[TBO] fix cuda graph intermittently becomes disabled bug (#18320)

python/sglang/srt/batch_overlap/two_batch_overlap.py

@@ -440,18 +440,23 @@ class TboDPAttentionPreparer:
 
     @staticmethod
     def _compute_global_forward_mode(forward_modes):
-        forward_modes_excluding_idle = [
-            x for x in forward_modes if x != ForwardMode.IDLE.value
+        forward_modes_excluding_idle_and_prebuilt = [
+            x
+            for x in forward_modes
+            if x != ForwardMode.IDLE.value and x != ForwardMode.PREBUILT.value
         ]
 
-        if not forward_modes_excluding_idle:
+        if not forward_modes_excluding_idle_and_prebuilt:
             return ForwardMode.IDLE, False
 
         forward_mode_agree = TboDPAttentionPreparer._is_all_same(
-            forward_modes_excluding_idle
+            forward_modes_excluding_idle_and_prebuilt
         )
+
         global_forward_mode = (
-            ForwardMode(forward_modes_excluding_idle[0]) if forward_mode_agree else None
+            ForwardMode(forward_modes_excluding_idle_and_prebuilt[0])
+            if forward_mode_agree
+            else None
         )
         return global_forward_mode, forward_mode_agree