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enginex-biren-vllm/vllm/v1/attention/backends/short_conv_attn.py
2026-03-10 13:31:25 +08:00

95 lines
3.4 KiB
Python

# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
from dataclasses import dataclass
from typing import Optional
import torch
from vllm.attention.backends.abstract import AttentionBackend
from vllm.config import VllmConfig
from vllm.v1.attention.backends.utils import (AttentionMetadataBuilder,
CommonAttentionMetadata,
compute_causal_conv1d_metadata,
split_decodes_and_prefills)
from vllm.v1.kv_cache_interface import AttentionSpec, MambaSpec
class ShortConvAttentionBackend(AttentionBackend):
@staticmethod
def get_builder_cls() -> type["ShortConvAttentionMetadataBuilder"]:
return ShortConvAttentionMetadataBuilder
@dataclass
class ShortConvAttentionMetadata:
num_prefills: int
num_prefill_tokens: int
num_decodes: int
num_decode_tokens: int
query_start_loc: torch.Tensor
has_initial_states: torch.Tensor
state_indices_tensor: torch.Tensor # shape: [batch,]
# For causal_conv1d
nums_dict: Optional[dict] = None
batch_ptr: Optional[torch.Tensor] = None
token_chunk_offset_ptr: Optional[torch.Tensor] = None
class ShortConvAttentionMetadataBuilder(
AttentionMetadataBuilder[ShortConvAttentionMetadata]):
reorder_batch_threshold: int = 1
def __init__(self, kv_cache_spec: AttentionSpec, layer_names: list[str],
vllm_config: VllmConfig, device: torch.device):
super().__init__(kv_cache_spec, layer_names, vllm_config, device)
assert isinstance(kv_cache_spec, MambaSpec)
def build(self,
common_prefix_len: int,
common_attn_metadata: CommonAttentionMetadata,
fast_build: bool = False) -> ShortConvAttentionMetadata:
num_reqs = common_attn_metadata.num_reqs
query_start_loc = common_attn_metadata.query_start_loc
state_indices_tensor = common_attn_metadata.block_table_tensor[:, 0]
# for causal_conv1d
nums_dict, batch_ptr, token_chunk_offset_ptr = None, None, None
num_decodes, num_prefills, num_decode_tokens, num_prefill_tokens = (
split_decodes_and_prefills(
common_attn_metadata,
decode_threshold=self.reorder_batch_threshold))
has_initial_states = None
if num_prefills > 0:
#[batch,]
has_initial_states_cpu = (
common_attn_metadata.
num_computed_tokens_cpu[num_reqs - num_prefills:num_reqs] > 0)
has_initial_states = has_initial_states_cpu.to(
query_start_loc.device)
query_start_loc_p = common_attn_metadata.query_start_loc[
-num_prefills - 1:] - num_decode_tokens
nums_dict, batch_ptr, token_chunk_offset_ptr = \
compute_causal_conv1d_metadata(query_start_loc_p)
attn_metadata = ShortConvAttentionMetadata(
num_prefills=num_prefills,
num_prefill_tokens=num_prefill_tokens,
num_decodes=num_decodes,
num_decode_tokens=num_decode_tokens,
query_start_loc=query_start_loc,
has_initial_states=has_initial_states,
state_indices_tensor=state_indices_tensor,
nums_dict=nums_dict,
batch_ptr=batch_ptr,
token_chunk_offset_ptr=token_chunk_offset_ptr,
)
return attn_metadata