Wan2.1/shared/radial_attention/attn_mask.py
2025-09-27 15:22:31 +02:00

380 lines
17 KiB
Python

import torch
# import flashinfer
import matplotlib.pyplot as plt
# from sparse_sageattn import sparse_sageattn
from einops import rearrange, repeat
from sageattention import sageattn
from spas_sage_attn import block_sparse_sage2_attn_cuda
def get_cuda_arch_versions():
cuda_archs = []
for i in range(torch.cuda.device_count()):
major, minor = torch.cuda.get_device_capability(i)
cuda_archs.append(f"sm{major}{minor}")
return cuda_archs
from spas_sage_attn import block_sparse_sage2_attn_cuda
def sparge_mask_convert(mask: torch.Tensor, block_size: int = 128, arch="sm") -> torch.Tensor:
assert block_size in [128, 64], "Radial Attention only supports block size of 128 or 64"
assert mask.shape[0] == mask.shape[1], "Input mask must be square."
if block_size == 128:
if arch == "sm90":
new_mask = torch.repeat_interleave(mask, 2, dim=0)
else:
new_mask = torch.repeat_interleave(mask, 2, dim=1)
elif block_size == 64:
if arch == "sm90":
num_row, num_col = mask.shape
reshaped_mask = mask.view(num_row, num_col // 2, 2)
new_mask = torch.max(reshaped_mask, dim=2).values
else:
num_row, num_col = mask.shape
reshaped_mask = mask.view(num_row // 2, 2, num_col)
new_mask = torch.max(reshaped_mask, dim=1).values
return new_mask
def get_indptr_from_mask(mask, query):
# query shows the device of the indptr
# indptr (torch.Tensor) - the block index pointer of the block-sparse matrix on row dimension,
# shape `(MB + 1,)`, where `MB` is the number of blocks in the row dimension.
# The first element is always 0, and the last element is the number of blocks in the row dimension.
# The rest of the elements are the number of blocks in each row.
# the mask is already a block sparse mask
indptr = torch.zeros(mask.shape[0] + 1, device=query.device, dtype=torch.int32)
indptr[0] = 0
row_counts = mask.sum(dim=1).flatten() # Ensure 1D output [num_blocks_row]
indptr[1:] = torch.cumsum(row_counts, dim=0)
return indptr
def get_indices_from_mask(mask, query):
# indices (torch.Tensor) - the block indices of the block-sparse matrix on column dimension,
# shape `(nnz,),` where `nnz` is the number of non-zero blocks.
# The elements in `indices` array should be less than `NB`: the number of blocks in the column dimension.
nonzero_indices = torch.nonzero(mask)
indices = nonzero_indices[:, 1].to(dtype=torch.int32, device=query.device)
return indices
def shrinkMaskStrict(mask, block_size=128):
seqlen = mask.shape[0]
block_num = seqlen // block_size
mask = mask[:block_num * block_size, :block_num * block_size].view(block_num, block_size, block_num, block_size)
col_densities = mask.sum(dim = 1) / block_size
# we want the minimum non-zero column density in the block
non_zero_densities = col_densities > 0
high_density_cols = col_densities > 1/3
frac_high_density_cols = high_density_cols.sum(dim=-1) / (non_zero_densities.sum(dim=-1) + 1e-9)
block_mask = frac_high_density_cols > 0.6
block_mask[0:0] = True
block_mask[-1:-1] = True
return block_mask
def pad_qkv(input_tensor, block_size=128):
"""
Pad the input tensor to be a multiple of the block size.
input shape: (seqlen, num_heads, hidden_dim)
"""
seqlen, num_heads, hidden_dim = input_tensor.shape
# Calculate the necessary padding
padding_length = (block_size - (seqlen % block_size)) % block_size
# Create a padded tensor with zeros
padded_tensor = torch.zeros((seqlen + padding_length, num_heads, hidden_dim), device=input_tensor.device, dtype=input_tensor.dtype)
# Copy the original tensor into the padded tensor
padded_tensor[:seqlen, :, :] = input_tensor
return padded_tensor
def get_diagonal_split_mask(i, j, token_per_frame, sparse_type, query):
assert(sparse_type in ["radial"])
dist = abs(i - j)
group = dist.bit_length()
threshold = 128 # hardcoded threshold for now, which is equal to block-size
decay_length = 2 ** token_per_frame.bit_length() / 2 ** group
if decay_length >= threshold:
return torch.ones((token_per_frame, token_per_frame), device=query.device, dtype=torch.bool)
split_factor = int(threshold / decay_length)
modular = dist % split_factor
if modular == 0:
return torch.ones((token_per_frame, token_per_frame), device=query.device, dtype=torch.bool)
else:
return torch.zeros((token_per_frame, token_per_frame), device=query.device, dtype=torch.bool)
def get_window_width(i, j, token_per_frame, sparse_type, num_frame, decay_factor=1, block_size=128, model_type=None):
assert(sparse_type in ["radial"])
dist = abs(i - j)
if model_type == "wan":
if dist < 1:
return token_per_frame
if dist == 1:
return token_per_frame // 2
elif model_type == "hunyuan":
if dist <= 1:
return token_per_frame
else:
raise ValueError(f"Unknown model type: {model_type}")
group = dist.bit_length()
decay_length = 2 ** token_per_frame.bit_length() / 2 ** group * decay_factor
threshold = block_size
if decay_length >= threshold:
return decay_length
else:
return threshold
def gen_log_mask_shrinked(query, s, video_token_num, num_frame, block_size=128, sparse_type="log", decay_factor=0.5, model_type=None):
"""
A more memory friendly version, we generate the attention mask of each frame pair at a time,
shrinks it, and stores it into the final result
"""
final_log_mask = torch.zeros((s // block_size, s // block_size), device=query.device, dtype=torch.bool)
token_per_frame = video_token_num // num_frame
video_text_border = video_token_num // block_size
col_indices = torch.arange(0, token_per_frame, device=query.device).view(1, -1)
row_indices = torch.arange(0, token_per_frame, device=query.device).view(-1, 1)
final_log_mask[video_text_border:] = True
final_log_mask[:, video_text_border:] = True
for i in range(num_frame):
for j in range(num_frame):
local_mask = torch.zeros((token_per_frame, token_per_frame), device=query.device, dtype=torch.bool)
if j == 0 and model_type == "wan": # this is attention sink
local_mask = torch.ones((token_per_frame, token_per_frame), device=query.device, dtype=torch.bool)
else:
window_width = get_window_width(i, j, token_per_frame, sparse_type, num_frame, decay_factor=decay_factor, block_size=block_size, model_type=model_type)
local_mask = torch.abs(col_indices - row_indices) <= window_width
split_mask = get_diagonal_split_mask(i, j, token_per_frame, sparse_type, query)
local_mask = torch.logical_and(local_mask, split_mask)
remainder_row = (i * token_per_frame) % block_size
remainder_col = (j * token_per_frame) % block_size
# get the padded size
all_length_row = remainder_row + ((token_per_frame - 1) // block_size + 1) * block_size
all_length_col = remainder_col + ((token_per_frame - 1) // block_size + 1) * block_size
padded_local_mask = torch.zeros((all_length_row, all_length_col), device=query.device, dtype=torch.bool)
padded_local_mask[remainder_row:remainder_row + token_per_frame, remainder_col:remainder_col + token_per_frame] = local_mask
# shrink the mask
block_mask = shrinkMaskStrict(padded_local_mask, block_size=block_size)
# set the block mask to the final log mask
block_row_start = (i * token_per_frame) // block_size
block_col_start = (j * token_per_frame) // block_size
block_row_end = block_row_start + block_mask.shape[0]
block_col_end = block_col_start + block_mask.shape[1]
final_log_mask[block_row_start:block_row_end, block_col_start:block_col_end] = torch.logical_or(
final_log_mask[block_row_start:block_row_end, block_col_start:block_col_end], block_mask)
print(f"mask sparsity: {1 - final_log_mask.sum() / final_log_mask.numel()}")
return final_log_mask
class MaskMap:
_log_mask = None
def __init__(self, video_token_num=25440, num_frame=16):
self.video_token_num = video_token_num
self.num_frame = num_frame
def queryLogMask(self, query, sparse_type, block_size=128, decay_factor=0.5, model_type=None):
if MaskMap._log_mask is None:
MaskMap._log_mask = torch.ones((query.shape[0] // block_size, query.shape[0] // block_size), device=query.device, dtype=torch.bool)
MaskMap._log_mask = gen_log_mask_shrinked(query, query.shape[0], self.video_token_num, self.num_frame, sparse_type=sparse_type, decay_factor=decay_factor, model_type=model_type, block_size=block_size)
return MaskMap._log_mask
def SpargeSageAttnBackend(query, key, value, mask_map=None, video_mask=None, pre_defined_mask=None, block_size=128):
if video_mask.all():
# dense case
kv_border = pre_defined_mask[0].sum() if pre_defined_mask is not None else key.shape[0]
output_video = sageattn(
query[:mask_map.video_token_num, :, :].unsqueeze(0),
key[:kv_border, :, :].unsqueeze(0),
value[:kv_border, :, :].unsqueeze(0),
tensor_layout="NHD",
)[0]
if pre_defined_mask is not None:
output_text = flashinfer.single_prefill_with_kv_cache(
q=query[mask_map.video_token_num:, :, :],
k=key[:pre_defined_mask[0].sum(), :, :],
v=value[:pre_defined_mask[0].sum(), :, :],
causal=False,
return_lse=False,
)
return torch.cat([output_video, output_text], dim=0)
else:
return output_video
# sparse-sageattention only supports (b, h, s, d) layout, need rearrange first
query_hnd = rearrange(query.unsqueeze(0), "b s h d -> b h s d")
key_hnd = rearrange(key.unsqueeze(0), "b s h d -> b h s d")
value_hnd = rearrange(value.unsqueeze(0), "b s h d -> b h s d")
arch = get_cuda_arch_versions()[query.device.index]
converted_mask = repeat(sparge_mask_convert(mask=video_mask, block_size=block_size, arch=arch), "s t -> b h s t", b=query_hnd.shape[0], h=query_hnd.shape[1])
converted_mask = converted_mask.to(torch.int8)
if pre_defined_mask is None:
# wan case
output = block_sparse_sage2_attn_cuda(
query_hnd[:, :, :mask_map.video_token_num, :],
key_hnd[:, :, :mask_map.video_token_num, :],
value_hnd[:, :, :mask_map.video_token_num, :],
mask_id=converted_mask,
tensor_layout="HND",
)
# rearrange back to (s, h, d), we know that b = 1
output = rearrange(output, "b h s d -> s (b h) d", b=1)
return output
query_video = query_hnd[:, :, :mask_map.video_token_num, :]
key_video = key_hnd
value_video = value_hnd
kv_border = (pre_defined_mask[0].sum() + 63) // 64
converted_mask[:, :, :, kv_border:] = False
output_video = block_sparse_sage2_attn_cuda(
query_video,
key_video,
value_video,
mask_id=converted_mask[:, :, :mask_map.video_token_num // block_size, :].contiguous(),
tensor_layout="HND",
)
# rearrange back to (s, h, d), we know that b = 1
output_video = rearrange(output_video, "b h s d -> s (b h) d", b=1)
# gt = sparse_sageattn(
# query_video,
# key_video,
# value_video,
# mask_id=None,
# is_causal=False,
# tensor_layout="HND",
# )[0]
# import pdb; pdb.set_trace()
output_text = flashinfer.single_prefill_with_kv_cache(
q=query[mask_map.video_token_num:, :, :],
k=key[:pre_defined_mask[0].sum(), :, :],
v=value[:pre_defined_mask[0].sum(), :, :],
causal=False,
return_lse=False,
)
return torch.cat([output_video, output_text], dim=0)
def FlashInferBackend(query, key, value, mask_map=None, pre_defined_mask=None, bsr_wrapper=None):
if pre_defined_mask is not None:
video_video_o, video_video_o_lse = bsr_wrapper.run(
query[:mask_map.video_token_num, :, :],
key[:mask_map.video_token_num, :, :],
value[:mask_map.video_token_num, :, :],
return_lse=True
)
# perform non-causal flashinfer on the text tokens
video_text_o, video_text_o_lse = flashinfer.single_prefill_with_kv_cache(
q=query[:mask_map.video_token_num, :, :],
k=key[mask_map.video_token_num:, :, :],
v=value[mask_map.video_token_num:, :, :],
causal=False,
return_lse=True,
custom_mask=pre_defined_mask[:mask_map.video_token_num, mask_map.video_token_num:]
)
# merge the two results
o_video, _ = flashinfer.merge_state(v_a=video_video_o, s_a=video_video_o_lse, v_b=video_text_o, s_b=video_text_o_lse)
o_text = flashinfer.single_prefill_with_kv_cache(
q=query[mask_map.video_token_num:, :, :],
k=key,
v=value,
causal=False,
return_lse=False,
custom_mask=pre_defined_mask[mask_map.video_token_num:, :]
)
return torch.cat([o_video, o_text], dim=0)
else:
o = bsr_wrapper.run(
query[:mask_map.video_token_num, :, :],
key[:mask_map.video_token_num, :, :],
value[:mask_map.video_token_num, :, :]
)
return o
def RadialAttention(query, key, value, mask_map=None, sparsity_type="radial", block_size=128, decay_factor=1, model_type=None, pre_defined_mask=None, use_sage_attention=False):
orig_seqlen, num_head, hidden_dim = query.shape
if sparsity_type == "dense":
video_mask = torch.ones((mask_map.video_token_num // block_size, mask_map.video_token_num // block_size), device=query.device, dtype=torch.bool)
else:
video_mask = mask_map.queryLogMask(query, sparsity_type, block_size=block_size, decay_factor=decay_factor, model_type=model_type) if mask_map else None
backend = "sparse_sageattn" if use_sage_attention else "flashinfer"
if backend == "flashinfer":
video_mask = video_mask[:mask_map.video_token_num // block_size, :mask_map.video_token_num // block_size]
# perform block-sparse attention on the video tokens
workspace_buffer = torch.empty(128 * 1024 * 1024, device=query.device, dtype=torch.uint8)
bsr_wrapper = flashinfer.BlockSparseAttentionWrapper(
workspace_buffer,
backend="fa2",
)
indptr = get_indptr_from_mask(video_mask, query)
indices = get_indices_from_mask(video_mask, query)
bsr_wrapper.plan(
indptr=indptr,
indices=indices,
M=mask_map.video_token_num,
N=mask_map.video_token_num,
R=block_size,
C=block_size,
num_qo_heads=num_head,
num_kv_heads=num_head,
head_dim=hidden_dim,
q_data_type=query.dtype,
kv_data_type=key.dtype,
o_data_type=query.dtype,
)
return FlashInferBackend(query, key, value, mask_map, pre_defined_mask, bsr_wrapper)
elif backend == "sparse_sageattn":
return SpargeSageAttnBackend(query, key, value, mask_map, video_mask, pre_defined_mask, block_size=block_size)
if __name__ == "__main__":
query = torch.randn(1, 2, 4, 64).cuda()
# mask = torch.tensor([
# [True, False, True, False],
# [False, True, False, True],
# [True, False, False, True],
# [False, True, True, False]
# ], dtype=torch.bool)
# indices = get_indices_from_mask(mask, query)
# indptr = get_indptr_from_mask(mask, query)
# print("Indices: ", indices)
# print("Indptr: ", indptr)
video_token_num = 3840 * 30
num_frame = 30
token_per_frame = video_token_num / num_frame
padded_video_token_num = ((video_token_num + 1) // 128 + 1) * 128
print("padded: ", padded_video_token_num)
temporal_mask = gen_log_mask_shrinked(query, padded_video_token_num, video_token_num, num_frame, sparse_type="radial", decay_factor=1, model_type="hunyuan")
plt.figure(figsize=(10, 8), dpi=500)
plt.imshow(temporal_mask.cpu().numpy()[:, :], cmap='hot')
plt.colorbar()
plt.title("Temporal Mask")
plt.savefig("temporal_mask.png",
dpi=300,
bbox_inches='tight',
pad_inches=0.1)
plt.close()
# save the mask tensor
torch.save(temporal_mask, "temporal_mask.pt")