From ac3175fe7a5788d40b067b76c27f2943cd0be2d7 Mon Sep 17 00:00:00 2001 From: =?utf8?q?YOSHIFUJI=20Hideaki=20/=20=E5=90=89=E8=97=A4=E8=8B=B1?= =?utf8?q?=E6=98=8E?= Date: Thu, 17 Jan 2013 12:53:22 +0000 Subject: [PATCH] ndisc: Introduce __ipv6_neigh_lookup_noref(). This function, which looks up neighbour entry for an IPv6 address without touching refcnt, will be used for patches to remove dependency on rt->n (neighbour entry in rt6_info). Signed-off-by: YOSHIFUJI Hideaki Signed-off-by: David S. Miller --- include/net/ndisc.h | 22 +++++++++++++++------- 1 file changed, 15 insertions(+), 7 deletions(-) diff --git a/include/net/ndisc.h b/include/net/ndisc.h index bbc938edf41b..ec48f42db5ed 100644 --- a/include/net/ndisc.h +++ b/include/net/ndisc.h @@ -148,14 +148,13 @@ 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 net_device *dev, const void *pkey) +static inline struct neighbour *__ipv6_neigh_lookup_noref(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(nd_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]); @@ -164,12 +163,21 @@ static inline struct neighbour *__ipv6_neigh_lookup(struct net_device *dev, cons 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; - } + (n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0) + return n; } + + return NULL; +} + +static inline struct neighbour *__ipv6_neigh_lookup(struct net_device *dev, const void *pkey) +{ + struct neighbour *n; + + rcu_read_lock_bh(); + n = __ipv6_neigh_lookup_noref(dev, pkey); + if (n && !atomic_inc_not_zero(&n->refcnt)) + n = NULL; rcu_read_unlock_bh(); return n; -- 2.30.2