tipc: make media xmit call outside node spinlock context

Currently, message sending is performed through a deep call chain,
where the node spinlock is grabbed and held during a significant
part of the transmission time. This is clearly detrimental to
overall throughput performance; it would be better if we could send
the message after the spinlock has been released.

In this commit, we do instead let the call revert on the stack after
the buffer chain has been added to the transmission queue, whereafter
clones of the buffers are transmitted to the device layer outside the
spinlock scope.

As a further step in our effort to separate the roles of the node
and link entities we also move the function tipc_link_xmit() to
node.c, and rename it to tipc_node_xmit().

Reviewed-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>

1 files changed, 2 insertions, 4 deletions

diff --git a/net/tipc/link.h b/net/tipc/link.h
index 9c71d9e42e93..7add2b90361d 100644
--- a/net/tipc/link.h
+++ b/net/tipc/link.h
@@ -223,12 +223,10 @@ void tipc_link_purge_queues(struct tipc_link *l_ptr);
 void tipc_link_purge_backlog(struct tipc_link *l);
 void tipc_link_reset_all(struct tipc_node *node);
 void tipc_link_reset(struct tipc_link *l_ptr);
-int tipc_link_xmit_skb(struct net *net, struct sk_buff *skb, u32 dest,
-                       u32 selector);
-int tipc_link_xmit(struct net *net, struct sk_buff_head *list, u32 dest,
-                   u32 selector);
 int __tipc_link_xmit(struct net *net, struct tipc_link *link,
                      struct sk_buff_head *list);
+int tipc_link_xmit(struct tipc_link *link,      struct sk_buff_head *list,
+                   struct sk_buff_head *xmitq);
 void tipc_link_proto_xmit(struct tipc_link *l_ptr, u32 msg_typ, int prob,
                           u32 gap, u32 tolerance, u32 priority);
 void tipc_link_push_packets(struct tipc_link *l_ptr);