Merge branch 'freezer'

[~andy/linux] / net / sunrpc / sched.c

diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index 8dcfadcef5d3d217c6ce29014dad3a318584633d..77d251e0259315eeef4acd4de50def4382bba5e1 100644 (file)
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -324,11 +324,17 @@ EXPORT_SYMBOL_GPL(__rpc_wait_for_completion_task);
  * Note: If the task is ASYNC, and is being made runnable after sitting on an
  * rpc_wait_queue, this must be called with the queue spinlock held to protect
  * the wait queue operation.
+ * Note the ordering of rpc_test_and_set_running() and rpc_clear_queued(),
+ * which is needed to ensure that __rpc_execute() doesn't loop (due to the
+ * lockless RPC_IS_QUEUED() test) before we've had a chance to test
+ * the RPC_TASK_RUNNING flag.
  */
 static void rpc_make_runnable(struct rpc_task *task)
 {
+       bool need_wakeup = !rpc_test_and_set_running(task);
+
        rpc_clear_queued(task);
-       if (rpc_test_and_set_running(task))
+       if (!need_wakeup)
                return;
        if (RPC_IS_ASYNC(task)) {
                INIT_WORK(&task->u.tk_work, rpc_async_schedule);