wip - cross attention layer

This commit is contained in:
Brian Fitzgerald
2023-12-09 09:57:19 -06:00
parent fbcc9f51ba
commit a876244ae2
+32 -130
View File
@@ -68,22 +68,11 @@ def adain(feat: T) -> T:
return feat
class CrossAttention(nn.Module):
def forward(self, x, context=None, value=None, mask=None):
q = self.to_q(x)
context = default(context, x)
k = self.to_k(context)
if value is not None:
v = self.to_v(value)
del value
else:
v = self.to_v(context)
if mask is None:
out = optimized_attention(q, k, v, self.heads)
else:
out = optimized_attention_masked(q, k, v, self.heads, mask)
return self.to_out(out)
def sdpa(q: T, k: T, v: T, mask=None, heads: int = 8) -> T:
if mask:
return optimized_attention_masked(q, k, v, heads, mask)
else:
return optimized_attention(q, k, v, heads)
class SharedAttentionProcessor:
@@ -123,130 +112,44 @@ class SharedAttentionProcessor:
nn.Dropout(dropout),
)
def shifted_scaled_dot_product_attention(
self, attn, query: T, key: T, value: T
) -> T:
logits = torch.einsum("bhqd,bhkd->bhqk", query, key) * attn.scale
def shifted_scaled_dot_product_attention(self, query: T, key: T, value: T) -> T:
logits = torch.einsum("bhqd,bhkd->bhqk", query, key)
logits[:, :, :, query.shape[2] :] += self.args.shared_score_shift
probs = logits.softmax(-1)
return torch.einsum("bhqk,bhkd->bhqd", probs, value)
def shared_call(
self,
hidden_states,
encoder_hidden_states=None,
attention_mask=None,
):
residual = hidden_states
input_ndim = hidden_states.ndim
if input_ndim == 4:
batch_size, channel, height, width = hidden_states.shape
hidden_states = hidden_states.view(
batch_size, channel, height * width
).transpose(1, 2)
batch_size, sequence_length, _ = (
hidden_states.shape
if encoder_hidden_states is None
else encoder_hidden_states.shape
)
if attention_mask is not None:
attention_mask = prepare_attention_mask(
attention_mask, sequence_length, batch_size
)
# scaled_dot_product_attention expects attention_mask shape to be
# (batch, heads, source_length, target_length)
attention_mask = attention_mask.view(
batch_size, self.heads, -1, attention_mask.shape[-1]
)
if attn.group_norm is not None:
hidden_states = attn.group_norm(hidden_states.transpose(1, 2)).transpose(
1, 2
)
query = self.to_q(hidden_states)
key = self.to_k(hidden_states)
value = self.to_v(hidden_states)
inner_dim = key.shape[-1]
head_dim = inner_dim // attn.heads
query = query.view(batch_size, -1, attn.heads, head_dim).transpose(1, 2)
key = key.view(batch_size, -1, attn.heads, head_dim).transpose(1, 2)
value = value.view(batch_size, -1, attn.heads, head_dim).transpose(1, 2)
# if self.step >= self.start_inject:
if self.args.adain_queries:
query = adain(query)
if self.args.adain_keys:
key = adain(key)
if self.args.adain_values:
value = adain(value)
if self.args.share_attention:
key = concat_first(key, -2, scale=self.args.shared_score_scale)
value = concat_first(value, -2)
if self.args.shared_score_shift != 0:
hidden_states = self.shifted_scaled_dot_product_attention(
attn,
query,
key,
value,
)
else:
hidden_states = nnf.scaled_dot_product_attention(
query,
key,
value,
attn_mask=attention_mask,
dropout_p=0.0,
is_causal=False,
)
else:
hidden_states = nnf.scaled_dot_product_attention(
query,
key,
value,
attn_mask=attention_mask,
dropout_p=0.0,
is_causal=False,
)
# hidden_states = adain(hidden_states)
hidden_states = hidden_states.transpose(1, 2).reshape(
batch_size, -1, attn.heads * head_dim
)
hidden_states = hidden_states.to(query.dtype)
# linear proj
hidden_states = attn.to_out[0](hidden_states)
# dropout
hidden_states = attn.to_out[1](hidden_states)
if input_ndim == 4:
hidden_states = hidden_states.transpose(-1, -2).reshape(
batch_size, channel, height, width
)
if attn.residual_connection:
hidden_states = hidden_states + residual
hidden_states = hidden_states / attn.rescale_output_factor
return hidden_states
def forward(self, x, context=None, value=None, mask=None):
q = self.to_q(x)
query = self.to_q(x)
context = default(context, x)
k = self.to_k(context)
key = self.to_k(context)
v = self.to_v(x)
if value is not None:
v = self.to_v(value)
del value
else:
v = self.to_v(context)
if mask is None:
out = optimized_attention(q, k, v, self.heads)
if self.args.adain_queries:
query = adain(query)
if self.args.adain_keys:
key = adain(key)
if self.args.adain_values:
v = adain(v)
if self.args.share_attention:
key = concat_first(key, -2, scale=self.args.shared_score_scale)
v = concat_first(v, -2)
if self.args.shared_score_shift != 0:
x = self.shifted_scaled_dot_product_attention(
query,
key,
v,
)
else:
x = sdpa(query, key, v, mask, self.heads)
else:
out = optimized_attention_masked(q, k, v, self.heads, mask)
return self.to_out(out)
x = sdpa(query, key, v, mask, self.heads)
return x
def register_shared_norm(
model: ModelPatcher,
@@ -304,12 +207,11 @@ def _get_switch_vec(total_num_layers, level):
return vec
def init_attention_processors(pipeline, style_aligned_args: StyleAlignedArgs):
def init_attention_processors(model, style_aligned_args: StyleAlignedArgs):
attn_procs = {}
unet = pipeline.unet
number_of_self, number_of_cross = 0, 0
num_self_layers = len(
[name for name in unet.attn_processors.keys() if "attn1" in name]
[name for name in model.keys() if "attn1" in name]
)
if style_aligned_args is None:
only_self_vec = _get_switch_vec(num_self_layers, 1)
@@ -317,7 +219,7 @@ def init_attention_processors(pipeline, style_aligned_args: StyleAlignedArgs):
only_self_vec = _get_switch_vec(
num_self_layers, style_aligned_args.only_self_level
)
for i, name in enumerate(unet.attn_processors.keys()):
for i, name in enumerate(model.keys()):
is_self_attention = "attn1" in name
if is_self_attention:
number_of_self += 1