diff options
author | stephen hemminger <shemminger@vyatta.com> | 2010-03-17 20:31:12 +0000 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2010-03-20 15:44:35 -0700 |
commit | 3a88a81d89c20be312b3b219b185bbdde24b8fb8 (patch) | |
tree | 2610b2b8b47deb4e4d5db0968af21911306442b3 /net | |
parent | 5c578aedcb21d79eeb4e9cf04ca5b276ac82614c (diff) | |
download | blackbird-op-linux-3a88a81d89c20be312b3b219b185bbdde24b8fb8.tar.gz blackbird-op-linux-3a88a81d89c20be312b3b219b185bbdde24b8fb8.zip |
ipv6: user better hash for addrconf
The existing hash function has a couple of issues:
* it is hardwired to 16 for IN6_ADDR_HSIZE
* limited to 256 and callers using int
* use jhash2 rather than some old BSD algorithm
No need for random seed since this is local only (based on assigned
addresses) table.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r-- | net/ipv6/addrconf.c | 25 |
1 files changed, 8 insertions, 17 deletions
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 7ffd5eeab967..1e5e41fe92bc 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -573,23 +573,14 @@ ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp) *ifap = ifp; } -/* - * Hash function taken from net_alias.c - */ -static u8 ipv6_addr_hash(const struct in6_addr *addr) +static u32 ipv6_addr_hash(const struct in6_addr *addr) { - __u32 word; - /* * We perform the hash function over the last 64 bits of the address * This will include the IEEE address token on links that support it. */ - - word = (__force u32)(addr->s6_addr32[2] ^ addr->s6_addr32[3]); - word ^= (word >> 16); - word ^= (word >> 8); - - return ((word ^ (word >> 4)) & 0x0f); + return jhash_2words(addr->s6_addr32[2], addr->s6_addr32[3], 0) + & (IN6_ADDR_HSIZE - 1); } /* On success it returns ifp with increased reference count */ @@ -600,7 +591,7 @@ ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen, { struct inet6_ifaddr *ifa = NULL; struct rt6_info *rt; - int hash; + unsigned int hash; int err = 0; int addr_type = ipv6_addr_type(addr); @@ -1277,7 +1268,7 @@ int ipv6_chk_addr(struct net *net, struct in6_addr *addr, { struct inet6_ifaddr *ifp = NULL; struct hlist_node *node; - u8 hash = ipv6_addr_hash(addr); + unsigned int hash = ipv6_addr_hash(addr); rcu_read_lock_bh(); hlist_for_each_entry_rcu(ifp, node, &inet6_addr_lst[hash], addr_lst) { @@ -1302,7 +1293,7 @@ int ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr, { struct inet6_ifaddr *ifp; struct hlist_node *node; - u8 hash = ipv6_addr_hash(addr); + unsigned int hash = ipv6_addr_hash(addr); hlist_for_each_entry(ifp, node, &inet6_addr_lst[hash], addr_lst) { if (!net_eq(dev_net(ifp->idev->dev), net)) @@ -1345,7 +1336,7 @@ struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *add { struct inet6_ifaddr *ifp = NULL; struct hlist_node *node; - u8 hash = ipv6_addr_hash(addr); + unsigned int hash = ipv6_addr_hash(addr); rcu_read_lock_bh(); hlist_for_each_entry_rcu(ifp, node, &inet6_addr_lst[hash], addr_lst) { @@ -3083,7 +3074,7 @@ int ipv6_chk_home_addr(struct net *net, struct in6_addr *addr) int ret = 0; struct inet6_ifaddr *ifp = NULL; struct hlist_node *n; - u8 hash = ipv6_addr_hash(addr); + unsigned int hash = ipv6_addr_hash(addr); rcu_read_lock_bh(); hlist_for_each_entry_rcu(ifp, n, &inet6_addr_lst[hash], addr_lst) { |