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, 4 insertions, 0 deletions

diff --git a/net/tipc/node.h b/net/tipc/node.h
index 74f278adada3..86b7c740cf84 100644
--- a/net/tipc/node.h
+++ b/net/tipc/node.h
@@ -160,6 +160,10 @@ bool tipc_node_is_up(struct tipc_node *n);
 int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 node,
 			   char *linkname, size_t len);
 void tipc_node_unlock(struct tipc_node *node);
+int tipc_node_xmit(struct net *net, struct sk_buff_head *list, u32 dnode,
+		   int selector);
+int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dest,
+		       u32 selector);
 int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port);
 void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port);