tipc: remove port_lock

In previous commits we have reduced usage of port_lock to a minimum,
and complemented it with usage of bh_lock_sock() at the remaining
locations. The purpose has been to remove this lock altogether, since
it largely duplicates the role of bh_lock_sock. We are now ready to do
this.

However, we still need to protect the BH callers from inadvertent
release of the socket while they hold a reference to it. We do this by
replacing port_lock by a combination of a rw-lock protecting the
reference table as such, and updating the socket reference counter while
the socket is referenced from BH. This technique is more standard and
comprehensible than the previous approach, and turns out to have a
positive effect on overall performance.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 0 insertions, 20 deletions

diff --git a/net/tipc/port.h b/net/tipc/port.h
index 33e52fe50e10..38bf8cb3df1a 100644
--- a/net/tipc/port.h
+++ b/net/tipc/port.h
@@ -37,7 +37,6 @@
 #ifndef _TIPC_PORT_H
 #define _TIPC_PORT_H
 
-#include "ref.h"
 #include "net.h"
 #include "msg.h"
 #include "node_subscr.h"
@@ -65,7 +64,6 @@
  * @timer_ref:
  */
 struct tipc_port {
-	spinlock_t *lock;
 	int connected;
 	u32 conn_type;
 	u32 conn_instance;
@@ -98,24 +96,6 @@ int tipc_port_peer_msg(struct tipc_port *p_ptr, struct tipc_msg *msg);
 
 void tipc_port_reinit(void);
 
-/**
- * tipc_port_lock - lock port instance referred to and return its pointer
- */
-static inline struct tipc_sock *tipc_port_lock(u32 ref)
-{
-	return (struct tipc_sock *)tipc_ref_lock(ref);
-}
-
-/**
- * tipc_port_unlock - unlock a port instance
- *
- * Can use pointer instead of tipc_ref_unlock() since port is already locked.
- */
-static inline void tipc_port_unlock(struct tipc_port *p_ptr)
-{
-	spin_unlock_bh(p_ptr->lock);
-}
-
 static inline u32 tipc_port_peernode(struct tipc_port *p_ptr)
 {
 	return msg_destnode(&p_ptr->phdr);