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: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2023-01-27 09:50:31 -07:00
parent fcc926bb85
commit f586800854
1 changed files with 7 additions and 1 deletions

View File

@ -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;