CUTLASS NVFP4 GEMM improvement of SM120 (#21314)

python/sglang/srt/server_args.py

@@ -214,6 +214,7 @@ FP8_GEMM_RUNNER_BACKEND_CHOICES = [
 
 FP4_GEMM_RUNNER_BACKEND_CHOICES = [
     "auto",
+    "cutlass",
     "flashinfer_cudnn",
     "flashinfer_cutlass",
     "flashinfer_trtllm",
@@ -4709,7 +4710,8 @@ class ServerArgs:
             dest="fp4_gemm_runner_backend",
             help="Choose the runner backend for NVFP4 GEMM operations. "
             "Options: 'auto' (default; selects flashinfer_cudnn on SM120, flashinfer_cutlass otherwise), "
-            "'flashinfer_cutlass' (CUTLASS backend), "
+            "'cutlass' (SGLang CUTLASS kernel), "
+            "'flashinfer_cutlass' (FlashInfer CUTLASS backend), "
             "'flashinfer_cudnn' (FlashInfer cuDNN backend, optimal on CUDA 13+ with cuDNN 9.15+), "
             "'flashinfer_trtllm' (FlashInfer TensorRT-LLM backend, requires different weight preparation with shuffling). ",
         )