[NET]: prot_inuse cleanups and optimizations

1) Cleanups (all functions are prefixed by sock_prot_inuse)

sock_prot_inc_use(prot) -> sock_prot_inuse_add(prot,-1)
sock_prot_dec_use(prot) -> sock_prot_inuse_add(prot,-1)
sock_prot_inuse()       -> sock_prot_inuse_get()

New functions :

sock_prot_inuse_init() and sock_prot_inuse_free() to abstract pcounter use.

2) if CONFIG_PROC_FS=n, we can zap 'inuse' member from "struct proto",
since nobody wants to read the inuse value.

This saves 1372 bytes on i386/SMP and some cpu cycles.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
index 0765d8b..a66a7d8 100644
--- a/net/ipv6/inet6_hashtables.c
+++ b/net/ipv6/inet6_hashtables.c
@@ -43,7 +43,7 @@
 	}
 
 	__sk_add_node(sk, list);
-	sock_prot_inc_use(sk->sk_prot);
+	sock_prot_inuse_add(sk->sk_prot, 1);
 	write_unlock(lock);
 }
 EXPORT_SYMBOL(__inet6_hash);
@@ -216,7 +216,7 @@
 	BUG_TRAP(sk_unhashed(sk));
 	__sk_add_node(sk, &head->chain);
 	sk->sk_hash = hash;
-	sock_prot_inc_use(sk->sk_prot);
+	sock_prot_inuse_add(sk->sk_prot, 1);
 	write_unlock(lock);
 
 	if (twp != NULL) {
diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index 20fece4..bf2a686 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -268,8 +268,8 @@
 				struct inet_connection_sock *icsk = inet_csk(sk);
 
 				local_bh_disable();
-				sock_prot_dec_use(sk->sk_prot);
-				sock_prot_inc_use(&tcp_prot);
+				sock_prot_inuse_add(sk->sk_prot, -1);
+				sock_prot_inuse_add(&tcp_prot, 1);
 				local_bh_enable();
 				sk->sk_prot = &tcp_prot;
 				icsk->icsk_af_ops = &ipv4_specific;
@@ -282,8 +282,8 @@
 				if (sk->sk_protocol == IPPROTO_UDPLITE)
 					prot = &udplite_prot;
 				local_bh_disable();
-				sock_prot_dec_use(sk->sk_prot);
-				sock_prot_inc_use(prot);
+				sock_prot_inuse_add(sk->sk_prot, -1);
+				sock_prot_inuse_add(prot, 1);
 				local_bh_enable();
 				sk->sk_prot = prot;
 				sk->sk_socket->ops = &inet_dgram_ops;
diff --git a/net/ipv6/proc.c b/net/ipv6/proc.c
index 41e9980..571d95a 100644
--- a/net/ipv6/proc.c
+++ b/net/ipv6/proc.c
@@ -36,13 +36,13 @@
 static int sockstat6_seq_show(struct seq_file *seq, void *v)
 {
 	seq_printf(seq, "TCP6: inuse %d\n",
-		       sock_prot_inuse(&tcpv6_prot));
+		       sock_prot_inuse_get(&tcpv6_prot));
 	seq_printf(seq, "UDP6: inuse %d\n",
-		       sock_prot_inuse(&udpv6_prot));
+		       sock_prot_inuse_get(&udpv6_prot));
 	seq_printf(seq, "UDPLITE6: inuse %d\n",
-			sock_prot_inuse(&udplitev6_prot));
+			sock_prot_inuse_get(&udplitev6_prot));
 	seq_printf(seq, "RAW6: inuse %d\n",
-		       sock_prot_inuse(&rawv6_prot));
+		       sock_prot_inuse_get(&rawv6_prot));
 	seq_printf(seq, "FRAG6: inuse %d memory %d\n",
 		       ip6_frag_nqueues(), ip6_frag_mem());
 	return 0;