io-wq: Remove duplicate code in io_workqueue_create()

While task_work_add() in io_workqueue_create() is true,
then duplicate code is executed:

  -> clear_bit_unlock(0, &worker->create_state);
  -> io_worker_release(worker);
  -> atomic_dec(&acct->nr_running);
  -> io_worker_ref_put(wq);
  -> return false;

  -> clear_bit_unlock(0, &worker->create_state); // back to io_workqueue_create()
  -> io_worker_release(worker);
  -> kfree(worker);

The io_worker_release() and clear_bit_unlock() are executed twice.

Fixes: 3146cba99aa2 ("io-wq: make worker creation resilient against signals")
Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
Link: https://lore.kernel.org/r/20210911085847.34849-1-cuibixuan@huawei.com
Reviwed-by: Hao Xu <haoxu@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io-wq.c b/fs/io-wq.c
index 5bf8aa8..811299a 100644 (file)
--- a/fs/io-wq.c
+++ b/fs/io-wq.c
@@ -323,8 +323,10 @@ static bool io_queue_worker_create(struct io_worker *worker,
 
        init_task_work(&worker->create_work, func);
        worker->create_index = acct->index;
-       if (!task_work_add(wq->task, &worker->create_work, TWA_SIGNAL))
+       if (!task_work_add(wq->task, &worker->create_work, TWA_SIGNAL)) {
+               clear_bit_unlock(0, &worker->create_state);
                return true;
+       }
        clear_bit_unlock(0, &worker->create_state);
 fail_release:
        io_worker_release(worker);
@@ -716,11 +718,8 @@ static void io_workqueue_create(struct work_struct *work)
        struct io_worker *worker = container_of(work, struct io_worker, work);
        struct io_wqe_acct *acct = io_wqe_get_acct(worker);
 
-       if (!io_queue_worker_create(worker, acct, create_worker_cont)) {
-               clear_bit_unlock(0, &worker->create_state);
-               io_worker_release(worker);
+       if (!io_queue_worker_create(worker, acct, create_worker_cont))
                kfree(worker);
-       }
 }
 
 static bool create_io_worker(struct io_wq *wq, struct io_wqe *wqe, int index)