/* Ok, let's try this, I give up, we do need a local binding
         * TCP hash as well as the others for fast bind/connect.
         */
+       struct kmem_cache               *bind_bucket_cachep;
        struct inet_bind_hashbucket     *bhash;
-
        unsigned int                    bhash_size;
-       /* 4 bytes hole on 64 bit */
 
-       struct kmem_cache               *bind_bucket_cachep;
+       /* The 2nd listener table hashed by local port and address */
+       unsigned int                    lhash2_mask;
+       struct inet_listen_hashbucket   *lhash2;
 
        /* All the above members are written once at bootup and
         * never written again _or_ are predominantly read-access.
         * Now align to a new cache line as all the following members
         * might be often dirty.
         */
-       /* All sockets in TCP_LISTEN state will be in here.  This is the only
-        * table where wildcard'd TCP sockets can exist.  Hash function here
-        * is just local port number.
+       /* All sockets in TCP_LISTEN state will be in listening_hash.
+        * This is the only table where wildcard'd TCP sockets can
+        * exist.  listening_hash is only hashed by local port number.
+        * If lhash2 is initialized, the same socket will also be hashed
+        * to lhash2 by port and address.
         */
        struct inet_listen_hashbucket   listening_hash[INET_LHTABLE_SIZE]
                                        ____cacheline_aligned_in_smp;
 };
 
+#define inet_lhash2_for_each_icsk_rcu(__icsk, list) \
+       hlist_for_each_entry_rcu(__icsk, list, icsk_listen_portaddr_node)
+
+static inline struct inet_listen_hashbucket *
+inet_lhash2_bucket(struct inet_hashinfo *h, u32 hash)
+{
+       return &h->lhash2[hash & h->lhash2_mask];
+}
+
 static inline struct inet_ehash_bucket *inet_ehash_bucket(
        struct inet_hashinfo *hashinfo,
        unsigned int hash)
 void inet_put_port(struct sock *sk);
 
 void inet_hashinfo_init(struct inet_hashinfo *h);
+void inet_hashinfo2_init(struct inet_hashinfo *h, const char *name,
+                        unsigned long numentries, int scale,
+                        unsigned long low_limit,
+                        unsigned long high_limit);
 
 bool inet_ehash_insert(struct sock *sk, struct sock *osk);
 bool inet_ehash_nolisten(struct sock *sk, struct sock *osk);
 
 #include <linux/slab.h>
 #include <linux/wait.h>
 #include <linux/vmalloc.h>
+#include <linux/bootmem.h>
 
 #include <net/addrconf.h>
 #include <net/inet_connection_sock.h>
 }
 EXPORT_SYMBOL_GPL(__inet_inherit_port);
 
+static struct inet_listen_hashbucket *
+inet_lhash2_bucket_sk(struct inet_hashinfo *h, struct sock *sk)
+{
+       u32 hash;
+
+#if IS_ENABLED(CONFIG_IPV6)
+       if (sk->sk_family == AF_INET6)
+               hash = ipv6_portaddr_hash(sock_net(sk),
+                                         &sk->sk_v6_rcv_saddr,
+                                         inet_sk(sk)->inet_num);
+       else
+#endif
+               hash = ipv4_portaddr_hash(sock_net(sk),
+                                         inet_sk(sk)->inet_rcv_saddr,
+                                         inet_sk(sk)->inet_num);
+       return inet_lhash2_bucket(h, hash);
+}
+
+static void inet_hash2(struct inet_hashinfo *h, struct sock *sk)
+{
+       struct inet_listen_hashbucket *ilb2;
+
+       if (!h->lhash2)
+               return;
+
+       ilb2 = inet_lhash2_bucket_sk(h, sk);
+
+       spin_lock(&ilb2->lock);
+       if (sk->sk_reuseport && sk->sk_family == AF_INET6)
+               hlist_add_tail_rcu(&inet_csk(sk)->icsk_listen_portaddr_node,
+                                  &ilb2->head);
+       else
+               hlist_add_head_rcu(&inet_csk(sk)->icsk_listen_portaddr_node,
+                                  &ilb2->head);
+       ilb2->count++;
+       spin_unlock(&ilb2->lock);
+}
+
+static void inet_unhash2(struct inet_hashinfo *h, struct sock *sk)
+{
+       struct inet_listen_hashbucket *ilb2;
+
+       if (!h->lhash2 ||
+           WARN_ON_ONCE(hlist_unhashed(&inet_csk(sk)->icsk_listen_portaddr_node)))
+               return;
+
+       ilb2 = inet_lhash2_bucket_sk(h, sk);
+
+       spin_lock(&ilb2->lock);
+       hlist_del_init_rcu(&inet_csk(sk)->icsk_listen_portaddr_node);
+       ilb2->count--;
+       spin_unlock(&ilb2->lock);
+}
+
 static inline int compute_score(struct sock *sk, struct net *net,
                                const unsigned short hnum, const __be32 daddr,
                                const int dif, const int sdif, bool exact_dif)
  */
 
 /* called with rcu_read_lock() : No refcount taken on the socket */
+static struct sock *inet_lhash2_lookup(struct net *net,
+                               struct inet_listen_hashbucket *ilb2,
+                               struct sk_buff *skb, int doff,
+                               const __be32 saddr, __be16 sport,
+                               const __be32 daddr, const unsigned short hnum,
+                               const int dif, const int sdif)
+{
+       bool exact_dif = inet_exact_dif_match(net, skb);
+       struct inet_connection_sock *icsk;
+       struct sock *sk, *result = NULL;
+       int score, hiscore = 0;
+       u32 phash = 0;
+
+       inet_lhash2_for_each_icsk_rcu(icsk, &ilb2->head) {
+               sk = (struct sock *)icsk;
+               score = compute_score(sk, net, hnum, daddr,
+                                     dif, sdif, exact_dif);
+               if (score > hiscore) {
+                       if (sk->sk_reuseport) {
+                               phash = inet_ehashfn(net, daddr, hnum,
+                                                    saddr, sport);
+                               result = reuseport_select_sock(sk, phash,
+                                                              skb, doff);
+                               if (result)
+                                       return result;
+                       }
+                       result = sk;
+                       hiscore = score;
+               }
+       }
+
+       return result;
+}
+
 struct sock *__inet_lookup_listener(struct net *net,
                                    struct inet_hashinfo *hashinfo,
                                    struct sk_buff *skb, int doff,
        unsigned int hash = inet_lhashfn(net, hnum);
        struct inet_listen_hashbucket *ilb = &hashinfo->listening_hash[hash];
        bool exact_dif = inet_exact_dif_match(net, skb);
+       struct inet_listen_hashbucket *ilb2;
        struct sock *sk, *result = NULL;
        int score, hiscore = 0;
+       unsigned int hash2;
        u32 phash = 0;
 
+       if (ilb->count <= 10 || !hashinfo->lhash2)
+               goto port_lookup;
+
+       /* Too many sk in the ilb bucket (which is hashed by port alone).
+        * Try lhash2 (which is hashed by port and addr) instead.
+        */
+
+       hash2 = ipv4_portaddr_hash(net, daddr, hnum);
+       ilb2 = inet_lhash2_bucket(hashinfo, hash2);
+       if (ilb2->count > ilb->count)
+               goto port_lookup;
+
+       result = inet_lhash2_lookup(net, ilb2, skb, doff,
+                                   saddr, sport, daddr, hnum,
+                                   dif, sdif);
+       if (result)
+               return result;
+
+       /* Lookup lhash2 with INADDR_ANY */
+
+       hash2 = ipv4_portaddr_hash(net, htonl(INADDR_ANY), hnum);
+       ilb2 = inet_lhash2_bucket(hashinfo, hash2);
+       if (ilb2->count > ilb->count)
+               goto port_lookup;
+
+       return inet_lhash2_lookup(net, ilb2, skb, doff,
+                                 saddr, sport, daddr, hnum,
+                                 dif, sdif);
+
+port_lookup:
        sk_for_each_rcu(sk, &ilb->head) {
                score = compute_score(sk, net, hnum, daddr,
                                      dif, sdif, exact_dif);
                hlist_add_tail_rcu(&sk->sk_node, &ilb->head);
        else
                hlist_add_head_rcu(&sk->sk_node, &ilb->head);
+       inet_hash2(hashinfo, sk);
        ilb->count++;
        sock_set_flag(sk, SOCK_RCU_FREE);
        sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
        struct inet_listen_hashbucket *ilb;
        spinlock_t *lock;
        bool listener = false;
-       int done;
 
        if (sk_unhashed(sk))
                return;
                lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
        }
        spin_lock_bh(lock);
+       if (sk_unhashed(sk))
+               goto unlock;
+
        if (rcu_access_pointer(sk->sk_reuseport_cb))
                reuseport_detach_sock(sk);
-       if (listener)
-               done = __sk_del_node_init(sk);
-       else
-               done = __sk_nulls_del_node_init_rcu(sk);
-       if (done) {
-               if (listener)
-                       ilb->count--;
-               sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
+       if (listener) {
+               inet_unhash2(hashinfo, sk);
+                __sk_del_node_init(sk);
+                ilb->count--;
+       } else {
+               __sk_nulls_del_node_init_rcu(sk);
        }
+       sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
+unlock:
        spin_unlock_bh(lock);
 }
 EXPORT_SYMBOL_GPL(inet_unhash);
                INIT_HLIST_HEAD(&h->listening_hash[i].head);
                h->listening_hash[i].count = 0;
        }
+
+       h->lhash2 = NULL;
 }
 EXPORT_SYMBOL_GPL(inet_hashinfo_init);
 
+void __init inet_hashinfo2_init(struct inet_hashinfo *h, const char *name,
+                               unsigned long numentries, int scale,
+                               unsigned long low_limit,
+                               unsigned long high_limit)
+{
+       unsigned int i;
+
+       h->lhash2 = alloc_large_system_hash(name,
+                                           sizeof(*h->lhash2),
+                                           numentries,
+                                           scale,
+                                           0,
+                                           NULL,
+                                           &h->lhash2_mask,
+                                           low_limit,
+                                           high_limit);
+
+       for (i = 0; i <= h->lhash2_mask; i++) {
+               spin_lock_init(&h->lhash2[i].lock);
+               INIT_HLIST_HEAD(&h->lhash2[i].head);
+               h->lhash2[i].count = 0;
+       }
+}
+
 int inet_ehash_locks_alloc(struct inet_hashinfo *hashinfo)
 {
        unsigned int locksz = sizeof(spinlock_t);
 
 }
 
 /* called with rcu_read_lock() */
+static struct sock *inet6_lhash2_lookup(struct net *net,
+               struct inet_listen_hashbucket *ilb2,
+               struct sk_buff *skb, int doff,
+               const struct in6_addr *saddr,
+               const __be16 sport, const struct in6_addr *daddr,
+               const unsigned short hnum, const int dif, const int sdif)
+{
+       bool exact_dif = inet6_exact_dif_match(net, skb);
+       struct inet_connection_sock *icsk;
+       struct sock *sk, *result = NULL;
+       int score, hiscore = 0;
+       u32 phash = 0;
+
+       inet_lhash2_for_each_icsk_rcu(icsk, &ilb2->head) {
+               sk = (struct sock *)icsk;
+               score = compute_score(sk, net, hnum, daddr, dif, sdif,
+                                     exact_dif);
+               if (score > hiscore) {
+                       if (sk->sk_reuseport) {
+                               phash = inet6_ehashfn(net, daddr, hnum,
+                                                     saddr, sport);
+                               result = reuseport_select_sock(sk, phash,
+                                                              skb, doff);
+                               if (result)
+                                       return result;
+                       }
+                       result = sk;
+                       hiscore = score;
+               }
+       }
+
+       return result;
+}
+
 struct sock *inet6_lookup_listener(struct net *net,
                struct inet_hashinfo *hashinfo,
                struct sk_buff *skb, int doff,
        unsigned int hash = inet_lhashfn(net, hnum);
        struct inet_listen_hashbucket *ilb = &hashinfo->listening_hash[hash];
        bool exact_dif = inet6_exact_dif_match(net, skb);
+       struct inet_listen_hashbucket *ilb2;
        struct sock *sk, *result = NULL;
        int score, hiscore = 0;
+       unsigned int hash2;
        u32 phash = 0;
 
+       if (ilb->count <= 10 || !hashinfo->lhash2)
+               goto port_lookup;
+
+       /* Too many sk in the ilb bucket (which is hashed by port alone).
+        * Try lhash2 (which is hashed by port and addr) instead.
+        */
+
+       hash2 = ipv6_portaddr_hash(net, daddr, hnum);
+       ilb2 = inet_lhash2_bucket(hashinfo, hash2);
+       if (ilb2->count > ilb->count)
+               goto port_lookup;
+
+       result = inet6_lhash2_lookup(net, ilb2, skb, doff,
+                                    saddr, sport, daddr, hnum,
+                                    dif, sdif);
+       if (result)
+               return result;
+
+       /* Lookup lhash2 with in6addr_any */
+
+       hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
+       ilb2 = inet_lhash2_bucket(hashinfo, hash2);
+       if (ilb2->count > ilb->count)
+               goto port_lookup;
+
+       return inet6_lhash2_lookup(net, ilb2, skb, doff,
+                                  saddr, sport, daddr, hnum,
+                                  dif, sdif);
+
+port_lookup:
        sk_for_each(sk, &ilb->head) {
                score = compute_score(sk, net, hnum, daddr, dif, sdif, exact_dif);
                if (score > hiscore) {