udp: Neaten and reduce size of compute_score functions

The compute_score functions are a bit difficult to read.

Neaten them a bit to reduce object sizes and make them a
bit more intelligible.

Return early to avoid indentation and avoid unnecessary
initializations.

(allyesconfig, but w/ -O2 and no profiling)

$ size net/ipv[46]/udp.o.*
   text    data     bss     dec     hex filename
  28680    1184      25   29889    74c1 net/ipv4/udp.o.new
  28756    1184      25   29965    750d net/ipv4/udp.o.old
  17600    1010       2   18612    48b4 net/ipv6/udp.o.new
  17632    1010       2   18644    48d4 net/ipv6/udp.o.old
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/udp.c

@@ -336,38 +336,45 @@ int udp_v4_get_port(struct sock *sk, unsigned short snum)
 	return udp_lib_get_port(sk, snum, ipv4_rcv_saddr_equal, hash2_nulladdr);
 }
 
-static inline int compute_score(struct sock *sk, struct net *net, __be32 saddr,
-			 unsigned short hnum,
-			 __be16 sport, __be32 daddr, __be16 dport, int dif)
+static inline int compute_score(struct sock *sk, struct net *net,
+				__be32 saddr, unsigned short hnum, __be16 sport,
+				__be32 daddr, __be16 dport, int dif)
 {
-	int score = -1;
+	int score;
+	struct inet_sock *inet;
 
-	if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
-			!ipv6_only_sock(sk)) {
-		struct inet_sock *inet = inet_sk(sk);
+	if (!net_eq(sock_net(sk), net) ||
+	    udp_sk(sk)->udp_port_hash != hnum ||
+	    ipv6_only_sock(sk))
+		return -1;
+
+	score = (sk->sk_family == PF_INET) ? 2 : 1;
+	inet = inet_sk(sk);
 
-		score = (sk->sk_family == PF_INET ? 2 : 1);
 	if (inet->inet_rcv_saddr) {
 		if (inet->inet_rcv_saddr != daddr)
 			return -1;
 		score += 4;
 	}
+
 	if (inet->inet_daddr) {
 		if (inet->inet_daddr != saddr)
 			return -1;
 		score += 4;
 	}
+
 	if (inet->inet_dport) {
 		if (inet->inet_dport != sport)
 			return -1;
 		score += 4;
 	}
+
 	if (sk->sk_bound_dev_if) {
 		if (sk->sk_bound_dev_if != dif)
 			return -1;
 		score += 4;
 	}
-	}
+
 	return score;
 }
 
@@ -378,33 +385,39 @@ static inline int compute_score2(struct sock *sk, struct net *net,
 				 __be32 saddr, __be16 sport,
 				 __be32 daddr, unsigned int hnum, int dif)
 {
-	int score = -1;
-
-	if (net_eq(sock_net(sk), net) && !ipv6_only_sock(sk)) {
-		struct inet_sock *inet = inet_sk(sk);
+	int score;
+	struct inet_sock *inet;
 
-		if (inet->inet_rcv_saddr != daddr)
+	if (!net_eq(sock_net(sk), net) ||
+	    ipv6_only_sock(sk))
 		return -1;
-		if (inet->inet_num != hnum)
+
+	inet = inet_sk(sk);
+
+	if (inet->inet_rcv_saddr != daddr ||
+	    inet->inet_num != hnum)
 		return -1;
 
-		score = (sk->sk_family == PF_INET ? 2 : 1);
+	score = (sk->sk_family == PF_INET) ? 2 : 1;
+
 	if (inet->inet_daddr) {
 		if (inet->inet_daddr != saddr)
 			return -1;
 		score += 4;
 	}
+
 	if (inet->inet_dport) {
 		if (inet->inet_dport != sport)
 			return -1;
 		score += 4;
 	}
+
 	if (sk->sk_bound_dev_if) {
 		if (sk->sk_bound_dev_if != dif)
 			return -1;
 		score += 4;
 	}
-	}
+
 	return score;
 }
 

net/ipv6/udp.c

@@ -148,72 +148,85 @@ static inline int compute_score(struct sock *sk, struct net *net,
 				const struct in6_addr *daddr, __be16 dport,
 				int dif)
 {
-	int score = -1;
+	int score;
+	struct inet_sock *inet;
 
-	if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
-			sk->sk_family == PF_INET6) {
-		struct inet_sock *inet = inet_sk(sk);
+	if (!net_eq(sock_net(sk), net) ||
+	    udp_sk(sk)->udp_port_hash != hnum ||
+	    sk->sk_family != PF_INET6)
+		return -1;
 
 	score = 0;
+	inet = inet_sk(sk);
+
 	if (inet->inet_dport) {
 		if (inet->inet_dport != sport)
 			return -1;
 		score++;
 	}
+
 	if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
 		if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
 			return -1;
 		score++;
 	}
+
 	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 		if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
 			return -1;
 		score++;
 	}
+
 	if (sk->sk_bound_dev_if) {
 		if (sk->sk_bound_dev_if != dif)
 			return -1;
 		score++;
 	}
-	}
+
 	return score;
 }
 
 #define SCORE2_MAX (1 + 1 + 1)
 static inline int compute_score2(struct sock *sk, struct net *net,
 				 const struct in6_addr *saddr, __be16 sport,
-				const struct in6_addr *daddr, unsigned short hnum,
-				int dif)
+				 const struct in6_addr *daddr,
+				 unsigned short hnum, int dif)
 {
-	int score = -1;
+	int score;
+	struct inet_sock *inet;
 
-	if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
-			sk->sk_family == PF_INET6) {
-		struct inet_sock *inet = inet_sk(sk);
+	if (!net_eq(sock_net(sk), net) ||
+	    udp_sk(sk)->udp_port_hash != hnum ||
+	    sk->sk_family != PF_INET6)
+		return -1;
 
 	if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
 		return -1;
+
 	score = 0;
+	inet = inet_sk(sk);
+
 	if (inet->inet_dport) {
 		if (inet->inet_dport != sport)
 			return -1;
 		score++;
 	}
+
 	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
 		if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
 			return -1;
 		score++;
 	}
+
 	if (sk->sk_bound_dev_if) {
 		if (sk->sk_bound_dev_if != dif)
 			return -1;
 		score++;
 	}
-	}
+
 	return score;
 }
 
-
 /* called with read_rcu_lock() */
 static struct sock *udp6_lib_lookup2(struct net *net,
 		const struct in6_addr *saddr, __be16 sport,