[Bugfix][Frontend] Clear the P0 multimodal cache through the renderer

tests/entrypoints/test_async_omni_pause_sleep_routing.py

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM-Omni project
+
 """Unit tests for AR EngineCore vs diffusion worker pause/sleep routing."""
 
 from __future__ import annotations
@@ -7,6 +10,8 @@
 from unittest.mock import AsyncMock, call
 
 import pytest
+from vllm.renderers import BaseRenderer
+from vllm.v1.engine.input_processor import InputProcessor
 
 from vllm_omni.diffusion.data import CuMemTag, OmniACK
 from vllm_omni.entrypoints.async_omni import AsyncOmni
@@ -37,6 +42,22 @@ def _make_omni(*, stage_types: list[str]) -> AsyncOmni:
     return omni
 
 
+@pytest.mark.cpu
+def test_reset_mm_cache_routes_through_renderer(mocker):
+    async def run() -> None:
+        omni = object.__new__(AsyncOmni)
+        renderer = mocker.create_autospec(BaseRenderer, instance=True)
+        input_processor = mocker.create_autospec(InputProcessor, instance=True)
+        input_processor.renderer = renderer
+        omni.input_processor = input_processor
+
+        await omni.reset_mm_cache()
+
+        renderer.clear_mm_cache_async.assert_awaited_once_with()
+
+    asyncio.run(run())
+
+
 @pytest.mark.cpu
 def test_split_stage_ids_by_type():
     omni = _make_omni(stage_types=["llm", "diffusion", "llm"])

vllm_omni/entrypoints/async_omni.py

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM-Omni project
+
 """
 AsyncOmni - Refactored async orchestrator using AsyncOmniEngine.
 
@@ -1421,19 +1424,9 @@ async def reset_mm_cache(self) -> None:
         ``EngineCore.sleep(level>=1)`` already clears the P1 receiver cache.
         Clearing P0 avoids hash-only follow-up requests after that reset.
         """
-        processor = getattr(self, "input_processor", None)
-        if processor is None:
-            processor = getattr(self.engine, "input_processor", None)
-        cache = getattr(processor, "mm_processor_cache", None)
-        if cache is None:
-            logger.debug("[AsyncOmni] reset_mm_cache: no frontend mm_processor_cache")
-            return
-        for name in ("clear", "reset", "clear_cache"):
-            fn = getattr(cache, name, None)
-            if callable(fn):
-                fn()
-                return
-        logger.debug("[AsyncOmni] reset_mm_cache: cache has no clear/reset method")
+        renderer = self.renderer
+        if renderer is not None:
+            await renderer.clear_mm_cache_async()
 
     async def reset_encoder_cache(self) -> None:
         """Reset the encoder cache for all stages.