[config] update args (#7231)

Former-commit-id: f71a901840811bf560df671ec63a146ff99140c6

src/llamafactory/hparams/model_args.py

@@ -23,6 +23,8 @@ import torch
 from transformers.training_args import _convert_str_dict
 from typing_extensions import Self
 
+from ..extras.constants import AttentionFunction, EngineName, RopeScaling
+
 
 @dataclass
 class BaseModelArguments:
@@ -77,12 +79,12 @@ class BaseModelArguments:
         default=True,
         metadata={"help": "Whether or not to use memory-efficient model loading."},
     )
-    rope_scaling: Optional[Literal["linear", "dynamic", "yarn", "llama3"]] = field(
+    rope_scaling: Optional[RopeScaling] = field(
         default=None,
         metadata={"help": "Which scaling strategy should be adopted for the RoPE embeddings."},
     )
-    flash_attn: Literal["auto", "disabled", "sdpa", "fa2"] = field(
-        default="auto",
+    flash_attn: AttentionFunction = field(
+        default=AttentionFunction.AUTO,
         metadata={"help": "Enable FlashAttention for faster training and inference."},
     )
     shift_attn: bool = field(
@@ -129,8 +131,8 @@ class BaseModelArguments:
         default=False,
         metadata={"help": "Whether or not to randomly initialize the model weights."},
     )
-    infer_backend: Literal["huggingface", "vllm"] = field(
-        default="huggingface",
+    infer_backend: EngineName = field(
+        default=EngineName.HF,
         metadata={"help": "Backend engine used at inference."},
     )
     offload_folder: str = field(