udp: split sk_hash into two u16 hashes
Union sk_hash with two u16 hashes for udp (no extra memory taken)
One 16 bits hash on (local port) value (the previous udp 'hash')
One 16 bits hash on (local address, local port) values, initialized
but not yet used. This second hash is using jenkin hash for better
distribution.
Because the 'port' is xored later, a partial hash is performed
on local address + net_hash_mix(net)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/udp.h b/include/linux/udp.h
index 832361e..5b4b527 100644
--- a/include/linux/udp.h
+++ b/include/linux/udp.h
@@ -55,6 +55,8 @@
struct udp_sock {
/* inet_sock has to be the first member */
struct inet_sock inet;
+#define udp_port_hash inet.sk.__sk_common.skc_u16hashes[0]
+#define udp_portaddr_hash inet.sk.__sk_common.skc_u16hashes[1]
int pending; /* Any pending frames ? */
unsigned int corkflag; /* Cork is required */
__u16 encap_type; /* Is this an Encapsulation socket? */
diff --git a/include/net/sock.h b/include/net/sock.h
index 55de3bd..827366b 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -109,6 +109,7 @@
* @skc_refcnt: reference count
* @skc_tx_queue_mapping: tx queue number for this connection
* @skc_hash: hash value used with various protocol lookup tables
+ * @skc_u16hashes: two u16 hash values used by UDP lookup tables
* @skc_family: network address family
* @skc_state: Connection state
* @skc_reuse: %SO_REUSEADDR setting
@@ -131,7 +132,10 @@
atomic_t skc_refcnt;
int skc_tx_queue_mapping;
- unsigned int skc_hash;
+ union {
+ unsigned int skc_hash;
+ __u16 skc_u16hashes[2];
+ };
unsigned short skc_family;
volatile unsigned char skc_state;
unsigned char skc_reuse;
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index ffc8376..af72de1 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -138,13 +138,14 @@
sk_nulls_for_each(sk2, node, &hslot->head)
if (net_eq(sock_net(sk2), net) &&
sk2 != sk &&
- (bitmap || sk2->sk_hash == num) &&
+ (bitmap || udp_sk(sk2)->udp_port_hash == num) &&
(!sk2->sk_reuse || !sk->sk_reuse) &&
(!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if
|| sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
(*saddr_comp)(sk, sk2)) {
if (bitmap)
- __set_bit(sk2->sk_hash >> log, bitmap);
+ __set_bit(udp_sk(sk2)->udp_port_hash >> log,
+ bitmap);
else
return 1;
}
@@ -215,7 +216,8 @@
}
found:
inet_sk(sk)->inet_num = snum;
- sk->sk_hash = snum;
+ udp_sk(sk)->udp_port_hash = snum;
+ udp_sk(sk)->udp_portaddr_hash ^= snum;
if (sk_unhashed(sk)) {
sk_nulls_add_node_rcu(sk, &hslot->head);
hslot->count++;
@@ -238,8 +240,19 @@
inet1->inet_rcv_saddr == inet2->inet_rcv_saddr));
}
+static unsigned int udp4_portaddr_hash(struct net *net, __be32 saddr,
+ unsigned int port)
+{
+ return jhash_1word(saddr, net_hash_mix(net)) ^ port;
+}
+
int udp_v4_get_port(struct sock *sk, unsigned short snum)
{
+ /* precompute partial secondary hash */
+ udp_sk(sk)->udp_portaddr_hash =
+ udp4_portaddr_hash(sock_net(sk),
+ inet_sk(sk)->inet_rcv_saddr,
+ 0);
return udp_lib_get_port(sk, snum, ipv4_rcv_saddr_equal);
}
@@ -249,7 +262,7 @@
{
int score = -1;
- if (net_eq(sock_net(sk), net) && sk->sk_hash == hnum &&
+ 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);
@@ -360,7 +373,7 @@
struct inet_sock *inet = inet_sk(s);
if (!net_eq(sock_net(s), net) ||
- s->sk_hash != hnum ||
+ udp_sk(s)->udp_port_hash != hnum ||
(inet->inet_daddr && inet->inet_daddr != rmt_addr) ||
(inet->inet_dport != rmt_port && inet->inet_dport) ||
(inet->inet_rcv_saddr &&
@@ -1050,7 +1063,7 @@
if (sk_hashed(sk)) {
struct udp_table *udptable = sk->sk_prot->h.udp_table;
struct udp_hslot *hslot = udp_hashslot(udptable, sock_net(sk),
- sk->sk_hash);
+ udp_sk(sk)->udp_port_hash);
spin_lock_bh(&hslot->lock);
if (sk_nulls_del_node_init_rcu(sk)) {
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 5bc7cdb..1e5fadd 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -81,8 +81,30 @@
return 0;
}
+static unsigned int udp6_portaddr_hash(struct net *net,
+ const struct in6_addr *addr6,
+ unsigned int port)
+{
+ unsigned int hash, mix = net_hash_mix(net);
+
+ if (ipv6_addr_any(addr6))
+ hash = jhash_1word(0, mix);
+ else if (ipv6_addr_type(addr6) == IPV6_ADDR_MAPPED)
+ hash = jhash_1word(addr6->s6_addr32[3], mix);
+ else
+ hash = jhash2(addr6->s6_addr32, 4, mix);
+
+ return hash ^ port;
+}
+
+
int udp_v6_get_port(struct sock *sk, unsigned short snum)
{
+ /* precompute partial secondary hash */
+ udp_sk(sk)->udp_portaddr_hash =
+ udp6_portaddr_hash(sock_net(sk),
+ &inet6_sk(sk)->rcv_saddr,
+ 0);
return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal);
}
@@ -94,7 +116,7 @@
{
int score = -1;
- if (net_eq(sock_net(sk), net) && sk->sk_hash == hnum &&
+ if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
sk->sk_family == PF_INET6) {
struct ipv6_pinfo *np = inet6_sk(sk);
struct inet_sock *inet = inet_sk(sk);
@@ -415,7 +437,8 @@
if (!net_eq(sock_net(s), net))
continue;
- if (s->sk_hash == num && s->sk_family == PF_INET6) {
+ if (udp_sk(s)->udp_port_hash == num &&
+ s->sk_family == PF_INET6) {
struct ipv6_pinfo *np = inet6_sk(s);
if (inet->inet_dport) {
if (inet->inet_dport != rmt_port)