[Model] Move `multimodal_cpu_fields` definition to field config (#30181)

Signed-off-by: DarkLight1337 <tlleungac@connect.ust.hk>

tests/distributed/test_shm_storage.py

@@ -28,7 +28,7 @@ def _dummy_elem(modality: str, key: str, size: int):
         modality=modality,
         key=key,
         data=torch.empty((size,), dtype=torch.int8),
-        field=MultiModalSharedField(1),
+        field=MultiModalSharedField(batch_size=1),
     )
 
 

tests/multimodal/test_cache.py

@@ -51,7 +51,7 @@ def _dummy_elem(
         modality=modality,
         key=key,
         data=data,
-        field=MultiModalSharedField(1),
+        field=MultiModalSharedField(batch_size=1),
     )
 
 

tests/v1/test_serial_utils.py

@@ -104,22 +104,31 @@ class MyRequest(msgspec.Struct):
 
 def test_multimodal_kwargs():
     e1 = MultiModalFieldElem(
-        "audio", "a0", torch.zeros(1000, dtype=torch.bfloat16), MultiModalBatchedField()
+        "audio",
+        "a0",
+        torch.zeros(1000, dtype=torch.bfloat16),
+        MultiModalBatchedField(),
     )
     e2 = MultiModalFieldElem(
         "video",
         "v0",
         [torch.zeros(1000, dtype=torch.int8) for _ in range(4)],
-        MultiModalFlatField([[slice(1, 2, 3), slice(4, 5, 6)], [slice(None, 2)]], 0),
+        MultiModalFlatField(
+            slices=[[slice(1, 2, 3), slice(4, 5, 6)], [slice(None, 2)]],
+            dim=0,
+        ),
     )
     e3 = MultiModalFieldElem(
-        "image", "i0", torch.zeros(1000, dtype=torch.int32), MultiModalSharedField(4)
+        "image",
+        "i0",
+        torch.zeros(1000, dtype=torch.int32),
+        MultiModalSharedField(batch_size=4),
     )
     e4 = MultiModalFieldElem(
         "image",
         "i1",
         torch.zeros(1000, dtype=torch.int32),
-        MultiModalFlatField([slice(1, 2, 3), slice(4, 5, 6)], 2),
+        MultiModalFlatField(slices=[slice(1, 2, 3), slice(4, 5, 6)], dim=2),
     )
     audio = MultiModalKwargsItem.from_elems([e1])
     video = MultiModalKwargsItem.from_elems([e2])
@@ -138,8 +147,8 @@ def test_multimodal_kwargs():
 
     total_len = sum(memoryview(x).cast("B").nbytes for x in encoded)
 
-    # expected total encoding length, should be 14306, +-20 for minor changes
-    assert 14275 <= total_len <= 14325
+    # expected total encoding length, should be 14395, +-20 for minor changes
+    assert 14375 <= total_len <= 14425
     decoded = decoder.decode(encoded).mm[0]
     assert isinstance(decoded, MultiModalKwargsItems)
 

vllm/model_executor/models/glm4_1v.py

@@ -787,10 +787,10 @@ class Glm4vVisionTransformer(nn.Module):
     def forward(
         self,
         x: torch.Tensor,
-        grid_thw: list[list[int]],
+        grid_thw: torch.Tensor | list[list[int]],
     ) -> torch.Tensor:
-        # Convert grid_thw to tensor (always expecting list format now)
-        grid_thw = torch.tensor(grid_thw, device=x.device, dtype=torch.long)
+        if isinstance(grid_thw, list):
+            grid_thw = torch.tensor(grid_thw, dtype=torch.int32)
 
         # patchify
         x = x.to(device=self.device, dtype=self.dtype)
@@ -805,7 +805,8 @@ class Glm4vVisionTransformer(nn.Module):
         cu_seqlens = torch.repeat_interleave(
             grid_thw[:, 1] * grid_thw[:, 2], grid_thw[:, 0]
         ).cumsum(dim=0, dtype=torch.int32)
-        cu_seqlens = F.pad(cu_seqlens, (1, 0), "constant", 0)
+        cu_seqlens = torch.cat([cu_seqlens.new_zeros(1), cu_seqlens])
+        cu_seqlens = cu_seqlens.to(self.device, non_blocking=True)
 
         # pre-compute max_seqlen for attn mask to reduce cuMemcpy operations
         max_seqlen = self.compute_attn_mask_seqlen(cu_seqlens)
@@ -1548,7 +1549,6 @@ class Glm4vForConditionalGeneration(
     ) -> tuple[torch.Tensor, ...]:
         grid_thw = image_input["image_grid_thw"]
         assert grid_thw.ndim == 2
-        grid_thw_list = grid_thw.tolist()
 
         if image_input["type"] == "image_embeds":
             image_embeds = image_input["image_embeds"].type(self.visual.dtype)
@@ -1559,12 +1559,10 @@ class Glm4vForConditionalGeneration(
                     self.visual, pixel_values, grid_thw.tolist(), rope_type="rope_3d"
                 )
             else:
-                image_embeds = self.visual(pixel_values, grid_thw=grid_thw.tolist())
+                image_embeds = self.visual(pixel_values, grid_thw=grid_thw)
+
         merge_size = self.visual.spatial_merge_size
-        sizes = (
-            torch.tensor(grid_thw_list, dtype=torch.long).prod(-1)
-            // (merge_size * merge_size)
-        ).tolist()
+        sizes = (grid_thw.prod(-1) // merge_size // merge_size).tolist()
         return image_embeds.split(sizes)
 
     def _process_video_input(
@@ -1572,7 +1570,6 @@ class Glm4vForConditionalGeneration(
     ) -> tuple[torch.Tensor, ...]:
         grid_thw = video_input["video_grid_thw"]
         assert grid_thw.ndim == 2
-        grid_thw_list = grid_thw.tolist()
 
         if video_input["type"] == "video_embeds":
             video_embeds = video_input["video_embeds"].type(self.visual.dtype)
@@ -1588,15 +1585,11 @@ class Glm4vForConditionalGeneration(
                     rope_type="rope_3d",
                 )
             else:
-                video_embeds = self.visual(
-                    pixel_values_videos, grid_thw=grid_thw.tolist()
-                )
+                video_embeds = self.visual(pixel_values_videos, grid_thw=grid_thw)
+
         # Split concatenated embeddings for each video item.
         merge_size = self.visual.spatial_merge_size
-        sizes = (
-            torch.tensor(grid_thw_list, dtype=torch.long).prod(-1)
-            // (merge_size * merge_size)
-        ).tolist()
+        sizes = (grid_thw.prod(-1) // merge_size // merge_size).tolist()
         return video_embeds.split(sizes)
 
     def _parse_and_validate_multimodal_inputs(self, **kwargs: object) -> dict:

vllm/model_executor/models/hunyuan_vision.py

@@ -563,7 +563,7 @@ def _hunyuan_vl_field_config(hf_inputs: Mapping[str, torch.Tensor]):
     return dict(
         pixel_values=MultiModalFieldConfig.flat_from_sizes("image", image_grid_sizes),
         image_embeds=MultiModalFieldConfig.flat_from_sizes("image", image_grid_sizes),
-        image_grid_thw=MultiModalFieldConfig.batched("image"),
+        image_grid_thw=MultiModalFieldConfig.batched("image", keep_on_cpu=True),
     )
 
 
@@ -786,8 +786,6 @@ class HunYuanVLForConditionalGeneration(
     SupportsQuant,
     SupportsXDRoPE,
 ):
-    multimodal_cpu_fields = {"image_grid_thw"}
-
     # To ensure correct weight loading and mapping.
     hf_to_vllm_mapper = WeightsMapper(
         orig_to_new_prefix={

vllm/model_executor/models/interfaces.py

@@ -84,9 +84,9 @@ class SupportsMultiModal(Protocol):
     `vllm.multimodal.utils.group_mm_kwargs_by_modality` to use.
     """
 
-    multimodal_cpu_fields: ClassVar[Set[str]] = frozenset()
+    multimodal_cpu_fields: ClassVar[Set[str] | None] = None
     """
-    A set indicating CPU-only multimodal fields.
+    [DEPRECATED] A set indicating CPU-only multimodal fields.
     """
 
     _processor_factory: ClassVar[_ProcessorFactories]
@@ -279,6 +279,15 @@ def supports_multimodal(
                 "please remove the override from your model."
             )
 
+        multimodal_cpu_fields = getattr(model, "multimodal_cpu_fields", None)
+        if multimodal_cpu_fields is not None:
+            raise ValueError(
+                "`multimodal_cpu_fields` is no longer effective, "
+                "please set `keep_on_cpu=True` in `MultiModalFieldConfig` "
+                "(refer to https://github.com/vllm-project/vllm/pull/30181), "
+                "and then remove the override from your model."
+            )
+
     return res
 
 

vllm/model_executor/models/opencua.py

@@ -201,8 +201,6 @@ class OpenCUADummyInputsBuilder(Qwen2VLDummyInputsBuilder):
     dummy_inputs=OpenCUADummyInputsBuilder,
 )
 class OpenCUAForConditionalGeneration(Qwen2_5_VLForConditionalGeneration):
-    multimodal_cpu_fields = {"image_grid_thw"}
-
     packed_modules_mapping = {
         "qkv_proj": ["q_proj", "k_proj", "v_proj"],
         "gate_up_proj": ["gate_proj", "up_proj"],

vllm/model_executor/models/qwen2_5_vl.py

@@ -1039,8 +1039,6 @@ class Qwen2_5_VLForConditionalGeneration(
     SupportsMultiModalPruning,
     SupportsMRoPE,
 ):
-    multimodal_cpu_fields = {"image_grid_thw", "video_grid_thw"}
-
     packed_modules_mapping = {
         "qkv_proj": ["q_proj", "k_proj", "v_proj"],
         "gate_up_proj": ["gate_proj", "up_proj"],

vllm/model_executor/models/qwen2_vl.py

@@ -811,14 +811,14 @@ def _create_qwen2vl_field_factory(
             image_embeds=MultiModalFieldConfig.flat_from_sizes(
                 "image", image_embed_grid_sizes
             ),
-            image_grid_thw=MultiModalFieldConfig.batched("image"),
+            image_grid_thw=MultiModalFieldConfig.batched("image", keep_on_cpu=True),
             pixel_values_videos=MultiModalFieldConfig.flat_from_sizes(
                 "video", video_grid_sizes
             ),
             video_embeds=MultiModalFieldConfig.flat_from_sizes(
                 "video", video_embed_grid_sizes
             ),
-            video_grid_thw=MultiModalFieldConfig.batched("video"),
+            video_grid_thw=MultiModalFieldConfig.batched("video", keep_on_cpu=True),
         )
 
     return _qwen2vl_field_config
@@ -1131,8 +1131,6 @@ class Qwen2VLMultiModalProcessor(BaseMultiModalProcessor[Qwen2VLProcessingInfo])
 class Qwen2VLForConditionalGeneration(
     nn.Module, SupportsMultiModal, SupportsLoRA, SupportsPP, SupportsMRoPE
 ):
-    multimodal_cpu_fields = {"image_grid_thw", "video_grid_thw"}
-
     # To ensure correct weight loading and mapping.
     hf_to_vllm_mapper = WeightsMapper(
         orig_to_new_prefix={
@@ -1393,9 +1391,11 @@ class Qwen2VLForConditionalGeneration(
         else:
             pixel_values_videos = video_input["pixel_values_videos"]
             if self.use_data_parallel:
-                grid_thw_list = grid_thw.tolist()
                 return run_dp_sharded_mrope_vision_model(
-                    self.visual, pixel_values_videos, grid_thw_list, rope_type="rope_3d"
+                    self.visual,
+                    pixel_values_videos,
+                    grid_thw.tolist(),
+                    rope_type="rope_3d",
                 )
             else:
                 video_embeds = self.visual(pixel_values_videos, grid_thw=grid_thw)

vllm/model_executor/models/qwen3_vl.py

@@ -984,14 +984,14 @@ class Qwen3VLMultiModalProcessor(BaseMultiModalProcessor[Qwen3VLProcessingInfo])
             image_embeds=MultiModalFieldConfig.flat_from_sizes(
                 "image", image_grid_sizes
             ),
-            image_grid_thw=MultiModalFieldConfig.batched("image"),
+            image_grid_thw=MultiModalFieldConfig.batched("image", keep_on_cpu=True),
             pixel_values_videos=MultiModalFieldConfig.flat_from_sizes(
                 "video", video_grid_sizes
             ),
             video_embeds=MultiModalFieldConfig.flat_from_sizes(
                 "video", video_grid_sizes
             ),
-            video_grid_thw=MultiModalFieldConfig.batched("video"),
+            video_grid_thw=MultiModalFieldConfig.batched("video", keep_on_cpu=True),
         )
 
     def _get_prompt_updates(
@@ -1190,8 +1190,6 @@ class Qwen3VLForConditionalGeneration(
     SupportsMRoPE,
     SupportsEagle3,
 ):
-    multimodal_cpu_fields = {"image_grid_thw", "video_grid_thw"}
-
     packed_modules_mapping = {
         "qkv_proj": [
             "q_proj",

vllm/multimodal/inputs.py

@@ -3,7 +3,7 @@
 
 from abc import ABC, abstractmethod
 from collections import UserDict, defaultdict
-from collections.abc import Mapping, Sequence, Set
+from collections.abc import Mapping, Sequence
 from dataclasses import dataclass
 from functools import partial
 from itertools import accumulate
@@ -223,6 +223,23 @@ def nested_tensors_equal(a: NestedTensors, b: NestedTensors) -> bool:
     return a == b
 
 
+def _nested_tensors_h2d(
+    tensors: NestedTensors,
+    device: torch.types.Device,
+) -> NestedTensors:
+    if device is None:
+        return tensors
+
+    return json_map_leaves(
+        (
+            lambda x: x.to(device=device, non_blocking=True)
+            if isinstance(x, torch.Tensor)
+            else x
+        ),
+        tensors,
+    )
+
+
 BatchedTensorInputs: TypeAlias = dict[str, NestedTensors]
 """
 A dictionary containing nested tensors which have been batched via
@@ -334,7 +351,7 @@ class MultiModalFieldElem:
         )  # noqa: E721
 
 
-@dataclass(frozen=True)
+@dataclass(frozen=True, kw_only=True)
 class BaseMultiModalField(ABC):
     """
     Defines how to interpret tensor data belonging to a keyword argument in
@@ -342,6 +359,12 @@ class BaseMultiModalField(ABC):
     multi-modal items, and vice versa.
     """
 
+    keep_on_cpu: bool = False
+    """
+    If `True`, then this field is excluded from being moved to the accelerator
+    when `MultiModalKwargsItems.get_data()` is called to batch the data.
+    """
+
     def _field_factory(self, *, modality: str, key: str):
         f = partial(
             MultiModalFieldElem,
@@ -386,6 +409,7 @@ class BaseMultiModalField(ABC):
         self,
         elems: list[MultiModalFieldElem],
         *,
+        device: torch.types.Device = None,
         pin_memory: bool = False,
     ) -> NestedTensors:
         """
@@ -399,11 +423,17 @@ class BaseMultiModalField(ABC):
         if len(set(field_types)) > 1:
             raise ValueError(f"Cannot merge different {field_types=}")
 
+        if device is not None and self.keep_on_cpu:
+            device = "cpu"
+        if pin_memory and self.keep_on_cpu:
+            pin_memory = False
+
         batch = [elem.data for elem in elems]
-        return self._reduce_data(batch, pin_memory=pin_memory)
+        out = self._reduce_data(batch, pin_memory=pin_memory)
+        return _nested_tensors_h2d(out, device=device)
 
 
-@dataclass(frozen=True)
+@dataclass(frozen=True, kw_only=True)
 class MultiModalBatchedField(BaseMultiModalField):
     """
     Info:
@@ -445,7 +475,7 @@ class MultiModalBatchedField(BaseMultiModalField):
         return batch
 
 
-@dataclass(frozen=True)
+@dataclass(frozen=True, kw_only=True)
 class MultiModalFlatField(BaseMultiModalField):
     """
     Info:
@@ -505,7 +535,7 @@ class MultiModalFlatField(BaseMultiModalField):
         return [e for elem in batch for e in elem]
 
 
-@dataclass(frozen=True)
+@dataclass(frozen=True, kw_only=True)
 class MultiModalSharedField(BaseMultiModalField):
     """
     Info:
@@ -532,9 +562,10 @@ class MultiModalSharedField(BaseMultiModalField):
         return batch[0]
 
 
+@dataclass(frozen=True)
 class MultiModalFieldConfig:
     @staticmethod
-    def batched(modality: str):
+    def batched(modality: str, *, keep_on_cpu: bool = False):
         """
         Defines a field where an element in the batch is obtained by
         indexing into the first dimension of the underlying data.
@@ -542,6 +573,7 @@ class MultiModalFieldConfig:
         Args:
             modality: The modality of the multi-modal item that uses this
                 keyword argument.
+            keep_on_cpu: Whether to keep this field on the CPU for the model inputs.
 
         Example:
 
@@ -558,7 +590,7 @@ class MultiModalFieldConfig:
         ```
         """
         return MultiModalFieldConfig(
-            field=MultiModalBatchedField(),
+            field=MultiModalBatchedField(keep_on_cpu=keep_on_cpu),
             modality=modality,
         )
 
@@ -567,6 +599,8 @@ class MultiModalFieldConfig:
         modality: str,
         slices: Sequence[slice] | Sequence[Sequence[slice]],
         dim: int = 0,
+        *,
+        keep_on_cpu: bool = False,
     ):
         """
         Defines a field where an element in the batch is obtained by
@@ -579,6 +613,7 @@ class MultiModalFieldConfig:
                 slices (dim>0) that is used to extract the data corresponding
                 to it.
             dim: The dimension to extract data, default to 0.
+            keep_on_cpu: Whether to keep this field on the CPU for the model inputs.
 
         Example:
 
@@ -613,12 +648,22 @@ class MultiModalFieldConfig:
         ```
         """
         return MultiModalFieldConfig(
-            field=MultiModalFlatField(slices=slices, dim=dim),
+            field=MultiModalFlatField(
+                slices=slices,
+                dim=dim,
+                keep_on_cpu=keep_on_cpu,
+            ),
             modality=modality,
         )
 
     @staticmethod
-    def flat_from_sizes(modality: str, size_per_item: "torch.Tensor", dim: int = 0):
+    def flat_from_sizes(
+        modality: str,
+        size_per_item: "torch.Tensor",
+        dim: int = 0,
+        *,
+        keep_on_cpu: bool = False,
+    ):
         """
         Defines a field where an element in the batch is obtained by
         slicing along the first dimension of the underlying data.
@@ -629,6 +674,7 @@ class MultiModalFieldConfig:
             size_per_item: For each multi-modal item, the size of the slice
                 that is used to extract the data corresponding to it.
             dim: The dimension to slice, default to 0.
+            keep_on_cpu: Whether to keep this field on the CPU for the model inputs.
 
         Example:
 
@@ -676,10 +722,20 @@ class MultiModalFieldConfig:
             for i in range(len(size_per_item))
         ]
 
-        return MultiModalFieldConfig.flat(modality, slices, dim=dim)
+        return MultiModalFieldConfig.flat(
+            modality,
+            slices,
+            dim=dim,
+            keep_on_cpu=keep_on_cpu,
+        )
 
     @staticmethod
-    def shared(modality: str, batch_size: int):
+    def shared(
+        modality: str,
+        batch_size: int,
+        *,
+        keep_on_cpu: bool = False,
+    ):
         """
         Defines a field where an element in the batch is obtained by
         taking the entirety of the underlying data.
@@ -690,6 +746,7 @@ class MultiModalFieldConfig:
             modality: The modality of the multi-modal item that uses this
                 keyword argument.
             batch_size: The number of multi-modal items which share this data.
+            keep_on_cpu: Whether to keep this field on the CPU for the model inputs.
 
         Example:
 
@@ -708,18 +765,15 @@ class MultiModalFieldConfig:
         ```
         """
         return MultiModalFieldConfig(
-            field=MultiModalSharedField(batch_size),
+            field=MultiModalSharedField(
+                batch_size=batch_size,
+                keep_on_cpu=keep_on_cpu,
+            ),
             modality=modality,
         )
 
-    def __init__(self, field: BaseMultiModalField, modality: str) -> None:
-        super().__init__()
-
-        self.field = field
-        self.modality = modality
-
-    def __repr__(self) -> str:
-        return f"MultiModalFieldConfig(field={self.field}, modality={self.modality})"
+    field: BaseMultiModalField
+    modality: str
 
     def build_elems(
         self,
@@ -744,7 +798,7 @@ class MultiModalKwargsItem(UserDict[str, MultiModalFieldElem]):
             modality=modality,
             key="dummy",
             data=torch.empty(nbytes, dtype=torch.uint8),
-            field=MultiModalSharedField(1),
+            field=MultiModalSharedField(batch_size=1),
         )
         return MultiModalKwargsItem.from_elems([mm_elem])
 
@@ -844,7 +898,6 @@ class MultiModalKwargsItems(UserDict[str, Sequence[_I]]):
         *,
         device: torch.types.Device = None,
         pin_memory: bool = False,
-        cpu_fields: Set[str] = frozenset(),
     ) -> BatchedTensorInputs:
         """Construct a dictionary of keyword arguments to pass to the model."""
         elems_by_key = defaultdict[str, list[MultiModalFieldElem]](list)
@@ -859,21 +912,14 @@ class MultiModalKwargsItems(UserDict[str, Sequence[_I]]):
                     elems_by_key[key].append(elem)
 
         data = {
-            key: elems[0].field.reduce_data(elems, pin_memory=pin_memory)
+            key: elems[0].field.reduce_data(
+                elems,
+                device=device,
+                pin_memory=pin_memory,
+            )
             for key, elems in elems_by_key.items()
         }
 
-        if device is not None:
-            for k in data.keys() - cpu_fields:
-                data[k] = json_map_leaves(
-                    (
-                        lambda x: x.to(device=device, non_blocking=True)
-                        if isinstance(x, torch.Tensor)
-                        else x
-                    ),
-                    data[k],
-                )
-
         return data
 
 

vllm/multimodal/utils.py

@@ -413,7 +413,7 @@ def group_mm_kwargs_by_modality(
     device: torch.types.Device = None,
     pin_memory: bool = False,
     merge_by_field_config: bool | None = None,
-    multimodal_cpu_fields: Set[str] = frozenset(),
+    multimodal_cpu_fields: Set[str] | None = None,
 ) -> Generator[tuple[str, int, BatchedTensorInputs], None, None]:
     """Group consecutive `MultiModalKwargsItem`s from `mm_kwargs` with the same
     modality together into the same `MultiModalKwargs` instance.
@@ -431,6 +431,11 @@ def group_mm_kwargs_by_modality(
             "The `merge_by_field_config` argument of `group_mm_kwargs_by_modality` "
             "is deprecated and will be removed in v0.13."
         )
+    if multimodal_cpu_fields is not None:
+        logger.warning_once(
+            "The `multimodal_cpu_fields` argument of `group_mm_kwargs_by_modality` "
+            "is deprecated and will be removed in v0.13."
+        )
 
     from vllm.multimodal.inputs import MultiModalKwargsItems
 
@@ -440,7 +445,6 @@ def group_mm_kwargs_by_modality(
         mm_kwargs_data = mm_kwargs_items.get_data(
             device=device,
             pin_memory=pin_memory,
-            cpu_fields=multimodal_cpu_fields,
         )
 
         yield modality, len(items_lst), mm_kwargs_data

vllm/v1/serial_utils.py

@@ -269,10 +269,11 @@ class MsgpackEncoder:
         name = MMF_CLASS_TO_FACTORY.get(field.__class__)
         if not name:
             raise TypeError(f"Unsupported field type: {field.__class__}")
+
         # We just need to copy all of the field values in order
         # which will be then used to reconstruct the field.
-        field_values = (getattr(field, f.name) for f in dataclasses.fields(field))
-        return name, *field_values
+        factory_kw = {f.name: getattr(field, f.name) for f in dataclasses.fields(field)}
+        return name, factory_kw
 
 
 class MsgpackDecoder:
@@ -392,15 +393,15 @@ class MsgpackDecoder:
             obj["data"] = self._decode_nested_tensors(obj["data"])
 
         # Reconstruct the field processor using MultiModalFieldConfig
-        factory_meth_name, *field_args = obj["field"]
+        factory_meth_name, factory_kw = obj["field"]
         factory_meth = getattr(MultiModalFieldConfig, factory_meth_name)
 
         # Special case: decode the union "slices" field of
         # MultiModalFlatField
         if factory_meth_name == "flat":
-            field_args[0] = self._decode_nested_slices(field_args[0])
+            factory_kw["slices"] = self._decode_nested_slices(factory_kw["slices"])
 
-        obj["field"] = factory_meth(None, *field_args).field
+        obj["field"] = factory_meth("", **factory_kw).field
         return MultiModalFieldElem(**obj)
 
     def _decode_nested_tensors(self, obj: Any) -> NestedTensors:

vllm/v1/worker/gpu_model_runner.py

@@ -1097,7 +1097,6 @@ class GPUModelRunner(
             device=self.device,
             pin_memory=self.pin_memory,
             merge_by_field_config=model.merge_by_field_config,
-            multimodal_cpu_fields=model.multimodal_cpu_fields,
         ):
             mm_kwargs_combined.update(mm_kwargs_group)
 
@@ -2109,7 +2108,6 @@ class GPUModelRunner(
             mm_kwargs,
             device=self.device,
             pin_memory=self.pin_memory,
-            multimodal_cpu_fields=model.multimodal_cpu_fields,
         ):
             curr_group_outputs: list[torch.Tensor] = []
 
@@ -2135,7 +2133,6 @@ class GPUModelRunner(
                             [video_mm_kwargs_item],
                             device=self.device,
                             pin_memory=self.pin_memory,
-                            multimodal_cpu_fields=model.multimodal_cpu_fields,
                         )
                     )
 
@@ -3887,14 +3884,12 @@ class GPUModelRunner(
         dummy_mm_item = dummy_mm_data[modality][0]
         dummy_mm_items = [dummy_mm_item] * max_items_per_batch
 
-        model = cast(SupportsMultiModal, self.model)
         return next(
             mm_kwargs_group
             for _, _, mm_kwargs_group in group_mm_kwargs_by_modality(
                 dummy_mm_items,
                 device=self.device,
                 pin_memory=self.pin_memory,
-                multimodal_cpu_fields=model.multimodal_cpu_fields,
             )
         )
 

vllm/v1/worker/tpu_model_runner.py

@@ -969,7 +969,6 @@ class TPUModelRunner(LoRAModelRunnerMixin, KVConnectorModelRunnerMixin):
             mm_kwargs,
             device=self.device,
             pin_memory=self.pin_memory,
-            multimodal_cpu_fields=model.multimodal_cpu_fields,
         ):
             # Run the encoder.
             # `curr_group_outputs` is either of the following:
@@ -2050,14 +2049,12 @@ class TPUModelRunner(LoRAModelRunnerMixin, KVConnectorModelRunnerMixin):
         dummy_mm_item = dummy_mm_data[modality][0]
         dummy_mm_items = [dummy_mm_item] * max_items_per_batch
 
-        model = cast(SupportsMultiModal, self.model)
         return next(
             grouped_mm_kwargs
             for _, _, grouped_mm_kwargs in group_mm_kwargs_by_modality(
                 dummy_mm_items,
                 device=self.device,
                 pin_memory=self.pin_memory,
-                multimodal_cpu_fields=model.multimodal_cpu_fields,
             )
         )