[Misc] Remove unnecessary `_send_reconfig_message()` in `core_client.py` (#23127)

Signed-off-by: Nick Hill <nhill@redhat.com>

vllm/v1/engine/core_client.py

@@ -1190,21 +1190,6 @@ class DPLBAsyncMPClient(DPAsyncMPClient):
         await self._send_input(EngineCoreRequestType.ABORT, request_ids,
                                engine)
 
-    async def _send_reconfig_message(
-            self, reconfig_request: ReconfigureDistributedRequest,
-            engine: EngineIdentity) -> asyncio.Future:
-        """Send reconfiguration message and return the result future without
-        waiting for completion."""
-        call_id = uuid.uuid1().int >> 64
-        future = asyncio.get_running_loop().create_future()
-        self.utility_results[call_id] = future
-        message = (EngineCoreRequestType.UTILITY.value, *self.encoder.encode(
-            (self.client_index, call_id, "reinitialize_distributed",
-             (reconfig_request, ))))
-        await self._send_input_message(message, engine, reconfig_request)
-        self._ensure_output_queue_task()
-        return future
-
     async def scale_elastic_ep(self, new_data_parallel_size: int) -> None:
         """Scale elastic EP data parallel size"""
         cur_data_parallel_size = len(self.core_engines)
@@ -1214,7 +1199,7 @@ class DPLBAsyncMPClient(DPAsyncMPClient):
             f"different from cur_data_parallel_size {cur_data_parallel_size}")
 
         assert self.vllm_config.parallel_config.data_parallel_backend == \
-            "ray", ("Only ray DP backend supports scaling elastic EP")
+            "ray", "Only ray DP backend supports scaling elastic EP"
 
         scale_up = new_data_parallel_size > cur_data_parallel_size
 
@@ -1246,9 +1231,10 @@ class DPLBAsyncMPClient(DPAsyncMPClient):
                 data_parallel_master_ip,
                 new_data_parallel_master_port=self.vllm_config.parallel_config.
                 data_parallel_master_port)
-            future = await self._send_reconfig_message(reconfig_request,
-                                                       engine)
-            reconfig_futures.append(future)
+            coro = self._call_utility_async("reinitialize_distributed",
+                                            reconfig_request,
+                                            engine=engine)
+            reconfig_futures.append(asyncio.create_task(coro))
 
         logger.info("All reconfigure messages sent, starting engine creation")
 
@@ -1318,9 +1304,10 @@ class DPLBAsyncMPClient(DPAsyncMPClient):
             if cur_dp_rank >= new_data_parallel_size:
                 reconfig_request.new_data_parallel_rank = \
                 ReconfigureRankType.SHUTDOWN_CURRENT_RANK
-            future = await self._send_reconfig_message(reconfig_request,
-                                                       engine)
-            reconfig_futures.append(future)
+            coro = self._call_utility_async("reinitialize_distributed",
+                                            reconfig_request,
+                                            engine=engine)
+            reconfig_futures.append(asyncio.create_task(coro))
 
         for _ in range(new_data_parallel_size, cur_data_parallel_size):
             self.core_engines.pop()