net: tipc: fix stall during bclink wakeup procedure

[karo-tx-linux.git] / net / tipc / bcast.c

diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c
index 8b010c976b2f7c8eba5f6fe1cadb516b4e0f7269..41042de3ae9bcfad4504e0bcbb29d3bea4512bb5 100644 (file)
--- a/net/tipc/bcast.c
+++ b/net/tipc/bcast.c
@@ -169,6 +169,30 @@ static void bclink_retransmit_pkt(struct tipc_net *tn, u32 after, u32 to)
        }
 }
 
+/**
+ * bclink_prepare_wakeup - prepare users for wakeup after congestion
+ * @bcl: broadcast link
+ * @resultq: queue for users which can be woken up
+ * Move a number of waiting users, as permitted by available space in
+ * the send queue, from link wait queue to specified queue for wakeup
+ */
+static void bclink_prepare_wakeup(struct tipc_link *bcl, struct sk_buff_head *resultq)
+{
+       int pnd[TIPC_SYSTEM_IMPORTANCE + 1] = {0,};
+       int imp, lim;
+       struct sk_buff *skb, *tmp;
+
+       skb_queue_walk_safe(&bcl->wakeupq, skb, tmp) {
+               imp = TIPC_SKB_CB(skb)->chain_imp;
+               lim = bcl->window + bcl->backlog[imp].limit;
+               pnd[imp] += TIPC_SKB_CB(skb)->chain_sz;
+               if ((pnd[imp] + bcl->backlog[imp].len) >= lim)
+                       continue;
+               skb_unlink(skb, &bcl->wakeupq);
+               skb_queue_tail(resultq, skb);
+       }
+}
+
 /**
  * tipc_bclink_wakeup_users - wake up pending users
  *
@@ -177,8 +201,12 @@ static void bclink_retransmit_pkt(struct tipc_net *tn, u32 after, u32 to)
 void tipc_bclink_wakeup_users(struct net *net)
 {
        struct tipc_net *tn = net_generic(net, tipc_net_id);
+       struct tipc_link *bcl = tn->bcl;
+       struct sk_buff_head resultq;
 
-       tipc_sk_rcv(net, &tn->bclink->link.wakeupq);
+       skb_queue_head_init(&resultq);
+       bclink_prepare_wakeup(bcl, &resultq);
+       tipc_sk_rcv(net, &resultq);
 }
 
 /**