io-wq: simplify worker exiting

io_worker_handle_work() already takes care of the empty list case and
releases spinlock, so get rid of ugly conditional unlocking and
unconditionally call handle_work()
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/7521e485677f381036676943e876a0afecc23017.1623634181.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

fs/io-wq.c

@@ -565,10 +565,7 @@ static int io_wqe_worker(void *data)
 
 	if (test_bit(IO_WQ_BIT_EXIT, &wq->state)) {
 		raw_spin_lock_irq(&wqe->lock);
-		if (!wq_list_empty(&wqe->work_list))
 		io_worker_handle_work(worker);
-		else
-			raw_spin_unlock_irq(&wqe->lock);
 	}
 
 	io_worker_exit(worker);