From 60395a20ffd74166ea373ea91418d6f98fa7fdfb Mon Sep 17 00:00:00 2001 From: Eric W. Biederman Date: Tue, 3 Mar 2015 17:10:44 -0600 Subject: neigh: Factor out ___neigh_lookup_noref While looking at the mpls code I found myself writing yet another version of neigh_lookup_noref. We currently have __ipv4_lookup_noref and __ipv6_lookup_noref. So to make my work a little easier and to make it a smidge easier to verify/maintain the mpls code in the future I stopped and wrote ___neigh_lookup_noref. Then I rewote __ipv4_lookup_noref and __ipv6_lookup_noref in terms of this new function. I tested my new version by verifying that the same code is generated in ip_finish_output2 and ip6_finish_output2 where these functions are inlined. To get to ___neigh_lookup_noref I added a new neighbour cache table function key_eq. So that the static size of the key would be available. I also added __neigh_lookup_noref for people who want to to lookup a neighbour table entry quickly but don't know which neibhgour table they are going to look up. Signed-off-by: "Eric W. Biederman" Signed-off-by: David S. Miller --- include/net/neighbour.h | 52 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) (limited to 'include/net/neighbour.h') diff --git a/include/net/neighbour.h b/include/net/neighbour.h index 9f912e4d4232..14e3f017966b 100644 --- a/include/net/neighbour.h +++ b/include/net/neighbour.h @@ -197,6 +197,7 @@ struct neigh_table { __u32 (*hash)(const void *pkey, const struct net_device *dev, __u32 *hash_rnd); + bool (*key_eq)(const struct neighbour *, const void *pkey); int (*constructor)(struct neighbour *); int (*pconstructor)(struct pneigh_entry *); void (*pdestructor)(struct pneigh_entry *); @@ -247,6 +248,57 @@ static inline void *neighbour_priv(const struct neighbour *n) #define NEIGH_UPDATE_F_ISROUTER 0x40000000 #define NEIGH_UPDATE_F_ADMIN 0x80000000 + +static inline bool neigh_key_eq16(const struct neighbour *n, const void *pkey) +{ + return *(const u16 *)n->primary_key == *(const u16 *)pkey; +} + +static inline bool neigh_key_eq32(const struct neighbour *n, const void *pkey) +{ + return *(const u32 *)n->primary_key == *(const u32 *)pkey; +} + +static inline bool neigh_key_eq128(const struct neighbour *n, const void *pkey) +{ + const u32 *n32 = (const u32 *)n->primary_key; + const u32 *p32 = pkey; + + return ((n32[0] ^ p32[0]) | (n32[1] ^ p32[1]) | + (n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0; +} + +static inline struct neighbour *___neigh_lookup_noref( + struct neigh_table *tbl, + bool (*key_eq)(const struct neighbour *n, const void *pkey), + __u32 (*hash)(const void *pkey, + const struct net_device *dev, + __u32 *hash_rnd), + const void *pkey, + struct net_device *dev) +{ + struct neigh_hash_table *nht = rcu_dereference_bh(tbl->nht); + struct neighbour *n; + u32 hash_val; + + hash_val = hash(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)) { + if (n->dev == dev && key_eq(n, pkey)) + return n; + } + + return NULL; +} + +static inline struct neighbour *__neigh_lookup_noref(struct neigh_table *tbl, + const void *pkey, + struct net_device *dev) +{ + return ___neigh_lookup_noref(tbl, tbl->key_eq, tbl->hash, pkey, dev); +} + void neigh_table_init(int index, struct neigh_table *tbl); int neigh_table_clear(int index, struct neigh_table *tbl); struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey, -- cgit v1.2.3