tipc: reduce usage of context info in socket and link

The most common usage of namespace information is when we fetch the
own node addess from the net structure. This leads to a lot of
passing around of a parameter of type 'struct net *' between
functions just to make them able to obtain this address.

However, in many cases this is unnecessary. The own node address
is readily available as a member of both struct tipc_sock and
tipc_link, and can be fetched from there instead.
The fact that the vast majority of functions in socket.c and link.c
anyway are maintaining a pointer to their respective base structures
makes this option even more compelling.

In this commit, we introduce the inline functions tsk_own_node()
and link_own_node() to make it easy for functions to fetch the node
address from those structs instead of having to pass along and
dereference the namespace struct.

In particular, we make calls to the msg_xx() functions in msg.{h,c}
context independent by directly passing them the own node address
as parameter when needed. Those functions should be regarded as
leaves in the code dependency tree, and it is hence desirable to
keep them namspace unaware.

Apart from a potential positive effect on cache behavior, these
changes make it easier to introduce the changes that will follow
later in this series.

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, 36 insertions, 31 deletions

diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index caa4d663fd9..b384e658dfe 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -177,6 +177,11 @@ static const struct nla_policy tipc_nl_sock_policy[TIPC_NLA_SOCK_MAX + 1] = {
  *   - port reference
  */
 
+static u32 tsk_own_node(struct tipc_sock *tsk)
+{
+	return msg_prevnode(&tsk->phdr);
+}
+
 static u32 tsk_peer_node(struct tipc_sock *tsk)
 {
 	return msg_destnode(&tsk->phdr);
@@ -249,11 +254,11 @@ static void tsk_rej_rx_queue(struct sock *sk)
 {
 	struct sk_buff *skb;
 	u32 dnode;
-	struct net *net = sock_net(sk);
+	u32 own_node = tsk_own_node(tipc_sk(sk));
 
 	while ((skb = __skb_dequeue(&sk->sk_receive_queue))) {
-		if (tipc_msg_reverse(net, skb, &dnode, TIPC_ERR_NO_PORT))
-			tipc_link_xmit_skb(net, skb, dnode, 0);
+		if (tipc_msg_reverse(own_node, skb, &dnode, TIPC_ERR_NO_PORT))
+			tipc_link_xmit_skb(sock_net(sk), skb, dnode, 0);
 	}
 }
 
@@ -305,6 +310,7 @@ static bool tsk_peer_msg(struct tipc_sock *tsk, struct tipc_msg *msg)
 static int tipc_sk_create(struct net *net, struct socket *sock,
 			  int protocol, int kern)
 {
+	struct tipc_net *tn;
 	const struct proto_ops *ops;
 	socket_state state;
 	struct sock *sk;
@@ -346,7 +352,8 @@ static int tipc_sk_create(struct net *net, struct socket *sock,
 	tsk->max_pkt = MAX_PKT_DEFAULT;
 	INIT_LIST_HEAD(&tsk->publications);
 	msg = &tsk->phdr;
-	tipc_msg_init(net, msg, TIPC_LOW_IMPORTANCE, TIPC_NAMED_MSG,
+	tn = net_generic(sock_net(sk), tipc_net_id);
+	tipc_msg_init(tn->own_addr, msg, TIPC_LOW_IMPORTANCE, TIPC_NAMED_MSG,
 		      NAMED_H_SIZE, 0);
 
 	/* Finish initializing socket data structures */
@@ -471,7 +478,6 @@ static int tipc_release(struct socket *sock)
 {
 	struct sock *sk = sock->sk;
 	struct net *net;
-	struct tipc_net *tn;
 	struct tipc_sock *tsk;
 	struct sk_buff *skb;
 	u32 dnode, probing_state;
@@ -484,8 +490,6 @@ static int tipc_release(struct socket *sock)
 		return 0;
 
 	net = sock_net(sk);
-	tn = net_generic(net, tipc_net_id);
-
 	tsk = tipc_sk(sk);
 	lock_sock(sk);
 
@@ -507,7 +511,7 @@ static int tipc_release(struct socket *sock)
 				tsk->connected = 0;
 				tipc_node_remove_conn(net, dnode, tsk->portid);
 			}
-			if (tipc_msg_reverse(net, skb, &dnode,
+			if (tipc_msg_reverse(tsk_own_node(tsk), skb, &dnode,
 					     TIPC_ERR_NO_PORT))
 				tipc_link_xmit_skb(net, skb, dnode, 0);
 		}
@@ -520,9 +524,9 @@ static int tipc_release(struct socket *sock)
 		sock_put(sk);
 	tipc_sk_remove(tsk);
 	if (tsk->connected) {
-		skb = tipc_msg_create(net, TIPC_CRITICAL_IMPORTANCE,
+		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE,
 				      TIPC_CONN_MSG, SHORT_H_SIZE, 0, dnode,
-				      tn->own_addr, tsk_peer_port(tsk),
+				      tsk_own_node(tsk), tsk_peer_port(tsk),
 				      tsk->portid, TIPC_ERR_NO_PORT);
 		if (skb)
 			tipc_link_xmit_skb(net, skb, dnode, tsk->portid);
@@ -730,8 +734,9 @@ static int tipc_sendmcast(struct  socket *sock, struct tipc_name_seq *seq,
 			  struct msghdr *msg, size_t dsz, long timeo)
 {
 	struct sock *sk = sock->sk;
+	struct tipc_sock *tsk = tipc_sk(sk);
 	struct net *net = sock_net(sk);
-	struct tipc_msg *mhdr = &tipc_sk(sk)->phdr;
+	struct tipc_msg *mhdr = &tsk->phdr;
 	struct sk_buff_head head;
 	struct iov_iter save = msg->msg_iter;
 	uint mtu;
@@ -749,7 +754,7 @@ static int tipc_sendmcast(struct  socket *sock, struct tipc_name_seq *seq,
 new_mtu:
 	mtu = tipc_bclink_get_mtu();
 	__skb_queue_head_init(&head);
-	rc = tipc_msg_build(net, mhdr, msg, 0, dsz, mtu, &head);
+	rc = tipc_msg_build(mhdr, msg, 0, dsz, mtu, &head);
 	if (unlikely(rc < 0))
 		return rc;
 
@@ -836,7 +841,7 @@ static int tipc_sk_proto_rcv(struct tipc_sock *tsk, u32 *dnode,
 		if (conn_cong)
 			tsk->sk.sk_write_space(&tsk->sk);
 	} else if (msg_type(msg) == CONN_PROBE) {
-		if (!tipc_msg_reverse(sock_net(&tsk->sk), buf, dnode, TIPC_OK))
+		if (!tipc_msg_reverse(tsk_own_node(tsk), buf, dnode, TIPC_OK))
 			return TIPC_OK;
 		msg_set_type(msg, CONN_PROBE_REPLY);
 		return TIPC_FWD_MSG;
@@ -971,7 +976,7 @@ static int tipc_sendmsg(struct kiocb *iocb, struct socket *sock,
 new_mtu:
 	mtu = tipc_node_get_mtu(net, dnode, tsk->portid);
 	__skb_queue_head_init(&head);
-	rc = tipc_msg_build(net, mhdr, m, 0, dsz, mtu, &head);
+	rc = tipc_msg_build(mhdr, m, 0, dsz, mtu, &head);
 	if (rc < 0)
 		goto exit;
 
@@ -1090,7 +1095,7 @@ next:
 	mtu = tsk->max_pkt;
 	send = min_t(uint, dsz - sent, TIPC_MAX_USER_MSG_SIZE);
 	__skb_queue_head_init(&head);
-	rc = tipc_msg_build(net, mhdr, m, sent, send, mtu, &head);
+	rc = tipc_msg_build(mhdr, m, sent, send, mtu, &head);
 	if (unlikely(rc < 0))
 		goto exit;
 	do {
@@ -1263,7 +1268,6 @@ static int tipc_sk_anc_data_recv(struct msghdr *m, struct tipc_msg *msg,
 static void tipc_sk_send_ack(struct tipc_sock *tsk, uint ack)
 {
 	struct net *net = sock_net(&tsk->sk);
-	struct tipc_net *tn = net_generic(net, tipc_net_id);
 	struct sk_buff *skb = NULL;
 	struct tipc_msg *msg;
 	u32 peer_port = tsk_peer_port(tsk);
@@ -1271,9 +1275,9 @@ static void tipc_sk_send_ack(struct tipc_sock *tsk, uint ack)
 
 	if (!tsk->connected)
 		return;
-	skb = tipc_msg_create(net, CONN_MANAGER, CONN_ACK, INT_H_SIZE, 0,
-			      dnode, tn->own_addr, peer_port, tsk->portid,
-			      TIPC_OK);
+	skb = tipc_msg_create(CONN_MANAGER, CONN_ACK, INT_H_SIZE, 0,
+			      dnode, tsk_own_node(tsk), peer_port,
+			      tsk->portid, TIPC_OK);
 	if (!skb)
 		return;
 	msg = buf_msg(skb);
@@ -1756,7 +1760,7 @@ static int tipc_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 		return 0;
 	}
 
-	if ((rc < 0) && !tipc_msg_reverse(net, skb, &onode, -rc))
+	if ((rc < 0) && !tipc_msg_reverse(tsk_own_node(tsk), skb, &onode, -rc))
 		return 0;
 
 	tipc_link_xmit_skb(net, skb, onode, 0);
@@ -1773,6 +1777,7 @@ static int tipc_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 int tipc_sk_rcv(struct net *net, struct sk_buff *skb)
 {
 	struct tipc_sock *tsk;
+	struct tipc_net *tn;
 	struct sock *sk;
 	u32 dport = msg_destport(buf_msg(skb));
 	int rc = TIPC_OK;
@@ -1804,7 +1809,8 @@ int tipc_sk_rcv(struct net *net, struct sk_buff *skb)
 	if (likely(!rc))
 		return 0;
 exit:
-	if ((rc < 0) && !tipc_msg_reverse(net, skb, &dnode, -rc))
+	tn = net_generic(net, tipc_net_id);
+	if ((rc < 0) && !tipc_msg_reverse(tn->own_addr, skb, &dnode, -rc))
 		return -EHOSTUNREACH;
 
 	tipc_link_xmit_skb(net, skb, dnode, 0);
@@ -2065,7 +2071,6 @@ static int tipc_shutdown(struct socket *sock, int how)
 {
 	struct sock *sk = sock->sk;
 	struct net *net = sock_net(sk);
-	struct tipc_net *tn = net_generic(net, tipc_net_id);
 	struct tipc_sock *tsk = tipc_sk(sk);
 	struct sk_buff *skb;
 	u32 dnode;
@@ -2088,16 +2093,17 @@ restart:
 				kfree_skb(skb);
 				goto restart;
 			}
-			if (tipc_msg_reverse(net, skb, &dnode,
+			if (tipc_msg_reverse(tsk_own_node(tsk), skb, &dnode,
 					     TIPC_CONN_SHUTDOWN))
 				tipc_link_xmit_skb(net, skb, dnode,
 						   tsk->portid);
 			tipc_node_remove_conn(net, dnode, tsk->portid);
 		} else {
 			dnode = tsk_peer_node(tsk);
-			skb = tipc_msg_create(net, TIPC_CRITICAL_IMPORTANCE,
+
+			skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE,
 					      TIPC_CONN_MSG, SHORT_H_SIZE,
-					      0, dnode, tn->own_addr,
+					      0, dnode, tsk_own_node(tsk),
 					      tsk_peer_port(tsk),
 					      tsk->portid, TIPC_CONN_SHUTDOWN);
 			tipc_link_xmit_skb(net, skb, dnode, tsk->portid);
@@ -2129,10 +2135,9 @@ static void tipc_sk_timeout(unsigned long data)
 {
 	struct tipc_sock *tsk = (struct tipc_sock *)data;
 	struct sock *sk = &tsk->sk;
-	struct net *net = sock_net(sk);
-	struct tipc_net *tn = net_generic(net, tipc_net_id);
 	struct sk_buff *skb = NULL;
 	u32 peer_port, peer_node;
+	u32 own_node = tsk_own_node(tsk);
 
 	bh_lock_sock(sk);
 	if (!tsk->connected) {
@@ -2144,13 +2149,13 @@ static void tipc_sk_timeout(unsigned long data)
 
 	if (tsk->probing_state == TIPC_CONN_PROBING) {
 		/* Previous probe not answered -> self abort */
-		skb = tipc_msg_create(net, TIPC_CRITICAL_IMPORTANCE,
+		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE,
 				      TIPC_CONN_MSG, SHORT_H_SIZE, 0,
-				      tn->own_addr, peer_node, tsk->portid,
+				      own_node, peer_node, tsk->portid,
 				      peer_port, TIPC_ERR_NO_PORT);
 	} else {
-		skb = tipc_msg_create(net, CONN_MANAGER, CONN_PROBE, INT_H_SIZE,
-				      0, peer_node, tn->own_addr,
+		skb = tipc_msg_create(CONN_MANAGER, CONN_PROBE,
+				      INT_H_SIZE, 0, peer_node, own_node,
 				      peer_port, tsk->portid, TIPC_OK);
 		tsk->probing_state = TIPC_CONN_PROBING;
 		sk_reset_timer(sk, &sk->sk_timer, jiffies + tsk->probing_intv);