Files
agentic-kvc/third_party/vllm/vllm/model_executor/models/colmodernvbert.py
Gahow Wang 445e491123 Add vLLM v0.18.1 source tree with KV transfer abort fix
third_party/vllm/ now tracked in git for direct patch management.
Based on vLLM v0.18.1 release with one patch applied:

  vllm/v1/core/sched/scheduler.py:
    Replace fatal assert with graceful skip when KV transfer callback
    arrives for an already-aborted request during PD disaggregated serving.

Future vLLM modifications should be made directly in third_party/vllm/
and committed normally. The patches/ directory is kept as documentation
of what changed from upstream.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-05-22 00:30:38 +08:00

435 lines
16 KiB
Python

# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
"""ColModernVBERT: multimodal late-interaction retrieval model.
Combines SigLIP vision encoder + ModernBERT text encoder with a pixel
shuffle connector and ColBERT-style 128-dim per-token embeddings.
Reference: https://huggingface.co/ModernVBERT/colmodernvbert-merged
"""
from collections.abc import Iterable, Mapping, Sequence
import torch
from torch import nn
from transformers import BatchFeature
from vllm.config import VllmConfig
from vllm.config.multimodal import BaseDummyOptions
from vllm.model_executor.layers.pooler.tokwise import pooler_for_token_embed
from vllm.model_executor.model_loader.weight_utils import default_weight_loader
from vllm.multimodal import MULTIMODAL_REGISTRY
from vllm.multimodal.inputs import (
MultiModalDataDict,
MultiModalFieldConfig,
MultiModalKwargsItems,
)
from vllm.multimodal.parse import ImageSize, MultiModalDataItems
from vllm.multimodal.processing import (
BaseDummyInputsBuilder,
BaseMultiModalProcessor,
BaseProcessingInfo,
PromptIndexTargets,
PromptReplacement,
PromptUpdate,
)
from vllm.sequence import IntermediateTensors
from vllm.transformers_utils.configs.colmodernvbert import ColModernVBertConfig
from .interfaces import (
MultiModalEmbeddings,
SupportsLateInteraction,
SupportsMultiModal,
)
from .interfaces_base import default_pooling_type
from .modernbert import ModernBertEmbeddings, ModernBertLayer
from .siglip import SiglipVisionModel
from .utils import AutoWeightsLoader, WeightsMapper, maybe_prefix
# ---------------------------------------------------------------------------
# Connector: pixel shuffle + simple linear projection
# ---------------------------------------------------------------------------
class ColModernVBertConnector(nn.Module):
"""Pixel shuffle spatial reduction followed by a linear projection.
Reduces the vision encoder's token count by ``factor^2`` via pixel-shuffle
spatial rearrangement, then projects the concatenated channels to the text
encoder's hidden size with a single bias-free linear layer.
"""
def __init__(self, config: ColModernVBertConfig):
super().__init__()
self.pixel_shuffle_factor = config.pixel_shuffle_factor
vision_hidden_size = config.vision_config.hidden_size
input_size = vision_hidden_size * (self.pixel_shuffle_factor**2)
output_size = config.hidden_size
self.proj = nn.Linear(input_size, output_size, bias=False)
def pixel_shuffle(self, features: torch.Tensor) -> torch.Tensor:
"""Spatial rearrangement that reduces seq length by factor^2."""
batch_size, seq_length, hidden_size = features.shape
height = width = int(seq_length**0.5)
factor = self.pixel_shuffle_factor
# Reshape to (B, H, W, C)
features = features.view(batch_size, height, width, hidden_size)
# Reshape to (B, H/f, f, W/f, f, C)
features = features.view(
batch_size, height // factor, factor, width // factor, factor, hidden_size
)
# Permute to (B, H/f, W/f, f, f, C)
features = features.permute(0, 1, 3, 2, 4, 5)
# Reshape to (B, H/f, W/f, C * f^2)
new_hidden_size = hidden_size * (factor**2)
features = features.reshape(
batch_size, height // factor, width // factor, new_hidden_size
)
return features
def forward(self, features: torch.Tensor) -> torch.Tensor:
features = self.pixel_shuffle(features)
batch_size = features.shape[0]
features = features.reshape(batch_size, -1, features.shape[-1])
return self.proj(features)
# ---------------------------------------------------------------------------
# Multimodal processing
# ---------------------------------------------------------------------------
class ColModernVBertProcessingInfo(BaseProcessingInfo):
def get_hf_config(self) -> ColModernVBertConfig:
return self.ctx.get_hf_config(ColModernVBertConfig)
def get_supported_mm_limits(self) -> Mapping[str, int | None]:
return {"image": None}
def get_image_size_with_most_features(self) -> ImageSize:
config = self.get_hf_config()
size = config.vision_config.image_size
return ImageSize(width=size, height=size)
def get_num_image_tokens(
self,
*,
image_width: int,
image_height: int,
) -> int:
return self.get_hf_config().image_seq_len
class ColModernVBertDummyInputsBuilder(
BaseDummyInputsBuilder[ColModernVBertProcessingInfo],
):
def get_dummy_text(self, mm_counts: Mapping[str, int]) -> str:
return ""
def get_dummy_mm_data(
self,
seq_len: int,
mm_counts: Mapping[str, int],
mm_options: Mapping[str, BaseDummyOptions],
) -> MultiModalDataDict:
num_images = mm_counts.get("image", 0)
target_width, target_height = self.info.get_image_size_with_most_features()
image_overrides = mm_options.get("image")
return {
"image": self._get_dummy_images(
width=target_width,
height=target_height,
num_images=num_images,
overrides=image_overrides,
)
}
class ColModernVBertMultiModalProcessor(
BaseMultiModalProcessor[ColModernVBertProcessingInfo],
):
def _call_hf_processor(
self,
prompt: str,
mm_data: Mapping[str, object],
mm_kwargs: Mapping[str, object],
tok_kwargs: Mapping[str, object],
) -> BatchFeature:
tokenizer = self.info.get_tokenizer()
text_encoding = tokenizer(
prompt,
return_tensors="pt",
**tok_kwargs,
)
result = BatchFeature(data=dict(text_encoding))
images = mm_data.get("images")
if images:
from transformers import Idefics3ImageProcessor
image_processor = Idefics3ImageProcessor.from_pretrained(
self.info.ctx.model_config.model,
revision=self.info.ctx.model_config.revision,
)
image_outputs = image_processor(
images=images,
do_image_splitting=False,
return_tensors="pt",
)
result.update(image_outputs)
return result
def _hf_processor_applies_updates(
self,
prompt_text: str,
mm_items: MultiModalDataItems,
hf_processor_mm_kwargs: Mapping[str, object],
tokenization_kwargs: Mapping[str, object],
) -> bool:
return False
def _get_mm_fields_config(
self,
hf_inputs: BatchFeature,
hf_processor_mm_kwargs: Mapping[str, object],
) -> Mapping[str, MultiModalFieldConfig]:
return dict(
pixel_values=MultiModalFieldConfig.batched("image"),
)
def _get_prompt_updates(
self,
mm_items: MultiModalDataItems,
hf_processor_mm_kwargs: Mapping[str, object],
out_mm_kwargs: MultiModalKwargsItems,
) -> Sequence[PromptUpdate]:
config = self.info.get_hf_config()
image_token_id = config.image_token_id
num_tokens = config.image_seq_len
def get_replacement(item_idx: int):
return [image_token_id] * num_tokens
return [
PromptReplacement(
modality="image",
target=PromptIndexTargets.start(),
replacement=get_replacement,
),
]
# ---------------------------------------------------------------------------
# Model
# ---------------------------------------------------------------------------
@MULTIMODAL_REGISTRY.register_processor(
ColModernVBertMultiModalProcessor,
info=ColModernVBertProcessingInfo,
dummy_inputs=ColModernVBertDummyInputsBuilder,
)
@default_pooling_type(seq_pooling_type="CLS", tok_pooling_type="ALL")
class ColModernVBertForRetrieval(
nn.Module, SupportsMultiModal, SupportsLateInteraction
):
"""ColModernVBERT multimodal late-interaction retrieval model.
Architecture:
Image -> SiglipVisionModel -> ColModernVBertConnector
Text -> ModernBertEmbeddings → [merge] → ModernBertLayers → norm
custom_text_proj → L2 norm
per-token 128-d embeddings
"""
is_pooling_model = True
def __init__(self, *, vllm_config: VllmConfig, prefix: str = ""):
super().__init__()
config: ColModernVBertConfig = vllm_config.model_config.hf_config
self.config = config
text_config = config.text_config
quant_config = vllm_config.quant_config
# --- Vision encoder (reuses SiglipVisionModel from siglip.py) ---
self.vision_model = SiglipVisionModel(
config.vision_config,
quant_config,
prefix=maybe_prefix(prefix, "vision_model"),
)
# --- Connector (pixel shuffle + linear projection) ---
self.connector = ColModernVBertConnector(config)
# --- Text encoder (built from ModernBERT components directly) ---
# We build the components individually rather than wrapping
# ``ModernBertModel`` because ``ModernBertEncoderLayer`` reads
# ``vllm_config.model_config.hf_config`` which would be
# ``ColModernVBertConfig``, not ``ModernBertConfig``.
self.text_embeddings = ModernBertEmbeddings(text_config)
self.text_layers = nn.ModuleList(
[
ModernBertLayer(
config=text_config,
layer_id=i,
prefix=f"{prefix}.text_layers.{i}",
)
for i in range(text_config.num_hidden_layers)
]
)
self.text_final_norm = nn.LayerNorm(
text_config.hidden_size,
eps=text_config.norm_eps,
bias=text_config.norm_bias,
)
# --- ColBERT projection (768 -> 128, with bias) ---
self.custom_text_proj = nn.Linear(
text_config.hidden_size,
config.embedding_dim,
bias=True,
dtype=vllm_config.model_config.head_dtype,
)
# --- Pooler (applies projection + L2 normalize) ---
pooler_config = vllm_config.model_config.pooler_config
assert pooler_config is not None
self.pooler = pooler_for_token_embed(
pooler_config,
projector=self.custom_text_proj,
)
# ---- multimodal ---------------------------------------------------------
def _get_image_features(
self,
pixel_values: torch.Tensor,
) -> torch.Tensor:
# Idefics3ImageProcessor may return (batch, tiles, C, H, W);
# flatten to (batch*tiles, C, H, W) for SiglipVisionModel.
if pixel_values.dim() == 5:
b, t, c, h, w = pixel_values.shape
pixel_values = pixel_values.reshape(b * t, c, h, w)
vision_outputs = self.vision_model(
pixel_values.to(dtype=self.vision_model.dtype),
)
return self.connector(vision_outputs)
def embed_multimodal(self, **kwargs: object) -> MultiModalEmbeddings:
pixel_values = kwargs.pop("pixel_values", None)
if pixel_values is None:
return []
assert isinstance(pixel_values, torch.Tensor)
image_features = self._get_image_features(pixel_values)
return list(image_features)
# ---- forward ------------------------------------------------------------
def forward(
self,
input_ids: torch.Tensor,
positions: torch.Tensor,
intermediate_tensors: IntermediateTensors | None = None,
inputs_embeds: torch.Tensor | None = None,
) -> torch.Tensor:
hidden_states = self.text_embeddings(input_ids, inputs_embeds=inputs_embeds)
for layer in self.text_layers:
hidden_states = layer(hidden_states, positions)
return self.text_final_norm(hidden_states)
# ---- weight loading -----------------------------------------------------
# Checkpoint prefix → vLLM param prefix.
# More-specific prefixes must appear before shorter ones.
hf_to_vllm_mapper = WeightsMapper(
orig_to_new_prefix={
"model.text_model.layers.": "text_layers.",
"model.text_model.embeddings.": "text_embeddings.",
"model.text_model.final_norm.": "text_final_norm.",
"model.connector.modality_projection.": "connector.",
"model.custom_text_proj.": "custom_text_proj.",
"model.vision_model.": "vision_model.vision_model.",
"model.": "",
},
)
# Checkpoint names for DecoupledEmbedding parts
_BASE_EMB = "model.text_model.embeddings.tok_embeddings.weight"
_EXTRA_EMB = (
"model.text_model.embeddings.tok_embeddings.additional_embedding.weight"
)
def load_weights(
self,
weights: Iterable[tuple[str, torch.Tensor]],
) -> set[str]:
# DecoupledEmbedding requires concatenating base + additional
# embedding tensors before loading, so we extract them first.
base_embedding_weight: torch.Tensor | None = None
additional_embedding_weight: torch.Tensor | None = None
remaining: list[tuple[str, torch.Tensor]] = []
for name, tensor in weights:
if name == self._BASE_EMB:
base_embedding_weight = tensor
elif name == self._EXTRA_EMB:
additional_embedding_weight = tensor
else:
remaining.append((name, tensor))
# Load all non-embedding weights via AutoWeightsLoader
loader = AutoWeightsLoader(self)
loaded_params = loader.load_weights(
remaining,
mapper=self.hf_to_vllm_mapper,
)
# Concatenate and load DecoupledEmbedding weights
if base_embedding_weight is not None:
combined = base_embedding_weight
if additional_embedding_weight is not None:
combined = torch.cat(
[base_embedding_weight, additional_embedding_weight],
dim=0,
)
param_name = "text_embeddings.tok_embeddings.weight"
params_dict = dict(self.named_parameters())
if param_name in params_dict:
param = params_dict[param_name]
weight_loader = getattr(
param,
"weight_loader",
default_weight_loader,
)
weight_loader(param, combined)
loaded_params.add(param_name)
elif additional_embedding_weight is not None:
raise ValueError(
"Found 'text_model.embeddings.tok_embeddings"
".additional_embedding.weight' but not "
"'text_model.embeddings.tok_embeddings.weight'"
)
# The pooler wraps ``custom_text_proj`` as its head projector.
# Mark those params as loaded under the pooler path too.
if hasattr(self, "pooler") and hasattr(self.pooler, "head"):
head = self.pooler.head
projector = getattr(head, "projector", None)
if projector is not None and isinstance(projector, nn.Module):
for pname, _ in projector.named_parameters():
loaded_params.add(f"pooler.head.projector.{pname}")
return loaded_params