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, 15 insertions, 18 deletions

diff --git a/net/tipc/msg.c b/net/tipc/msg.c
index da67c8d3edc6..940d74197b8c 100644
--- a/net/tipc/msg.c
+++ b/net/tipc/msg.c
@@ -70,25 +70,23 @@ struct sk_buff *tipc_buf_acquire(u32 size)
         return skb;
 }
 
-void tipc_msg_init(struct net *net, struct tipc_msg *m, u32 user, u32 type,
-                   u32 hsize, u32 destnode)
+void tipc_msg_init(u32 own_node, struct tipc_msg *m, u32 user, u32 type,
+                   u32 hsize, u32 dnode)
 {
-        struct tipc_net *tn = net_generic(net, tipc_net_id);
-
         memset(m, 0, hsize);
         msg_set_version(m);
         msg_set_user(m, user);
         msg_set_hdr_sz(m, hsize);
         msg_set_size(m, hsize);
-        msg_set_prevnode(m, tn->own_addr);
+        msg_set_prevnode(m, own_node);
         msg_set_type(m, type);
         if (hsize > SHORT_H_SIZE) {
-                msg_set_orignode(m, tn->own_addr);
-                msg_set_destnode(m, destnode);
+                msg_set_orignode(m, own_node);
+                msg_set_destnode(m, dnode);
         }
 }
 
-struct sk_buff *tipc_msg_create(struct net *net, uint user, uint type,
+struct sk_buff *tipc_msg_create(uint user, uint type,
                                 uint hdr_sz, uint data_sz, u32 dnode,
                                 u32 onode, u32 dport, u32 oport, int errcode)
 {
@@ -100,9 +98,8 @@ struct sk_buff *tipc_msg_create(struct net *net, uint user, uint type,
                 return NULL;
 
         msg = buf_msg(buf);
-        tipc_msg_init(net, msg, user, type, hdr_sz, dnode);
+        tipc_msg_init(onode, msg, user, type, hdr_sz, dnode);
         msg_set_size(msg, hdr_sz + data_sz);
-        msg_set_prevnode(msg, onode);
         msg_set_origport(msg, oport);
         msg_set_destport(msg, dport);
         msg_set_errcode(msg, errcode);
@@ -195,7 +192,7 @@ err:
  *
  * Returns message data size or errno: -ENOMEM, -EFAULT
  */
-int tipc_msg_build(struct net *net, struct tipc_msg *mhdr, struct msghdr *m,
+int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m,
                    int offset, int dsz, int pktmax, struct sk_buff_head *list)
 {
         int mhsz = msg_hdr_sz(mhdr);
@@ -227,8 +224,8 @@ int tipc_msg_build(struct net *net, struct tipc_msg *mhdr, struct msghdr *m,
         }
 
         /* Prepare reusable fragment header */
-        tipc_msg_init(net, &pkthdr, MSG_FRAGMENTER, FIRST_FRAGMENT, INT_H_SIZE,
-                      msg_destnode(mhdr));
+        tipc_msg_init(msg_prevnode(mhdr), &pkthdr, MSG_FRAGMENTER,
+                      FIRST_FRAGMENT, INT_H_SIZE, msg_destnode(mhdr));
         msg_set_size(&pkthdr, pktmax);
         msg_set_fragm_no(&pkthdr, pktno);
 
@@ -338,7 +335,7 @@ bool tipc_msg_bundle(struct sk_buff_head *list, struct sk_buff *skb, u32 mtu)
  * Replaces buffer if successful
  * Returns true if success, otherwise false
  */
-bool tipc_msg_make_bundle(struct net *net, struct sk_buff_head *list,
+bool tipc_msg_make_bundle(struct sk_buff_head *list,
                           struct sk_buff *skb, u32 mtu, u32 dnode)
 {
         struct sk_buff *bskb;
@@ -362,7 +359,8 @@ bool tipc_msg_make_bundle(struct net *net, struct sk_buff_head *list,
 
         skb_trim(bskb, INT_H_SIZE);
         bmsg = buf_msg(bskb);
-        tipc_msg_init(net, bmsg, MSG_BUNDLER, 0, INT_H_SIZE, dnode);
+        tipc_msg_init(msg_prevnode(msg), bmsg, MSG_BUNDLER, 0,
+                      INT_H_SIZE, dnode);
         msg_set_seqno(bmsg, msg_seqno(msg));
         msg_set_ack(bmsg, msg_ack(msg));
         msg_set_bcast_ack(bmsg, msg_bcast_ack(msg));
@@ -379,10 +377,9 @@ bool tipc_msg_make_bundle(struct net *net, struct sk_buff_head *list,
  * Consumes buffer if failure
  * Returns true if success, otherwise false
  */
-bool tipc_msg_reverse(struct net *net, struct sk_buff *buf, u32 *dnode,
+bool tipc_msg_reverse(u32 own_addr,  struct sk_buff *buf, u32 *dnode,
                       int err)
 {
-        struct tipc_net *tn = net_generic(net, tipc_net_id);
         struct tipc_msg *msg = buf_msg(buf);
         uint imp = msg_importance(msg);
         struct tipc_msg ohdr;
@@ -402,7 +399,7 @@ bool tipc_msg_reverse(struct net *net, struct sk_buff *buf, u32 *dnode,
         msg_set_errcode(msg, err);
         msg_set_origport(msg, msg_destport(&ohdr));
         msg_set_destport(msg, msg_origport(&ohdr));
-        msg_set_prevnode(msg, tn->own_addr);
+        msg_set_prevnode(msg, own_addr);
         if (!msg_short(msg)) {
                 msg_set_orignode(msg, msg_destnode(&ohdr));
                 msg_set_destnode(msg, msg_orignode(&ohdr));