Files
kijai-ComfyUI-WanVideoWrapper/custom_linear.py
T
kijai 9fa4140159 Make lora torch.compile optional for unmerged lora application
This change has caused issues especially with LoRAs that have dynamic rank. Will now be disabled by default, to allow full graph with unmerged LoRAs the option to allow compile is available in the Torch Compile Settings -node
2025-11-04 01:34:51 +02:00

170 lines
6.9 KiB
Python

import torch
import torch.nn as nn
from accelerate import init_empty_weights
#based on https://github.com/huggingface/diffusers/blob/main/src/diffusers/quantizers/gguf/utils.py
def _replace_linear(model, compute_dtype, state_dict, prefix="", patches=None, scale_weights=None, compile_args=None):
has_children = list(model.children())
if not has_children:
return
allow_compile = False
for name, module in model.named_children():
if compile_args is not None:
allow_compile = compile_args.get("allow_unmerged_lora_compile", False)
module_prefix = prefix + name + "."
module_prefix = module_prefix.replace("_orig_mod.", "")
_replace_linear(module, compute_dtype, state_dict, module_prefix, patches, scale_weights, compile_args)
if isinstance(module, nn.Linear) and "loras" not in module_prefix:
in_features = state_dict[module_prefix + "weight"].shape[1]
out_features = state_dict[module_prefix + "weight"].shape[0]
if scale_weights is not None:
scale_key = f"{module_prefix}scale_weight"
with init_empty_weights():
model._modules[name] = CustomLinear(
in_features,
out_features,
module.bias is not None,
compute_dtype=compute_dtype,
scale_weight=scale_weights.get(scale_key) if scale_weights else None,
allow_compile=allow_compile
)
model._modules[name].source_cls = type(module)
model._modules[name].requires_grad_(False)
return model
def set_lora_params(module, patches, module_prefix="", device=torch.device("cpu")):
remove_lora_from_module(module)
# Recursively set lora_diffs and lora_strengths for all CustomLinear layers
for name, child in module.named_children():
params = list(child.parameters())
if params:
device = params[0].device
else:
device = torch.device("cpu")
child_prefix = (f"{module_prefix}{name}.")
set_lora_params(child, patches, child_prefix, device)
if isinstance(module, CustomLinear):
key = f"diffusion_model.{module_prefix}weight"
patch = patches.get(key, [])
#print(f"Processing LoRA patches for {key}: {len(patch)} patches found")
if len(patch) == 0:
key = key.replace("_orig_mod.", "")
patch = patches.get(key, [])
#print(f"Processing LoRA patches for {key}: {len(patch)} patches found")
if len(patch) != 0:
lora_diffs = []
for p in patch:
lora_obj = p[1]
if "head" in key:
continue # For now skip LoRA for head layers
elif hasattr(lora_obj, "weights"):
lora_diffs.append(lora_obj.weights)
elif isinstance(lora_obj, tuple) and lora_obj[0] == "diff":
lora_diffs.append(lora_obj[1])
else:
continue
lora_strengths = [p[0] for p in patch]
module.set_lora_diffs(lora_diffs, device=device)
module.lora_strengths = lora_strengths
module.step = 0 # Initialize step for LoRA scheduling
class CustomLinear(nn.Linear):
def __init__(
self,
in_features,
out_features,
bias=False,
compute_dtype=None,
device=None,
scale_weight=None,
allow_compile=False
) -> None:
super().__init__(in_features, out_features, bias, device)
self.compute_dtype = compute_dtype
self.lora_diffs = []
self.step = 0
self.scale_weight = scale_weight
self.lora_strengths = []
self.allow_compile = allow_compile
if not allow_compile:
self._get_weight_with_lora = torch.compiler.disable()(self._get_weight_with_lora)
def set_lora_diffs(self, lora_diffs, device=torch.device("cpu")):
self.lora_diffs = []
for i, diff in enumerate(lora_diffs):
if len(diff) > 1:
self.register_buffer(f"lora_diff_{i}_0", diff[0].to(device))
self.register_buffer(f"lora_diff_{i}_1", diff[1].to(device))
setattr(self, f"lora_diff_{i}_2", diff[2])
self.lora_diffs.append((f"lora_diff_{i}_0", f"lora_diff_{i}_1", f"lora_diff_{i}_2"))
else:
self.register_buffer(f"lora_diff_{i}_0", diff[0].to(device))
self.lora_diffs.append(f"lora_diff_{i}_0")
def _get_weight_with_lora(self, weight):
"""Apply LoRA outside compiled region"""
if not hasattr(self, "lora_diff_0_0"):
return weight
for lora_diff_names, lora_strength in zip(self.lora_diffs, self.lora_strengths):
if isinstance(lora_strength, list):
lora_strength = lora_strength[self.step]
if lora_strength == 0.0:
continue
elif lora_strength == 0.0:
continue
if isinstance(lora_diff_names, tuple):
lora_diff_0 = getattr(self, lora_diff_names[0])
lora_diff_1 = getattr(self, lora_diff_names[1])
lora_diff_2 = getattr(self, lora_diff_names[2])
patch_diff = torch.mm(
lora_diff_0.flatten(start_dim=1),
lora_diff_1.flatten(start_dim=1)
).reshape(weight.shape)
alpha = lora_diff_2 / lora_diff_1.shape[0] if lora_diff_2 is not None else 1.0
scale = lora_strength * alpha
weight = weight.add(patch_diff, alpha=scale)
else:
lora_diff = getattr(self, lora_diff_names)
weight = weight.add(lora_diff, alpha=lora_strength)
return weight
def forward(self, input):
if self.bias is not None:
bias = self.bias.to(input)
else:
bias = None
weight = self.weight.to(input)
if self.scale_weight is not None:
if weight.numel() < input.numel():
weight = weight * self.scale_weight
else:
input = input * self.scale_weight
weight = self._get_weight_with_lora(weight)
if self.compute_dtype is not None:
weight = weight.to(self.compute_dtype)
return torch.nn.functional.linear(input, weight, bias)
def remove_lora_from_module(module):
for name, submodule in module.named_modules():
if hasattr(submodule, "lora_diffs"):
for i in range(len(submodule.lora_diffs)):
if hasattr(submodule, f"lora_diff_{i}_0"):
delattr(submodule, f"lora_diff_{i}_0")
if hasattr(submodule, f"lora_diff_{i}_1"):
delattr(submodule, f"lora_diff_{i}_1")
if hasattr(submodule, f"lora_diff_{i}_2"):
delattr(submodule, f"lora_diff_{i}_2")