io_uring: refactor io_sq_thread()

Move needs_sched declaration into the block where it's used, so it's
harder to misuse/wrongfully reuse.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/e4a07db1353ee38b924dd1b45394cf8e746130b4.1624543113.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

fs/io_uring.c

@@ -6876,7 +6876,7 @@ static int io_sq_thread(void *data)
 
 	mutex_lock(&sqd->lock);
 	while (1) {
-		bool cap_entries, sqt_spin, needs_sched;
+		bool cap_entries, sqt_spin = false;
 
 		if (io_sqd_events_pending(sqd) || signal_pending(current)) {
 			if (io_sqd_handle_event(sqd))
@@ -6885,7 +6885,6 @@ static int io_sq_thread(void *data)
 			continue;
 		}
 
-		sqt_spin = false;
 		cap_entries = !list_is_singular(&sqd->ctx_list);
 		list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
 			int ret = __io_sq_thread(ctx, cap_entries);
@@ -6904,7 +6903,8 @@ static int io_sq_thread(void *data)
 
 		prepare_to_wait(&sqd->wait, &wait, TASK_INTERRUPTIBLE);
 		if (!io_sqd_events_pending(sqd) && !io_run_task_work()) {
-			needs_sched = true;
+			bool needs_sched = true;
+
 			list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
 				io_ring_set_wakeup_flag(ctx);