ipv6: Create fast inline ipv6 neigh lookup just like ipv4.

Also, create and use an rt6_bind_neighbour() in net/ipv6/route.c to
consolidate some common logic.

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2011-12-28 15:41:23 -05:00
parent 2c2aba6c56
commit f83c7790dc
2 changed files with 49 additions and 19 deletions

View File

@ -89,6 +89,33 @@ static inline u32 ndisc_hashfn(const void *pkey, const struct net_device *dev, _
(p32[3] * hash_rnd[3]));
}
static inline struct neighbour *__ipv6_neigh_lookup(struct neigh_table *tbl, struct net_device *dev, const void *pkey)
{
struct neigh_hash_table *nht;
const u32 *p32 = pkey;
struct neighbour *n;
u32 hash_val;
rcu_read_lock_bh();
nht = rcu_dereference_bh(tbl->nht);
hash_val = ndisc_hashfn(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
n != NULL;
n = rcu_dereference_bh(n->next)) {
u32 *n32 = (u32 *) n->primary_key;
if (n->dev == dev &&
((n32[0] ^ p32[0]) | (n32[1] ^ p32[1]) |
(n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0) {
if (!atomic_inc_not_zero(&n->refcnt))
n = NULL;
break;
}
}
rcu_read_unlock_bh();
return n;
}
extern int ndisc_init(void);
extern void ndisc_cleanup(void);

View File

@ -123,7 +123,20 @@ static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst, const void *daddr)
{
return __neigh_lookup_errno(&nd_tbl, daddr, dst->dev);
struct neighbour *n = __ipv6_neigh_lookup(&nd_tbl, dst->dev, daddr);
if (n)
return n;
return neigh_create(&nd_tbl, daddr, dst->dev);
}
static int rt6_bind_neighbour(struct rt6_info *rt)
{
struct neighbour *n = ip6_neigh_lookup(&rt->dst, &rt->rt6i_gateway);
if (IS_ERR(n))
return PTR_ERR(n);
dst_set_neighbour(&rt->dst, n);
return 0;
}
static struct dst_ops ip6_dst_ops_template = {
@ -714,7 +727,6 @@ static struct rt6_info *rt6_alloc_cow(const struct rt6_info *ort,
rt = ip6_rt_copy(ort, daddr);
if (rt) {
struct neighbour *neigh;
int attempts = !in_softirq();
if (!(rt->rt6i_flags & RTF_GATEWAY)) {
@ -734,9 +746,7 @@ static struct rt6_info *rt6_alloc_cow(const struct rt6_info *ort,
#endif
retry:
neigh = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway,
rt->rt6i_dev);
if (IS_ERR(neigh)) {
if (rt6_bind_neighbour(rt)) {
struct net *net = dev_net(rt->rt6i_dev);
int saved_rt_min_interval =
net->ipv6.sysctl.ip6_rt_gc_min_interval;
@ -762,8 +772,6 @@ static struct rt6_info *rt6_alloc_cow(const struct rt6_info *ort,
dst_free(&rt->dst);
return NULL;
}
dst_set_neighbour(&rt->dst, neigh);
}
return rt;
@ -1078,7 +1086,7 @@ struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
if (neigh)
neigh_hold(neigh);
else {
neigh = __neigh_lookup_errno(&nd_tbl, &fl6->daddr, dev);
neigh = ip6_neigh_lookup(&rt->dst, &fl6->daddr);
if (IS_ERR(neigh)) {
dst_free(&rt->dst);
return ERR_CAST(neigh);
@ -1389,12 +1397,9 @@ int ip6_route_add(struct fib6_config *cfg)
rt->rt6i_prefsrc.plen = 0;
if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
struct neighbour *n = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev);
if (IS_ERR(n)) {
err = PTR_ERR(n);
err = rt6_bind_neighbour(rt);
if (err)
goto out;
}
dst_set_neighbour(&rt->dst, n);
}
rt->rt6i_flags = cfg->fc_flags;
@ -2057,7 +2062,7 @@ struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
struct net *net = dev_net(idev->dev);
struct rt6_info *rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops,
net->loopback_dev, 0);
struct neighbour *neigh;
int err;
if (!rt) {
if (net_ratelimit())
@ -2079,13 +2084,11 @@ struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
rt->rt6i_flags |= RTF_ANYCAST;
else
rt->rt6i_flags |= RTF_LOCAL;
neigh = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, rt->rt6i_dev);
if (IS_ERR(neigh)) {
err = rt6_bind_neighbour(rt);
if (err) {
dst_free(&rt->dst);
return ERR_CAST(neigh);
return ERR_PTR(err);
}
dst_set_neighbour(&rt->dst, neigh);
rt->rt6i_dst.addr = *addr;
rt->rt6i_dst.plen = 128;