fix #4209

DeepSpeed ZeRO3 has inflight param error when calling model.eval()

src/llamafactory/train/trainer_utils.py

@@ -1,4 +1,3 @@
-from contextlib import contextmanager
 from typing import TYPE_CHECKING, Callable, Dict, List, Optional, Tuple, Union
 
 import torch
@@ -19,7 +18,6 @@ if is_galore_available():
 
 
 if TYPE_CHECKING:
-    from accelerate import Accelerator
     from transformers import PreTrainedModel, Seq2SeqTrainingArguments
     from trl import AutoModelForCausalLMWithValueHead
 
@@ -154,17 +152,6 @@ def create_reward_model(
         return reward_model
 
 
-@contextmanager
-def get_ref_context(accelerator: "Accelerator", model: "PreTrainedModel"):
-    r"""
-    Gets adapter context for the reference model.
-    """
-    with accelerator.unwrap_model(model).disable_adapter():
-        model.eval()
-        yield
-        model.train()
-
-
 def _get_decay_parameter_names(model: "PreTrainedModel") -> List[str]:
     r"""
     Returns a list of names of parameters with weight decay. (weights in non-layernorm layers)