From 0b4419162aa6c4204843f3a13b48d9ab821d3167 Mon Sep 17 00:00:00 2001 From: Pavel Emelyanov Date: Mon, 16 Jun 2008 17:14:11 -0700 Subject: netns: introduce the net_hash_mix "salt" for hashes There are many possible ways to add this "salt", thus I made this patch to be the last in the series to change it if required. Currently I propose to use the struct net pointer itself as this salt, but since this pointer is most often cache-line aligned, shift this right to eliminate the bits, that are most often zeroed. After this, simply add this mix to prepared hashfn-s. For CONFIG_NET_NS=n case this salt is 0 and no changes in hashfn appear. Signed-off-by: Pavel Emelyanov Signed-off-by: David S. Miller --- include/net/inet_hashtables.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'include/net/inet_hashtables.h') diff --git a/include/net/inet_hashtables.h b/include/net/inet_hashtables.h index 26336cdcdc1..bb619d80f2e 100644 --- a/include/net/inet_hashtables.h +++ b/include/net/inet_hashtables.h @@ -29,6 +29,7 @@ #include #include #include +#include #include #include @@ -204,7 +205,7 @@ extern void inet_bind_bucket_destroy(struct kmem_cache *cachep, static inline int inet_bhashfn(struct net *net, const __u16 lport, const int bhash_size) { - return lport & (bhash_size - 1); + return (lport + net_hash_mix(net)) & (bhash_size - 1); } extern void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb, @@ -213,7 +214,7 @@ extern void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb, /* These can have wildcards, don't try too hard. */ static inline int inet_lhashfn(struct net *net, const unsigned short num) { - return num & (INET_LHTABLE_SIZE - 1); + return (num + net_hash_mix(net)) & (INET_LHTABLE_SIZE - 1); } static inline int inet_sk_listen_hashfn(const struct sock *sk) -- cgit v1.2.3-70-g09d2