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vllm-omni/vllm_omni/engine/output_processor.py
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2026-04-21 11:51:39 +08:00

355 lines
15 KiB
Python

from typing import Any
import numpy as np
import torch
from vllm.logger import init_logger
from vllm.outputs import PoolingRequestOutput
from vllm.sampling_params import RequestOutputKind
from vllm.tokenizers import TokenizerLike
from vllm.v1.engine import EngineCoreOutput, EngineCoreRequest, FinishReason
from vllm.v1.engine.output_processor import OutputProcessor as VLLMOutputProcessor
from vllm.v1.engine.output_processor import (
OutputProcessorOutput,
RequestOutputCollector,
RequestState,
)
from vllm.v1.engine.parallel_sampling import ParentRequest
from vllm.v1.metrics.stats import IterationStats
from vllm_omni.outputs import OmniRequestOutput
logger = init_logger(__name__)
class OmniRequestState(RequestState):
"""Request state for omni models, tracking multimodal outputs.
Extends the base RequestState with support for accumulating
multimodal tensor outputs (e.g., images, audio, latents) that
are produced incrementally during generation.
"""
def __init__(
self,
*args,
**kwargs,
):
super().__init__(*args, **kwargs)
# Omni-specific: multimodal output accumulation
self.mm_type: str | None = None
self.mm_accumulated: dict[str, Any] | None = None
def add_multimodal_tensor(self, payload: Any | None, mm_type: str | None) -> None:
if payload is None:
return
try:
if mm_type:
self.mm_type = (mm_type or "").lower()
# Normalize incoming payload to dict on CPU
def _to_cpu(x):
if isinstance(x, torch.Tensor):
try:
return x.detach().to("cpu", non_blocking=True).contiguous()
except Exception:
return x
return x
if isinstance(payload, dict):
incoming: dict[str, Any] = {}
target_key = self.mm_type or "hidden"
for k, v in payload.items():
# Normalize producer keys to the modality name.
# AR runners produce {"hidden": ...} and generation
# runners produce {"model_outputs": ...}; remap both
# to the semantic modality key (e.g. "audio", "latent").
if k == "model_outputs":
k = target_key
elif k == "hidden" and target_key != "hidden":
k = target_key
if isinstance(v, dict):
incoming[k] = {str(sk): _to_cpu(sv) for sk, sv in v.items()}
else:
incoming[k] = _to_cpu(v)
else:
key = self.mm_type or "hidden"
incoming = {key: _to_cpu(payload)}
if self.mm_accumulated is None:
self.mm_accumulated = incoming
else:
# Merge keys; accumulate tensors in lists for deferred concatenation
for k, v in incoming.items():
if k not in self.mm_accumulated:
self.mm_accumulated[k] = v
else:
existing = self.mm_accumulated[k]
if isinstance(v, torch.Tensor) and isinstance(existing, torch.Tensor):
# Use list accumulation to avoid O(n²) repeated concatenation
self.mm_accumulated[k] = [existing, v]
elif isinstance(v, torch.Tensor) and isinstance(existing, list):
# Append to existing list
existing.append(v)
elif isinstance(v, dict) and isinstance(existing, dict):
# Merge nested dicts with list accumulation for tensors
for sk, sv in v.items():
if sk not in existing:
existing[sk] = sv
elif isinstance(sv, torch.Tensor) and isinstance(existing[sk], torch.Tensor):
existing[sk] = [existing[sk], sv]
elif isinstance(sv, torch.Tensor) and isinstance(existing[sk], list):
existing[sk].append(sv)
else:
existing[sk] = sv
else:
self.mm_accumulated[k] = v
except Exception:
# Log and continue without crashing the output pipeline
logger.exception("Error accumulating multimodal tensor")
def _consolidate_multimodal_tensors(self) -> None:
"""Consolidate accumulated tensor lists into single tensors via concatenation."""
if self.mm_accumulated is None:
return
try:
for k, v in self.mm_accumulated.items():
if isinstance(v, list) and v and isinstance(v[0], torch.Tensor):
try:
if k == "audio":
# When the audio tensor shape is inconsistent, torch.cat will fail.
# We need to use torch.cat in -1 dimension.
continue
elif k == "sr":
# Sample rate is a constant scalar, keep last value.
self.mm_accumulated[k] = v[-1]
else:
self.mm_accumulated[k] = torch.cat(v, dim=0)
except Exception:
# Keep last tensor on failure
logger.warning(f"Error concatenating tensor for key {k}; keeping last tensor")
self.mm_accumulated[k] = v[-1]
elif isinstance(v, dict):
for sk, sv in v.items():
if isinstance(sv, list) and sv and isinstance(sv[0], torch.Tensor):
try:
v[sk] = torch.cat(sv, dim=0)
except Exception:
v[sk] = sv[-1]
except Exception:
logger.exception("Error consolidating multimodal tensors")
# Override: do not route to pooling-only path; always create completion
# outputs, and attach pooling_result into the CompletionOutput.
def make_request_output(
self,
new_token_ids: list[int],
pooling_output: torch.Tensor | None,
finish_reason: FinishReason | None,
stop_reason: int | str | None,
kv_transfer_params: dict[str, Any] | None = None,
routed_experts: np.ndarray | None = None,
) -> OmniRequestOutput | PoolingRequestOutput | None:
"""Create a request output from generation results.
Creates a RequestOutput or PoolingRequestOutput from the generated
tokens and accumulated multimodal outputs. Attaches multimodal
tensors to the completion output if available.
Args:
new_token_ids: List of newly generated token IDs
pooling_output: Optional pooling output tensor
finish_reason: Optional finish reason indicating why generation stopped
stop_reason: Optional stop reason (token ID or stop string)
kv_transfer_params: Optional KV cache transfer parameters
Returns:
OmniRequestOutput or PoolingRequestOutput if output should be
emitted (based on finish status and output kind), None otherwise
"""
# Pooling-only requests should follow base behavior.
if self.detokenizer is None and pooling_output is not None:
return super().make_request_output(
new_token_ids,
pooling_output,
finish_reason,
stop_reason,
kv_transfer_params,
routed_experts,
)
finished = finish_reason is not None
final_only = self.output_kind == RequestOutputKind.FINAL_ONLY
if not finished and final_only:
return None
# Consolidate accumulated tensors when finishing.
if finished:
self._consolidate_multimodal_tensors()
if self.stream_interval > 1:
assert self.detokenizer is not None
# Send output request only when
# 1. It has finished, or
# 2. It is the first token, or
# 3. It has reached the stream interval number of tokens
if not (
finished
or self.sent_tokens_offset == 0
or self.detokenizer.num_output_tokens() - self.sent_tokens_offset >= self.stream_interval
):
return None
if self.output_kind == RequestOutputKind.DELTA:
# Send tokens from the offset in DELTA mode, otherwise all
# tokens are sent.
new_token_ids = self.detokenizer.output_token_ids[self.sent_tokens_offset :]
self.sent_tokens_offset = self.detokenizer.num_output_tokens()
external_req_id = self.external_req_id
output = self._new_completion_output(new_token_ids, finish_reason, stop_reason, routed_experts)
if self.parent_req is None:
outputs = [output]
else:
outputs, finished = self.parent_req.get_outputs(self.request_id, output)
if not outputs:
return None
external_req_id = self.parent_req.external_req_id
return self._new_request_output(external_req_id, outputs, finished, kv_transfer_params)
def _new_completion_output(
self,
token_ids: list[int],
finish_reason: FinishReason | None,
stop_reason: int | str | None,
routed_experts: np.ndarray | None = None,
) -> Any:
# Reuse base text/logprobs logic, then annotate with pooling_result.
base_output = super()._new_completion_output(token_ids, finish_reason, stop_reason, routed_experts)
try:
if not hasattr(base_output, "multimodal_output"):
setattr(base_output, "multimodal_output", {})
if self.mm_accumulated is not None:
mm_out = getattr(base_output, "multimodal_output")
if isinstance(mm_out, dict):
for k, v in self.mm_accumulated.items():
mm_out[k] = v
else:
setattr(base_output, "multimodal_output", self.mm_accumulated)
except Exception:
logger.exception("Error in _new_completion_output")
return base_output
class MultimodalOutputProcessor(VLLMOutputProcessor):
"""Handles multimodal output processing by capturing pooling_output
from EngineCoreOutput and accumulating it as multimodal tensors,
before delegating to the base vLLM OutputProcessor for text handling.
The actual data flow is:
1. For each EngineCoreOutput with pooling_output and a detokenizer:
- Capture pooling_output into OmniRequestState.add_multimodal_tensor()
- Clear eco.pooling_output to force text path in base processor
2. Base vLLM OutputProcessor handles text detokenization
3. On finish, _consolidate_multimodal_tensors() concatenates accumulated tensors
4. _new_completion_output() attaches mm_accumulated to CompletionOutput
"""
def __init__(
self,
tokenizer: TokenizerLike | None,
*,
log_stats: bool,
stream_interval: int = 1,
tracing_enabled: bool = False,
engine_core_output_type: str | None = None,
):
"""Initialize the multimodal output processor.
Args:
tokenizer: Tokenizer for detokenizing text outputs
log_stats: Whether to log statistics
stream_interval: Stream interval for output generation
engine_core_output_type: Optional output type specification
(e.g., "image", "audio", "latent"). Used to tag multimodal
outputs with the correct modality key.
"""
super().__init__(
tokenizer=tokenizer,
log_stats=log_stats,
stream_interval=stream_interval,
tracing_enabled=tracing_enabled,
)
self.engine_core_output_type = engine_core_output_type
def add_request(
self,
request: EngineCoreRequest,
prompt: str | None,
parent_req: ParentRequest | None = None,
request_index: int = 0,
queue: RequestOutputCollector | None = None,
) -> None:
"""Add a new request to be processed.
Creates an OmniRequestState for the request and registers it
for output processing.
Args:
request: Engine core request to add
prompt: Optional prompt string for the request
parent_req: Optional parent request for parallel sampling
request_index: Index of the request in the batch
queue: Optional queue for collecting outputs
Raises:
ValueError: If the request ID is already registered
"""
request_id = request.request_id
req_state = self.request_states.get(request_id)
if req_state is not None:
self._update_streaming_request_state(req_state, request, prompt)
return
req_state = OmniRequestState.from_new_request(
tokenizer=self.tokenizer,
request=request,
prompt=prompt,
parent_req=parent_req,
request_index=request_index,
queue=queue,
log_stats=self.log_stats,
stream_interval=self.stream_interval,
)
self.request_states[request_id] = req_state
if parent_req:
self.parent_requests[parent_req.request_id] = parent_req
self.external_req_ids[req_state.external_req_id].append(request_id)
def process_outputs(
self,
engine_core_outputs: list[EngineCoreOutput],
engine_core_timestamp: float | None = None,
iteration_stats: IterationStats | None = None,
) -> OutputProcessorOutput:
for eco in engine_core_outputs:
req_state = self.request_states.get(eco.request_id)
if req_state is None or not isinstance(req_state, OmniRequestState):
continue
if eco.pooling_output is not None and req_state.detokenizer is not None:
mm_type = (getattr(eco, "output_type", self.engine_core_output_type) or "").lower()
req_state.add_multimodal_tensor(eco.pooling_output, mm_type)
# Force text path in base processor for multimodal outputs.
eco.pooling_output = None
return super().process_outputs(
engine_core_outputs,
engine_core_timestamp=engine_core_timestamp,
iteration_stats=iteration_stats,
)