[MoE Refactor] Aiter Experts for BF16 MoE (#31542)

Signed-off-by: Yongye Zhu <zyy1102000@gmail.com>
Co-authored-by: Robert Shaw <114415538+robertgshaw2-redhat@users.noreply.github.com>

vllm/model_executor/layers/fused_moe/unquantized_fused_moe_method.py

@@ -30,6 +30,9 @@ from vllm.model_executor.layers.fused_moe.modular_kernel import (
 from vllm.model_executor.layers.fused_moe.prepare_finalize import (
     MoEPrepareAndFinalizeNoEP,
 )
+from vllm.model_executor.layers.fused_moe.rocm_aiter_fused_moe import (
+    AiterExperts,
+)
 from vllm.model_executor.layers.quantization.utils.flashinfer_utils import (
     swap_w13_to_w31,
 )
@@ -60,12 +63,6 @@ class UnquantizedFusedMoEMethod(FusedMoEMethodBase, CustomOp):
         super().__init__(moe)
 
         self.rocm_aiter_moe_enabled = rocm_aiter_ops.is_fused_moe_enabled()
-        if self.rocm_aiter_moe_enabled:
-            from .rocm_aiter_fused_moe import rocm_aiter_fused_experts
-
-            self.rocm_aiter_fused_experts = rocm_aiter_fused_experts
-        else:
-            self.rocm_aiter_fused_experts = None  # type: ignore
 
         # FlashInfer CUTLASS MoE is only supported on Hopper and later GPUS
         self.flashinfer_cutlass_moe_enabled = (
@@ -207,14 +204,6 @@ class UnquantizedFusedMoEMethod(FusedMoEMethodBase, CustomOp):
         layer.w13_weight.data = self._maybe_pad_weight(layer.w13_weight.data)
         layer.w2_weight.data = self._maybe_pad_weight(layer.w2_weight.data)
 
-        if self.rocm_aiter_moe_enabled:
-            shuffled_w13, shuffled_w2 = rocm_aiter_ops.shuffle_weights(
-                layer.w13_weight.data, layer.w2_weight.data
-            )
-
-            layer.w13_weight.data = shuffled_w13
-            layer.w2_weight.data = shuffled_w2
-
         if current_platform.is_xpu():
             import intel_extension_for_pytorch as ipex
 
@@ -258,7 +247,21 @@ class UnquantizedFusedMoEMethod(FusedMoEMethodBase, CustomOp):
                 layer.cpu_fused_moe = cpu_fused_moe.CPUFusedMOE(layer)
         elif current_platform.is_cuda_alike():
             self.moe_quant_config = self.get_fused_moe_quant_config(layer)
-            if self.flashinfer_cutlass_moe_enabled:
+            if self.rocm_aiter_moe_enabled:
+                shuffled_w13, shuffled_w2 = rocm_aiter_ops.shuffle_weights(
+                    layer.w13_weight.data, layer.w2_weight.data
+                )
+                replace_parameter(layer, "w13_weight", shuffled_w13)
+                replace_parameter(layer, "w2_weight", shuffled_w2)
+
+                self.use_inplace = True
+                self.kernel = mk.FusedMoEModularKernel(
+                    MoEPrepareAndFinalizeNoEP(),
+                    AiterExperts(self.moe_quant_config),
+                    shared_experts=None,
+                )
+
+            elif self.flashinfer_cutlass_moe_enabled:
                 self.use_inplace = False
                 # Swap halves to arrange as [w3; w1] (kernel expectation)
                 w13_weight = swap_w13_to_w31(layer.w13_weight.data)
@@ -315,18 +318,6 @@ class UnquantizedFusedMoEMethod(FusedMoEMethodBase, CustomOp):
             router_logits=router_logits,
         )
 
-        if self.rocm_aiter_moe_enabled:
-            result = self.rocm_aiter_fused_experts(
-                hidden_states=x,
-                w1=layer.w13_weight,
-                w2=layer.w2_weight,
-                topk_weights=topk_weights,
-                topk_ids=topk_ids,
-                expert_map=layer.expert_map,
-                activation=layer.activation,
-                apply_router_weight_on_input=layer.apply_router_weight_on_input,
-            )
-        else:
         result = self.kernel(
             hidden_states=x,
             w1=layer.w13_weight,