implement CrossAttentionAdapter using chain operations

This commit is contained in:
Pierre Chapuis 2023-09-08 18:51:54 +02:00
parent 43075f60b0
commit dc2c3e0163
2 changed files with 108 additions and 174 deletions

View file

@ -1,14 +1,16 @@
from enum import IntEnum
from functools import partial
from typing import Generic, TypeVar, Any
from typing import Generic, TypeVar, Any, Callable
from torch import Tensor, as_tensor, cat, zeros_like, device as Device, dtype as DType
from PIL import Image
from refiners.fluxion.adapters.adapter import Adapter
from refiners.fluxion.adapters.lora import Lora
from refiners.foundationals.clip.image_encoder import CLIPImageEncoder
from refiners.foundationals.latent_diffusion.stable_diffusion_1.unet import SD1UNet
from refiners.foundationals.latent_diffusion.stable_diffusion_xl.unet import SDXLUNet
from refiners.fluxion.layers.module import Module
from refiners.fluxion.layers.attentions import ScaledDotProductAttention
from refiners.fluxion.utils import image_to_tensor
import refiners.fluxion.layers as fl
@ -48,133 +50,8 @@ class _CrossAttnIndex(IntEnum):
IMG_CROSS_ATTN = 1 # image cross-attention
# Fluxion's Attention layer drop-in replacement implementing Decoupled Cross-Attention
class IPAttention(fl.Chain):
structural_attrs = [
"embedding_dim",
"text_sequence_length",
"image_sequence_length",
"scale",
"num_heads",
"heads_dim",
"key_embedding_dim",
"value_embedding_dim",
"inner_dim",
"use_bias",
"is_causal",
]
def __init__(
self,
embedding_dim: int,
text_sequence_length: int = 77,
image_sequence_length: int = 4,
scale: float = 1.0,
num_heads: int = 1,
key_embedding_dim: int | None = None,
value_embedding_dim: int | None = None,
inner_dim: int | None = None,
use_bias: bool = True,
is_causal: bool | None = None,
device: Device | str | None = None,
dtype: DType | None = None,
) -> None:
assert (
embedding_dim % num_heads == 0
), f"embedding_dim {embedding_dim} must be divisible by num_heads {num_heads}"
self.embedding_dim = embedding_dim
self.text_sequence_length = text_sequence_length
self.image_sequence_length = image_sequence_length
self.scale = scale
self.num_heads = num_heads
self.heads_dim = embedding_dim // num_heads
self.key_embedding_dim = key_embedding_dim or embedding_dim
self.value_embedding_dim = value_embedding_dim or embedding_dim
self.inner_dim = inner_dim or embedding_dim
self.use_bias = use_bias
self.is_causal = is_causal
super().__init__(
fl.Distribute(
# Note: the same query is used for image cross-attention as for text cross-attention
fl.Linear(
in_features=self.embedding_dim,
out_features=self.inner_dim,
bias=self.use_bias,
device=device,
dtype=dtype,
), # Wq
fl.Parallel(
fl.Chain(
fl.Slicing(dim=1, start=0, length=text_sequence_length),
fl.Linear(
in_features=self.key_embedding_dim,
out_features=self.inner_dim,
bias=self.use_bias,
device=device,
dtype=dtype,
), # Wk
),
fl.Chain(
fl.Slicing(dim=1, start=text_sequence_length, length=image_sequence_length),
fl.Linear(
in_features=self.key_embedding_dim,
out_features=self.inner_dim,
bias=self.use_bias,
device=device,
dtype=dtype,
), # Wk'
),
),
fl.Parallel(
fl.Chain(
fl.Slicing(dim=1, start=0, length=text_sequence_length),
fl.Linear(
in_features=self.key_embedding_dim,
out_features=self.inner_dim,
bias=self.use_bias,
device=device,
dtype=dtype,
), # Wv
),
fl.Chain(
fl.Slicing(dim=1, start=text_sequence_length, length=image_sequence_length),
fl.Linear(
in_features=self.key_embedding_dim,
out_features=self.inner_dim,
bias=self.use_bias,
device=device,
dtype=dtype,
), # Wv'
),
),
),
fl.Sum(
fl.Chain(
fl.Lambda(func=partial(self.select_qkv, index=_CrossAttnIndex.TXT_CROSS_ATTN)),
ScaledDotProductAttention(num_heads=num_heads, is_causal=is_causal),
),
fl.Chain(
fl.Lambda(func=partial(self.select_qkv, index=_CrossAttnIndex.IMG_CROSS_ATTN)),
ScaledDotProductAttention(num_heads=num_heads, is_causal=is_causal),
fl.Lambda(func=self.scale_outputs),
),
),
fl.Linear(
in_features=self.inner_dim,
out_features=self.embedding_dim,
bias=True,
device=device,
dtype=dtype,
),
)
def select_qkv(
self, query: Tensor, keys: tuple[Tensor, Tensor], values: tuple[Tensor, Tensor], index: _CrossAttnIndex
) -> tuple[Tensor, Tensor, Tensor]:
return (query, keys[index.value], values[index.value])
def scale_outputs(self, x: Tensor) -> Tensor:
return x * self.scale
class InjectionPoint(fl.Chain):
pass
class CrossAttentionAdapter(fl.Chain, Adapter[fl.Attention]):
@ -190,46 +67,100 @@ class CrossAttentionAdapter(fl.Chain, Adapter[fl.Attention]):
self.text_sequence_length = text_sequence_length
self.image_sequence_length = image_sequence_length
self.scale = scale
with self.setup_adapter(target):
super().__init__(
IPAttention(
embedding_dim=target.embedding_dim,
text_sequence_length=text_sequence_length,
image_sequence_length=image_sequence_length,
scale=scale,
num_heads=target.num_heads,
key_embedding_dim=target.key_embedding_dim,
value_embedding_dim=target.value_embedding_dim,
inner_dim=target.inner_dim,
use_bias=target.use_bias,
is_causal=target.is_causal,
fl.Distribute(
# Note: the same query is used for image cross-attention as for text cross-attention
InjectionPoint(), # Wq
fl.Parallel(
fl.Chain(
fl.Slicing(dim=1, start=0, length=text_sequence_length),
InjectionPoint(), # Wk
),
fl.Chain(
fl.Slicing(dim=1, start=text_sequence_length, length=image_sequence_length),
fl.Linear(
in_features=self.target.key_embedding_dim,
out_features=self.target.inner_dim,
bias=self.target.use_bias,
device=target.device,
dtype=target.dtype,
)
), # Wk'
),
),
fl.Parallel(
fl.Chain(
fl.Slicing(dim=1, start=0, length=text_sequence_length),
InjectionPoint(), # Wv
),
fl.Chain(
fl.Slicing(dim=1, start=text_sequence_length, length=image_sequence_length),
fl.Linear(
in_features=self.target.key_embedding_dim,
out_features=self.target.inner_dim,
bias=self.target.use_bias,
device=target.device,
dtype=target.dtype,
), # Wv'
),
),
),
fl.Sum(
fl.Chain(
fl.Lambda(func=partial(self.select_qkv, index=_CrossAttnIndex.TXT_CROSS_ATTN)),
ScaledDotProductAttention(num_heads=target.num_heads, is_causal=target.is_causal),
),
fl.Chain(
fl.Lambda(func=partial(self.select_qkv, index=_CrossAttnIndex.IMG_CROSS_ATTN)),
ScaledDotProductAttention(num_heads=target.num_heads, is_causal=target.is_causal),
fl.Lambda(func=self.scale_outputs),
),
),
InjectionPoint(), # proj
)
def get_parameter_name(self, matrix: str, bias: bool = False) -> str:
match matrix:
case "wq":
index = 0
case "wk":
index = 1
case "wk_prime":
index = 2
case "wv":
index = 3
case "wv_prime":
index = 4
case "proj":
index = 5
case _:
raise ValueError(f"Unexpected matrix name {matrix}")
def select_qkv(
self, query: Tensor, keys: tuple[Tensor, Tensor], values: tuple[Tensor, Tensor], index: _CrossAttnIndex
) -> tuple[Tensor, Tensor, Tensor]:
return (query, keys[index.value], values[index.value])
linear = list(self.IPAttention.layers(fl.Linear))[index]
param = getattr(linear, "bias" if bias else "weight")
name = next((n for n, p in self.named_parameters() if id(p) == id(param)), None)
assert name is not None
return name
def scale_outputs(self, x: Tensor) -> Tensor:
return x * self.scale
def _predicate(self, k: type[Module]) -> Callable[[fl.Module, fl.Chain], bool]:
def f(m: fl.Module, _: fl.Chain) -> bool:
if isinstance(m, Lora): # do not adapt LoRAs
raise StopIteration
return isinstance(m, k)
return f
def _target_linears(self) -> list[fl.Linear]:
return [m for m, _ in self.target.walk(self._predicate(fl.Linear)) if isinstance(m, fl.Linear)]
def inject(self: "CrossAttentionAdapter", parent: fl.Chain | None = None) -> "CrossAttentionAdapter":
linears = self._target_linears()
assert len(linears) == 4 # Wq, Wk, Wv and Proj
injection_points = list(self.layers(InjectionPoint))
assert len(injection_points) == 4
for linear, ip in zip(linears, injection_points):
ip.append(linear)
assert len(ip) == 1
return super().inject(parent)
def eject(self) -> None:
injection_points = list(self.layers(InjectionPoint))
assert len(injection_points) == 4
for ip in injection_points:
ip.pop()
assert len(ip) == 0
super().eject()
class IPAdapter(Generic[T], fl.Chain, Adapter[T]):
@ -265,17 +196,6 @@ class IPAdapter(Generic[T], fl.Chain, Adapter[T]):
continue
cross_attn_state_dict[k.removeprefix(prefix)] = v
# Retrieve original (frozen) cross-attention weights
# Note: this assumes the target UNet has already loaded weights
cross_attn_linears = list(cross_attn.target.layers(fl.Linear))
assert len(cross_attn_linears) == 4 # Wq, Wk, Wv and Proj
cross_attn_state_dict[cross_attn.get_parameter_name("wq")] = cross_attn_linears[0].weight
cross_attn_state_dict[cross_attn.get_parameter_name("wk")] = cross_attn_linears[1].weight
cross_attn_state_dict[cross_attn.get_parameter_name("wv")] = cross_attn_linears[2].weight
cross_attn_state_dict[cross_attn.get_parameter_name("proj")] = cross_attn_linears[3].weight
cross_attn_state_dict[cross_attn.get_parameter_name("proj", bias=True)] = cross_attn_linears[3].bias
cross_attn.load_state_dict(state_dict=cross_attn_state_dict)
def inject(self: "TIPAdapter", parent: fl.Chain | None = None) -> "TIPAdapter":

View file

@ -0,0 +1,14 @@
import refiners.fluxion.layers as fl
from refiners.foundationals.latent_diffusion.image_prompt import CrossAttentionAdapter
def test_cross_attention_adapter() -> None:
base = fl.Chain(fl.Attention(embedding_dim=4))
adapter = CrossAttentionAdapter(base.Attention).inject()
assert list(base) == [adapter]
adapter.eject()
assert len(base) == 1
assert isinstance(base[0], fl.Attention)