diff options
| author | Eric Dumazet <edumazet@google.com> | 2012-07-18 08:11:12 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-07-18 11:28:46 -0700 |
| commit | ddbe503203855939946430e39bae58de11b70b69 (patch) | |
| tree | 1605a8d3b14a92819eb8ed47ae5a84c1b66e12f8 /net/ipv6/addrconf.c | |
| parent | dc9059512c09d09b99de6cd3a8bc842507934cbb (diff) | |
| download | linux-ddbe503203855939946430e39bae58de11b70b69.tar.bz2 | |
ipv6: add ipv6_addr_hash() helper
Introduce ipv6_addr_hash() helper doing a XOR on all bits
of an IPv6 address, with an optimized x86_64 version.
Use it in flow dissector, as suggested by Andrew McGregor,
to reduce hash collision probabilities in fq_codel (and other
users of flow dissector)
Use it in ip6_tunnel.c and use more bit shuffling, as suggested
by David Laight, as existing hash was ignoring most of them.
Use it in sunrpc and use more bit shuffling, using hash_32().
Use it in net/ipv6/addrconf.c, using hash_32() as well.
As a cleanup, use it in net/ipv4/tcp_metrics.c
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrew McGregor <andrewmcgr@gmail.com>
Cc: Dave Taht <dave.taht@gmail.com>
Cc: Tom Herbert <therbert@google.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6/addrconf.c')
| -rw-r--r-- | net/ipv6/addrconf.c | 21 |
1 files changed, 8 insertions, 13 deletions
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 8f6411c97189..79181819a24f 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -63,6 +63,7 @@ #include <linux/delay.h> #include <linux/notifier.h> #include <linux/string.h> +#include <linux/hash.h> #include <net/net_namespace.h> #include <net/sock.h> @@ -579,15 +580,9 @@ ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp) list_add_tail(&ifp->if_list, p); } -static u32 ipv6_addr_hash(const struct in6_addr *addr) +static u32 inet6_addr_hash(const struct in6_addr *addr) { - /* - * 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. - */ - return jhash_2words((__force u32)addr->s6_addr32[2], - (__force u32)addr->s6_addr32[3], 0) - & (IN6_ADDR_HSIZE - 1); + return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT); } /* On success it returns ifp with increased reference count */ @@ -662,7 +657,7 @@ ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen, in6_ifa_hold(ifa); /* Add to big hash table */ - hash = ipv6_addr_hash(addr); + hash = inet6_addr_hash(addr); hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]); spin_unlock(&addrconf_hash_lock); @@ -1270,7 +1265,7 @@ int ipv6_chk_addr(struct net *net, const struct in6_addr *addr, { struct inet6_ifaddr *ifp; struct hlist_node *node; - unsigned int hash = ipv6_addr_hash(addr); + unsigned int hash = inet6_addr_hash(addr); rcu_read_lock_bh(); hlist_for_each_entry_rcu(ifp, node, &inet6_addr_lst[hash], addr_lst) { @@ -1293,7 +1288,7 @@ EXPORT_SYMBOL(ipv6_chk_addr); static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr, struct net_device *dev) { - unsigned int hash = ipv6_addr_hash(addr); + unsigned int hash = inet6_addr_hash(addr); struct inet6_ifaddr *ifp; struct hlist_node *node; @@ -1336,7 +1331,7 @@ struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *add struct net_device *dev, int strict) { struct inet6_ifaddr *ifp, *result = NULL; - unsigned int hash = ipv6_addr_hash(addr); + unsigned int hash = inet6_addr_hash(addr); struct hlist_node *node; rcu_read_lock_bh(); @@ -3223,7 +3218,7 @@ int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr) int ret = 0; struct inet6_ifaddr *ifp = NULL; struct hlist_node *n; - unsigned int hash = ipv6_addr_hash(addr); + unsigned int hash = inet6_addr_hash(addr); rcu_read_lock_bh(); hlist_for_each_entry_rcu_bh(ifp, n, &inet6_addr_lst[hash], addr_lst) { |