[NVIDIA] Fix breakage of using trtllm-gen fp8 moe (#8773)

python/sglang/srt/layers/moe/ep_moe/layer.py

@@ -673,66 +673,6 @@ class DeepEPMoE(EPMoE):
         return down_output
 
 
-class FlashInferEPMoE(EPMoE):
-    def __init__(self, *args, **kwargs):
-        renormalize = kwargs.pop("renormalize", True)
-        num_fused_shared_experts = kwargs.pop("num_fused_shared_experts", 0)
-        use_grouped_topk = kwargs.pop("use_grouped_topk", False)
-        num_expert_group = kwargs.pop("num_expert_group", None)
-        topk_group = kwargs.pop("topk_group", None)
-        correction_bias = kwargs.pop("correction_bias", None)
-        super().__init__(*args, **kwargs)
-        self.renormalize = renormalize
-        self.num_fused_shared_experts = num_fused_shared_experts
-        self.use_grouped_topk = use_grouped_topk
-        if self.use_grouped_topk:
-            assert num_expert_group is not None and topk_group is not None
-        self.num_expert_group = num_expert_group
-        self.topk_group = topk_group
-        self.correction_bias = correction_bias
-        self.use_flashinfer_trtllm_moe = should_use_flashinfer_trtllm_moe()
-
-    def forward(self, hidden_states: torch.Tensor, router_logits: torch.Tensor):
-        assert self.use_flashinfer_trtllm_moe
-        assert (
-            self.activation == "silu"
-        ), "Only silu is supported for flashinfer blockscale fp8 moe"
-        assert (
-            self.renormalize
-        ), "Renormalize is required for flashinfer blockscale fp8 moe"
-        assert (
-            self.num_fused_shared_experts == 0
-        ), "Fused shared experts are not supported for flashinfer blockscale fp8 moe"
-        a_q, a_sf = sglang_per_token_group_quant_fp8(hidden_states, self.block_shape[1])
-        # NOTE: scales of hidden states have to be transposed!
-        a_sf_t = a_sf.t().contiguous()
-        from flashinfer.fused_moe import trtllm_fp8_block_scale_moe
-
-        return trtllm_fp8_block_scale_moe(
-            routing_logits=router_logits.to(torch.float32),
-            routing_bias=self.correction_bias.to(hidden_states.dtype),
-            hidden_states=a_q,
-            hidden_states_scale=a_sf_t,
-            gemm1_weights=self.w13_weight,
-            gemm1_weights_scale=self.w13_weight_scale_inv,
-            gemm2_weights=self.w2_weight,
-            gemm2_weights_scale=self.w2_weight_scale_inv,
-            num_experts=self.num_experts,
-            top_k=self.top_k,
-            n_group=self.num_expert_group,
-            topk_group=self.topk_group,
-            intermediate_size=self.w2_weight.shape[2],
-            local_expert_offset=self.start_expert_id,
-            local_num_experts=self.num_local_experts,
-            routed_scaling_factor=self.routed_scaling_factor,
-            tile_tokens_dim=get_tile_tokens_dim(
-                hidden_states.shape[0], self.top_k, self.num_experts
-            ),
-            routing_method_type=2,  # DeepSeek-styled routing method
-            use_shuffled_weight=False,
-        )
-
-
 def get_moe_impl_class():
     if global_server_args_dict["moe_a2a_backend"].is_deepep():
         return DeepEPMoE
@@ -752,8 +692,10 @@ def get_moe_impl_class():
         except:
             pass
 
+    if should_use_flashinfer_trtllm_moe():
+        return FlashInferFusedMoE
     if global_server_args_dict["enable_flashinfer_cutlass_moe"]:
         return FusedMoE
     if get_moe_expert_parallel_world_size() > 1:
-        return FlashInferEPMoE if should_use_flashinfer_trtllm_moe() else EPMoE
-    return FlashInferFusedMoE if should_use_flashinfer_trtllm_moe() else FusedMoE
+        return EPMoE
+    return FusedMoE

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

@@ -763,8 +763,13 @@ class FlashInferFusedMoE(FusedMoE):
         self.num_expert_group = num_expert_group
         self.topk_group = topk_group
         self.correction_bias = correction_bias
+        self.use_flashinfer_trtllm_moe = should_use_flashinfer_trtllm_moe()
 
-    def forward(self, hidden_states: torch.Tensor, router_logits: torch.Tensor):
+    def forward(self, hidden_states: torch.Tensor, topk_output: tuple):
+        assert self.use_flashinfer_trtllm_moe
+        assert (
+            self.activation == "silu"
+        ), "Only silu is supported for flashinfer blockscale fp8 moe"
         assert self.quant_method is not None
         assert (
             self.renormalize
@@ -772,6 +777,14 @@ class FlashInferFusedMoE(FusedMoE):
         assert (
             self.num_fused_shared_experts == 0
         ), "Fused shared experts are not supported for flashinfer blockscale fp8 moe"
+
+        # TRTLLM mode expects (TopK_config, router_logits) tuple
+        if not isinstance(topk_output, tuple) or len(topk_output) != 2:
+            raise ValueError(
+                f"FlashInferFusedMoE expects (TopK_config, router_logits) tuple, got {type(topk_output)}"
+            )
+        _, router_logits = topk_output
+
         # Matrix multiply.
         final_hidden_states = self.quant_method.apply_with_router_logits(
             layer=self,