[fix]添加VLLM_USE_LIGHTOP_FUSED_TOPP_TOPK控制lightop topp_topk融合算子开关

vllm/envs.py

@@ -309,6 +309,7 @@ if TYPE_CHECKING:
     VLLM_USE_LIGHTOP_FILL_MOE_ALIGN: bool = False
     VLLM_USE_LIGHTOP_RMS_ROPE_CONCAT: bool = False
     VLLM_USE_CUDA_GRAPH_SIZES: bool = False
+    VLLM_USE_LIGHTOP_FUSED_TOPP_TOPK: bool = False
 
 
 def get_default_cache_root():
@@ -1934,6 +1935,11 @@ environment_variables: dict[str, Callable[[], Any]] = {
     "VLLM_USE_CUDA_GRAPH_SIZES":
         lambda: (os.getenv("VLLM_USE_CUDA_GRAPH_SIZES", "False").lower() in
                 ("true", "1")),
+
+    #If set to 1/True, enable fused topk topk kernel in lightop
+    "VLLM_USE_LIGHTOP_FUSED_TOPP_TOPK":
+        lambda: (os.environ.get("VLLM_USE_LIGHTOP_FUSED_TOPP_TOPK", "False").lower() in
+                    ("true", "1")),
 }
 
 # --8<-- [end:env-vars-definition]