.
Example:
```py
>>> from transformers import AutoModelForCausalLM
>>> from peft import PeftModelForCausalLM, get_peft_config
>>> config = {
... "peft_type": "PREFIX_TUNING",
... "task_type": "CAUSAL_LM",
... "inference_mode": False,
... "num_virtual_tokens": 20,
... "token_dim": 1280,
... "num_transformer_submodules": 1,
... "num_attention_heads": 20,
... "num_layers": 36,
... "encoder_hidden_size": 1280,
... "prefix_projection": False,
... "postprocess_past_key_value_function": None,
... }
>>> peft_config = get_peft_config(config)
>>> model = AutoModelForCausalLM.from_pretrained("gpt2-large")
>>> peft_model = PeftModelForCausalLM(model, peft_config)
>>> peft_model.print_trainable_parameters()
trainable params: 1843200 || all params: 775873280 || trainable%: 0.23756456724479544
```
"""
def __init__(self, model: torch.nn.Module, peft_config: PeftConfig, adapter_name: str = "default") -> None:
super().__init__(model, peft_config, adapter_name)
self.base_model_prepare_inputs_for_generation = self.base_model.prepare_inputs_for_generation
def forward(
self,
input_ids=None,
attention_mask=None,
inputs_embeds=None,
labels=None,
output_attentions=None,
output_hidden_states=None,
return_dict=None,
task_ids=None,
**kwargs,
):
peft_config = self.active_peft_config
if not peft_config.is_prompt_learning:
if self.base_model.config.model_type == "mpt":
if inputs_embeds is not None:
raise AssertionError("forward in MPTForCausalLM does not support inputs_embeds")
return self.base_model(
input_ids=input_ids,
attention_mask=attention_mask,
labels=labels,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
**kwargs,
)
if peft_config.peft_type == PeftType.POLY:
kwargs["task_ids"] = task_ids
with self._enable_peft_forward_hooks(**kwargs):
kwargs = {k: v for k, v in kwargs.items() if k not in self.special_peft_forward_args}
return self.base_model(
input_ids=input_ids,
attention_mask=attention_mask,
inputs_embeds=inputs_embeds,
labels=labels,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
**kwargs,
)
batch_size = _get_batch_size(input_ids, inputs_embeds)
if attention_mask is not None:
# concat prompt attention mask
prefix_attention_mask = torch.ones(batch_size, peft_config.num_virtual_tokens).to(attention_mask.device)
attention_mask = torch.cat((prefix_attention_mask, attention_mask), dim=1)
if kwargs.get("position_ids", None) is not None:
warnings.warn("Position ids are not supported for parameter efficient tuning. Ignoring position ids.")
kwargs["position_ids"] = None
if kwargs.get("token_type_ids", None) is not None:
warnings.warn("Token type ids are not supported for parameter efficient tuning. Ignoring token type ids")
kwargs["token_type_ids"] = None
kwargs.update(
{
"attention_mask": attention_mask,
"labels": labels,
"output_attentions": output_attentions,
"output_hidden_states": output_hidden_states,
"return_dict": return_dict,
}
)
if peft_config.peft_type == PeftType.PREFIX_TUNING:
past_key_values = self.get_prompt(batch_size)
return self.base_model(
input_ids=input_ids, inputs_embeds=inputs_embeds, past_key_values=past_key_values, **kwargs
)
else:
if inputs_embeds is None:
inputs_embeds = self.word_embeddings(input_ids)
# concat prompt labels
if labels is not None:
prefix_labels = torch.full((batch_size, peft_config.num_virtual_tokens), -100).to(labels.device)
kwargs["labels"] = torch.cat((prefix_labels, labels), dim=1)
prompts = self.get_prompt(batch_size=batch_size, task_ids=task_ids)
prompts = prompts.to(inputs_embeds.dtype)
inputs_embeds = torch.cat((prompts, inputs_embeds), dim=1)
return self.base_model(inputs_embeds=inputs_embeds, **kwargs)
def generate(self, *args, **kwargs):
peft_config = self.active_peft_config
self.base_model.prepare_inputs_for_generation = self.prepare_inputs_for_generation
if hasattr(self.base_model, "model"):
self.base_model.model.generation_config = self.generation_config
else:
self.base_model.generation_config = self.generation_config
try:
if not peft_config.is_prompt_learning:
with self._enable_peft_forward_hooks(*args, **kwargs):
kwargs = {k: v for k, v in kwargs.items() if k not in self.special_peft_forward_args}
outputs = self.base_model.generate(*args, **kwargs)
else:
outputs = self.base_model.generate(**kwargs)
except:
self.base_model.prepare_inputs_for_generation = self.base_model_prepare_inputs_for_generation
raise
else:
self.base_model.prepare_inputs_for_generation = self.base_model_prepare_inputs_for_generation
return outputs
def prepare_inputs_for_generation(self, *args, task_ids: Optional[torch.Tensor] = None, **kwargs):
peft_config = self.active_peft_config
model_kwargs = self.base_model_prepare_inputs_for_generation(*args, **kwargs)
# https://github.com/huggingface/transformers/pull/26681/ introduced new cache format
# for some architectures which requires a special fix for prompt tuning etc.
# TODO: starting with transformers 4.38, all architectures should support caching.
uses_transformers_4_38 = packaging.version.parse(transformers.__version__) >= packaging.version.parse("4.38.0")
uses_transformers_4_36 = packaging.version.parse(transformers.__version__) >= packaging.version.parse("4.36.0")
transformers_new_cache_archs = ["llama", "mistral", "persimmon", "phi"]
uses_cache = uses_transformers_4_38 or (
uses_transformers_4_36 and self.base_model.config.model_type in transformers_new_cache_archs
)
if peft_config.peft_type == PeftType.POLY:
model_kwargs["task_ids"] = task_ids
if peft_config.is_prompt_learning:
if uses_cache and (model_kwargs["past_key_values"] is not None):
# change in the logic of `prepare_inputs_for_generation` makes the below code necessary
# In prompt learning methods, past key values are longer when compared to the `input_ids`.
# As such only consider the last input ids in the autogressive generation phase.
if model_kwargs["past_key_values"][0][0].shape[-2] >= model_kwargs["input_ids"].shape[1]:
model_kwargs["input_ids"] = model_kwargs["input_ids"][:, -1:]
if model_kwargs.get("attention_mask", None) is not None:
size = model_kwargs["input_ids"].shape[0], peft_config.num_virtual_tokens
prefix_attention_mask = torch.ones(size).to(model_kwargs["input_ids"].device)
model_kwargs["attention_mask"] = torch.cat(
(prefix_attention_mask, model_kwargs["attention_mask"]), dim=1
)
if model_kwargs.get("position_ids", None) is not None:
warnings.warn("Position ids are not supported for parameter efficient tuning. Ignoring position ids.")
model_kwargs["position_ids"] = None
if kwargs.get("token_type_ids", None) is not None:
warnings.warn(
"Token type ids are not supported for parameter efficient tuning. Ignoring token type ids"
)
kwargs["token_type_ids"] = None
if model_kwargs["past_key_values"] is None and peft_config.peft_type == PeftType.PREFIX_TUNING:
past_key_values = self.get_prompt(batch_size=model_kwargs["input_ids"].shape[0])
model_kwargs["past_key_values"] = past_key_values
else:
if model_kwargs["past_key_values"] is None:
inputs_embeds = self.word_embeddings(model_kwargs["input_ids"])
prompts = self.get_prompt(batch_size=model_kwargs["input_ids"].shape[0], task_ids=task_ids)
prompts = prompts.to(inputs_embeds.dtype)
model_kwargs["inputs_embeds"] = torch.cat((prompts, inputs_embeds), dim=1)
model_kwargs["input_ids"] = None
# For transformers>=4.38.0 - for some architectures such as Llama, `cache_position` is
# passed in the forward pass to keep track of the position ids of the cache. We have to
# pop that from `model_kwargs` as `cache_position` is properly created by the model, using the passed
# `inputs_embeds`: https://github.com/huggingface/transformers/blob/593230f0a1150ea9c0477b9d859f25daf73c8c33/src/transformers/models/llama/modeling_llama.py#L956
_ = model_kwargs.pop("cache_position", None)
return model_kwargs
class PeftModelForSeq2SeqLM(PeftModel):
"""
Peft model for sequence-to-sequence language modeling.
Args:
model ([`~transformers.PreTrainedModel`]): Base transformer model.
peft_config ([`PeftConfig`]): Peft config.
Example:
```py
>>> from transformers import AutoModelForSeq2SeqLM
>>> from peft import PeftModelForSeq2SeqLM, get_peft_config
>>> config = {
... "peft_type": "LORA",
... "task_type": "SEQ_2_SEQ_LM",
... "inference_mode": False,
... "r": 8,
... "target_modules": ["q", "v"],
... "lora_alpha": 32,
... "lora_dropout": 0.1,
... "fan_in_fan_out": False,
... "enable_lora": None,
... "bias": "none",
... }
>>> peft_config = get_peft_config(config)
>>> model = AutoModelForSeq2SeqLM.from_pretrained("t5-base")
>>> peft_model = PeftModelForSeq2SeqLM(model, peft_config)
>>> peft_model.print_trainable_parameters()
trainable params: 884736 || all params: 223843584 || trainable%: 0.3952474242013566
```
"""
def __init__(self, model: torch.nn.Module, peft_config: PeftConfig, adapter_name: str = "default") -> None:
super().__init__(model, peft_config, adapter_name)
self.base_model_prepare_inputs_for_generation = self.base_model.prepare_inputs_for_generation
self.base_model_prepare_encoder_decoder_kwargs_for_generation = (
self.base_model._prepare_encoder_decoder_kwargs_for_generation
)
def forward(
self,
input_ids=None,
attention_mask=None,
inputs_embeds=None,
decoder_input_ids=None,
decoder_attention_mask=None,
decoder_inputs_embeds=None,
labels=None,
output_attentions=None,
output_hidden_states=None,
return_dict=None,
task_ids=None,
**kwargs,
):
peft_config = self.active_peft_config
if not peft_config.is_prompt_learning:
if peft_config.peft_type == PeftType.POLY:
kwargs["task_ids"] = task_ids
with self._enable_peft_forward_hooks(**kwargs):
kwargs = {k: v for k, v in kwargs.items() if k not in self.special_peft_forward_args}
return self.base_model(
input_ids=input_ids,
attention_mask=attention_mask,
inputs_embeds=inputs_embeds,
decoder_input_ids=decoder_input_ids,
decoder_attention_mask=decoder_attention_mask,
decoder_inputs_embeds=decoder_inputs_embeds,
labels=labels,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
**kwargs,
)
batch_size = _get_batch_size(input_ids, inputs_embeds)
if decoder_attention_mask is not None:
# concat prompt attention mask
prefix_attention_mask = torch.ones(batch_size, peft_config.num_virtual_tokens).to(
decoder_attention_mask.device
)
if peft_config.peft_type not in [PeftType.PROMPT_TUNING, PeftType.P_TUNING]:
decoder_attention_mask = torch.cat((prefix_attention_mask, decoder_attention_mask), dim=1)
if kwargs.get("position_ids", None) is not None:
warnings.warn("Position ids are not supported for parameter efficient tuning. Ignoring position ids.")
kwargs["position_ids"] = None
if kwargs.get("token_type_ids", None) is not None:
warnings.warn("Token type ids are not supported for parameter efficient tuning. Ignoring token type ids")
kwargs["token_type_ids"] = None
kwargs.update(
{
"attention_mask": attention_mask,
"decoder_attention_mask": decoder_attention_mask,
"labels": labels,
"output_attentions": output_attentions,
"output_hidden_states": output_hidden_states,
"return_dict": return_dict,
}
)
if peft_config.peft_type == PeftType.PREFIX_TUNING:
past_key_values = self.get_prompt(batch_size)
return self.base_model(
input_ids=input_ids,
decoder_input_ids=decoder_input_ids,
decoder_inputs_embeds=decoder_inputs_embeds,
past_key_values=past_key_values,
**kwargs,
)
elif peft_config.peft_type in [PeftType.PROMPT_TUNING, PeftType.P_TUNING]:
if inputs_embeds is None:
inputs_embeds = self.word_embeddings(input_ids)
if attention_mask is not None:
# concat prompt attention mask
prefix_attention_mask = torch.ones(batch_size, peft_config.num_virtual_tokens).to(
attention_mask.device
)
kwargs["attention_mask"] = torch.cat((prefix_attention_mask, attention_mask), dim=1)
prompts = self.get_prompt(batch_size=batch_size)
prompts = prompts.to(inputs_embeds.dtype)
inputs_embeds = torch.cat((prompts[:, : peft_config.num_virtual_tokens], inputs_embeds), dim=1)
return self.base_model(
inputs_embeds=inputs_embeds,
decoder_input_ids=decoder_input_ids,
decoder_inputs_embeds=decoder_inputs_embeds,
**kwargs,
)
else:
if inputs_embeds is None:
inputs_embeds = self.word_embeddings(input_ids)
if decoder_inputs_embeds is None and decoder_input_ids is None:
decoder_input_ids = shift_tokens_right(
labels, self.config.pad_token_id, self.config.decoder_start_token_id
)
decoder_inputs_embeds = self.word_embeddings(decoder_input_ids)
if attention_mask is not None:
# concat prompt attention mask
prefix_attention_mask = torch.ones(batch_size, peft_config.num_virtual_tokens).to(
attention_mask.device
)
kwargs["attention_mask"] = torch.cat((prefix_attention_mask, attention_mask), dim=1)
# concat prompt labels
if labels is not None:
if peft_config.num_transformer_submodules == 1:
kwargs["labels"] = labels
elif peft_config.num_transformer_submodules == 2:
prefix_labels = torch.full((batch_size, peft_config.num_virtual_tokens), -100).to(labels.device)
kwargs["labels"] = torch.cat((prefix_labels, labels), dim=1)
prompts = self.get_prompt(batch_size=batch_size, task_ids=task_ids)
prompts = prompts.to(inputs_embeds.dtype)
inputs_embeds = torch.cat((prompts[:, : peft_config.num_virtual_tokens], inputs_embeds), dim=1)
if peft_config.num_transformer_submodules == 1:
return self.base_model(inputs_embeds=inputs_embeds, **kwargs)
elif peft_config.num_transformer_submodules == 2:
decoder_inputs_embeds = torch.cat(
(prompts[:, peft_config.num_virtual_tokens :], decoder_inputs_embeds), dim=1
)
return self.base_model(
inputs_embeds=inputs_embeds, decoder_inputs_embeds=decoder_inputs_embeds, **kwargs
)
def generate(self, **kwargs):
peft_config = self.active_peft_config
self.base_model.prepare_inputs_for_generation = self.prepare_inputs_for_generation
self.base_model._prepare_encoder_decoder_kwargs_for_generation = (
self._prepare_encoder_decoder_kwargs_for_generation
)
try:
if not peft_config.is_prompt_learning:
with self._enable_peft_forward_hooks(**kwargs):
kwargs = {k: v for k, v in kwargs.items() if k not in self.special_peft_forward_args}
outputs = self.base_model.generate(**kwargs)
else:
if "input_ids" not in kwargs:
raise ValueError("input_ids must be provided for Peft model generation")
if kwargs.get("position_ids", None) is not None:
warnings.warn(
"Position ids are not supported for parameter efficient tuning. Ignoring position ids."
)
kwargs["position_ids"] = None
if kwargs.get("token_type_ids", None) is not None:
warnings.warn(
"Token type ids are not supported for parameter efficient tuning. Ignoring token type ids"
)
kwargs["token_type_ids"] = None
if peft_config.peft_type == PeftType.PREFIX_TUNING:
outputs = self.base_model.generate(**kwargs)
elif peft_config.peft_type in [
PeftType.PROMPT_TUNING,
PeftType.P_TUNING,
PeftType.MULTITASK_PROMPT_TUNING,
]:
kwargs = deepcopy(kwargs)
if "encoder_outputs" in kwargs:
del kwargs["encoder_outputs"]
warnings.warn(
"`encoder_outputs` should not be passed to `generate` when using prompt tuning. Ignoring it."
)
input_ids = kwargs.pop("input_ids")
inputs_embeds = self.word_embeddings(input_ids)
batch_size = inputs_embeds.shape[0]
prompts = self.get_prompt(batch_size=batch_size, task_ids=kwargs.pop("task_ids", None))
prompts = prompts.to(inputs_embeds.dtype)
inputs_embeds = torch.cat((prompts[:, : peft_config.num_virtual_tokens], inputs_embeds), dim=1)
kwargs["inputs_embeds"] = inputs_embeds
if "attention_mask" in kwargs:
prefix_attention_mask = torch.ones(batch_size, peft_config.num_virtual_tokens).to(
kwargs["attention_mask"].device
)
kwargs["attention_mask"] = torch.cat((prefix_attention_mask, kwargs["attention_mask"]), dim=1)
return self.base_model.generate(**kwargs)
else:
raise NotImplementedError
except:
self.base_model.prepare_inputs_for_generation = self.base_model_prepare_inputs_for_generation
self.base_model._prepare_encoder_decoder_kwargs_for_generation = (
self.base_model_prepare_encoder_decoder_kwargs_for_generation
)
raise
else:
self.base_model.prepare_inputs_for_generation = self.base_model_prepare_inputs_for_generation
self.base_model._prepare_encoder_decoder_kwargs_for_generation = (
self.base_model_prepare_encoder_decoder_kwargs_for_generation
)
return outputs
def prepare_inputs_for_generation(self, *args, task_ids: torch.Tensor = None, **kwargs):
peft_config = self.active_peft_config
model_kwargs = self.base_model_prepare_inputs_for_generation(*args, **kwargs)
if peft_config.peft_type == PeftType.POLY:
model_kwargs["task_ids"] = task_ids
if model_kwargs["past_key_values"] is None and peft_config.peft_type == PeftType.PREFIX_TUNING:
batch_size = model_kwargs["decoder_input_ids"].shape[0]
past_key_values = self.get_prompt(batch_size)
model_kwargs["past_key_values"] = past_key_values
return model_kwargs
class PeftModelForTokenClassification(PeftModel):
"""
Peft model for token classification tasks.
Args:
model ([`~transformers.PreTrainedModel`]): Base transformer model.
peft_config ([`PeftConfig`]): Peft config.
**Attributes**:
- **config** ([`~transformers.PretrainedConfig`]) -- The configuration object of the base model.
- **cls_layer_name** (`str`) -- The name of the classification layer.
Example:
```py
>>> from transformers import AutoModelForSequenceClassification
>>> from peft import PeftModelForTokenClassification, get_peft_config
>>> config = {
... "peft_type": "PREFIX_TUNING",
... "task_type": "TOKEN_CLS",
... "inference_mode": False,
... "num_virtual_tokens": 20,
... "token_dim": 768,
... "num_transformer_submodules": 1,
... "num_attention_heads": 12,
... "num_layers": 12,
... "encoder_hidden_size": 768,
... "prefix_projection": False,
... "postprocess_past_key_value_function": None,
... }
>>> peft_config = get_peft_config(config)
>>> model = AutoModelForTokenClassification.from_pretrained("bert-base-cased")
>>> peft_model = PeftModelForTokenClassification(model, peft_config)
>>> peft_model.print_trainable_parameters()
trainable params: 370178 || all params: 108680450 || trainable%: 0.3406113979101117
```
"""
def __init__(self, model: torch.nn.Module, peft_config: PeftConfig = None, adapter_name: str = "default") -> None:
super().__init__(model, peft_config, adapter_name)
classifier_module_names = ["classifier", "score"]
if self.modules_to_save is None:
self.modules_to_save = set(classifier_module_names)
else:
self.modules_to_save.update(classifier_module_names)
if hasattr(peft_config, "modules_to_save"):
if peft_config.modules_to_save is None:
peft_config.modules_to_save = classifier_module_names[:]
else:
peft_config.modules_to_save.extend(classifier_module_names)
for name, _ in self.base_model.named_children():
if any(module_name in name for module_name in self.modules_to_save):
self.cls_layer_name = name
break
# to make sure classifier layer is trainable; this may add a new ModulesToSaveWrapper
_set_trainable(self, adapter_name)
def add_adapter(self, adapter_name: str, peft_config: PeftConfig) -> None:
"""
Add an adapter to the model based on the passed configuration.
This adapter is not trained. To load a trained adapter, check out [`PeftModel.load_adapter`].
The name for the new adapter should be unique.
The new adapter is not automatically set as the active adapter. Use [`PeftModel.set_adapter`] to set the active
adapter.
Args:
adapter_name (`str`):
The name of the adapter to be added.
peft_config ([`PeftConfig`]):
The configuration of the adapter to be added.
"""
# ensure that additional adapters also add the classifier layer to modules_to_save
if hasattr(peft_config, "modules_to_save"):
classifier_module_names = ["classifier", "score"]
if peft_config.modules_to_save is None:
peft_config.modules_to_save = classifier_module_names[:]
else:
peft_config.modules_to_save.extend(classifier_module_names)
return super().add_adapter(adapter_name, peft_config)
def forward(
self,
input_ids=None,
attention_mask=None,
inputs_embeds=None,
labels=None,
output_attentions=None,
output_hidden_states=None,
return_dict=None,
task_ids=None,
**kwargs,
):
peft_config = self.active_peft_config
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
if not peft_config.is_prompt_learning:
with self._enable_peft_forward_hooks(**kwargs):
kwargs = {k: v for k, v in kwargs.items() if k not in self.special_peft_forward_args}
if peft_config.peft_type == PeftType.POLY:
kwargs["task_ids"] = task_ids
return self.base_model(
input_ids=input_ids,
attention_mask=attention_mask,
inputs_embeds=inputs_embeds,
labels=labels,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
**kwargs,
)
batch_size = _get_batch_size(input_ids, inputs_embeds)
if attention_mask is not None:
# concat prompt attention mask
prefix_attention_mask = torch.ones(batch_size, peft_config.num_virtual_tokens).to(attention_mask.device)
attention_mask = torch.cat((prefix_attention_mask, attention_mask), dim=1)
if kwargs.get("position_ids", None) is not None:
warnings.warn("Position ids are not supported for parameter efficient tuning. Ignoring position ids.")
kwargs["position_ids"] = None
kwargs.update(
{
"attention_mask": attention_mask,
"labels": labels,
"output_attentions": output_attentions,
"output_hidden_states": output_hidden_states,
"return_dict": return_dict,
}
)
if peft_config.peft_type == PeftType.PREFIX_TUNING:
return self._prefix_tuning_forward(input_ids=input_ids, **kwargs)
else:
if kwargs.get("token_type_ids", None) is not None:
kwargs["token_type_ids"] = torch.cat(
(
torch.zeros(batch_size, peft_config.num_virtual_tokens).to(self.word_embeddings.weight.device),
kwargs["token_type_ids"],
),
dim=1,
).long()
if inputs_embeds is None:
inputs_embeds = self.word_embeddings(input_ids)
prompts = self.get_prompt(batch_size=batch_size, task_ids=task_ids)
prompts = prompts.to(inputs_embeds.dtype)
inputs_embeds = torch.cat((prompts, inputs_embeds), dim=1)
return self.base_model(inputs_embeds=inputs_embeds, **kwargs)
def _prefix_tuning_forward(
self,
input_ids=None,
attention_mask=None,
inputs_embeds=None,
labels=None,
output_attentions=None,
output_hidden_states=None,
return_dict=None,
**kwargs,
):
batch_size = _get_batch_size(input_ids, inputs_embeds)
past_key_values = self.get_prompt(batch_size)
fwd_params = list(inspect.signature(self.base_model.forward).parameters.keys())
kwargs.update(
{
"input_ids": input_ids,
"attention_mask": attention_mask,
"inputs_embeds": inputs_embeds,
"output_attentions": output_attentions,
"output_hidden_states": output_hidden_states,
"return_dict": return_dict,
"past_key_values": past_key_values,
}
)
if "past_key_values" in fwd_params:
return self.base_model(labels=labels, **kwargs)
else:
transformer_backbone_name = self.base_model.get_submodule(self.transformer_backbone_name)
fwd_params = list(inspect.signature(transformer_backbone_name.forward).parameters.keys())
if "past_key_values" not in fwd_params:
raise ValueError("Model does not support past key values which are required for prefix tuning.")
outputs = transformer_backbone_name(**kwargs)
sequence_output = outputs[0]
if "dropout" in [name for name, _ in list(self.base_model.named_children())]:
sequence_output = self.base_model.dropout(sequence_output)
logits = self.base_model.get_submodule(self.cls_layer_name)(sequence_output)
loss = None
if labels is not None:
loss_fct = CrossEntropyLoss()
loss = loss_fct(logits.view(-1, self.num_labels), labels.view(-1))
if not return_dict:
output = (logits,) + outputs[2:]
return ((loss,) + output) if loss is not None else output
return TokenClassifierOutput(
loss=loss,
logits=logits,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
)
class PeftModelForQuestionAnswering(PeftModel):
"""
Peft model for extractive question answering.
Args:
model ([`~transformers.PreTrainedModel`]): Base transformer model.
peft_config ([`PeftConfig`]): Peft config.
**Attributes**:
- **config** ([`~transformers.PretrainedConfig`]) -- The configuration object of the base model.
- **cls_layer_name** (`str`) -- The name of the classification layer.
Example:
```py
>>> from transformers import AutoModelForQuestionAnswering
>>> from peft import PeftModelForQuestionAnswering, get_peft_config
>>> config = {
... "peft_type": "LORA",
... "task_type": "QUESTION_ANS",
... "inference_mode": False,
... "r": 16,
... "target_modules": ["query", "value"],
... "lora_alpha": 32,
... "lora_dropout": 0.05,
... "fan_in_fan_out": False,
... "bias": "none",
... }
>>> peft_config = get_peft_config(config)
>>> model = AutoModelForQuestionAnswering.from_pretrained("bert-base-cased")
>>> peft_model = PeftModelForQuestionAnswering(model, peft_config)
>>> peft_model.print_trainable_parameters()
trainable params: 592900 || all params: 108312580 || trainable%: 0.5473971721475013
```
"""
def __init__(self, model: torch.nn.Module, peft_config: PeftConfig, adapter_name: str = "default") -> None:
super().__init__(model, peft_config, adapter_name)
qa_module_names = ["qa_outputs"]
if self.modules_to_save is None:
self.modules_to_save = set(qa_module_names)
else:
self.modules_to_save.update(qa_module_names)
if hasattr(peft_config, "modules_to_save"):
if peft_config.modules_to_save is None:
peft_config.modules_to_save = qa_module_names[:]
else:
peft_config.modules_to_save.extend(qa_module_names)
for name, _ in self.base_model.named_children():
if any(module_name in name for module_name in self.modules_to_save):
self.cls_layer_name = name
break
# to make sure classifier layer is trainable; this may add a new ModulesToSaveWrapper
_set_trainable(self, adapter_name)
def add_adapter(self, adapter_name: str, peft_config: PeftConfig) -> None:
"""
Add an adapter to the model based on the passed configuration.
This adapter is not trained. To load a trained adapter, check out [`PeftModel.load_adapter`].
The name for the new adapter should be unique.
The new adapter is not automatically set as the active adapter. Use [`PeftModel.set_adapter`] to set the active
adapter.
Args:
adapter_name (`str`):
The name of the adapter to be added.
peft_config ([`PeftConfig`]):
The configuration of the adapter to be added.
"""
# ensure that additional adapters also add the classifier layer to modules_to_save
if hasattr(peft_config, "modules_to_save"):
qa_module_names = ["qa_outputs"]
if peft_config.modules_to_save is None:
peft_config.modules_to_save = qa_module_names[:]
else:
peft_config.modules_to_save.extend(qa_module_names)
return super().add_adapter(adapter_name, peft_config)
def forward(
self,
input_ids=None,
attention_mask=None,
token_type_ids=None,
position_ids=None,
inputs_embeds=None,
start_positions=None,
end_positions=None,
output_attentions=None,
output_hidden_states=None,
return_dict=None,
task_ids=None,
**kwargs,
):
peft_config = self.active_peft_config
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
if not peft_config.is_prompt_learning:
if peft_config.peft_type == PeftType.POLY:
kwargs["task_ids"] = task_ids
with self._enable_peft_forward_hooks(**kwargs):
kwargs = {k: v for k, v in kwargs.items() if k not in self.special_peft_forward_args}
return self.base_model(
input_ids=input_ids,
attention_mask=attention_mask,
inputs_embeds=inputs_embeds,
start_positions=start_positions,
end_positions=end_positions,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
**kwargs,
)
batch_size = _get_batch_size(input_ids, inputs_embeds)
if attention_mask is not None:
# concat prompt attention mask
prefix_attention_mask = torch.ones(batch_size, peft_config.num_virtual_tokens).to(attention_mask.device)
attention_mask = torch.cat((prefix_attention_mask, attention_mask), dim=1)
if kwargs.get("position_ids", None) is not None:
warnings.warn("Position ids are not supported for parameter efficient tuning. Ignoring position ids.")
kwargs["position_ids"] = None
kwargs.update(
{
"attention_mask": attention_mask,
"start_positions": start_positions,
"end_positions": end_positions,
"output_attentions": output_attentions,
"output_hidden_states": output_hidden_states,
"return_dict": return_dict,
}
)
if peft_config.peft_type == PeftType.PREFIX_TUNING:
return self._prefix_tuning_forward(input_ids=input_ids, **kwargs)
else:
if kwargs.get("token_type_ids", None) is not None:
kwargs["token_type_ids"] = torch.cat(
(
torch.zeros(batch_size, peft_config.num_virtual_tokens).to(self.word_embeddings.weight.device),
kwargs["token_type_ids"],
),
dim=1,
).long()
if inputs_embeds is None:
inputs_embeds = self.word_embeddings(input_ids)
prompts = self.get_prompt(batch_size=batch_size)
prompts = prompts.to(inputs_embeds.dtype)
inputs_embeds = torch.cat((prompts, inputs_embeds), dim=1)
return self.base_model(inputs_embeds=inputs_embeds, **kwargs)
def _prefix_tuning_forward(
self,
input_ids=None,
attention_mask=None,
inputs_embeds=None,
start_positions=None,
end_positions=None,
output_attentions=None,
output_hidden_states=None,
return_dict=None,
**kwargs,
):
batch_size = _get_batch_size(input_ids, inputs_embeds)
past_key_values = self.get_prompt(batch_size)
fwd_params = list(inspect.signature(self.base_model.forward).parameters.keys())
kwargs.update(
{
"input_ids": input_ids,
"attention_mask": attention_mask,
"inputs_embeds": inputs_embeds,
"output_attentions": output_attentions,
"output_hidden_states": output_hidden_states,
"return_dict": return_dict,
"past_key_values": past_key_values,
}
)
if "past_key_values" in fwd_params:
return self.base_model(start_positions=start_positions, end_positions=end_positions, **kwargs)
else:
transformer_backbone_name = self.base_model.get_submodule(self.transformer_backbone_name)
fwd_params = list(inspect.signature(transformer_backbone_name.forward).parameters.keys())
if "past_key_values" not in fwd_params:
raise ValueError("Model does not support past key values which are required for prefix tuning.")
outputs = transformer_backbone_name(**kwargs)
sequence_output = outputs[0]
if "dropout" in [name for name, _ in list(self.base_model.named_children())]:
sequence_output = self.base_model.dropout(sequence_output)
logits = self.base_model.get_submodule(self.cls_layer_name)(sequence_output)
start_logits, end_logits = logits.split(1, dim=-1)
start_logits = start_logits.squeeze(-1).contiguous()
end_logits = end_logits.squeeze(-1).contiguous()
total_loss = None
if start_positions is not None and end_positions is not None:
# If we are on multi-GPU, split add a dimension
if len(start_positions.size()) > 1:
start_positions = start_positions.squeeze(-1)
if len(end_positions.size()) > 1:
end_positions = end_positions.squeeze(-1)
# sometimes the start/end positions are outside our model inputs, we ignore these terms
ignored_index = start_logits.size(1)
start_positions = start_positions.clamp(0, ignored_index)
end_positions = end_positions.clamp(0, ignored_index)
loss_fct = CrossEntropyLoss(ignore_index=ignored_index)
start_loss = loss_fct(start_logits, start_positions)
end_loss = loss_fct(end_logits, end_positions)
total_loss = (start_loss + end_loss) / 2
if not return_dict:
output = (start_logits, end_logits) + outputs[2:]
return ((total_loss,) + output) if total_loss is not None else output
return QuestionAnsweringModelOutput(
loss=total_loss,
start_logits=start_logits,
end_logits=end_logits,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
)
class PeftModelForFeatureExtraction(PeftModel):
"""
Peft model for extracting features/embeddings from transformer models
Args:
model ([`~transformers.PreTrainedModel`]): Base transformer model.
peft_config ([`PeftConfig`]): Peft config.
**Attributes**:
- **config** ([`~transformers.PretrainedConfig`]) -- The configuration object of the base model.
Example:
```py
>>> from transformers import AutoModel
>>> from peft import PeftModelForFeatureExtraction, get_peft_config
>>> config = {
... "peft_type": "LORA",
... "task_type": "FEATURE_EXTRACTION",
... "inference_mode": False,
... "r": 16,
... "target_modules": ["query", "value"],
... "lora_alpha": 32,
... "lora_dropout": 0.05,
... "fan_in_fan_out": False,
... "bias": "none",
... }
>>> peft_config = get_peft_config(config)
>>> model = AutoModel.from_pretrained("bert-base-cased")
>>> peft_model = PeftModelForFeatureExtraction(model, peft_config)
>>> peft_model.print_trainable_parameters()
```
"""
def __init__(self, model: torch.nn.Module, peft_config: PeftConfig, adapter_name: str = "default"):
super().__init__(model, peft_config, adapter_name)
def forward(
self,
input_ids=None,
attention_mask=None,
inputs_embeds=None,
output_attentions=None,
output_hidden_states=None,
return_dict=None,
task_ids=None,
**kwargs,
):
peft_config = self.active_peft_config
if not peft_config.is_prompt_learning:
if peft_config.peft_type == PeftType.POLY:
kwargs["task_ids"] = task_ids
with self._enable_peft_forward_hooks(**kwargs):
kwargs = {k: v for k, v in kwargs.items() if k not in self.special_peft_forward_args}
return self.base_model(
input_ids=input_ids,
attention_mask=attention_mask,
inputs_embeds=inputs_embeds,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
**kwargs,
)
batch_size = _get_batch_size(input_ids, inputs_embeds)
if attention_mask is not None:
# concat prompt attention mask
prefix_attention_mask = torch.ones(batch_size, peft_config.num_virtual_tokens).to(attention_mask.device)
attention_mask = torch.cat((prefix_attention_mask, attention_mask), dim=1)
if kwargs.get("position_ids", None) is not None:
warnings.warn("Position ids are not supported for parameter efficient tuning. Ignoring position ids.")
kwargs["position_ids"] = None
if kwargs.get("token_type_ids", None) is not None:
warnings.warn("Token type ids are not supported for parameter efficient tuning. Ignoring token type ids")
kwargs["token_type_ids"] = None
kwargs.update(
{
"attention_mask": attention_mask,
"output_attentions": output_attentions,
"output_hidden_states": output_hidden_states,
"return_dict": return_dict,
}
)
if peft_config.peft_type == PeftType.PREFIX_TUNING:
past_key_values = self.get_prompt(batch_size)
return self.base_model(input_ids=input_ids, past_key_values=past_key_values, **kwargs)
else:
if inputs_embeds is None:
inputs_embeds = self.word_embeddings(input_ids)
prompts = self.get_prompt(batch_size=batch_size)
prompts = prompts.to(inputs_embeds.dtype)
inputs_embeds = torch.cat((prompts, inputs_embeds), dim=1)
return self.base_model(inputs_embeds=inputs_embeds, **kwargs)
@dataclass
class TunerLayerStatus:
name: str
module_type: str
enabled: bool
active_adapters: list[str]
merged_adapters: list[str]
requires_grad: dict[str, bool | Literal["irregular"]]
available_adapters: list[str]
def get_layer_status(model: torch.nn.Module) -> list[TunerLayerStatus]:
"""Get the status of each adapter layer in the model.
This function returns a list of `TunerLayerStatus` dataclass instances, each of which contains the following
attributes:
- `name` (`str`):
The name of the adapter layer, e.g. `model.encoder.block.0.layer.0.SelfAttention.q`.
- `module_type` (`str`):
The type of the adapter layer, e.g. `lora.Linear`.
- `enabled` (`bool`):
Whether the adapter layer is enabled.
- `active_adapters` (`list[str]`):
The names of the active adapters, if any, e.g. `["default"]`.
- `merged_adapters` (`list[str]`):
The names of the merged adapters, if any, e.g. `["default"]`.
- requires_grad : dict[str, bool | Literal["irregular"]]
The requires_grad status of the parameters for each adapter module. Ideally, it should be either `True` or
`False`. If the requires_grad status is not consistent across all parameters, the value will be set to
`"irregular"`.
- `available_adapters` (`list[str]`):
The names of the available adapters, e.g. `["default"]`.
Args:
model ([Union[`~PeftModel`, `~transformers.PreTrainedModel`, `nn.Module`]]):
The model to get the adapter layer status from.
Returns:
list[`peft.peft_model.TunerLayerStatus`]:
A list of dataclasses, each containing the status of the corresponding adapter layer.
"""
if isinstance(model, PeftModel):
base_model = model.base_model
if not isinstance(base_model, BaseTuner):
raise TypeError(
"get_layer_status() got an invalid PeftModel instance; prefix tuning and adaption prompt are not "
"supported."
)
else:
base_model = model
layer_status: list[TunerLayerStatus] = []
for name, module in base_model.named_modules():
if not isinstance(module, BaseTunerLayer):
continue
# determine if all submodules/parameters if this module require grad or not
mapping_requires_grad_list: dict[str, list[bool]] = collections.defaultdict(list)
for adapter_module_name in module.adapter_layer_names:
adapter_module = getattr(module, adapter_module_name)
if isinstance(adapter_module, torch.nn.ModuleDict):
for key, submodule in adapter_module.items():
for param in submodule.parameters():
mapping_requires_grad_list[key].append(param.requires_grad)
elif isinstance(adapter_module, torch.nn.ParameterDict):
for key, param in adapter_module.items():
mapping_requires_grad_list[key].append(param.requires_grad)
else:
# strange, we don't know how to handle this, ignore for now
pass
def check_irrgular(vals: list[bool]) -> bool | Literal["irregular"]:
if all(vals):
return True
if not any(vals):
return False
return "irregular"
requires_grad = {key: check_irrgular(vals) for key, vals in mapping_requires_grad_list.items()}
status = TunerLayerStatus(
name=name,
module_type=repr(module).partition("(")[0],
enabled=not module.disable_adapters,
active_adapters=module.active_adapters,
merged_adapters=module.merged_adapters,
requires_grad=requires_grad,
available_adapters=sorted(module._get_available_adapters()),
)
layer_status.append(status)
if not layer_status:
raise ValueError(
"No adapter layers found in the model, please ensure that it's a PEFT model or that you have PEFT adapters "
"injected in the model."
)
return layer_status
@dataclass
class TunerModelStatus:
base_model_type: str
adapter_model_type: str
peft_types: dict[str, str]
trainable_params: int
total_params: int
num_adapter_layers: int
enabled: bool | Literal["irregular"]
active_adapters: list[str] | Literal["irregular"]
merged_adapters: list[str] | Literal["irregular"]
requires_grad: dict[str, bool | Literal["irregular"]]
available_adapters: list[str]
def get_model_status(model: torch.nn.Module) -> TunerModelStatus:
"""Get the status of tuners of the model.
This function returns a `TunerModelStatus` dataclass instance, which contains the following attributes:
- `base_model_type` (`str`):
The type of the base model, e.g. `T5Model`.
- `adapter_model_type` (`str`):
The type of the adapter model, e.g. `LoraModel`.
- `peft_types` (`dict[str, str]`):
The mapping of adapter name to adapter type, e.g. `{"default": "LORA"}`.
- `trainable_params` (`int`):
The number of trainable parameters in the model.
- `total_params` (`int`):
The total number of parameters in the model.
- `num_adapter_layers` (`int`):
The number of adapter layers in the model.
- `enabled` (`bool`, `Literal["irregular"]`):
Whether all adapter layers are enabled. If some are enabled and some are not, this will be `"irregular"`. This
means that your model is in an inconsistent state and might not work as expected.
- `active_adapters` (`list[str]`, `Literal["irregular"]`):
The names of the active adapters. If the active adapters are not consistent across all layers, this will be
`"irregular"`, which means that your model is in an inconsistent state and might not work as expected.
- `merged_adapters` (`list[str]`, `Literal["irregular"]`):
The names of the merged adapters. If the merged adapters are not consistent across all layers, this will be
`"irregular"`, which means that your model is in an inconsistent state and might not work as expected.
- `requires_grad` (`dict[str, bool | Literal["irregular"]]`):
Whether for the given adapter, all adapter layers have `requires_grad` set to `True` or `False`. If there is a
mix, this will be set to `"irregular"`, which means that your model is in an inconsistent state and might not
work as expected.
- `available_adapters` (`list[str]`):
The names of the available adapters, e.g. `["default"]`.
Args:
model ([Union[`~PeftModel`, `~transformers.PreTrainedModel`, `nn.Module`]]):
The model to get the adapter layer status from.
Returns:
`peft.peft_model.TunerModelStatus`:
A dataclass containing the status of the model.
"""
if isinstance(model, PeftModel):
if not isinstance(model.base_model, BaseTuner):
raise TypeError(
"get_model_status() got an invalid PeftModel instance; prefix tuning and adaption prompt are not "
"supported."
)
base_model_type = model.get_base_model().__class__.__name__
trainable_params, total_params = model.get_nb_trainable_parameters()
base_model = model.base_model
peft_types = {key: str(config.peft_type).partition(".")[-1] for key, config in base_model.peft_config.items()}
adapter_model_type = base_model.__class__.__name__
elif isinstance(model, PreTrainedModel):
base_model_type = model.__class__.__name__
trainable_params, total_params = PeftModel.get_nb_trainable_parameters(model)
base_model = model
peft_types = {}
adapter_model_type = "None"
else:
base_model_type = "other"
trainable_params, total_params = PeftModel.get_nb_trainable_parameters(model)
base_model = model
peft_types = {}
adapter_model_type = "None"
layer_status = get_layer_status(model)
num_adapter_layers = len(layer_status)
enabled_set: set[bool] = {status.enabled for status in layer_status} # must be {True}, {False}, or {True, False}
enabled: bool | Literal["irregular"]
if len(enabled_set) == 1:
enabled = enabled_set.pop()
else:
enabled = "irregular"
available_adapters: list[str] = sorted(set().union(*(status.available_adapters for status in layer_status)))
# ideally, active adapters should be consistent across all layers of the model, but we cannot guarantee it
all_active_adapters: set[tuple[str, ...]] = {tuple(status.active_adapters) for status in layer_status}
active_adapters: list[str] | Literal["irregular"]
if not all_active_adapters:
active_adapters = []
elif len(all_active_adapters) == 1:
active_adapters = list(all_active_adapters.pop())
else:
active_adapters = "irregular"
# Here we determine what adapters are merged. This is not trivial because multiple adapters can be merged or not at
# the same time. Some layers may only have adapter A, some only adapter B, so it's not as easy as just checking
# which adapters are merged on each layer.
# First, determine all adapters that are merged on at least on module.
merged_all: set[str] = set()
for status in layer_status:
merged_all.update(status.merged_adapters)
# Next, check if on any layer, on of these adapters is not merged.
merged_adapters: list[str] | Literal["irregular"] = sorted(merged_all)
for status in layer_status:
unmerged = set(status.available_adapters) - set(status.merged_adapters)
if unmerged & merged_all:
# there is overlap between unmerged adapters and adapters that should be merged
merged_adapters = "irregular"
break
# check status of requires_grad
# first, merge the values for all layers
requires_grad_all: dict[str, list[bool | Literal["irregular"]]] = collections.defaultdict(list)
for status in layer_status:
for key, val in status.requires_grad.items():
requires_grad_all[key].append(val)
# then, check if the values are consistent
def check_irrgular(vals: list[bool | Literal["irregular"]]) -> bool | Literal["irregular"]:
if all(val is True for val in vals):
return True
if all(val is False for val in vals):
return False
return "irregular"
requires_grad = {key: check_irrgular(vals) for key, vals in requires_grad_all.items()}
adapter_model_status = TunerModelStatus(
base_model_type=base_model_type,
adapter_model_type=adapter_model_type,
peft_types=peft_types,
trainable_params=trainable_params,
total_params=total_params,
num_adapter_layers=num_adapter_layers,
enabled=enabled,
active_adapters=active_adapters,
merged_adapters=merged_adapters,
requires_grad=requires_grad,
available_adapters=available_adapters,
)
return adapter_model_status