tipc: make resetting of links non-atomic
In order to facilitate future improvements to the locking structure, we
want to make resetting and establishing of links non-atomic. I.e., the
functions tipc_node_link_up() and tipc_node_link_down() should be called
from outside the node lock context, and grab/release the node lock
themselves. This requires that we can freeze the link state from the
moment it is set to RESETTING or PEER_RESET in one lock context until
it is set to RESET or ESTABLISHING in a later context. The recently
introduced link FSM makes this possible, so we are now ready to introduce
the above change.
This commit implements this.
Tested-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/tipc/msg.h b/net/tipc/msg.h
index 115bb2a..53d98ef 100644
--- a/net/tipc/msg.h
+++ b/net/tipc/msg.h
@@ -916,4 +916,33 @@
return false;
}
+/* tipc_skb_queue_splice_tail - append an skb list to lock protected list
+ * @list: the new list to append. Not lock protected
+ * @head: target list. Lock protected.
+ */
+static inline void tipc_skb_queue_splice_tail(struct sk_buff_head *list,
+ struct sk_buff_head *head)
+{
+ spin_lock_bh(&head->lock);
+ skb_queue_splice_tail(list, head);
+ spin_unlock_bh(&head->lock);
+}
+
+/* tipc_skb_queue_splice_tail_init - merge two lock protected skb lists
+ * @list: the new list to add. Lock protected. Will be reinitialized
+ * @head: target list. Lock protected.
+ */
+static inline void tipc_skb_queue_splice_tail_init(struct sk_buff_head *list,
+ struct sk_buff_head *head)
+{
+ struct sk_buff_head tmp;
+
+ __skb_queue_head_init(&tmp);
+
+ spin_lock_bh(&list->lock);
+ skb_queue_splice_tail_init(list, &tmp);
+ spin_unlock_bh(&list->lock);
+ tipc_skb_queue_splice_tail(&tmp, head);
+}
+
#endif