[PATCH net-next 5/7] neighbor: Create a neigh_hash helper

[David Ahern]

From: David Ahern <dsah...@gmail.com>

Consolidate calculations of the neighbor hash into a single helper.

Signed-off-by: David Ahern <dsah...@gmail.com>
---
 include/net/neighbour.h | 10 +++++++++-
 net/core/neighbour.c    | 15 +++++----------
 2 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/include/net/neighbour.h b/include/net/neighbour.h
index aac87bc2d96b..092493a8c91b 100644
--- a/include/net/neighbour.h
+++ b/include/net/neighbour.h
@@ -270,6 +270,14 @@ static inline bool neigh_key_eq128(const struct neighbour 
*n, const void *pkey)
                (n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0;
 }
 
+static inline u32 neigh_hash(struct neigh_table *tbl,
+                            struct neigh_hash_table *nht,
+                            const void *pkey,
+                            struct net_device *dev)
+{
+       return tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
+}
+
 static inline struct neighbour *__neigh_lookup_noref(struct neigh_table *tbl,
                                                     const void *pkey,
                                                     struct net_device *dev)
@@ -278,7 +286,7 @@ static inline struct neighbour *__neigh_lookup_noref(struct 
neigh_table *tbl,
        struct neighbour *n;
        u32 hash_val;
 
-       hash_val = tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - 
nht->hash_shift);
+       hash_val = neigh_hash(tbl, nht, pkey, dev);
        for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
             n != NULL;
             n = rcu_dereference_bh(n->next)) {
diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index 41954e42a2de..53e30c15882d 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -151,9 +151,8 @@ bool neigh_remove_one(struct neighbour *ndel, struct 
neigh_table *tbl)
 
        nht = rcu_dereference_protected(tbl->nht,
                                        lockdep_is_held(&tbl->lock));
-       hash_val = tbl->hash(pkey, ndel->dev, nht->hash_rnd);
-       hash_val = hash_val >> (32 - nht->hash_shift);
 
+       hash_val = neigh_hash(tbl, nht, pkey, ndel->dev);
        np = &nht->hash_buckets[hash_val];
        while ((n = rcu_dereference_protected(*np,
                                              lockdep_is_held(&tbl->lock)))) {
@@ -434,10 +433,7 @@ static struct neigh_hash_table *neigh_hash_grow(struct 
neigh_table *tbl,
                                                   lockdep_is_held(&tbl->lock));
                     n != NULL;
                     n = next) {
-                       hash = tbl->hash(n->primary_key, n->dev,
-                                        new_nht->hash_rnd);
-
-                       hash >>= (32 - new_nht->hash_shift);
+                       hash = neigh_hash(tbl, new_nht, n->primary_key, n->dev);
                        next = rcu_dereference_protected(n->next,
                                                lockdep_is_held(&tbl->lock));
 
@@ -485,9 +481,9 @@ struct neighbour *neigh_lookup_nodev(struct neigh_table 
*tbl, struct net *net,
        NEIGH_CACHE_STAT_INC(tbl, lookups);
 
        rcu_read_lock_bh();
-       nht = rcu_dereference_bh(tbl->nht);
-       hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - 
nht->hash_shift);
 
+       nht = rcu_dereference_bh(tbl->nht);
+       hash_val = neigh_hash(tbl, nht, pkey, NULL);
        for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
             n != NULL;
             n = rcu_dereference_bh(n->next)) {
@@ -553,13 +549,12 @@ struct neighbour *__neigh_create(struct neigh_table *tbl, 
const void *pkey,
        if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
                nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
 
-       hash_val = tbl->hash(n->primary_key, dev, nht->hash_rnd) >> (32 - 
nht->hash_shift);
-
        if (n->parms->dead) {
                rc = ERR_PTR(-EINVAL);
                goto out_tbl_unlock;
        }
 
+       hash_val = neigh_hash(tbl, nht, n->primary_key, dev);
        for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val],
                                            lockdep_is_held(&tbl->lock));
             n1 != NULL;
-- 
2.11.0