Make single-batch overlap compatible with offloading (#11614)

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

@@ -5,6 +5,7 @@ from typing import TYPE_CHECKING, Any, Dict, List, Optional, Union
 
 import torch
 
+from sglang.srt import single_batch_overlap
 from sglang.srt.layers.moe import (
     get_deepep_mode,
     get_moe_a2a_backend,
@@ -167,18 +168,20 @@ class DeepEPMoE(FusedMoE):
         topk_idx: torch.Tensor,
         topk_weights: torch.Tensor,
         forward_batch: ForwardBatch,
+        forward_shared_experts=None,
+        alt_stream=None,
     ):
-        dispatch_output = self.dispatch(
-            hidden_states, topk_idx, topk_weights, forward_batch
-        )
-        hidden_states = self.moe_impl(dispatch_output)
-        hidden_states = self.combine(
-            hidden_states,
-            dispatch_output.topk_idx,
-            dispatch_output.topk_weights,
-            forward_batch,
+        # We have to call SBO inside MoE to be compatible with hooks used in offloading
+        return single_batch_overlap.execute_sbo(
+            hidden_states=hidden_states,
+            topk_idx=topk_idx,
+            topk_weights=topk_weights,
+            forward_batch=forward_batch,
+            # SBO args
+            experts=self,
+            forward_shared_experts=forward_shared_experts,
+            alt_stream=alt_stream,
         )
-        return hidden_states
 
     def dispatch(
         self,

python/sglang/srt/models/deepseek_v2.py

@@ -872,7 +872,7 @@ class DeepseekV2MoE(nn.Module):
         if hidden_states.shape[0] > 0:
             # router_logits: (num_tokens, n_experts)
             router_logits = self.gate(hidden_states)
-            if not SboFlags.fuse_shared_experts_inside_sbo():
+            if not self._fuse_shared_experts_inside_sbo:
                 shared_output = self._forward_shared_experts(hidden_states)
             topk_weights, topk_idx, _ = self.topk(
                 hidden_states,
@@ -887,18 +887,27 @@ class DeepseekV2MoE(nn.Module):
                 hidden_states.device
             )
 
-        final_hidden_states, sbo_shared_output = single_batch_overlap.execute_sbo(
+        if self._fuse_shared_experts_inside_sbo:
+            shared_output = None
+
+            def _forward_shared_experts_and_put_results():
+                nonlocal shared_output
+                shared_output = self._forward_shared_experts(hidden_states)
+
+        final_hidden_states = self.experts(
             hidden_states=hidden_states,
             topk_idx=topk_idx,
             topk_weights=topk_weights,
             forward_batch=forward_batch,
-            # SBO args
-            forward_shared_experts=lambda: self._forward_shared_experts(hidden_states),
-            experts=self.experts,
-            alt_stream=self.alt_stream,
+            **(
+                dict(
+                    forward_shared_experts=_forward_shared_experts_and_put_results,
+                    alt_stream=self.alt_stream,
+                )
+                if self._fuse_shared_experts_inside_sbo
+                else {}
+            ),
         )
-        if sbo_shared_output is not None:
-            shared_output = sbo_shared_output
 
         if shared_output is not None:
             x = shared_output

python/sglang/srt/single_batch_overlap.py

@@ -42,7 +42,7 @@ class CombineOverlapArgs:
     wait_event: torch.cuda.Event
     num_sms: int
     signal: Optional[torch.Tensor] = None
-    threshold: int = -1
+    threshold: int = 0
 
 
 @dataclass
@@ -61,8 +61,6 @@ def execute_sbo(
     forward_batch: ForwardBatch,
     alt_stream: Optional = None,
 ):
-    shared_output = None
-
     dispatch_output = experts.dispatch(
         hidden_states, topk_idx, topk_weights, forward_batch
     )
@@ -82,7 +80,7 @@ def execute_sbo(
         with deep_gemm_wrapper.configure_deep_gemm_num_sms(
             meta_overlap_args["compute_num_sms"]
         ):
-            shared_output = forward_shared_experts()
+            forward_shared_experts()
 
     hidden_states = experts.combine(
         hidden_states,
@@ -92,7 +90,7 @@ def execute_sbo(
         overlap_args=combine_overlap_args,
     )
 
-    return hidden_states, shared_output
+    return hidden_states
 
 
 def _compute_overlap_args(dispatch_output, alt_stream):