Sm120 scatter fallback (#31669)

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python/sglang/srt/layers/moe/fused_moe_triton/triton_kernels_moe.py

@@ -17,11 +17,17 @@ from triton_kernels.matmul_ogs import (
     ScatterIndx,
     matmul_ogs,
 )
+from triton_kernels.matmul_ogs_details.opt_flags import update_opt_flags_constraints
 from triton_kernels.numerics import InFlexData
 from triton_kernels.swiglu import swiglu_fn
 from triton_kernels.tensor import FP4
 
 from sglang.srt.utils import is_cuda
+from sglang.srt.utils.common import is_sm120_supported
+
+if is_sm120_supported():
+    # use the regular gather/scatter implementation for unsupported devices.
+    update_opt_flags_constraints({"is_persistent": False})
 
 if is_cuda():
     from sglang.jit_kernel.activation import gelu_and_mul, silu_and_mul