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-rw-r--r--include/net/arp.h7
-rw-r--r--include/net/neighbour.h2
-rw-r--r--net/core/neighbour.c48
-rw-r--r--net/ipv4/arp.c3
4 files changed, 33 insertions, 27 deletions
diff --git a/include/net/arp.h b/include/net/arp.h
index 91f0568a04ef..723bde501c64 100644
--- a/include/net/arp.h
+++ b/include/net/arp.h
@@ -8,6 +8,13 @@
extern struct neigh_table arp_tbl;
+static inline u32 arp_hashfn(u32 key, const struct net_device *dev, u32 hash_rnd)
+{
+ u32 val = key ^ dev->ifindex;
+
+ return val * hash_rnd;
+}
+
extern void arp_init(void);
extern int arp_find(unsigned char *haddr, struct sk_buff *skb);
extern int arp_ioctl(struct net *net, unsigned int cmd, void __user *arg);
diff --git a/include/net/neighbour.h b/include/net/neighbour.h
index 4014b623880c..6fe8c2cd5acb 100644
--- a/include/net/neighbour.h
+++ b/include/net/neighbour.h
@@ -142,7 +142,7 @@ struct pneigh_entry {
struct neigh_hash_table {
struct neighbour __rcu **hash_buckets;
- unsigned int hash_mask;
+ unsigned int hash_shift;
__u32 hash_rnd;
struct rcu_head rcu;
};
diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index ceb505b1507c..50bd960983e0 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -137,7 +137,7 @@ static int neigh_forced_gc(struct neigh_table *tbl)
write_lock_bh(&tbl->lock);
nht = rcu_dereference_protected(tbl->nht,
lockdep_is_held(&tbl->lock));
- for (i = 0; i <= nht->hash_mask; i++) {
+ for (i = 0; i < (1 << nht->hash_shift); i++) {
struct neighbour *n;
struct neighbour __rcu **np;
@@ -210,7 +210,7 @@ static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev)
nht = rcu_dereference_protected(tbl->nht,
lockdep_is_held(&tbl->lock));
- for (i = 0; i <= nht->hash_mask; i++) {
+ for (i = 0; i < (1 << nht->hash_shift); i++) {
struct neighbour *n;
struct neighbour __rcu **np = &nht->hash_buckets[i];
@@ -312,9 +312,9 @@ out_entries:
goto out;
}
-static struct neigh_hash_table *neigh_hash_alloc(unsigned int entries)
+static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
{
- size_t size = entries * sizeof(struct neighbour *);
+ size_t size = (1 << shift) * sizeof(struct neighbour *);
struct neigh_hash_table *ret;
struct neighbour __rcu **buckets;
@@ -332,8 +332,9 @@ static struct neigh_hash_table *neigh_hash_alloc(unsigned int entries)
return NULL;
}
ret->hash_buckets = buckets;
- ret->hash_mask = entries - 1;
+ ret->hash_shift = shift;
get_random_bytes(&ret->hash_rnd, sizeof(ret->hash_rnd));
+ ret->hash_rnd |= 1;
return ret;
}
@@ -342,7 +343,7 @@ static void neigh_hash_free_rcu(struct rcu_head *head)
struct neigh_hash_table *nht = container_of(head,
struct neigh_hash_table,
rcu);
- size_t size = (nht->hash_mask + 1) * sizeof(struct neighbour *);
+ size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
struct neighbour __rcu **buckets = nht->hash_buckets;
if (size <= PAGE_SIZE)
@@ -353,21 +354,20 @@ static void neigh_hash_free_rcu(struct rcu_head *head)
}
static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
- unsigned long new_entries)
+ unsigned long new_shift)
{
unsigned int i, hash;
struct neigh_hash_table *new_nht, *old_nht;
NEIGH_CACHE_STAT_INC(tbl, hash_grows);
- BUG_ON(!is_power_of_2(new_entries));
old_nht = rcu_dereference_protected(tbl->nht,
lockdep_is_held(&tbl->lock));
- new_nht = neigh_hash_alloc(new_entries);
+ new_nht = neigh_hash_alloc(new_shift);
if (!new_nht)
return old_nht;
- for (i = 0; i <= old_nht->hash_mask; i++) {
+ for (i = 0; i < (1 << old_nht->hash_shift); i++) {
struct neighbour *n, *next;
for (n = rcu_dereference_protected(old_nht->hash_buckets[i],
@@ -377,7 +377,7 @@ static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
hash = tbl->hash(n->primary_key, n->dev,
new_nht->hash_rnd);
- hash &= new_nht->hash_mask;
+ hash >>= (32 - new_nht->hash_shift);
next = rcu_dereference_protected(n->next,
lockdep_is_held(&tbl->lock));
@@ -406,7 +406,7 @@ struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
rcu_read_lock_bh();
nht = rcu_dereference_bh(tbl->nht);
- hash_val = tbl->hash(pkey, dev, nht->hash_rnd) & nht->hash_mask;
+ hash_val = tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
n != NULL;
@@ -436,7 +436,7 @@ struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
rcu_read_lock_bh();
nht = rcu_dereference_bh(tbl->nht);
- hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) & nht->hash_mask;
+ hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - nht->hash_shift);
for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
n != NULL;
@@ -492,10 +492,10 @@ struct neighbour *neigh_create(struct neigh_table *tbl, const void *pkey,
nht = rcu_dereference_protected(tbl->nht,
lockdep_is_held(&tbl->lock));
- if (atomic_read(&tbl->entries) > (nht->hash_mask + 1))
- nht = neigh_hash_grow(tbl, (nht->hash_mask + 1) << 1);
+ if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
+ nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
- hash_val = tbl->hash(pkey, dev, nht->hash_rnd) & nht->hash_mask;
+ hash_val = tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
if (n->parms->dead) {
rc = ERR_PTR(-EINVAL);
@@ -784,7 +784,7 @@ static void neigh_periodic_work(struct work_struct *work)
neigh_rand_reach_time(p->base_reachable_time);
}
- for (i = 0 ; i <= nht->hash_mask; i++) {
+ for (i = 0 ; i < (1 << nht->hash_shift); i++) {
np = &nht->hash_buckets[i];
while ((n = rcu_dereference_protected(*np,
@@ -1540,7 +1540,7 @@ void neigh_table_init_no_netlink(struct neigh_table *tbl)
panic("cannot create neighbour proc dir entry");
#endif
- RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(8));
+ RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
@@ -1857,7 +1857,7 @@ static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
rcu_read_lock_bh();
nht = rcu_dereference_bh(tbl->nht);
ndc.ndtc_hash_rnd = nht->hash_rnd;
- ndc.ndtc_hash_mask = nht->hash_mask;
+ ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
rcu_read_unlock_bh();
NLA_PUT(skb, NDTA_CONFIG, sizeof(ndc), &ndc);
@@ -2200,7 +2200,7 @@ static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
rcu_read_lock_bh();
nht = rcu_dereference_bh(tbl->nht);
- for (h = 0; h <= nht->hash_mask; h++) {
+ for (h = 0; h < (1 << nht->hash_shift); h++) {
if (h < s_h)
continue;
if (h > s_h)
@@ -2264,7 +2264,7 @@ void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void
nht = rcu_dereference_bh(tbl->nht);
read_lock(&tbl->lock); /* avoid resizes */
- for (chain = 0; chain <= nht->hash_mask; chain++) {
+ for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
struct neighbour *n;
for (n = rcu_dereference_bh(nht->hash_buckets[chain]);
@@ -2286,7 +2286,7 @@ void __neigh_for_each_release(struct neigh_table *tbl,
nht = rcu_dereference_protected(tbl->nht,
lockdep_is_held(&tbl->lock));
- for (chain = 0; chain <= nht->hash_mask; chain++) {
+ for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
struct neighbour *n;
struct neighbour __rcu **np;
@@ -2323,7 +2323,7 @@ static struct neighbour *neigh_get_first(struct seq_file *seq)
int bucket = state->bucket;
state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
- for (bucket = 0; bucket <= nht->hash_mask; bucket++) {
+ for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
n = rcu_dereference_bh(nht->hash_buckets[bucket]);
while (n) {
@@ -2390,7 +2390,7 @@ next:
if (n)
break;
- if (++state->bucket > nht->hash_mask)
+ if (++state->bucket >= (1 << nht->hash_shift))
break;
n = rcu_dereference_bh(nht->hash_buckets[state->bucket]);
diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c
index 1b74d3b64371..4412b57f6ff6 100644
--- a/net/ipv4/arp.c
+++ b/net/ipv4/arp.c
@@ -97,7 +97,6 @@
#include <linux/init.h>
#include <linux/net.h>
#include <linux/rcupdate.h>
-#include <linux/jhash.h>
#include <linux/slab.h>
#ifdef CONFIG_SYSCTL
#include <linux/sysctl.h>
@@ -232,7 +231,7 @@ static u32 arp_hash(const void *pkey,
const struct net_device *dev,
__u32 hash_rnd)
{
- return jhash_2words(*(u32 *)pkey, dev->ifindex, hash_rnd);
+ return arp_hashfn(*(u32 *)pkey, dev, hash_rnd);
}
static int arp_constructor(struct neighbour *neigh)