From fdcc8aa953a1123a289791dd192090651036d593 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sun, 8 Nov 2009 10:17:05 +0000 Subject: [PATCH] udp: add a counter into udp_hslot Adds a counter in udp_hslot to keep an accurate count of sockets present in chain. This will permit to upcoming UDP lookup algo to chose the shortest chain when secondary hash is added. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/udp.h | 8 ++++++++ net/ipv4/udp.c | 3 +++ 2 files changed, 11 insertions(+) diff --git a/include/net/udp.h b/include/net/udp.h index 22aa2e7eb1d..9167281e47d 100644 --- a/include/net/udp.h +++ b/include/net/udp.h @@ -50,8 +50,16 @@ struct udp_skb_cb { }; #define UDP_SKB_CB(__skb) ((struct udp_skb_cb *)((__skb)->cb)) +/** + * struct udp_hslot - UDP hash slot + * + * @head: head of list of sockets + * @count: number of sockets in 'head' list + * @lock: spinlock protecting changes to head/count + */ struct udp_hslot { struct hlist_nulls_head head; + int count; spinlock_t lock; } __attribute__((aligned(2 * sizeof(long)))); diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index d5e75e97651..ffc837643a0 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -218,6 +218,7 @@ found: sk->sk_hash = snum; if (sk_unhashed(sk)) { sk_nulls_add_node_rcu(sk, &hslot->head); + hslot->count++; sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); } error = 0; @@ -1053,6 +1054,7 @@ void udp_lib_unhash(struct sock *sk) spin_lock_bh(&hslot->lock); if (sk_nulls_del_node_init_rcu(sk)) { + hslot->count--; inet_sk(sk)->inet_num = 0; sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); } @@ -1862,6 +1864,7 @@ void __init udp_table_init(struct udp_table *table, const char *name) } for (i = 0; i <= table->mask; i++) { INIT_HLIST_NULLS_HEAD(&table->hash[i].head, i); + table->hash[i].count = 0; spin_lock_init(&table->hash[i].lock); } } -- 2.41.0