inet: rename some inet_sock fields

In order to have better cache layouts of struct sock (separate zones
for rx/tx paths), we need this preliminary patch.

Goal is to transfert fields used at lookup time in the first
read-mostly cache line (inside struct sock_common) and move sk_refcnt
to a separate cache line (only written by rx path)

This patch adds inet_ prefix to daddr, rcv_saddr, dport, num, saddr,
sport and id fields. This allows a future patch to define these
fields as macros, like sk_refcnt, without name clashes.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/tcp.c

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index cf13726..206a291 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1998,7 +1998,7 @@
 	__skb_queue_purge(&sk->sk_async_wait_queue);
 #endif
 
-	inet->dport = 0;
+	inet->inet_dport = 0;
 
 	if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
 		inet_reset_saddr(sk);
@@ -2022,7 +2022,7 @@
 	memset(&tp->rx_opt, 0, sizeof(tp->rx_opt));
 	__sk_dst_reset(sk);
 
-	WARN_ON(inet->num && !icsk->icsk_bind_hash);
+	WARN_ON(inet->inet_num && !icsk->icsk_bind_hash);
 
 	sk->sk_error_report(sk);
 	return err;