Files
enginex-mthreads-vllm/vllm/worker/cpu_model_runner.py
2026-01-09 13:34:11 +08:00

347 lines
14 KiB
Python

from typing import List, Optional, Tuple
import torch
from torch import nn
from vllm.attention import AttentionMetadata, get_attn_backend
from vllm.config import (DeviceConfig, LoadConfig, LoRAConfig, ModelConfig,
ParallelConfig, SchedulerConfig, VisionLanguageConfig)
from vllm.distributed import broadcast_tensor_dict
from vllm.logger import init_logger
from vllm.model_executor import SamplingMetadata
from vllm.model_executor.model_loader import get_model
from vllm.sequence import SamplerOutput, SequenceGroupMetadata
from vllm.utils import make_tensor_with_pad
logger = init_logger(__name__)
_PAD_SLOT_ID = -1
class CPUModelRunner:
def __init__(
self,
model_config: ModelConfig,
parallel_config: ParallelConfig,
scheduler_config: SchedulerConfig,
device_config: DeviceConfig,
load_config: LoadConfig,
lora_config: Optional[LoRAConfig],
vision_language_config: Optional[VisionLanguageConfig],
kv_cache_dtype: Optional[str] = "auto",
is_driver_worker: bool = False,
*args,
**kwargs,
):
self.model_config = model_config
self.parallel_config = parallel_config
self.scheduler_config = scheduler_config
# Currently, CPU worker doesn't support chunked prefill.
assert self.scheduler_config.chunked_prefill_enabled is False
self.lora_config = lora_config
self.vision_language_config = vision_language_config
self.load_config = load_config
self.is_driver_worker = is_driver_worker
# model_config can be None in tests/samplers/test_sampler.py.
# FIXME(woosuk): This is a hack to make the tests work. Refactor this.
self.sliding_window = (model_config.get_sliding_window()
if model_config is not None else None)
self.device_config = (device_config
if device_config is not None else DeviceConfig())
self.device = self.device_config.device
self.kv_cache_dtype = kv_cache_dtype
self.attn_backend = get_attn_backend(
self.model_config.dtype if model_config is not None else None)
# Lazy initialization.
self.model: nn.Module # Set after init_Model
self.block_size: int # Set after initial profiling.
def load_model(self) -> None:
self.model = get_model(
model_config=self.model_config,
load_config=self.load_config,
device_config=self.device_config,
vision_language_config=self.vision_language_config,
lora_config=self.lora_config,
parallel_config=self.parallel_config,
scheduler_config=self.scheduler_config)
def _prepare_prompt(
self,
seq_group_metadata_list: List[SequenceGroupMetadata],
) -> Tuple[torch.Tensor, torch.Tensor, AttentionMetadata, List[int],
Optional[torch.Tensor]]:
assert len(seq_group_metadata_list) > 0
input_tokens: List[int] = []
input_positions: List[int] = []
slot_mapping: List[int] = []
seq_lens: List[int] = []
multi_modal_input_list: List[torch.Tensor] = []
for seq_group_metadata in seq_group_metadata_list:
assert seq_group_metadata.is_prompt
seq_ids = list(seq_group_metadata.seq_data.keys())
assert len(seq_ids) == 1
seq_id = seq_ids[0]
seq_data = seq_group_metadata.seq_data[seq_id]
prompt_tokens = seq_data.get_token_ids()
computed_len = seq_data.get_num_computed_tokens()
seq_len = len(prompt_tokens)
seq_lens.append(seq_len) # Prompt token num
input_tokens.extend(prompt_tokens) # Token ids
# Token position ids
# NOTE(woosuk): Here we assume that the first token in the prompt
# is always the first token in the sequence.
input_positions.extend(list(range(computed_len, seq_len)))
if seq_group_metadata.multi_modal_data:
multi_modal_input_list.append(
seq_group_metadata.multi_modal_data.data)
# Compute the slot mapping.
block_table = seq_group_metadata.block_tables[seq_id]
# Mask the [0, start_idx) tokens of the prompt with _PAD_SLOT_ID,
# where start_idx is max(0, seq_len - sliding_window).
# For example, if the prompt len is 10, sliding window is 8, and
# block size is 4, the first two tokens are masked and the slot
# mapping will be [-1, -1, 2, 3, 4, 5, 6, 7, 0, 1].
start_idx = 0
if self.sliding_window is not None:
start_idx = max(0, seq_len - self.sliding_window)
for i in range(computed_len, seq_len):
if i < start_idx:
slot_mapping.append(_PAD_SLOT_ID)
continue
block_number = block_table[i //
self.block_size] # type: ignore
block_offset = i % self.block_size # type: ignore
slot = block_number * self.block_size + block_offset
slot_mapping.append(slot)
if multi_modal_input_list:
assert self.vision_language_config, (
"Multi-modal inputs are only supported by "
"vision language models.")
multi_modal_input = torch.cat(multi_modal_input_list,
dim=0).to(self.device)
else:
multi_modal_input = None
num_prompt_tokens = len(input_tokens)
input_tokens = torch.tensor(input_tokens,
dtype=torch.long,
device=self.device) # type: ignore
input_positions = torch.tensor(input_positions,
dtype=torch.long,
device=self.device) # type: ignore
slot_mapping = torch.tensor(slot_mapping,
dtype=torch.long,
device=self.device) # type: ignore
attn_metadata = self.attn_backend.make_metadata(
is_prompt=True,
seq_lens=seq_lens,
seq_lens_tensor=None,
max_seq_len=None,
num_prefills=len(seq_lens),
num_prefill_tokens=num_prompt_tokens,
num_decode_tokens=0,
prefill_metadata=None,
decode_metadata=None,
block_tables=torch.tensor([]),
slot_mapping=slot_mapping,
kv_cache_dtype=self.kv_cache_dtype,
)
return (input_tokens, input_positions, attn_metadata, seq_lens,
multi_modal_input)
def _prepare_decode(
self,
seq_group_metadata_list: List[SequenceGroupMetadata],
) -> Tuple[torch.Tensor, torch.Tensor, AttentionMetadata]:
assert len(seq_group_metadata_list) > 0
input_tokens: List[int] = []
input_positions: List[int] = []
slot_mapping: List[int] = []
seq_lens: List[int] = []
block_tables: List[List[int]] = []
for seq_group_metadata in seq_group_metadata_list:
assert not seq_group_metadata.is_prompt
assert seq_group_metadata.token_chunk_size == 1
seq_ids = list(seq_group_metadata.seq_data.keys())
for seq_id in seq_ids:
seq_data = seq_group_metadata.seq_data[seq_id]
generation_token = seq_data.get_last_token_id()
input_tokens.append(generation_token)
seq_len = seq_data.get_len()
position = seq_len - 1
input_positions.append(position)
seq_len = seq_len if self.sliding_window is None else min(
seq_len, self.sliding_window)
seq_lens.append(seq_len)
block_table = seq_group_metadata.block_tables[seq_id]
block_number = block_table[position // self.block_size]
block_offset = position % self.block_size
slot = block_number * self.block_size + block_offset
slot_mapping.append(slot)
if self.sliding_window is not None:
sliding_window_blocks = (self.sliding_window //
self.block_size)
block_table = block_table[-sliding_window_blocks:]
block_tables.append(block_table)
max_seq_len = max(seq_lens)
input_tokens = torch.tensor(input_tokens,
dtype=torch.long,
device=self.device)
input_positions = torch.tensor(input_positions,
dtype=torch.long,
device=self.device)
slot_mapping = torch.tensor(slot_mapping,
dtype=torch.long,
device=self.device)
seq_lens_tensor = torch.tensor(seq_lens,
dtype=torch.int,
device=self.device)
max_block_table_len = max(
len(block_table) for block_table in block_tables)
block_tables = make_tensor_with_pad(
block_tables,
max_len=max_block_table_len,
pad=0,
dtype=torch.int,
device=self.device,
)
attn_metadata = self.attn_backend.make_metadata(
is_prompt=False,
slot_mapping=slot_mapping,
seq_lens=seq_lens,
seq_lens_tensor=seq_lens_tensor,
max_seq_len=max_seq_len,
num_prefill_tokens=0,
num_decode_tokens=len(input_tokens),
num_prefills=0,
prefill_metadata=None,
decode_metadata=None,
block_tables=block_tables,
kv_cache_dtype=self.kv_cache_dtype,
)
return (
input_tokens,
input_positions,
attn_metadata,
)
def prepare_input_tensors(
self,
seq_group_metadata_list: List[SequenceGroupMetadata],
) -> Tuple[torch.Tensor, torch.Tensor, AttentionMetadata, SamplingMetadata,
Optional[torch.Tensor]]:
multi_modal_input = None
if self.is_driver_worker:
# NOTE: We assume that all sequences in the group are all prompts or
# all decodes.
is_prompt = seq_group_metadata_list[0].is_prompt
# Prepare input tensors.
if is_prompt:
(input_tokens, input_positions, attn_metadata, seq_lens,
multi_modal_input
) = self._prepare_prompt(seq_group_metadata_list)
else:
(input_tokens, input_positions,
attn_metadata) = self._prepare_decode(seq_group_metadata_list)
seq_lens = []
sampling_metadata = SamplingMetadata.prepare(
seq_group_metadata_list,
seq_lens,
# query_lens is not needed if chunked prefill is not
# supported. Since CPU worker doesn't support chunked prefill
# just use seq_lens instead.
seq_lens,
self.device,
pin_memory=False)
# Broadcast the metadata.
metadata_dict = {
"input_tokens": input_tokens,
"input_positions": input_positions,
"selected_token_indices":
sampling_metadata.selected_token_indices,
}
metadata_dict.update(attn_metadata.asdict_zerocopy())
broadcast_tensor_dict(metadata_dict, src=0)
else:
metadata_dict = broadcast_tensor_dict(src=0)
input_tokens = metadata_dict.pop("input_tokens")
input_positions = metadata_dict.pop("input_positions")
selected_token_indices = metadata_dict.pop(
"selected_token_indices")
attn_metadata = self.attn_backend.make_metadata(**metadata_dict)
sampling_metadata = SamplingMetadata(
seq_groups=None,
seq_data=None,
seq_lens=None,
selected_token_indices=selected_token_indices,
categorized_sample_indices=None,
generators=None,
)
return (input_tokens, input_positions, attn_metadata,
sampling_metadata, multi_modal_input)
@torch.inference_mode()
def execute_model(
self,
seq_group_metadata_list: List[SequenceGroupMetadata],
kv_caches: List[torch.Tensor],
) -> Optional[SamplerOutput]:
(input_tokens, input_positions, attn_metadata, sampling_metadata,
multi_modal_input
) = self.prepare_input_tensors(seq_group_metadata_list)
model_executable = self.model
execute_model_kwargs = {
"input_ids": input_tokens,
"positions": input_positions,
"kv_caches": kv_caches,
"attn_metadata": attn_metadata,
}
if self.vision_language_config:
execute_model_kwargs.update({"image_input": multi_modal_input})
hidden_states = model_executable(**execute_model_kwargs)
# Compute the logits.
logits = self.model.compute_logits(hidden_states, sampling_metadata)
# Only perform sampling in the driver worker.
if not self.is_driver_worker:
return None
# Sample the next token.
output = self.model.sample(
logits=logits,
sampling_metadata=sampling_metadata,
)
return output