udp: get rid of sk_prot_clear_portaddr_nulls()

Since we no longer use SLAB_DESTROY_BY_RCU for UDP,
we do not need sk_prot_clear_portaddr_nulls() helper.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/net/sock.h

@@ -1242,8 +1242,6 @@ static inline int __sk_prot_rehash(struct sock *sk)
 	return sk->sk_prot->hash(sk);
 }
 
-void sk_prot_clear_portaddr_nulls(struct sock *sk, int size);
-
 /* About 10 seconds */
 #define SOCK_DESTROY_TIME (10*HZ)
 

net/core/sock.c

@@ -1315,24 +1315,6 @@ static void sock_copy(struct sock *nsk, const struct sock *osk)
 #endif
 }
 
-void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
-{
-	unsigned long nulls1, nulls2;
-
-	nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
-	nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
-	if (nulls1 > nulls2)
-		swap(nulls1, nulls2);
-
-	if (nulls1 != 0)
-		memset((char *)sk, 0, nulls1);
-	memset((char *)sk + nulls1 + sizeof(void *), 0,
-	       nulls2 - nulls1 - sizeof(void *));
-	memset((char *)sk + nulls2 + sizeof(void *), 0,
-	       size - nulls2 - sizeof(void *));
-}
-EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
-
 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
 		int family)
 {

net/ipv4/udp.c

@@ -2237,7 +2237,6 @@ struct proto udp_prot = {
 	.compat_setsockopt = compat_udp_setsockopt,
 	.compat_getsockopt = compat_udp_getsockopt,
 #endif
-	.clear_sk	   = sk_prot_clear_portaddr_nulls,
 	.diag_destroy	   = udp_abort,
 };
 EXPORT_SYMBOL(udp_prot);

net/ipv4/udplite.c

@@ -61,7 +61,6 @@ struct proto 	udplite_prot = {
 	.compat_setsockopt = compat_udp_setsockopt,
 	.compat_getsockopt = compat_udp_getsockopt,
 #endif
-	.clear_sk	   = sk_prot_clear_portaddr_nulls,
 };
 EXPORT_SYMBOL(udplite_prot);
 

net/ipv6/udplite.c

@@ -56,7 +56,6 @@ struct proto udplitev6_prot = {
 	.compat_setsockopt = compat_udpv6_setsockopt,
 	.compat_getsockopt = compat_udpv6_getsockopt,
 #endif
-	.clear_sk	   = sk_prot_clear_portaddr_nulls,
 };
 
 static struct inet_protosw udplite6_protosw = {