[Neuron] Support inference with transformers-neuronx (#2569)

vllm/model_executor/utils.py

@@ -1,10 +1,18 @@
 """Utils for model executor."""
 import random
+import importlib
 from typing import Any, Dict, Optional
 
 import numpy as np
 import torch
 
+from vllm.config import DeviceConfig, ModelConfig
+
+DEVICE_TO_MODEL_LOADER_MAP = {
+    "cuda": "model_loader",
+    "neuron": "neuron_model_loader",
+}
+
 
 def set_random_seed(seed: int) -> None:
     random.seed(seed)
@@ -33,3 +41,12 @@ def set_weight_attrs(
         assert not hasattr(
             weight, key), (f"Overwriting existing tensor attribute: {key}")
         setattr(weight, key, value)
+
+
+def get_model(model_config: ModelConfig, device_config: DeviceConfig,
+              **kwargs) -> torch.nn.Module:
+    model_loader_module = DEVICE_TO_MODEL_LOADER_MAP[device_config.device_type]
+    imported_model_loader = importlib.import_module(
+        f"vllm.model_executor.{model_loader_module}")
+    get_model_fn = imported_model_loader.get_model
+    return get_model_fn(model_config, device_config, **kwargs)