enable llama3.1-8B on xpu (#9434)

python/sglang/srt/layers/layernorm.py

@@ -28,6 +28,7 @@ from sglang.srt.utils import (
     is_cuda,
     is_hip,
     is_npu,
+    is_xpu,
     supports_custom_op,
 )
 
@@ -37,6 +38,7 @@ _is_npu = is_npu()
 _use_aiter = get_bool_env_var("SGLANG_USE_AITER") and _is_hip
 _is_cpu_amx_available = cpu_has_amx_support()
 _is_cpu = is_cpu()
+_is_xpu = is_xpu()
 
 if _is_cuda:
     from flashinfer.norm import fused_add_rmsnorm as flashinfer_fused_add_rmsnorm
@@ -327,7 +329,9 @@ class Gemma3RMSNorm(CustomOp):
         return f"{tuple(self.weight.shape)}, eps={self.eps}"
 
 
-if not (_is_cuda or _is_hip or _is_npu or (_is_cpu and _is_cpu_amx_available)):
+if not (
+    _is_cuda or _is_hip or _is_npu or (_is_cpu and _is_cpu_amx_available) or _is_xpu
+):
     logger.info(
         "sgl-kernel layernorm implementation is not available on current platform. Fallback to other kernel libraries."
     )