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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