Unify attention mechanism in single and joint attention blocks

This commit is contained in:
filipstrand 2024-12-28 07:18:17 +01:00
parent f0e82ad67f
commit 9954e7fb45
4 changed files with 120 additions and 86 deletions

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@ -0,0 +1,59 @@
import mlx.core as mx
from mlx import nn
from mlx.core.fast import scaled_dot_product_attention
class AttentionUtils:
@staticmethod
def process_qkv(
hidden_states: mx.array,
to_q: nn.Linear,
to_k: nn.Linear,
to_v: nn.Linear,
norm_q: nn.RMSNorm,
norm_k: nn.RMSNorm,
num_heads: int,
head_dim: int,
):
query = to_q(hidden_states)
key = to_k(hidden_states)
value = to_v(hidden_states)
# Reshape and transpose
query = mx.transpose(mx.reshape(query, (1, -1, num_heads, head_dim)), (0, 2, 1, 3))
key = mx.transpose(mx.reshape(key, (1, -1, num_heads, head_dim)), (0, 2, 1, 3))
value = mx.transpose(mx.reshape(value, (1, -1, num_heads, head_dim)), (0, 2, 1, 3))
# Apply normalization
query = norm_q(query)
key = norm_k(key)
return query, key, value
@staticmethod
def compute_attention(
query: mx.array,
key: mx.array,
value: mx.array,
batch_size: int,
num_heads: int,
head_dim: int
) -> mx.array: # fmt: off
scale = 1 / mx.sqrt(query.shape[-1])
hidden_states = scaled_dot_product_attention(query, key, value, scale=scale)
hidden_states = mx.transpose(hidden_states, (0, 2, 1, 3))
hidden_states = mx.reshape(
hidden_states,
(batch_size, -1, num_heads * head_dim),
)
return hidden_states
@staticmethod
def apply_rope(xq: mx.array, xk: mx.array, freqs_cis: mx.array):
xq_ = xq.astype(mx.float32).reshape(*xq.shape[:-1], -1, 1, 2)
xk_ = xk.astype(mx.float32).reshape(*xk.shape[:-1], -1, 1, 2)
xq_out = freqs_cis[..., 0] * xq_[..., 0] + freqs_cis[..., 1] * xq_[..., 1]
xk_out = freqs_cis[..., 0] * xk_[..., 0] + freqs_cis[..., 1] * xk_[..., 1]
return xq_out.reshape(*xq.shape).astype(mx.float32), xk_out.reshape(*xk.shape).astype(mx.float32)

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@ -1,15 +1,16 @@
import mlx.core as mx
from mlx import nn
from mlx.core.fast import scaled_dot_product_attention
from mflux.models.transformer.common.attention_utils import AttentionUtils
class JointAttention(nn.Module):
head_dimension = 128
batch_size = 1
num_heads = 24
def __init__(self):
super().__init__()
self.head_dimension = 128
self.batch_size = 1
self.num_heads = 24
self.to_q = nn.Linear(3072, 3072)
self.to_k = nn.Linear(3072, 3072)
self.to_v = nn.Linear(3072, 3072)
@ -29,51 +30,42 @@ class JointAttention(nn.Module):
encoder_hidden_states: mx.array,
image_rotary_emb: mx.array,
) -> (mx.array, mx.array):
query = self.to_q(hidden_states)
key = self.to_k(hidden_states)
value = self.to_v(hidden_states)
query = mx.transpose(mx.reshape(query, (1, -1, 24, 128)), (0, 2, 1, 3))
key = mx.transpose(mx.reshape(key, (1, -1, 24, 128)), (0, 2, 1, 3))
value = mx.transpose(mx.reshape(value, (1, -1, 24, 128)), (0, 2, 1, 3))
query = self.norm_q(query)
key = self.norm_k(key)
encoder_hidden_states_query_proj = self.add_q_proj(encoder_hidden_states)
encoder_hidden_states_key_proj = self.add_k_proj(encoder_hidden_states)
encoder_hidden_states_value_proj = self.add_v_proj(encoder_hidden_states)
encoder_hidden_states_query_proj = mx.transpose(
mx.reshape(encoder_hidden_states_query_proj, (1, -1, 24, 128)),
(0, 2, 1, 3),
query, key, value = AttentionUtils.process_qkv(
hidden_states=hidden_states,
to_q=self.to_q,
to_k=self.to_k,
to_v=self.to_v,
norm_q=self.norm_q,
norm_k=self.norm_k,
num_heads=self.num_heads,
head_dim=self.head_dimension,
)
encoder_hidden_states_key_proj = mx.transpose(
mx.reshape(encoder_hidden_states_key_proj, (1, -1, 24, 128)),
(0, 2, 1, 3),
)
encoder_hidden_states_value_proj = mx.transpose(
mx.reshape(encoder_hidden_states_value_proj, (1, -1, 24, 128)),
(0, 2, 1, 3),
enc_query, enc_key, enc_value = AttentionUtils.process_qkv(
hidden_states=encoder_hidden_states,
to_q=self.add_q_proj,
to_k=self.add_k_proj,
to_v=self.add_v_proj,
norm_q=self.norm_added_q,
norm_k=self.norm_added_k,
num_heads=self.num_heads,
head_dim=self.head_dimension,
)
encoder_hidden_states_query_proj = self.norm_added_q(encoder_hidden_states_query_proj)
encoder_hidden_states_key_proj = self.norm_added_k(encoder_hidden_states_key_proj)
query = mx.concatenate([enc_query, query], axis=2)
key = mx.concatenate([enc_key, key], axis=2)
value = mx.concatenate([enc_value, value], axis=2)
query = mx.concatenate([encoder_hidden_states_query_proj, query], axis=2)
key = mx.concatenate([encoder_hidden_states_key_proj, key], axis=2)
value = mx.concatenate([encoder_hidden_states_value_proj, value], axis=2)
query, key = AttentionUtils.apply_rope(xq=query, xk=key, freqs_cis=image_rotary_emb)
query, key = JointAttention.apply_rope(query, key, image_rotary_emb)
scale = 1 / mx.sqrt(query.shape[-1])
hidden_states = scaled_dot_product_attention(query, key, value, scale=scale)
hidden_states = mx.transpose(hidden_states, (0, 2, 1, 3))
hidden_states = mx.reshape(
hidden_states,
(self.batch_size, -1, self.num_heads * self.head_dimension),
hidden_states = AttentionUtils.compute_attention(
query=query,
key=key,
value=value,
batch_size=self.batch_size,
num_heads=self.num_heads,
head_dim=self.head_dimension,
)
encoder_hidden_states, hidden_states = (
hidden_states[:, : encoder_hidden_states.shape[1]],
hidden_states[:, encoder_hidden_states.shape[1] :],
@ -83,11 +75,3 @@ class JointAttention(nn.Module):
encoder_hidden_states = self.to_add_out(encoder_hidden_states)
return hidden_states, encoder_hidden_states
@staticmethod
def apply_rope(xq: mx.array, xk: mx.array, freqs_cis: mx.array):
xq_ = xq.astype(mx.float32).reshape(*xq.shape[:-1], -1, 1, 2)
xk_ = xk.astype(mx.float32).reshape(*xk.shape[:-1], -1, 1, 2)
xq_out = freqs_cis[..., 0] * xq_[..., 0] + freqs_cis[..., 1] * xq_[..., 1]
xk_out = freqs_cis[..., 0] * xk_[..., 0] + freqs_cis[..., 1] * xk_[..., 1]
return xq_out.reshape(*xq.shape).astype(mx.float32), xk_out.reshape(*xk.shape).astype(mx.float32)

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@ -1,50 +1,41 @@
import mlx.core as mx
from mlx import nn
from mlx.core.fast import scaled_dot_product_attention
from mflux.models.transformer.common.attention_utils import AttentionUtils
class SingleBlockAttention(nn.Module):
head_dimension = 128
batch_size = 1
num_heads = 24
def __init__(self):
super().__init__()
self.head_dimension = 128
self.batch_size = 1
self.num_heads = 24
self.to_q = nn.Linear(3072, 3072)
self.to_k = nn.Linear(3072, 3072)
self.to_v = nn.Linear(3072, 3072)
self.norm_q = nn.RMSNorm(128)
self.norm_k = nn.RMSNorm(128)
def __call__(self, hidden_states: mx.array, image_rotary_emb: mx.array) -> (mx.array, mx.array):
query = self.to_q(hidden_states)
key = self.to_k(hidden_states)
value = self.to_v(hidden_states)
query = mx.transpose(mx.reshape(query, (1, -1, 24, 128)), (0, 2, 1, 3))
key = mx.transpose(mx.reshape(key, (1, -1, 24, 128)), (0, 2, 1, 3))
value = mx.transpose(mx.reshape(value, (1, -1, 24, 128)), (0, 2, 1, 3))
query = self.norm_q(query)
key = self.norm_k(key)
query, key = SingleBlockAttention.apply_rope(query, key, image_rotary_emb)
scale = 1 / mx.sqrt(query.shape[-1])
hidden_states = scaled_dot_product_attention(query, key, value, scale=scale)
hidden_states = mx.transpose(hidden_states, (0, 2, 1, 3))
hidden_states = mx.reshape(
hidden_states,
(self.batch_size, -1, self.num_heads * self.head_dimension),
def __call__(self, hidden_states: mx.array, image_rotary_emb: mx.array) -> mx.array:
query, key, value = AttentionUtils.process_qkv(
hidden_states=hidden_states,
to_q=self.to_q,
to_k=self.to_k,
to_v=self.to_v,
norm_q=self.norm_q,
norm_k=self.norm_k,
num_heads=self.num_heads,
head_dim=self.head_dimension,
)
return hidden_states
query, key = AttentionUtils.apply_rope(xq=query, xk=key, freqs_cis=image_rotary_emb)
@staticmethod
def apply_rope(xq: mx.array, xk: mx.array, freqs_cis: mx.array):
xq_ = xq.astype(mx.float32).reshape(*xq.shape[:-1], -1, 1, 2)
xk_ = xk.astype(mx.float32).reshape(*xk.shape[:-1], -1, 1, 2)
xq_out = freqs_cis[..., 0] * xq_[..., 0] + freqs_cis[..., 1] * xq_[..., 1]
xk_out = freqs_cis[..., 0] * xk_[..., 0] + freqs_cis[..., 1] * xk_[..., 1]
return xq_out.reshape(*xq.shape).astype(mx.float32), xk_out.reshape(*xk.shape).astype(mx.float32)
return AttentionUtils.compute_attention(
query=query,
key=key,
value=value,
batch_size=self.batch_size,
num_heads=self.num_heads,
head_dim=self.head_dimension,
)