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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 math | |
import warnings | |
from typing import Any, Optional, Union | |
import torch | |
import torch.nn as nn | |
import torch.nn.functional as F | |
from accelerate.utils.imports import is_xpu_available | |
from torch import svd_lowrank | |
from transformers.pytorch_utils import Conv1D | |
from peft.tuners.tuners_utils import BaseTunerLayer, check_adapters_to_merge | |
from peft.utils.integrations import dequantize_module_weight, gather_params_ctx, get_bnb_param_type | |
from peft.utils.other import transpose | |
from .config import LoraConfig | |
from .dora import DoraConv2dLayer, DoraConv3dLayer, DoraEmbeddingLayer, DoraLinearLayer, _DoraConvNdLayer | |
class LoraLayer(BaseTunerLayer): | |
# All names of layers that may contain (trainable) adapter weights | |
adapter_layer_names = ("lora_A", "lora_B", "lora_embedding_A", "lora_embedding_B","lora_route") | |
# All names of other parameters that may contain adapter-related parameters | |
other_param_names = ("r", "lora_alpha", "scaling", "lora_dropout") | |
def __init__(self, base_layer: nn.Module, ephemeral_gpu_offload: bool = False, **kwargs) -> None: | |
self.base_layer = base_layer | |
self.r = {} | |
self.lora_alpha = {} | |
self.scaling = {} | |
self.lora_dropout = nn.ModuleDict({}) | |
self.lora_A = nn.ModuleDict({}) | |
self.lora_B = nn.ModuleDict({}) | |
# For Embedding layer | |
self.lora_embedding_A = nn.ParameterDict({}) | |
self.lora_embedding_B = nn.ParameterDict({}) | |
# For Moe Lora | |
self.lora_route = nn.ModuleDict({}) | |
# Mark the weight as unmerged | |
self._disable_adapters = False | |
self.merged_adapters = [] | |
self.use_dora: dict[str, bool] = {} | |
self.lora_bias: dict[str, bool] = {} | |
self.lora_magnitude_vector = torch.nn.ModuleDict() # for DoRA | |
self._caches: dict[str, Any] = {} | |
self.ephemeral_gpu_offload: bool = ephemeral_gpu_offload | |
self.kwargs = kwargs | |
base_layer = self.get_base_layer() | |
if isinstance(base_layer, nn.Linear): | |
in_features, out_features = base_layer.in_features, base_layer.out_features | |
elif isinstance(base_layer, nn.Conv2d): | |
in_features, out_features = base_layer.in_channels, base_layer.out_channels | |
elif isinstance(base_layer, nn.Conv3d): | |
in_features, out_features = base_layer.in_channels, base_layer.out_channels | |
elif isinstance(base_layer, nn.Embedding): | |
in_features, out_features = base_layer.num_embeddings, base_layer.embedding_dim | |
elif isinstance(base_layer, Conv1D): | |
in_features, out_features = ( | |
base_layer.weight.ds_shape if hasattr(base_layer.weight, "ds_shape") else base_layer.weight.shape | |
) | |
elif hasattr(base_layer, "infeatures") and hasattr(base_layer, "outfeatures"): | |
# QuantLinear | |
in_features, out_features = base_layer.infeatures, base_layer.outfeatures | |
elif hasattr(base_layer, "input_size") and hasattr(base_layer, "output_size"): | |
# Megatron ColumnParallelLinear,RowParallelLinear | |
in_features, out_features = base_layer.input_size, base_layer.output_size | |
elif hasattr(base_layer, "codebooks") and base_layer.__class__.__name__ == "QuantizedLinear": | |
# AQLM QuantLinear | |
in_features, out_features = base_layer.in_features, base_layer.out_features | |
elif hasattr(base_layer, "w_bit") and base_layer.__class__.__name__ == "WQLinear_GEMM": | |
# Awq layers | |
in_features, out_features = base_layer.in_features, base_layer.out_features | |
elif base_layer.__class__.__name__ == "EetqLinear": | |
# Eetq layers | |
in_features, out_features = base_layer.in_features, base_layer.out_features | |
elif hasattr(base_layer, "W_q") and base_layer.__class__.__name__ == "HQQLinear": | |
# HQQ layers | |
in_features, out_features = base_layer.in_features, base_layer.out_features | |
else: | |
# possibly support user provided custom layer types using dynamic dispatch | |
if hasattr(base_layer, "in_features") and hasattr(base_layer, "out_features"): | |
in_features, out_features = base_layer.in_features, base_layer.out_features | |
else: | |
in_features, out_features = None, None | |
warnings.warn( | |
f"Unsupported layer type '{type(base_layer)}' encountered, proceed at your own risk.", UserWarning | |
) | |
self.in_features = in_features | |
self.out_features = out_features | |
def update_layer( | |
self, | |
adapter_name, | |
r, | |
lora_alpha, | |
lora_dropout, | |
init_lora_weights, | |
use_rslora, | |
use_dora: bool = False, | |
lora_bias: bool = False, | |
): | |
# This code works for linear layers, override for other layer types | |
if r <= 0: | |
raise ValueError(f"`r` should be a positive integer value but the value passed is {r}") | |
self.r[adapter_name] = r | |
self.lora_alpha[adapter_name] = lora_alpha | |
if lora_dropout > 0.0: | |
lora_dropout_layer = nn.Dropout(p=lora_dropout) | |
else: | |
lora_dropout_layer = nn.Identity() | |
self.lora_dropout.update(nn.ModuleDict({adapter_name: lora_dropout_layer})) | |
# Actual trainable parameters | |
self.lora_A[adapter_name] = nn.Linear(self.in_features, r, bias=False) | |
self.lora_B[adapter_name] = nn.Linear(r, self.out_features, bias=lora_bias) | |
self.lora_bias[adapter_name] = lora_bias | |
if use_rslora: | |
self.scaling[adapter_name] = lora_alpha / math.sqrt(r) | |
else: | |
self.scaling[adapter_name] = lora_alpha / r | |
# for inits that require access to the base weight, use gather_param_ctx so that the weight is gathered when using DeepSpeed | |
if isinstance(init_lora_weights, str) and init_lora_weights.startswith("pissa"): | |
with gather_params_ctx(self.get_base_layer().weight): | |
self.pissa_init(adapter_name, init_lora_weights) | |
elif isinstance(init_lora_weights, str) and init_lora_weights.lower() == "olora": | |
with gather_params_ctx(self.get_base_layer().weight): | |
self.olora_init(adapter_name) | |
elif init_lora_weights == "loftq": | |
with gather_params_ctx(self.get_base_layer().weight): | |
self.loftq_init(adapter_name) | |
elif init_lora_weights == "eva": | |
nn.init.zeros_(self.lora_B[adapter_name].weight) | |
elif init_lora_weights: | |
self.reset_lora_parameters(adapter_name, init_lora_weights) | |
# call this before dora_init | |
self._move_adapter_to_device_of_base_layer(adapter_name) | |
if use_dora: | |
self.dora_init(adapter_name) | |
self.use_dora[adapter_name] = True | |
else: | |
self.use_dora[adapter_name] = False | |
self.set_adapter(self.active_adapters) | |
def reset_lora_parameters(self, adapter_name, init_lora_weights): | |
if init_lora_weights is False: | |
return | |
if adapter_name in self.lora_A.keys(): | |
if init_lora_weights is True: | |
# initialize A the same way as the default for nn.Linear and B to zero | |
# https://github.com/microsoft/LoRA/blob/a0a92e0f26c067cf94747bdbf1ce73793fa44d19/loralib/layers.py#L124 | |
nn.init.kaiming_uniform_(self.lora_A[adapter_name].weight, a=math.sqrt(5)) | |
elif init_lora_weights.lower() == "gaussian": | |
nn.init.normal_(self.lora_A[adapter_name].weight, std=1 / self.r[adapter_name]) | |
else: | |
raise ValueError(f"Unknown initialization {init_lora_weights=}") | |
nn.init.zeros_(self.lora_B[adapter_name].weight) | |
if self.lora_bias[adapter_name]: | |
nn.init.zeros_(self.lora_B[adapter_name].bias) | |
if adapter_name in self.lora_embedding_A.keys(): | |
# Initialize A to zeros and B the same way as the default for nn.Embedding, see: | |
# https://github.com/microsoft/LoRA/blob/4c0333854cb905966f8cc4e9a74068c1e507c7b7/loralib/layers.py#L59-L60 | |
nn.init.zeros_(self.lora_embedding_A[adapter_name]) | |
nn.init.normal_(self.lora_embedding_B[adapter_name]) | |
if self.lora_bias[adapter_name]: | |
# embeddings are not supported at the moment, but still adding this for consistency | |
nn.init.zeros_(self.lora_embedding_B[adapter_name].bias) | |
def olora_init(self, adapter_name): | |
base_layer = self.get_base_layer() | |
orig_weight = base_layer.weight | |
bnb_param_type = get_bnb_param_type(orig_weight) | |
dtype = orig_weight.dtype | |
if bnb_param_type: | |
# check without importing bitsandbytes and robust to bnb_4bit_quant_storage=float* | |
weight_tensor = dequantize_module_weight(base_layer) | |
elif dtype in [torch.float32, torch.float16, torch.bfloat16]: | |
weight_tensor = orig_weight | |
else: | |
raise TypeError(f"Unsupported data type for the base layer. Got {dtype}.") | |
scale_factor = self.scaling[adapter_name] | |
r = self.r[adapter_name] | |
weight_tensor = weight_tensor.to(torch.float32) | |
Q, R = torch.linalg.qr(weight_tensor.data) | |
Qr, Rr = Q[:, :r], R[:r] | |
self.lora_A[adapter_name].weight.data = Rr.contiguous() | |
self.lora_B[adapter_name].weight.data = Qr.contiguous() | |
weight_tensor.data -= scale_factor * self.lora_B[adapter_name].weight @ self.lora_A[adapter_name].weight | |
if bnb_param_type == "4bit": | |
weight_tensor = orig_weight.__class__( | |
weight_tensor, | |
quant_type=orig_weight.quant_type, | |
quant_storage=orig_weight.quant_storage, | |
compress_statistics=orig_weight.compress_statistics, | |
module=orig_weight.module, | |
).to(orig_weight.device) | |
base_layer.weight = weight_tensor | |
elif bnb_param_type == "8bit": | |
weight_tensor = orig_weight.__class__( | |
weight_tensor, | |
requires_grad=orig_weight.requires_grad, | |
has_fp16_weights=orig_weight.has_fp16_weights, | |
).to(orig_weight.device) | |
base_layer.weight = weight_tensor | |
else: | |
weight_tensor = weight_tensor.to(dtype) | |
base_layer.weight.data = weight_tensor | |
def pissa_init(self, adapter_name, init_lora_weights): | |
weight = self.get_base_layer().weight | |
dtype = weight.dtype | |
if dtype not in [torch.float32, torch.float16, torch.bfloat16]: | |
raise TypeError( | |
"Please initialize PiSSA under float32, float16, or bfloat16. " | |
"Subsequently, re-quantize the residual model to help minimize quantization errors." | |
) | |
weight = transpose(weight.to(torch.float32), self.fan_in_fan_out) | |
if init_lora_weights == "pissa": | |
# USV^T = W <-> VSU^T = W^T, where W^T = weight.data in R^{out_channel, in_channel}, | |
V, S, Uh = torch.linalg.svd(weight.data, full_matrices=False) | |
Vr = V[:, : self.r[adapter_name]] | |
Sr = S[: self.r[adapter_name]] | |
Sr /= self.scaling[adapter_name] | |
Uhr = Uh[: self.r[adapter_name]] | |
elif len(init_lora_weights.split("_niter_")) == 2: | |
Vr, Sr, Ur = svd_lowrank( | |
weight.data, self.r[adapter_name], niter=int(init_lora_weights.split("_niter_")[-1]) | |
) | |
Sr /= self.scaling[adapter_name] | |
Uhr = Ur.t() | |
else: | |
raise ValueError( | |
f"init_lora_weights should be 'pissa' or 'pissa_niter_[number of iters]', got {init_lora_weights} instead." | |
) | |
lora_A = torch.diag(torch.sqrt(Sr)) @ Uhr | |
lora_B = Vr @ torch.diag(torch.sqrt(Sr)) | |
self.lora_A[adapter_name].weight.data = lora_A | |
self.lora_B[adapter_name].weight.data = lora_B | |
weight = weight.data - self.scaling[adapter_name] * lora_B @ lora_A | |
weight = transpose(weight.to(dtype), self.fan_in_fan_out) | |
self.get_base_layer().weight.data = weight | |
def loftq_init(self, adapter_name): | |
from peft.utils.loftq_utils import loftq_init | |
weight = self.get_base_layer().weight | |
kwargs = { | |
"num_bits": self.kwargs.get("loftq_bits", 4), | |
"reduced_rank": self.r[adapter_name], | |
"num_iter": self.kwargs.get("loftq_iter", 1), | |
} | |
qweight, lora_A, lora_B = loftq_init(weight, **kwargs) | |
if adapter_name in self.lora_A.keys(): | |
# initialize A the same way as the default for nn.Linear and B to zero | |
self.lora_A[adapter_name].weight.data = lora_A | |
self.lora_B[adapter_name].weight.data = lora_B | |
if adapter_name in self.lora_embedding_A.keys(): | |
# initialize a the same way as the default for nn.linear and b to zero | |
self.lora_embedding_A[adapter_name].weight.data = lora_A | |
self.lora_embedding_B[adapter_name].weight.data = lora_B | |
self.get_base_layer().weight.data = qweight | |
def dora_init(self, adapter_name: str) -> None: | |
if not self.lora_magnitude_vector: | |
# first dora layer being added, add lora_magnitude_vector to the list of learnable parameters | |
self.adapter_layer_names = self.adapter_layer_names[:] + ("lora_magnitude_vector",) | |
dora_layer = DoraLinearLayer(fan_in_fan_out=getattr(self, "fan_in_fan_out", False)) | |
lora_A = self.lora_A[adapter_name].weight | |
lora_B = self.lora_B[adapter_name].weight | |
place_on_cpu = self.ephemeral_gpu_offload and (lora_A.device.type == "cpu" or lora_B.device.type == "cpu") | |
if self.ephemeral_gpu_offload: | |
if lora_A.device.type in ["cuda", "xpu"]: | |
lora_B = lora_B.to(lora_A.device) | |
else: | |
if lora_B.device.type not in ["cuda", "xpu"]: | |
if is_xpu_available(): | |
lora_B = lora_B.to("xpu") | |
else: | |
lora_B = lora_B.to("cuda") | |
lora_A = lora_A.to(lora_B.device) | |
scaling = self.scaling[adapter_name] | |
dora_layer.update_layer( | |
base_layer=self.get_base_layer(), lora_A=lora_A, lora_B=lora_B, scaling=scaling, place_on_cpu=place_on_cpu | |
) | |
self.lora_magnitude_vector[adapter_name] = dora_layer | |
def _cache_store(self, key: str, value: Any) -> None: | |
self._caches[key] = value | |
def _cache_pop(self, key: str) -> Any: | |
value = self._caches.pop(key) | |
return value | |
def set_scale(self, adapter, scale): | |
if adapter not in self.scaling: | |
# Ignore the case where the adapter is not in the layer | |
return | |
self.scaling[adapter] = scale * self.lora_alpha[adapter] / self.r[adapter] | |
def scale_layer(self, scale: float) -> None: | |
if scale == 1: | |
return | |
for active_adapter in self.active_adapters: | |
if active_adapter not in self.lora_A.keys(): | |
continue | |
self.scaling[active_adapter] *= scale | |
def unscale_layer(self, scale=None) -> None: | |
for active_adapter in self.active_adapters: | |
if active_adapter not in self.lora_A.keys(): | |
continue | |
if scale is None: | |
self.scaling[active_adapter] = self.lora_alpha[active_adapter] / self.r[active_adapter] | |
else: | |
self.scaling[active_adapter] /= scale | |
def _check_forward_args(self, x, *args, **kwargs): | |
"""Check if the arguments are compatible with the configs and state of the model""" | |
adapter_names = kwargs.get("adapter_names", None) | |
if adapter_names is None: | |
return | |
if len(x) != len(adapter_names): | |
msg = ( | |
"Length of `adapter_names` should be the same as the number of inputs, but got " | |
f"{len(adapter_names)} and {len(x)} respectively." | |
) | |
raise ValueError(msg) | |
if self.merged: | |
# It is unclear what would be the right thing to do if users pass adapter_names and there are merged | |
# adapters. Therefore, it is better to raise an error in this case. | |
msg = "Cannot pass `adapter_names` when there are merged adapters, please call `unmerge_adapter` first." | |
raise ValueError(msg) | |
# DoRA is not supported (yet), check that it's not being used. Don't check "__base__", as this is the | |
# placeholder for the base model. | |
unique_adapters = {name for name in adapter_names if name != "__base__"} | |
for adapter_name in unique_adapters: | |
if self.use_dora.get(adapter_name, False): | |
msg = "Cannot pass `adapter_names` when DoRA is enabled." | |
raise ValueError(msg) | |
def _mixed_batch_forward( | |
self, x: torch.Tensor, *args: Any, adapter_names: list[str], **kwargs: Any | |
) -> torch.Tensor: | |
# This is a special method that handles the case when users pass the argument `adapter_names`. This is an | |
# extra argument that allows mixing different adapters in the same batch at inference time. | |
result = self.base_layer(x, *args, **kwargs) | |
torch_result_dtype = result.dtype | |
unique_adapters = set(adapter_names) | |
sub_batch_indices_list = [] | |
for adapter in unique_adapters: | |
sub_batch_indices_list.append([index for index, item in enumerate(adapter_names) if item == adapter]) | |
for i, active_adapter in enumerate(unique_adapters): | |
if active_adapter == "__base__": | |
continue | |
if active_adapter not in self.lora_A.keys(): | |
continue | |
lora_A = self.lora_A[active_adapter] | |
lora_B = self.lora_B[active_adapter] | |
dropout = self.lora_dropout[active_adapter] | |
scaling = self.scaling[active_adapter] | |
# getting the sub-batch, passing it to LoRA layers and updating the corresponding indices of the linear | |
# layer output | |
sub_batch = x[sub_batch_indices_list[i]].to(lora_A.weight.dtype) | |
lora_output = lora_B(lora_A(dropout(sub_batch))) * scaling | |
result[sub_batch_indices_list[i]] += lora_output.to(torch_result_dtype) | |
return result | |
# Below code is based on https://github.com/microsoft/LoRA/blob/main/loralib/layers.py | |
# and modified to work with PyTorch FSDP | |
# ------------------------------------------------------------------------------------------ | |
# Copyright (c) Microsoft Corporation. All rights reserved. | |
# Licensed under the MIT License (MIT). See LICENSE in the repo root for license information. | |
# ------------------------------------------------------------------------------------------ | |
class Linear(nn.Module, LoraLayer): | |
# Lora implemented in a dense layer | |
def __init__( | |
self, | |
base_layer, | |
adapter_name: str, | |
r: int = 0, | |
lora_alpha: int = 1, | |
lora_dropout: float = 0.0, | |
fan_in_fan_out: bool = False, # Set this to True if the layer to replace stores weight like (fan_in, fan_out) | |
is_target_conv_1d_layer: bool = False, | |
init_lora_weights: Union[bool, str] = True, | |
use_rslora: bool = False, | |
use_dora: bool = False, | |
lora_bias: bool = False, | |
**kwargs, | |
) -> None: | |
super().__init__() | |
LoraLayer.__init__(self, base_layer, **kwargs) | |
self.fan_in_fan_out = fan_in_fan_out | |
self._active_adapter = adapter_name | |
self.num_experts = kwargs.get("num_experts", 1) | |
self.expert_rank = kwargs.get("expert_rank", 4) | |
self.expert_alpha = kwargs.get("expert_alpha", 4) | |
self.top_k = kwargs.get("top_k", 4) | |
self.blc_alpha = kwargs.get("blc_alpha", 0.0) | |
self.blc_weight = kwargs.get("blc_weight", 0.0) | |
if "ff.net" in kwargs["current_key"] or "proj_out" in kwargs["current_key"]: | |
self.moe_lora = True | |
self.update_moe_layer( | |
adapter_name, | |
r, | |
lora_alpha=lora_alpha, | |
lora_dropout=lora_dropout, | |
init_lora_weights=init_lora_weights, | |
use_rslora=use_rslora, | |
use_dora=use_dora, | |
lora_bias=lora_bias, | |
num_experts=self.num_experts, | |
expert_rank=self.expert_rank, | |
expert_alpha=self.expert_alpha, | |
) | |
else: | |
self.moe_lora = False | |
self.update_layer( | |
adapter_name, | |
r, | |
lora_alpha=lora_alpha, | |
lora_dropout=lora_dropout, | |
init_lora_weights=init_lora_weights, | |
use_rslora=use_rslora, | |
use_dora=use_dora, | |
lora_bias=lora_bias, | |
) | |
self.is_target_conv_1d_layer = is_target_conv_1d_layer | |
def update_moe_layer( | |
self, | |
adapter_name, | |
r, | |
lora_alpha, | |
lora_dropout, | |
init_lora_weights, | |
use_rslora, | |
use_dora: bool = False, | |
lora_bias: bool = False, | |
num_experts: int = 1, | |
expert_rank: int = 4, | |
expert_alpha: float = 4, | |
): | |
expert_list = [] | |
for i in range(num_experts): | |
expert_list.append(f"expert_{i}") | |
# This code works for linear layers, override for other layer types | |
if r <= 0 or num_experts <= 0 or expert_rank <= 0: | |
raise ValueError(f"`r` should be a positive integer value but the value passed is {r}") | |
if self.top_k > num_experts: | |
raise ValueError(f"`top_k` should be a positive integer value but the value passed is {self.top_k}") | |
self.r[adapter_name] = expert_rank | |
self.lora_alpha[adapter_name] = expert_alpha | |
if lora_dropout > 0.0: | |
lora_dropout_layer = nn.Dropout(p=lora_dropout) | |
else: | |
lora_dropout_layer = nn.Identity() | |
self.lora_dropout.update(nn.ModuleDict({adapter_name: lora_dropout_layer})) | |
# Actual trainable parameters | |
# experts in dict | |
for i in range(num_experts): | |
expert_name = expert_list[i] | |
self.lora_A[expert_name] = nn.Linear(self.in_features, expert_rank, bias=False) | |
self.lora_B[expert_name] = nn.Linear(expert_rank, self.out_features, bias=lora_bias) | |
self.r[expert_name] = expert_rank | |
self.lora_alpha[expert_name] = expert_alpha | |
self.lora_bias[expert_name] = lora_bias | |
self.lora_dropout.update(nn.ModuleDict({expert_name: lora_dropout_layer})) | |
self.scaling[expert_name] = expert_alpha / expert_rank | |
self.lora_route[adapter_name] = nn.Linear(self.in_features, num_experts, bias=False) | |
self.lora_bias[adapter_name] = lora_bias | |
if use_rslora: | |
self.scaling[adapter_name] = expert_alpha / math.sqrt(expert_rank) | |
else: | |
self.scaling[adapter_name] = expert_alpha / expert_rank | |
# for inits that require access to the base weight, use gather_param_ctx so that the weight is gathered when using DeepSpeed | |
if isinstance(init_lora_weights, str) and init_lora_weights.startswith("pissa"): | |
with gather_params_ctx(self.get_base_layer().weight): | |
self.pissa_init(adapter_name, init_lora_weights) | |
elif isinstance(init_lora_weights, str) and init_lora_weights.lower() == "olora": | |
with gather_params_ctx(self.get_base_layer().weight): | |
self.olora_init(adapter_name) | |
elif init_lora_weights == "loftq": | |
with gather_params_ctx(self.get_base_layer().weight): | |
self.loftq_init(adapter_name) | |
elif init_lora_weights == "eva": | |
nn.init.zeros_(self.lora_B[adapter_name].weight) | |
elif init_lora_weights: | |
self.reset_lora_parameters(adapter_name, init_lora_weights) | |
for i in range(num_experts): | |
expert_name = f"expert_{i}" | |
self.reset_lora_parameters(expert_name, init_lora_weights) | |
# call this before dora_init | |
self._move_adapter_to_device_of_base_layer(adapter_name) | |
for i in range(num_experts): | |
expert_name = expert_list[i] | |
self._move_adapter_to_device_of_base_layer(expert_name) | |
if use_dora: | |
self.dora_init(adapter_name) | |
self.use_dora[adapter_name] = True | |
else: | |
self.use_dora[adapter_name] = False | |
self.set_adapter(self.active_adapters+expert_list) | |
def merge(self, safe_merge: bool = False, adapter_names: Optional[list[str]] = None) -> None: | |
""" | |
Merge the active adapter weights into the base weights | |
Args: | |
safe_merge (`bool`, *optional*): | |
If True, the merge operation will be performed in a copy of the original weights and check for NaNs | |
before merging the weights. This is useful if you want to check if the merge operation will produce | |
NaNs. Defaults to `False`. | |
adapter_names (`list[str]`, *optional*): | |
The list of adapter names that should be merged. If None, all active adapters will be merged. Defaults | |
to `None`. | |
""" | |
adapter_names = check_adapters_to_merge(self, adapter_names) | |
if not adapter_names: | |
# no adapter to merge | |
return | |
for active_adapter in adapter_names: | |
if active_adapter in self.lora_A.keys(): | |
base_layer = self.get_base_layer() | |
if safe_merge: | |
# Note that safe_merge will be slower than the normal merge | |
# because of the copy operation. | |
orig_weights = base_layer.weight.data.clone() | |
delta_weight = self.get_delta_weight(active_adapter) | |
if not self.use_dora[active_adapter]: | |
orig_weights += delta_weight | |
else: | |
# handle dora | |
# since delta_weight already includes scaling, set it to 1 here | |
weight_norm = ( | |
self.lora_magnitude_vector[active_adapter] | |
.get_weight_norm(orig_weights, transpose(delta_weight, self.fan_in_fan_out), scaling=1) | |
.detach() | |
) | |
# We need to cache weight_norm because it has to be based on the original weights. We | |
# cannot calculate it on the fly based on the merged weights when unmerging because its a | |
# different value | |
self._cache_store(f"{active_adapter}-weight_norm", weight_norm) | |
dora_factor = self.lora_magnitude_vector[active_adapter].weight / weight_norm | |
dora_factor = transpose(dora_factor.view(-1, 1), self.fan_in_fan_out) | |
orig_weights = dora_factor * (orig_weights + delta_weight) | |
if not torch.isfinite(orig_weights).all(): | |
raise ValueError( | |
f"NaNs detected in the merged weights. The adapter {active_adapter} seems to be broken" | |
) | |
base_layer.weight.data = orig_weights | |
if self.lora_bias[active_adapter]: | |
new_bias = base_layer.bias + self.lora_B[active_adapter].bias | |
if not torch.isfinite(new_bias).all(): | |
raise ValueError( | |
f"NaNs detected in the merged weights. The adapter {active_adapter} seems to be broken" | |
) | |
base_layer.bias.data = new_bias | |
else: | |
delta_weight = self.get_delta_weight(active_adapter) | |
if not self.use_dora[active_adapter]: | |
base_layer.weight.data += delta_weight | |
else: | |
# handle dora | |
# since delta_weight already includes scaling, set it to 1 here | |
weight_norm = ( | |
self.lora_magnitude_vector[active_adapter] | |
.get_weight_norm( | |
base_layer.weight, transpose(delta_weight, self.fan_in_fan_out), scaling=1 | |
) | |
.detach() | |
) | |
# We need to cache weight_norm because it has to be based on the original weights. We | |
# cannot calculate it on the fly based on the merged weights when unmerging because its a | |
# different value | |
self._cache_store(f"{active_adapter}-weight_norm", weight_norm) | |
dora_factor = self.lora_magnitude_vector[active_adapter].weight / weight_norm | |
new_weight = dora_factor.view(-1, 1) * (base_layer.weight.data + delta_weight) | |
base_layer.weight.data = new_weight | |
if self.lora_bias[active_adapter]: | |
base_layer.bias.data += self.lora_B[active_adapter].bias | |
self.merged_adapters.append(active_adapter) | |
def unmerge(self) -> None: | |
""" | |
This method unmerges all merged adapter layers from the base weights. | |
""" | |
if not self.merged: | |
warnings.warn("Already unmerged. Nothing to do.") | |
return | |
while len(self.merged_adapters) > 0: | |
active_adapter = self.merged_adapters.pop() | |
if active_adapter in self.lora_A.keys(): | |
weight = self.get_base_layer().weight | |
delta_weight = self.get_delta_weight(active_adapter) | |
if not self.use_dora[active_adapter]: | |
weight.data -= delta_weight | |
else: | |
weight_norm = self._cache_pop(f"{active_adapter}-weight_norm") | |
dora_factor = self.lora_magnitude_vector[active_adapter].weight / weight_norm | |
weight_orig = weight.data / dora_factor.view(-1, 1) - delta_weight | |
weight.data = weight_orig | |
if self.lora_bias[active_adapter]: | |
self.get_base_layer().bias.data -= self.lora_B[active_adapter].bias | |
def get_delta_weight(self, adapter) -> torch.Tensor: | |
""" | |
Compute the delta weight for the given adapter. | |
Args: | |
adapter (str): | |
The name of the adapter for which the delta weight should be computed. | |
""" | |
device = self.lora_B[adapter].weight.device | |
dtype = self.lora_A[adapter].weight.dtype | |
# In case users wants to merge the adapter weights that are in | |
# (b)float16 while being on CPU, we need to cast the weights to float32, perform the merge and then cast back to | |
# (b)float16 because some CPUs have slow bf16/fp16 matmuls. | |
cast_to_fp32 = device.type == "cpu" and (dtype == torch.float16 or dtype == torch.bfloat16) | |
weight_A = self.lora_A[adapter].weight | |
weight_B = self.lora_B[adapter].weight | |
if cast_to_fp32: | |
weight_A = weight_A.float() | |
weight_B = weight_B.float() | |
output_tensor = transpose(weight_B @ weight_A, self.fan_in_fan_out) * self.scaling[adapter] | |
if cast_to_fp32: | |
output_tensor = output_tensor.to(dtype=dtype) | |
# cast back the weights | |
self.lora_A[adapter].weight.data = weight_A.to(dtype) | |
self.lora_B[adapter].weight.data = weight_B.to(dtype) | |
return output_tensor | |
def forward(self, x: torch.Tensor, *args: Any, **kwargs: Any) -> torch.Tensor: | |
if self.moe_lora: | |
return self.moe_forward(x, *args, **kwargs) | |
self._check_forward_args(x, *args, **kwargs) | |
adapter_names = kwargs.pop("adapter_names", None) | |
if self.disable_adapters: | |
if self.merged: | |
self.unmerge() | |
result = self.base_layer(x, *args, **kwargs) | |
elif adapter_names is not None: | |
result = self._mixed_batch_forward(x, *args, adapter_names=adapter_names, **kwargs) | |
elif self.merged: | |
result = self.base_layer(x, *args, **kwargs) | |
else: | |
result = self.base_layer(x, *args, **kwargs) | |
torch_result_dtype = result.dtype | |
for active_adapter in self.active_adapters: | |
if active_adapter not in self.lora_A.keys(): | |
continue | |
lora_A = self.lora_A[active_adapter] | |
lora_B = self.lora_B[active_adapter] | |
dropout = self.lora_dropout[active_adapter] | |
scaling = self.scaling[active_adapter] | |
x = x.to(lora_A.weight.dtype) | |
if not self.use_dora[active_adapter]: | |
result = result + lora_B(lora_A(dropout(x))) * scaling | |
else: | |
if isinstance(dropout, nn.Identity) or not self.training: | |
base_result = result | |
else: | |
x = dropout(x) | |
base_result = None | |
result = result + self.lora_magnitude_vector[active_adapter]( | |
x, | |
lora_A=lora_A, | |
lora_B=lora_B, | |
scaling=scaling, | |
base_layer=self.get_base_layer(), | |
base_result=base_result, | |
) | |
result = result.to(torch_result_dtype) | |
return result | |
def moe_forward(self, x: torch.Tensor, *args: Any, **kwargs: Any) -> torch.Tensor: | |
moe_type="token_wise" | |
self._check_forward_args(x, *args, **kwargs) | |
adapter_names = kwargs.pop("adapter_names", None) | |
if self.disable_adapters: | |
if self.merged: | |
self.unmerge() | |
result = self.base_layer(x, *args, **kwargs) | |
elif adapter_names is not None: | |
result = self._mixed_batch_forward(x, *args, adapter_names=adapter_names, **kwargs) | |
elif self.merged: | |
result = self.base_layer(x, *args, **kwargs) | |
else: | |
if moe_type == "token_wise": | |
result = self.base_layer(x, *args, **kwargs) | |
torch_result_dtype = result.dtype | |
activate_adapter_name = self.active_adapters[0] | |
# 计算路由分数 | |
route_logits = self.lora_route[activate_adapter_name](x) | |
# 获取 top-k,保持梯度流 | |
top_k_probs, top_k_indices = torch.topk(route_logits, k=self.top_k, dim=-1) | |
top_k_probs = F.softmax(top_k_probs, dim=-1, dtype=torch.float32).to(result.dtype) | |
# 创建掩码并应用 | |
route_weight = torch.zeros_like(route_logits) | |
route_weight=route_weight.scatter_(-1, top_k_indices, top_k_probs) | |
# 计算 softmax,topk之外的weight应该是0 | |
#print(route_weight.shape) | |
#print(route_weight) | |
# 应用专家 | |
for i in range(self.num_experts): | |
expert_name = f"expert_{i}" | |
lora_A = self.lora_A[expert_name] | |
lora_B = self.lora_B[expert_name] | |
scaling = self.scaling[expert_name] | |
dropout = self.lora_dropout[expert_name] | |
result += lora_B(lora_A(dropout(x))) * scaling * torch.unsqueeze(route_weight[:,:,i], -1) | |
result = result.to(torch_result_dtype) | |
elif moe_type == "sequence_wise": | |
result = self.base_layer(x, *args, **kwargs) | |
torch_result_dtype = result.dtype | |
activate_adapter_name = self.active_adapters[0] | |
route_logits = self.lora_route[activate_adapter_name](x[:,0]) | |
# 将route_logits扩展到与x相同的形状 | |
route_logits=route_logits.unsqueeze(1).repeat(1,x.shape[1],1) | |
# 获取 top-k,保持梯度流 | |
top_k_probs, top_k_indices = torch.topk(route_logits, k=self.top_k, dim=-1) | |
top_k_probs = F.softmax(top_k_probs, dim=-1, dtype=torch.float32).to(result.dtype) | |
# 创建掩码并应用,mask应该初始值是负无穷-inf | |
route_weight = torch.zeros_like(route_logits) | |
route_weight=route_weight.scatter_(-1, top_k_indices, top_k_probs) | |
# 计算 softmax,topk之外的weight应该是0 | |
# 应用专家 | |
for i in range(self.num_experts): | |
expert_name = f"expert_{i}" | |
lora_A = self.lora_A[expert_name] | |
lora_B = self.lora_B[expert_name] | |
scaling = self.scaling[expert_name] | |
dropout = self.lora_dropout[expert_name] | |
result += lora_B(lora_A(dropout(x))) * scaling * torch.unsqueeze(route_weight[:,:,i], -1) | |
result = result.to(torch_result_dtype) | |
return result | |
def __repr__(self) -> str: | |
rep = super().__repr__() | |
return "lora." + rep | |
class Embedding(nn.Module, LoraLayer): | |
# LoRA implemented in a Embedding layer | |
def __init__( | |
self, | |
base_layer: nn.Module, | |
adapter_name: str, | |
r: int = 0, | |
lora_alpha: int = 1, | |
lora_dropout: float = 0.0, | |
init_lora_weights: Union[bool, str] = True, | |
use_rslora: bool = False, | |
use_dora: bool = False, | |
lora_bias: bool = False, | |
**kwargs, | |
) -> None: | |
if lora_bias: | |
# lora_bias=True is not supported (yet) for embedding layers, as they use nn.Parameter | |
raise ValueError(f"lora_bias={lora_bias} is not supported for {self.__class__.__name__}.") | |
super().__init__() | |
LoraLayer.__init__(self, base_layer) | |
self._active_adapter = adapter_name | |
self.update_layer( | |
adapter_name, | |
r, | |
lora_alpha=lora_alpha, | |
lora_dropout=lora_dropout, | |
init_lora_weights=init_lora_weights, | |
use_rslora=use_rslora, | |
use_dora=use_dora, | |
lora_bias=lora_bias, | |
) | |
def update_layer( | |
self, adapter_name, r, lora_alpha, lora_dropout, init_lora_weights, use_rslora, use_dora, lora_bias | |
): | |
if r <= 0: | |
raise ValueError(f"`r` should be a positive integer value but the value passed is {r}") | |
self.r[adapter_name] = r | |
self.lora_alpha[adapter_name] = lora_alpha | |
if lora_dropout > 0.0: | |
lora_dropout_layer = nn.Dropout(p=lora_dropout) | |
else: | |
lora_dropout_layer = nn.Identity() | |
self.lora_dropout[adapter_name] = lora_dropout_layer | |
# Actual trainable parameters | |
weight_A = torch.randn((r, self.in_features)) | |
weight_B = torch.randn((self.out_features, r)) | |
self.lora_embedding_A[adapter_name] = nn.Parameter(weight_A) | |
self.lora_embedding_B[adapter_name] = nn.Parameter(weight_B) | |
self.lora_bias[adapter_name] = lora_bias | |
if use_rslora: | |
self.scaling[adapter_name] = lora_alpha / math.sqrt(r) | |
else: | |
self.scaling[adapter_name] = lora_alpha / r | |
if init_lora_weights == "loftq": | |
self.loftq_init(adapter_name) | |
elif init_lora_weights: | |
self.reset_lora_parameters(adapter_name, init_lora_weights) | |
# call this before dora_init | |
self._move_adapter_to_device_of_base_layer(adapter_name) | |
if use_dora: | |
self.dora_init(adapter_name) | |
self.use_dora[adapter_name] = True | |
else: | |
self.use_dora[adapter_name] = False | |
self.set_adapter(self.active_adapters) | |
def dora_init(self, adapter_name: str) -> None: | |
if self.lora_magnitude_vector is None: | |
# first dora layer being added, add lora_magnitude_vector to the list of learnable parameters | |
self.adapter_layer_names = self.adapter_layer_names[:] + ("lora_magnitude_vector",) | |
dora_layer = DoraEmbeddingLayer(fan_in_fan_out=True) | |
lora_embedding_A = self.lora_embedding_A[adapter_name] | |
lora_embedding_B = self.lora_embedding_B[adapter_name] | |
scaling = self.scaling[adapter_name] | |
dora_layer.update_layer( | |
base_layer=self.get_base_layer(), lora_A=lora_embedding_A, lora_B=lora_embedding_B, scaling=scaling | |
) | |
self.lora_magnitude_vector[adapter_name] = dora_layer | |
def merge(self, safe_merge: bool = False, adapter_names: Optional[list[str]] = None) -> None: | |
""" | |
Merge the active adapter weights into the base weights | |
Args: | |
safe_merge (`bool`, *optional*): | |
If True, the merge operation will be performed in a copy of the original weights and check for NaNs | |
before merging the weights. This is useful if you want to check if the merge operation will produce | |
NaNs. Defaults to `False`. | |
adapter_names (`list[str]`, *optional*): | |
The list of adapter names that should be merged. If None, all active adapters will be merged. Defaults | |
to `None`. | |
""" | |
adapter_names = check_adapters_to_merge(self, adapter_names) | |
if not adapter_names: | |
# no adapter to merge | |
return | |
for active_adapter in adapter_names: | |
if active_adapter in self.lora_embedding_A.keys(): | |
base_layer = self.get_base_layer() | |
if safe_merge: | |
# Note that safe_merge will be slower than the normal merge | |
# because of the copy operation. | |
orig_weights = base_layer.weight.data.clone() | |
orig_weights += self.get_delta_weight(active_adapter) | |
if not torch.isfinite(orig_weights).all(): | |
raise ValueError( | |
f"NaNs detected in the merged weights. The adapter {active_adapter} seems to be broken" | |
) | |
base_layer.weight.data = orig_weights | |
else: | |
base_layer.weight.data += self.get_delta_weight(active_adapter) | |
self.merged_adapters.append(active_adapter) | |
def unmerge(self) -> None: | |
""" | |
This method unmerges all merged adapter layers from the base weights. | |
""" | |
if not self.merged: | |
warnings.warn("Already unmerged. Nothing to do.") | |
return | |
while len(self.merged_adapters) > 0: | |
active_adapter = self.merged_adapters.pop() | |
if active_adapter in self.lora_embedding_A.keys(): | |
self.get_base_layer().weight.data -= self.get_delta_weight(active_adapter) | |
def get_delta_weight(self, adapter) -> torch.Tensor: | |
""" | |
Compute the delta weight for the given adapter. | |
Args: | |
adapter (str): | |
The name of the adapter for which the delta weight should be computed. | |
""" | |
device = self.lora_embedding_B[adapter].device | |
dtype = self.lora_embedding_A[adapter].dtype | |
# In case users wants to merge the adapter weights that are in | |
# (b)float16 while being on CPU, we need to cast the weights to float32, perform the merge and then cast back to | |
# (b)float16 because some CPUs have slow bf16/fp16 matmuls. | |
cast_to_fp32 = device.type == "cpu" and (dtype == torch.float16 or dtype == torch.bfloat16) | |
weight_A = self.lora_embedding_A[adapter] | |
weight_B = self.lora_embedding_B[adapter] | |
if cast_to_fp32: | |
weight_A = weight_A.float() | |
weight_B = weight_B.float() | |
output_tensor = transpose(weight_B @ weight_A, True) * self.scaling[adapter] | |
if cast_to_fp32: | |
output_tensor = output_tensor.to(dtype=dtype) | |
# cast back the weights | |
self.lora_embedding_A[adapter] = weight_A.to(dtype) | |
self.lora_embedding_B[adapter] = weight_B.to(dtype) | |
return output_tensor | |
def _mixed_batch_forward( | |
self, x: torch.Tensor, *args: Any, adapter_names: list[str], **kwargs: Any | |
) -> torch.Tensor: | |
# This is a special method that handles the case when users pass the argument `adapter_names`. This is an | |
# extra argument that allows mixing different adapters in the same batch at inference time. | |
result = self.base_layer(x, *args, **kwargs) | |
unique_adapters = set(adapter_names) | |
sub_batch_indices_list = [] | |
for adapter in unique_adapters: | |
sub_batch_indices_list.append([index for index, item in enumerate(adapter_names) if item == adapter]) | |
for i, active_adapter in enumerate(unique_adapters): | |
if active_adapter == "__base__": | |
continue | |
if active_adapter not in self.lora_embedding_A.keys(): | |
continue | |
embedding_A = self.lora_embedding_A[active_adapter].T | |
embedding_B = self.lora_embedding_B[active_adapter].T | |
scaling = self.scaling[active_adapter] | |
# getting the sub-batch, passing it to LoRA layers and updating the corresponding indices of the linear | |
# layer output | |
sub_batch = x[sub_batch_indices_list[i]] | |
after_A = self._embed(sub_batch, embedding_A) | |
result[sub_batch_indices_list[i]] += (after_A @ embedding_B) * scaling | |
return result | |
def _embed(self, input: torch.Tensor, weight: torch.Tensor) -> torch.Tensor: | |
base_layer = self.get_base_layer() | |
return F.embedding( | |
input, | |
weight, | |
padding_idx=base_layer.padding_idx, | |
max_norm=base_layer.max_norm, | |
norm_type=base_layer.norm_type, | |
scale_grad_by_freq=base_layer.scale_grad_by_freq, | |
sparse=base_layer.sparse, | |
) | |
def forward(self, x: torch.Tensor, *args: Any, **kwargs: Any) -> torch.Tensor: | |
# TODO: no dtype conversion here, unlike in Linear, is that correct? | |
self._check_forward_args(x, *args, **kwargs) | |
adapter_names = kwargs.pop("adapter_names", None) | |
if self.disable_adapters: | |
if self.merged: | |
self.unmerge() | |
result = self.base_layer(x, *args, **kwargs) | |
elif adapter_names is not None: | |
result = self._mixed_batch_forward(x, *args, adapter_names=adapter_names, **kwargs) | |
elif self.merged: | |
result = self.base_layer(x, *args, **kwargs) | |
else: | |
result = self.base_layer(x, *args, **kwargs) | |
torch_result_dtype = result.dtype | |
for active_adapter in self.active_adapters: | |
if active_adapter not in self.lora_embedding_A: | |
continue | |
embedding_A = self.lora_embedding_A[active_adapter].T | |
embedding_B = self.lora_embedding_B[active_adapter].T | |
scaling = self.scaling[active_adapter] | |
if not self.use_dora[active_adapter]: | |
after_A = self._embed(x, embedding_A) | |
result = result + (after_A @ embedding_B) * scaling | |
else: | |
mag_norm_scale, dora_result = self.lora_magnitude_vector[active_adapter]( | |
x, | |
lora_A=embedding_A, | |
lora_B=embedding_B, | |
scaling=scaling, | |
base_layer=self.get_base_layer(), | |
embed_fn=self._embed, | |
) | |
result = mag_norm_scale * result + dora_result | |
result = result.to(torch_result_dtype) | |
return result | |
def __repr__(self) -> str: | |
rep = super().__repr__() | |
return "lora." + rep | |
class _ConvNd(nn.Module, LoraLayer): | |
# Lora implemented in a conv(2,3)d layer | |
def __init__( | |
self, | |
base_layer: nn.Module, | |
adapter_name: str, | |
r: int = 0, | |
lora_alpha: int = 1, | |
lora_dropout: float = 0.0, | |
init_lora_weights: Union[bool, str] = True, | |
use_rslora: bool = False, | |
use_dora: bool = False, | |
lora_bias: bool = False, | |
**kwargs, | |
) -> None: | |
super().__init__() | |
LoraLayer.__init__(self, base_layer) | |
self._active_adapter = adapter_name | |
self._kernel_dim = base_layer.weight.dim() | |
self.update_layer( | |
adapter_name, | |
r, | |
lora_alpha=lora_alpha, | |
lora_dropout=lora_dropout, | |
init_lora_weights=init_lora_weights, | |
use_rslora=use_rslora, | |
use_dora=use_dora, | |
lora_bias=lora_bias, | |
) | |
def update_layer( | |
self, adapter_name, r, lora_alpha, lora_dropout, init_lora_weights, use_rslora, use_dora, lora_bias | |
): | |
if r <= 0: | |
raise ValueError(f"`r` should be a positive integer value but the value passed is {r}") | |
self.r[adapter_name] = r | |
self.lora_alpha[adapter_name] = lora_alpha | |
if lora_dropout > 0.0: | |
lora_dropout_layer = nn.Dropout(p=lora_dropout) | |
else: | |
lora_dropout_layer = nn.Identity() | |
self.lora_dropout[adapter_name] = lora_dropout_layer | |
# Actual trainable parameters | |
base_layer = self.get_base_layer() | |
kernel_size = base_layer.kernel_size | |
stride = base_layer.stride | |
padding = base_layer.padding | |
conv_layer = type(base_layer) | |
out_kernel = out_stride = (1,) * (self._kernel_dim - 2) | |
self.lora_A[adapter_name] = conv_layer(self.in_features, r, kernel_size, stride, padding, bias=False) | |
self.lora_B[adapter_name] = conv_layer(r, self.out_features, out_kernel, out_stride, bias=lora_bias) | |
self.lora_bias[adapter_name] = lora_bias | |
if use_rslora: | |
self.scaling[adapter_name] = lora_alpha / math.sqrt(r) | |
else: | |
self.scaling[adapter_name] = lora_alpha / r | |
if init_lora_weights == "loftq": | |
self.loftq_init(adapter_name) | |
elif init_lora_weights: | |
self.reset_lora_parameters(adapter_name, init_lora_weights) | |
# call this before dora_init | |
self._move_adapter_to_device_of_base_layer(adapter_name) | |
if use_dora: | |
self.dora_init(adapter_name) | |
self.use_dora[adapter_name] = True | |
else: | |
self.use_dora[adapter_name] = False | |
self.set_adapter(self.active_adapters) | |
def _get_dora_factor_view(self): | |
return (-1,) + (1,) * (self._kernel_dim - 1) | |
def dora_init(self, adapter_name: str) -> None: | |
if self.lora_magnitude_vector is None: | |
# first dora layer being added, add lora_magnitude_vector to the list of learnable parameters | |
self.adapter_layer_names = self.adapter_layer_names[:] + ("lora_magnitude_vector",) | |
dora_layer_class = self._get_dora_layer_class() | |
dora_layer = dora_layer_class(fan_in_fan_out=False) | |
lora_A = self.lora_A[adapter_name].weight | |
lora_B = self.lora_B[adapter_name].weight | |
scaling = self.scaling[adapter_name] | |
dora_layer.update_layer(base_layer=self.get_base_layer(), lora_A=lora_A, lora_B=lora_B, scaling=scaling) | |
self.lora_magnitude_vector[adapter_name] = dora_layer | |
def _get_dora_layer_class(self) -> type[_DoraConvNdLayer]: | |
# Subclasses should override this method to return the appropriate DoraLayer class | |
raise NotImplementedError | |
def merge(self, safe_merge: bool = False, adapter_names: Optional[list[str]] = None) -> None: | |
""" | |
Merge the active adapter weights inside the base weights | |
Args: | |
safe_merge (`bool`, *optional*): | |
If True, the merge operation will be performed in a copy of the original weights and check for NaNs | |
before merging the weights. This is useful if you want to check if the merge operation will produce | |
NaNs. Defaults to `False`. | |
adapter_names (`list[str]`, *optional*): | |
The list of adapter names that should be merged. If None, all active adapters will be merged. Defaults | |
to `None`. | |
""" | |
adapter_names = check_adapters_to_merge(self, adapter_names) | |
if not adapter_names: | |
# no adapter to merge | |
return | |
for active_adapter in adapter_names: | |
if active_adapter in self.lora_A.keys(): | |
base_layer = self.get_base_layer() | |
if safe_merge: | |
# Note that safe_merge will be slower than the normal merge | |
# because of the copy operation. | |
orig_weights = base_layer.weight.data.clone() | |
delta_weight = self.get_delta_weight(active_adapter) | |
if not self.use_dora[active_adapter]: | |
orig_weights += delta_weight | |
else: | |
# handle dora | |
# since delta_weight already includes scaling, set it to 1 here | |
weight_norm = ( | |
self.lora_magnitude_vector[active_adapter] | |
.get_weight_norm(orig_weights, delta_weight, scaling=1) | |
.detach() | |
) | |
# We need to cache weight_norm because it has to be based on the original weights. We | |
# cannot calculate it on the fly based on the merged weights when unmerging because its a | |
# different value | |
self._cache_store(f"{active_adapter}-weight_norm", weight_norm) | |
dora_factor = self.lora_magnitude_vector[active_adapter].weight / weight_norm | |
orig_weights = dora_factor.view(*self._get_dora_factor_view()) * (orig_weights + delta_weight) | |
if not torch.isfinite(orig_weights).all(): | |
raise ValueError( | |
f"NaNs detected in the merged weights. The adapter {active_adapter} seems to be broken" | |
) | |
base_layer.weight.data = orig_weights | |
if self.lora_bias[active_adapter]: | |
new_bias = base_layer.bias + self.lora_B[active_adapter].bias | |
if not torch.isfinite(new_bias).all(): | |
raise ValueError( | |
f"NaNs detected in the merged weights. The adapter {active_adapter} seems to be broken" | |
) | |
base_layer.bias.data = new_bias | |
else: | |
delta_weight = self.get_delta_weight(active_adapter) | |
if not self.use_dora[active_adapter]: | |
base_layer.weight.data += delta_weight | |
else: | |
# handle dora | |
# since delta_weight already includes scaling, set it to 1 here | |
weight_norm = ( | |
self.lora_magnitude_vector[active_adapter] | |
.get_weight_norm(base_layer.weight, delta_weight, scaling=1) | |
.detach() | |
) | |
# We need to cache weight_norm because it has to be based on the original weights. We | |
# cannot calculate it on the fly based on the merged weights when unmerging because its a | |
# different value | |
self._cache_store(f"{active_adapter}-weight_norm", weight_norm) | |
dora_factor = self.lora_magnitude_vector[active_adapter].weight / weight_norm | |
new_weight = dora_factor.view(*self._get_dora_factor_view()) * ( | |
base_layer.weight.data + delta_weight | |
) | |
base_layer.weight.data = new_weight | |
if self.lora_bias[active_adapter]: | |
base_layer.bias.data += self.lora_B[active_adapter].bias | |
self.merged_adapters.append(active_adapter) | |
def unmerge(self) -> None: | |
""" | |
This method unmerges all merged adapter layers from the base weights. | |
""" | |
if not self.merged: | |
warnings.warn("Already unmerged. Nothing to do.") | |
return | |
while len(self.merged_adapters) > 0: | |
active_adapter = self.merged_adapters.pop() | |
if active_adapter in self.lora_A.keys(): | |
weight = self.get_base_layer().weight | |
delta_weight = self.get_delta_weight(active_adapter) | |
if not self.use_dora[active_adapter]: | |
weight.data -= delta_weight | |
else: | |
weight_norm = self._cache_pop(f"{active_adapter}-weight_norm") | |
dora_factor = self.lora_magnitude_vector[active_adapter].weight / weight_norm | |
weight_orig = weight.data / dora_factor.view(*self._get_dora_factor_view()) - delta_weight | |
weight.data = weight_orig | |
if self.lora_bias[active_adapter]: | |
self.get_base_layer().bias.data -= self.lora_B[active_adapter].bias | |
def get_delta_weight(self, adapter) -> torch.Tensor: | |
""" | |
Compute the delta weight for the given adapter. | |
Args: | |
adapter (str): | |
The name of the adapter for which the delta weight should be computed. | |
""" | |
device = self.lora_B[adapter].weight.device | |
dtype = self.lora_A[adapter].weight.dtype | |
# In case users wants to merge the adapter weights that are in | |
# (b)float16 while being on CPU, we need to cast the weights to float32, perform the merge and then cast back to | |
# (b)float16 because some CPUs have slow bf16/fp16 matmuls. | |
cast_to_fp32 = device.type == "cpu" and (dtype == torch.float16 or dtype == torch.bfloat16) | |
weight_A = self.lora_A[adapter].weight | |
weight_B = self.lora_B[adapter].weight | |
if cast_to_fp32: | |
weight_A = weight_A.float() | |
weight_B = weight_B.float() | |
# https://github.com/bmaltais/kohya_ss/blob/feb6728762a8f463d15ba936d189d4c3abfaa1ab/networks/lora.py#L117 | |
if self.get_base_layer().weight.size()[2:4] == (1, 1): | |
# conv2d 1x1 | |
output_tensor = (weight_B.squeeze(3).squeeze(2) @ weight_A.squeeze(3).squeeze(2)).unsqueeze(2).unsqueeze( | |
3 | |
) * self.scaling[adapter] | |
else: | |
output_tensor = ( | |
self.conv_fn( | |
weight_A.transpose(0, 1), | |
weight_B, | |
).transpose(0, 1) | |
* self.scaling[adapter] | |
) | |
if cast_to_fp32: | |
output_tensor = output_tensor.to(dtype=dtype) | |
# cast back the weights | |
self.lora_A[adapter].weight.data = weight_A.to(dtype) | |
self.lora_B[adapter].weight.data = weight_B.to(dtype) | |
return output_tensor | |
def forward(self, x: torch.Tensor, *args, **kwargs) -> torch.Tensor: | |
self._check_forward_args(x, *args, **kwargs) | |
adapter_names = kwargs.pop("adapter_names", None) | |
if self.disable_adapters: | |
if self.merged: | |
self.unmerge() | |
result = self.base_layer(x, *args, **kwargs) | |
elif adapter_names is not None: | |
result = self._mixed_batch_forward(x, *args, adapter_names=adapter_names, **kwargs) | |
elif self.merged: | |
result = self.base_layer(x, *args, **kwargs) | |
else: | |
result = self.base_layer(x, *args, **kwargs) | |
torch_result_dtype = result.dtype | |
for active_adapter in self.active_adapters: | |
if active_adapter not in self.lora_A.keys(): | |
continue | |
lora_A = self.lora_A[active_adapter] | |
lora_B = self.lora_B[active_adapter] | |
dropout = self.lora_dropout[active_adapter] | |
scaling = self.scaling[active_adapter] | |
x = x.to(lora_A.weight.dtype) | |
if not self.use_dora[active_adapter]: | |
result = result + lora_B(lora_A(dropout(x))) * scaling | |
else: | |
x = dropout(x) | |
result = result + self.lora_magnitude_vector[active_adapter]( | |
x, | |
lora_A=lora_A, | |
lora_B=lora_B, | |
scaling=scaling, | |
base_layer=self.get_base_layer(), | |
) | |
result = result.to(torch_result_dtype) | |
return result | |
def __repr__(self) -> str: | |
rep = super().__repr__() | |
return "lora." + rep | |
class Conv2d(_ConvNd): | |
# Lora implemented in a conv2d layer | |
def __init__(self, *args, **kwargs): | |
super().__init__(*args, **kwargs) | |
if not self._kernel_dim == 4: | |
raise ValueError(f"Conv2d layer kernel must have 4 dimensions, not {self._kernel_dim}") | |
self.conv_fn = F.conv2d | |
def _get_dora_layer_class(self): | |
return DoraConv2dLayer | |
class Conv3d(_ConvNd): | |
# Lora implemented in a conv3d layer | |
def __init__(self, *args, **kwargs): | |
super().__init__(*args, **kwargs) | |
if not self._kernel_dim == 5: | |
raise ValueError(f"Conv3d layer kernel must have 5 dimensions, not {self._kernel_dim}") | |
self.conv_fn = F.conv3d | |
def _get_dora_layer_class(self): | |
return DoraConv3dLayer | |
def dispatch_default( | |
target: torch.nn.Module, | |
adapter_name: str, | |
lora_config: LoraConfig, | |
**kwargs, | |
) -> Optional[torch.nn.Module]: | |
new_module = None | |
if isinstance(target, BaseTunerLayer): | |
target_base_layer = target.get_base_layer() | |
else: | |
target_base_layer = target | |
if isinstance(target_base_layer, torch.nn.Embedding): | |
embedding_kwargs = kwargs.copy() | |
embedding_kwargs.pop("fan_in_fan_out", None) | |
embedding_kwargs.update(lora_config.loftq_config) | |
new_module = Embedding(target, adapter_name, **embedding_kwargs) | |
elif isinstance(target_base_layer, torch.nn.Conv2d): | |
kwargs.update(lora_config.loftq_config) | |
new_module = Conv2d(target, adapter_name, **kwargs) | |
elif isinstance(target_base_layer, torch.nn.Conv3d): | |
kwargs.update(lora_config.loftq_config) | |
new_module = Conv3d(target, adapter_name, **kwargs) | |
elif isinstance(target_base_layer, torch.nn.Linear): | |
if kwargs["fan_in_fan_out"]: | |
warnings.warn( | |
"fan_in_fan_out is set to True but the target module is `torch.nn.Linear`. " | |
"Setting fan_in_fan_out to False." | |
) | |
kwargs["fan_in_fan_out"] = lora_config.fan_in_fan_out = False | |
kwargs.update(lora_config.loftq_config) | |
new_module = Linear(target, adapter_name, **kwargs) | |
elif isinstance(target_base_layer, Conv1D): | |
if not kwargs["fan_in_fan_out"]: | |
warnings.warn( | |
"fan_in_fan_out is set to False but the target module is `Conv1D`. " "Setting fan_in_fan_out to True." | |
) | |
kwargs["fan_in_fan_out"] = lora_config.fan_in_fan_out = True | |
kwargs.update(lora_config.loftq_config) | |
new_module = Linear(target, adapter_name, is_target_conv_1d_layer=True, **kwargs) | |
return new_module | |