Commit f5868008 authored by Jens Axboe's avatar Jens Axboe
Browse files

io_uring: add reschedule point to handle_tw_list() 



If CONFIG_PREEMPT_NONE is set and the task_work chains are long, we
could be running into issues blocking others for too long. Add a
reschedule check in handle_tw_list(), and flush the ctx if we need to
reschedule.

Cc: stable@vger.kernel.org # 5.10+
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent fcc926bb

io_uring/io_uring.c

+7 −1
Original line number Diff line number Diff line
@@ -1179,10 +1179,16 @@ static unsigned int handle_tw_list(struct llist_node *node, 
			/* if not contended, grab and improve batching */

			*locked = mutex_trylock(&(*ctx)->uring_lock);

			percpu_ref_get(&(*ctx)->refs);

		}

		} else if (!*locked)

			*locked = mutex_trylock(&(*ctx)->uring_lock);

		req->io_task_work.func(req, locked);

		node = next;

		count++;

		if (unlikely(need_resched())) {

			ctx_flush_and_put(*ctx, locked);

			*ctx = NULL;

			cond_resched();

		}

	}



	return count;