[https://nvbugs/5508267][fix] Proper handling of inactive canceled requests (#9280)

Signed-off-by: thorjohnsen <41591019+thorjohnsen@users.noreply.github.com>

Author: thorjohnsen

tensorrt_llm/_torch/pyexecutor/py_executor.py

@@ -2236,9 +2236,14 @@ def _handle_canceled_requests(self):
         # Remove cancel request in the waiting queue
         self.executor_request_queue.update_waiting_queue()
 
+        # Create set from list of canceled request ids to speed up canceled test
+        canceled_req_ids = set(
+            self.executor_request_queue.get_canceled_req_ids())
+
+        still_pending_canceled_ids = []
         for request in self.active_requests:
             req_id = request.py_request_id if not request.is_child else request.parent_request_id
-            if req_id not in self.executor_request_queue.get_canceled_req_ids():
+            if req_id not in canceled_req_ids:
                 continue
 
             is_cancelled = self._try_cancel_request(request)
@@ -2247,13 +2252,13 @@ def _handle_canceled_requests(self):
                 # to clean up the KV cache resources.
                 request.finish_by_reason(FinishReason.CANCELLED)
                 request.decoding_iter = request.py_decoding_iter
-                self.executor_request_queue.canceled_req_ids.remove(req_id)
+            else:
+                still_pending_canceled_ids.append(req_id)
 
-        if self.enable_attention_dp:
-            # TODO: revisit the cancel logic of attention dp
-            # When enable attention dp, each rank does not have full copy of requests
-            # so we need to remove the cancel requests not in the local rank
-            self.executor_request_queue.clear_canceled_req_ids()
+        # Clear list of requests marked for cancellation and add back those that failed to cancel.
+        self.executor_request_queue.canceled_req_ids.clear()
+        self.executor_request_queue.canceled_req_ids.extend(
+            still_pending_canceled_ids)
 
     @nvtx_range("_enqueue_responses")
     def _enqueue_responses(self, responses: Iterable[Tuple[int, LlmResponse]]):