refactor: simplify Llama2Model constructor to take llm_config directly

ghstack-source-id: 2c66b9f
Pull Request resolved: pytorch/executorch#11170

Author: jackzhxng

examples/models/llama/export_llama_lib.py

@@ -1226,7 +1226,7 @@ def _load_llama_model(
         EagerModelFactory.create_model(
             module_name,
             model_class_name,
-            llm_config=llm_config,
+            model_args={"llm_config": llm_config},
         )
     )
 

examples/models/llama/model.py

@@ -36,19 +36,18 @@ def convert_to_llama_checkpoint(**kwargs):
 
 
 class Llama2Model(EagerModelBase):
-    def __init__(self, **kwargs):
+    def __init__(self, llm_config):
         resource_dir = get_default_model_resource_dir(__file__)
 
+        self.llm_config = llm_config
+        
         # Use single checkpoint file.
-        checkpoint_path = kwargs.get("checkpoint", None)
+        checkpoint_path = self.llm_config.base.checkpoint
         # Check if checkpoint_dir was provided for a sharded checkpoint.
-        checkpoint_dir = kwargs.get("checkpoint_dir", None)
+        checkpoint_dir = self.llm_config.base.checkpoint_dir
 
         # Params file.
-        params_path = kwargs.get("params", None)
-
-        self.llm_config = kwargs.get("llm_config")
-        assert self.llm_config is not None, "llm_config must be provided"
+        params_path = self.llm_config.base.params
 
         self.use_kv_cache = self.llm_config.model.use_kv_cache
         self.use_sdpa_with_kv_cache_op = self.llm_config.model.use_sdpa_with_kv_cache