ramimu's picture
Upload 586 files
1c72248 verified
#based off https://github.com/catid/dora/blob/main/dora.py
import math
import torch
import torch.nn as nn
import torch.nn.functional as F
from typing import TYPE_CHECKING, Union, List
from optimum.quanto import QBytesTensor, QTensor
from toolkit.network_mixins import ToolkitModuleMixin, ExtractableModuleMixin
if TYPE_CHECKING:
from toolkit.lora_special import LoRASpecialNetwork
# diffusers specific stuff
LINEAR_MODULES = [
'Linear',
'LoRACompatibleLinear'
# 'GroupNorm',
]
CONV_MODULES = [
'Conv2d',
'LoRACompatibleConv'
]
def transpose(weight, fan_in_fan_out):
if not fan_in_fan_out:
return weight
if isinstance(weight, torch.nn.Parameter):
return torch.nn.Parameter(weight.T)
return weight.T
class DoRAModule(ToolkitModuleMixin, ExtractableModuleMixin, torch.nn.Module):
# def __init__(self, d_in, d_out, rank=4, weight=None, bias=None):
def __init__(
self,
lora_name,
org_module: torch.nn.Module,
multiplier=1.0,
lora_dim=4,
alpha=1,
dropout=None,
rank_dropout=None,
module_dropout=None,
network: 'LoRASpecialNetwork' = None,
use_bias: bool = False,
**kwargs
):
self.can_merge_in = False
"""if alpha == 0 or None, alpha is rank (no scaling)."""
ToolkitModuleMixin.__init__(self, network=network)
torch.nn.Module.__init__(self)
self.lora_name = lora_name
self.scalar = torch.tensor(1.0)
self.lora_dim = lora_dim
if org_module.__class__.__name__ in CONV_MODULES:
raise NotImplementedError("Convolutional layers are not supported yet")
if type(alpha) == torch.Tensor:
alpha = alpha.detach().float().numpy() # without casting, bf16 causes error
alpha = self.lora_dim if alpha is None or alpha == 0 else alpha
self.scale = alpha / self.lora_dim
# self.register_buffer("alpha", torch.tensor(alpha)) # 定数として扱える eng: treat as constant
self.multiplier: Union[float, List[float]] = multiplier
# wrap the original module so it doesn't get weights updated
self.org_module = [org_module]
self.dropout = dropout
self.rank_dropout = rank_dropout
self.module_dropout = module_dropout
self.is_checkpointing = False
d_out = org_module.out_features
d_in = org_module.in_features
std_dev = 1 / torch.sqrt(torch.tensor(self.lora_dim).float())
# self.lora_up = nn.Parameter(torch.randn(d_out, self.lora_dim) * std_dev) # lora_A
# self.lora_down = nn.Parameter(torch.zeros(self.lora_dim, d_in)) # lora_B
self.lora_up = nn.Linear(self.lora_dim, d_out, bias=False) # lora_B
# self.lora_up.weight.data = torch.randn_like(self.lora_up.weight.data) * std_dev
self.lora_up.weight.data = torch.zeros_like(self.lora_up.weight.data)
# 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=False)
self.lora_down = nn.Linear(d_in, self.lora_dim, bias=False) # lora_A
# self.lora_down.weight.data = torch.zeros_like(self.lora_down.weight.data)
self.lora_down.weight.data = torch.randn_like(self.lora_down.weight.data) * std_dev
# m = Magnitude column-wise across output dimension
weight = self.get_orig_weight()
weight = weight.to(self.lora_up.weight.device, dtype=self.lora_up.weight.dtype)
lora_weight = self.lora_up.weight @ self.lora_down.weight
weight_norm = self._get_weight_norm(weight, lora_weight)
self.magnitude = nn.Parameter(weight_norm.detach().clone(), requires_grad=True)
def apply_to(self):
self.org_forward = self.org_module[0].forward
self.org_module[0].forward = self.forward
# del self.org_module
def get_orig_weight(self):
weight = self.org_module[0].weight
if isinstance(weight, QTensor) or isinstance(weight, QBytesTensor):
return weight.dequantize().data.detach()
else:
return weight.data.detach()
def get_orig_bias(self):
if hasattr(self.org_module[0], 'bias') and self.org_module[0].bias is not None:
return self.org_module[0].bias.data.detach()
return None
# def dora_forward(self, x, *args, **kwargs):
# lora = torch.matmul(self.lora_A, self.lora_B)
# adapted = self.get_orig_weight() + lora
# column_norm = adapted.norm(p=2, dim=0, keepdim=True)
# norm_adapted = adapted / column_norm
# calc_weights = self.magnitude * norm_adapted
# return F.linear(x, calc_weights, self.get_orig_bias())
def _get_weight_norm(self, weight, scaled_lora_weight) -> torch.Tensor:
# calculate L2 norm of weight matrix, column-wise
weight = weight + scaled_lora_weight.to(weight.device)
weight_norm = torch.linalg.norm(weight, dim=1)
return weight_norm
def apply_dora(self, x, scaled_lora_weight):
# ref https://github.com/huggingface/peft/blob/1e6d1d73a0850223b0916052fd8d2382a90eae5a/src/peft/tuners/lora/layer.py#L192
# lora weight is already scaled
# magnitude = self.lora_magnitude_vector[active_adapter]
weight = self.get_orig_weight()
weight = weight.to(scaled_lora_weight.device, dtype=scaled_lora_weight.dtype)
weight_norm = self._get_weight_norm(weight, scaled_lora_weight)
# see section 4.3 of DoRA (https://arxiv.org/abs/2402.09353)
# "[...] we suggest treating ||V +∆V ||_c in
# Eq. (5) as a constant, thereby detaching it from the gradient
# graph. This means that while ||V + ∆V ||_c dynamically
# reflects the updates of ∆V , it won’t receive any gradient
# during backpropagation"
weight_norm = weight_norm.detach()
dora_weight = transpose(weight + scaled_lora_weight, False)
return (self.magnitude / weight_norm - 1).view(1, -1) * F.linear(x.to(dora_weight.dtype), dora_weight)