Merge tag 'nfs-for-6.1-1' of git://git.linux-nfs.org/projects/anna/linux-nfs

[platform/kernel/linux-rpi.git] / net / sunrpc / sched.c

diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index 46cbf15..be587a3 100644 (file)
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -65,6 +65,13 @@ gfp_t rpc_task_gfp_mask(void)
 }
 EXPORT_SYMBOL_GPL(rpc_task_gfp_mask);
 
+bool rpc_task_set_rpc_status(struct rpc_task *task, int rpc_status)
+{
+       if (cmpxchg(&task->tk_rpc_status, 0, rpc_status) == 0)
+               return true;
+       return false;
+}
+
 unsigned long
 rpc_task_timeout(const struct rpc_task *task)
 {
@@ -853,12 +860,25 @@ void rpc_signal_task(struct rpc_task *task)
        if (!RPC_IS_ACTIVATED(task))
                return;
 
+       if (!rpc_task_set_rpc_status(task, -ERESTARTSYS))
+               return;
        trace_rpc_task_signalled(task, task->tk_action);
        set_bit(RPC_TASK_SIGNALLED, &task->tk_runstate);
        smp_mb__after_atomic();
        queue = READ_ONCE(task->tk_waitqueue);
        if (queue)
-               rpc_wake_up_queued_task_set_status(queue, task, -ERESTARTSYS);
+               rpc_wake_up_queued_task(queue, task);
+}
+
+void rpc_task_try_cancel(struct rpc_task *task, int error)
+{
+       struct rpc_wait_queue *queue;
+
+       if (!rpc_task_set_rpc_status(task, error))
+               return;
+       queue = READ_ONCE(task->tk_waitqueue);
+       if (queue)
+               rpc_wake_up_queued_task(queue, task);
 }
 
 void rpc_exit(struct rpc_task *task, int status)
@@ -905,10 +925,16 @@ static void __rpc_execute(struct rpc_task *task)
                 * Perform the next FSM step or a pending callback.
                 *
                 * tk_action may be NULL if the task has been killed.
-                * In particular, note that rpc_killall_tasks may
-                * do this at any time, so beware when dereferencing.
                 */
                do_action = task->tk_action;
+               /* Tasks with an RPC error status should exit */
+               if (do_action != rpc_exit_task &&
+                   (status = READ_ONCE(task->tk_rpc_status)) != 0) {
+                       task->tk_status = status;
+                       if (do_action != NULL)
+                               do_action = rpc_exit_task;
+               }
+               /* Callbacks override all actions */
                if (task->tk_callback) {
                        do_action = task->tk_callback;
                        task->tk_callback = NULL;
@@ -931,14 +957,6 @@ static void __rpc_execute(struct rpc_task *task)
                }
 
                /*
-                * Signalled tasks should exit rather than sleep.
-                */
-               if (RPC_SIGNALLED(task)) {
-                       task->tk_rpc_status = -ERESTARTSYS;
-                       rpc_exit(task, -ERESTARTSYS);
-               }
-
-               /*
                 * The queue->lock protects against races with
                 * rpc_make_runnable().
                 *
@@ -953,6 +971,12 @@ static void __rpc_execute(struct rpc_task *task)
                        spin_unlock(&queue->lock);
                        continue;
                }
+               /* Wake up any task that has an exit status */
+               if (READ_ONCE(task->tk_rpc_status) != 0) {
+                       rpc_wake_up_task_queue_locked(queue, task);
+                       spin_unlock(&queue->lock);
+                       continue;
+               }
                rpc_clear_running(task);
                spin_unlock(&queue->lock);
                if (task_is_async)
@@ -970,10 +994,7 @@ static void __rpc_execute(struct rpc_task *task)
                         * clean up after sleeping on some queue, we don't
                         * break the loop here, but go around once more.
                         */
-                       trace_rpc_task_signalled(task, task->tk_action);
-                       set_bit(RPC_TASK_SIGNALLED, &task->tk_runstate);
-                       task->tk_rpc_status = -ERESTARTSYS;
-                       rpc_exit(task, -ERESTARTSYS);
+                       rpc_signal_task(task);
                }
                trace_rpc_task_sync_wake(task, task->tk_action);
        }