net neigh: RCU conversion of neigh hash table

David

This is the first step for RCU conversion of neigh code.

Next patches will convert hash_buckets[] and "struct neighbour" to RCU
protected objects.

Thanks

[PATCH net-next] net neigh: RCU conversion of neigh hash table

Instead of storing hash_buckets, hash_mask and hash_rnd in "struct
neigh_table", a new structure is defined :

struct neigh_hash_table {
       struct neighbour        **hash_buckets;
       unsigned int            hash_mask;
       __u32                   hash_rnd;
       struct rcu_head         rcu;
};

And "struct neigh_table" has an RCU protected pointer to such a
neigh_hash_table.

This means the signature of (*hash)() function changed: We need to add a
third parameter with the actual hash_rnd value, since this is not
anymore a neigh_table field.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/neighbour.h b/include/net/neighbour.h
index 7d08fd1062f092634daa1dc1d659ac9d34a8c4e8..37845dae6488b6df58e2e200ac0d7a7732098323 100644 (file)
--- a/include/net/neighbour.h
+++ b/include/net/neighbour.h
@@ -138,13 +138,22 @@ struct pneigh_entry {
  *     neighbour table manipulation
  */
 
+struct neigh_hash_table {
+       struct neighbour        **hash_buckets;
+       unsigned int            hash_mask;
+       __u32                   hash_rnd;
+       struct rcu_head         rcu;
+};
+
 
 struct neigh_table {
        struct neigh_table      *next;
        int                     family;
        int                     entry_size;
        int                     key_len;
-       __u32                   (*hash)(const void *pkey, const struct net_device *);
+       __u32                   (*hash)(const void *pkey,
+                                       const struct net_device *dev,
+                                       __u32 hash_rnd);
        int                     (*constructor)(struct neighbour *);
        int                     (*pconstructor)(struct pneigh_entry *);
        void                    (*pdestructor)(struct pneigh_entry *);
@@ -165,9 +174,7 @@ struct neigh_table {
        unsigned long           last_rand;
        struct kmem_cache       *kmem_cachep;
        struct neigh_statistics __percpu *stats;
-       struct neighbour        **hash_buckets;
-       unsigned int            hash_mask;
-       __u32                   hash_rnd;
+       struct neigh_hash_table __rcu *nht;
        struct pneigh_entry     **phash_buckets;
 };
 
@@ -237,6 +244,7 @@ extern void pneigh_for_each(struct neigh_table *tbl, void (*cb)(struct pneigh_en
 struct neigh_seq_state {
        struct seq_net_private p;
        struct neigh_table *tbl;
+       struct neigh_hash_table *nht;
        void *(*neigh_sub_iter)(struct neigh_seq_state *state,
                                struct neighbour *n, loff_t *pos);
        unsigned int bucket;

diff --git a/net/atm/clip.c b/net/atm/clip.c
index 95fdd1185067a859d49d0f5f5ea246e4fcad0893..ff956d1115bcee4636a68011a38457d87bea3cdd 100644 (file)
--- a/net/atm/clip.c
+++ b/net/atm/clip.c
@@ -310,9 +310,9 @@ static int clip_constructor(struct neighbour *neigh)
        return 0;
 }
 
-static u32 clip_hash(const void *pkey, const struct net_device *dev)
+static u32 clip_hash(const void *pkey, const struct net_device *dev, __u32 rnd)
 {
-       return jhash_2words(*(u32 *) pkey, dev->ifindex, clip_tbl.hash_rnd);
+       return jhash_2words(*(u32 *) pkey, dev->ifindex, rnd);
 }
 
 static struct neigh_table clip_tbl = {

diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index d6996e072a41bcc67870b281b0723dd3f02dbfa8..dd8920e4f508fe5b55a1b53c805c9316df2d2c2d 100644 (file)
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -131,14 +131,17 @@ static int neigh_forced_gc(struct neigh_table *tbl)
 {
        int shrunk = 0;
        int i;
+       struct neigh_hash_table *nht;
 
        NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
 
        write_lock_bh(&tbl->lock);
-       for (i = 0; i <= tbl->hash_mask; i++) {
+       nht = rcu_dereference_protected(tbl->nht,
+                                       lockdep_is_held(&tbl->lock));
+       for (i = 0; i <= nht->hash_mask; i++) {
                struct neighbour *n, **np;
 
-               np = &tbl->hash_buckets[i];
+               np = &nht->hash_buckets[i];
                while ((n = *np) != NULL) {
                        /* Neighbour record may be discarded if:
                         * - nobody refers to it.
@@ -199,9 +202,13 @@ static void pneigh_queue_purge(struct sk_buff_head *list)
 static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev)
 {
        int i;
+       struct neigh_hash_table *nht;
 
-       for (i = 0; i <= tbl->hash_mask; i++) {
-               struct neighbour *n, **np = &tbl->hash_buckets[i];
+       nht = rcu_dereference_protected(tbl->nht,
+                                       lockdep_is_held(&tbl->lock));
+
+       for (i = 0; i <= nht->hash_mask; i++) {
+               struct neighbour *n, **np = &nht->hash_buckets[i];
 
                while ((n = *np) != NULL) {
                        if (dev && n->dev != dev) {
@@ -297,64 +304,81 @@ out_entries:
        goto out;
 }
 
-static struct neighbour **neigh_hash_alloc(unsigned int entries)
+static struct neigh_hash_table *neigh_hash_alloc(unsigned int entries)
 {
-       unsigned long size = entries * sizeof(struct neighbour *);
-       struct neighbour **ret;
+       size_t size = entries * sizeof(struct neighbour *);
+       struct neigh_hash_table *ret;
+       struct neighbour **buckets;
 
-       if (size <= PAGE_SIZE) {
-               ret = kzalloc(size, GFP_ATOMIC);
-       } else {
-               ret = (struct neighbour **)
-                     __get_free_pages(GFP_ATOMIC|__GFP_ZERO, get_order(size));
+       ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
+       if (!ret)
+               return NULL;
+       if (size <= PAGE_SIZE)
+               buckets = kzalloc(size, GFP_ATOMIC);
+       else
+               buckets = (struct neighbour **)
+                         __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
+                                          get_order(size));
+       if (!buckets) {
+               kfree(ret);
+               return NULL;
        }
+       ret->hash_buckets = buckets;
+       ret->hash_mask = entries - 1;
+       get_random_bytes(&ret->hash_rnd, sizeof(ret->hash_rnd));
        return ret;
 }
 
-static void neigh_hash_free(struct neighbour **hash, unsigned int entries)
+static void neigh_hash_free_rcu(struct rcu_head *head)
 {
-       unsigned long size = entries * sizeof(struct neighbour *);
+       struct neigh_hash_table *nht = container_of(head,
+                                                   struct neigh_hash_table,
+                                                   rcu);
+       size_t size = (nht->hash_mask + 1) * sizeof(struct neighbour *);
+       struct neighbour **buckets = nht->hash_buckets;
 
        if (size <= PAGE_SIZE)
-               kfree(hash);
+               kfree(buckets);
        else
-               free_pages((unsigned long)hash, get_order(size));
+               free_pages((unsigned long)buckets, get_order(size));
+       kfree(nht);
 }
 
-static void neigh_hash_grow(struct neigh_table *tbl, unsigned long new_entries)
+static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
+                                               unsigned long new_entries)
 {
-       struct neighbour **new_hash, **old_hash;
-       unsigned int i, new_hash_mask, old_entries;
+       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));
-       new_hash = neigh_hash_alloc(new_entries);
-       if (!new_hash)
-               return;
+       old_nht = rcu_dereference_protected(tbl->nht,
+                                           lockdep_is_held(&tbl->lock));
+       new_nht = neigh_hash_alloc(new_entries);
+       if (!new_nht)
+               return old_nht;
 
-       old_entries = tbl->hash_mask + 1;
-       new_hash_mask = new_entries - 1;
-       old_hash = tbl->hash_buckets;
-
-       get_random_bytes(&tbl->hash_rnd, sizeof(tbl->hash_rnd));
-       for (i = 0; i < old_entries; i++) {
+       for (i = 0; i <= old_nht->hash_mask; i++) {
                struct neighbour *n, *next;
 
-               for (n = old_hash[i]; n; n = next) {
-                       unsigned int hash_val = tbl->hash(n->primary_key, n->dev);
+               for (n = old_nht->hash_buckets[i];
+                    n != NULL;
+                    n = next) {
+                       hash = tbl->hash(n->primary_key, n->dev,
+                                        new_nht->hash_rnd);
 
-                       hash_val &= new_hash_mask;
+                       hash &= new_nht->hash_mask;
                        next = n->next;
 
-                       n->next = new_hash[hash_val];
-                       new_hash[hash_val] = n;
+                       n->next = new_nht->hash_buckets[hash];
+                       new_nht->hash_buckets[hash] = n;
                }
        }
-       tbl->hash_buckets = new_hash;
-       tbl->hash_mask = new_hash_mask;
 
-       neigh_hash_free(old_hash, old_entries);
+       rcu_assign_pointer(tbl->nht, new_nht);
+       call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
+       return new_nht;
 }
 
 struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
@@ -363,19 +387,23 @@ struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
        struct neighbour *n;
        int key_len = tbl->key_len;
        u32 hash_val;
+       struct neigh_hash_table *nht;
 
        NEIGH_CACHE_STAT_INC(tbl, lookups);
 
-       read_lock_bh(&tbl->lock);
-       hash_val = tbl->hash(pkey, dev);
-       for (n = tbl->hash_buckets[hash_val & tbl->hash_mask]; n; n = n->next) {
+       rcu_read_lock_bh();
+       nht = rcu_dereference_bh(tbl->nht);
+       hash_val = tbl->hash(pkey, dev, nht->hash_rnd) & nht->hash_mask;
+       read_lock(&tbl->lock);
+       for (n = nht->hash_buckets[hash_val]; n; n = n->next) {
                if (dev == n->dev && !memcmp(n->primary_key, pkey, key_len)) {
                        neigh_hold(n);
                        NEIGH_CACHE_STAT_INC(tbl, hits);
                        break;
                }
        }
-       read_unlock_bh(&tbl->lock);
+       read_unlock(&tbl->lock);
+       rcu_read_unlock_bh();
        return n;
 }
 EXPORT_SYMBOL(neigh_lookup);
@@ -386,12 +414,15 @@ struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
        struct neighbour *n;
        int key_len = tbl->key_len;
        u32 hash_val;
+       struct neigh_hash_table *nht;
 
        NEIGH_CACHE_STAT_INC(tbl, lookups);
 
-       read_lock_bh(&tbl->lock);
-       hash_val = tbl->hash(pkey, NULL);
-       for (n = tbl->hash_buckets[hash_val & tbl->hash_mask]; n; n = n->next) {
+       rcu_read_lock_bh();
+       nht = rcu_dereference_bh(tbl->nht);
+       hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) & nht->hash_mask;
+       read_lock(&tbl->lock);
+       for (n = nht->hash_buckets[hash_val]; n; n = n->next) {
                if (!memcmp(n->primary_key, pkey, key_len) &&
                    net_eq(dev_net(n->dev), net)) {
                        neigh_hold(n);
@@ -399,7 +430,8 @@ struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
                        break;
                }
        }
-       read_unlock_bh(&tbl->lock);
+       read_unlock(&tbl->lock);
+       rcu_read_unlock_bh();
        return n;
 }
 EXPORT_SYMBOL(neigh_lookup_nodev);
@@ -411,6 +443,7 @@ struct neighbour *neigh_create(struct neigh_table *tbl, const void *pkey,
        int key_len = tbl->key_len;
        int error;
        struct neighbour *n1, *rc, *n = neigh_alloc(tbl);
+       struct neigh_hash_table *nht;
 
        if (!n) {
                rc = ERR_PTR(-ENOBUFS);
@@ -437,18 +470,20 @@ struct neighbour *neigh_create(struct neigh_table *tbl, const void *pkey,
        n->confirmed = jiffies - (n->parms->base_reachable_time << 1);
 
        write_lock_bh(&tbl->lock);
+       nht = rcu_dereference_protected(tbl->nht,
+                                       lockdep_is_held(&tbl->lock));
 
-       if (atomic_read(&tbl->entries) > (tbl->hash_mask + 1))
-               neigh_hash_grow(tbl, (tbl->hash_mask + 1) << 1);
+       if (atomic_read(&tbl->entries) > (nht->hash_mask + 1))
+               nht = neigh_hash_grow(tbl, (nht->hash_mask + 1) << 1);
 
-       hash_val = tbl->hash(pkey, dev) & tbl->hash_mask;
+       hash_val = tbl->hash(pkey, dev, nht->hash_rnd) & nht->hash_mask;
 
        if (n->parms->dead) {
                rc = ERR_PTR(-EINVAL);
                goto out_tbl_unlock;
        }
 
-       for (n1 = tbl->hash_buckets[hash_val]; n1; n1 = n1->next) {
+       for (n1 = nht->hash_buckets[hash_val]; n1; n1 = n1->next) {
                if (dev == n1->dev && !memcmp(n1->primary_key, pkey, key_len)) {
                        neigh_hold(n1);
                        rc = n1;
@@ -456,8 +491,8 @@ struct neighbour *neigh_create(struct neigh_table *tbl, const void *pkey,
                }
        }
 
-       n->next = tbl->hash_buckets[hash_val];
-       tbl->hash_buckets[hash_val] = n;
+       n->next = nht->hash_buckets[hash_val];
+       nht->hash_buckets[hash_val] = n;
        n->dead = 0;
        neigh_hold(n);
        write_unlock_bh(&tbl->lock);
@@ -698,10 +733,13 @@ static void neigh_periodic_work(struct work_struct *work)
        struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
        struct neighbour *n, **np;
        unsigned int i;
+       struct neigh_hash_table *nht;
 
        NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
 
        write_lock_bh(&tbl->lock);
+       nht = rcu_dereference_protected(tbl->nht,
+                                       lockdep_is_held(&tbl->lock));
 
        /*
         *      periodically recompute ReachableTime from random function
@@ -715,8 +753,8 @@ static void neigh_periodic_work(struct work_struct *work)
                                neigh_rand_reach_time(p->base_reachable_time);
        }
 
-       for (i = 0 ; i <= tbl->hash_mask; i++) {
-               np = &tbl->hash_buckets[i];
+       for (i = 0 ; i <= nht->hash_mask; i++) {
+               np = &nht->hash_buckets[i];
 
                while ((n = *np) != NULL) {
                        unsigned int state;
@@ -1438,17 +1476,14 @@ void neigh_table_init_no_netlink(struct neigh_table *tbl)
                panic("cannot create neighbour proc dir entry");
 #endif
 
-       tbl->hash_mask = 1;
-       tbl->hash_buckets = neigh_hash_alloc(tbl->hash_mask + 1);
+       tbl->nht = neigh_hash_alloc(8);
 
        phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
        tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
 
-       if (!tbl->hash_buckets || !tbl->phash_buckets)
+       if (!tbl->nht || !tbl->phash_buckets)
                panic("cannot allocate neighbour cache hashes");
 
-       get_random_bytes(&tbl->hash_rnd, sizeof(tbl->hash_rnd));
-
        rwlock_init(&tbl->lock);
        INIT_DELAYED_WORK_DEFERRABLE(&tbl->gc_work, neigh_periodic_work);
        schedule_delayed_work(&tbl->gc_work, tbl->parms.reachable_time);
@@ -1504,8 +1539,8 @@ int neigh_table_clear(struct neigh_table *tbl)
        }
        write_unlock(&neigh_tbl_lock);
 
-       neigh_hash_free(tbl->hash_buckets, tbl->hash_mask + 1);
-       tbl->hash_buckets = NULL;
+       call_rcu(&tbl->nht->rcu, neigh_hash_free_rcu);
+       tbl->nht = NULL;
 
        kfree(tbl->phash_buckets);
        tbl->phash_buckets = NULL;
@@ -1745,18 +1780,22 @@ static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
                unsigned long now = jiffies;
                unsigned int flush_delta = now - tbl->last_flush;
                unsigned int rand_delta = now - tbl->last_rand;
-
+               struct neigh_hash_table *nht;
                struct ndt_config ndc = {
                        .ndtc_key_len           = tbl->key_len,
                        .ndtc_entry_size        = tbl->entry_size,
                        .ndtc_entries           = atomic_read(&tbl->entries),
                        .ndtc_last_flush        = jiffies_to_msecs(flush_delta),
                        .ndtc_last_rand         = jiffies_to_msecs(rand_delta),
-                       .ndtc_hash_rnd          = tbl->hash_rnd,
-                       .ndtc_hash_mask         = tbl->hash_mask,
                        .ndtc_proxy_qlen        = tbl->proxy_queue.qlen,
                };
 
+               rcu_read_lock_bh();
+               nht = rcu_dereference_bh(tbl->nht);
+               ndc.ndtc_hash_rnd = nht->hash_rnd;
+               ndc.ndtc_hash_mask = nht->hash_mask;
+               rcu_read_unlock_bh();
+
                NLA_PUT(skb, NDTA_CONFIG, sizeof(ndc), &ndc);
        }
 
@@ -2088,14 +2127,18 @@ static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
        struct neighbour *n;
        int rc, h, s_h = cb->args[1];
        int idx, s_idx = idx = cb->args[2];
+       struct neigh_hash_table *nht;
 
-       read_lock_bh(&tbl->lock);
-       for (h = 0; h <= tbl->hash_mask; h++) {
+       rcu_read_lock_bh();
+       nht = rcu_dereference_bh(tbl->nht);
+
+       read_lock(&tbl->lock);
+       for (h = 0; h <= nht->hash_mask; h++) {
                if (h < s_h)
                        continue;
                if (h > s_h)
                        s_idx = 0;
-               for (n = tbl->hash_buckets[h], idx = 0; n; n = n->next) {
+               for (n = nht->hash_buckets[h], idx = 0; n; n = n->next) {
                        if (!net_eq(dev_net(n->dev), net))
                                continue;
                        if (idx < s_idx)
@@ -2104,7 +2147,6 @@ static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
                                            cb->nlh->nlmsg_seq,
                                            RTM_NEWNEIGH,
                                            NLM_F_MULTI) <= 0) {
-                               read_unlock_bh(&tbl->lock);
                                rc = -1;
                                goto out;
                        }
@@ -2112,9 +2154,10 @@ static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
                        idx++;
                }
        }
-       read_unlock_bh(&tbl->lock);
        rc = skb->len;
 out:
+       read_unlock(&tbl->lock);
+       rcu_read_unlock_bh();
        cb->args[1] = h;
        cb->args[2] = idx;
        return rc;
@@ -2147,15 +2190,20 @@ static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
 void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
 {
        int chain;
+       struct neigh_hash_table *nht;
 
-       read_lock_bh(&tbl->lock);
-       for (chain = 0; chain <= tbl->hash_mask; chain++) {
+       rcu_read_lock_bh();
+       nht = rcu_dereference_bh(tbl->nht);
+
+       read_lock(&tbl->lock);
+       for (chain = 0; chain <= nht->hash_mask; chain++) {
                struct neighbour *n;
 
-               for (n = tbl->hash_buckets[chain]; n; n = n->next)
+               for (n = nht->hash_buckets[chain]; n; n = n->next)
                        cb(n, cookie);
        }
-       read_unlock_bh(&tbl->lock);
+       read_unlock(&tbl->lock);
+       rcu_read_unlock_bh();
 }
 EXPORT_SYMBOL(neigh_for_each);
 
@@ -2164,11 +2212,14 @@ void __neigh_for_each_release(struct neigh_table *tbl,
                              int (*cb)(struct neighbour *))
 {
        int chain;
+       struct neigh_hash_table *nht;
 
-       for (chain = 0; chain <= tbl->hash_mask; chain++) {
+       nht = rcu_dereference_protected(tbl->nht,
+                                       lockdep_is_held(&tbl->lock));
+       for (chain = 0; chain <= nht->hash_mask; chain++) {
                struct neighbour *n, **np;
 
-               np = &tbl->hash_buckets[chain];
+               np = &nht->hash_buckets[chain];
                while ((n = *np) != NULL) {
                        int release;
 
@@ -2193,13 +2244,13 @@ static struct neighbour *neigh_get_first(struct seq_file *seq)
 {
        struct neigh_seq_state *state = seq->private;
        struct net *net = seq_file_net(seq);
-       struct neigh_table *tbl = state->tbl;
+       struct neigh_hash_table *nht = state->nht;
        struct neighbour *n = NULL;
        int bucket = state->bucket;
 
        state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
-       for (bucket = 0; bucket <= tbl->hash_mask; bucket++) {
-               n = tbl->hash_buckets[bucket];
+       for (bucket = 0; bucket <= nht->hash_mask; bucket++) {
+               n = nht->hash_buckets[bucket];
 
                while (n) {
                        if (!net_eq(dev_net(n->dev), net))
@@ -2234,7 +2285,7 @@ static struct neighbour *neigh_get_next(struct seq_file *seq,
 {
        struct neigh_seq_state *state = seq->private;
        struct net *net = seq_file_net(seq);
-       struct neigh_table *tbl = state->tbl;
+       struct neigh_hash_table *nht = state->nht;
 
        if (state->neigh_sub_iter) {
                void *v = state->neigh_sub_iter(state, n, pos);
@@ -2265,10 +2316,10 @@ static struct neighbour *neigh_get_next(struct seq_file *seq,
                if (n)
                        break;
 
-               if (++state->bucket > tbl->hash_mask)
+               if (++state->bucket > nht->hash_mask)
                        break;
 
-               n = tbl->hash_buckets[state->bucket];
+               n = nht->hash_buckets[state->bucket];
        }
 
        if (n && pos)
@@ -2367,6 +2418,7 @@ static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
 
 void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
        __acquires(tbl->lock)
+       __acquires(rcu_bh)
 {
        struct neigh_seq_state *state = seq->private;
 
@@ -2374,8 +2426,9 @@ void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl
        state->bucket = 0;
        state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
 
-       read_lock_bh(&tbl->lock);
-
+       rcu_read_lock_bh();
+       state->nht = rcu_dereference_bh(tbl->nht);
+       read_lock(&tbl->lock);
        return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
 }
 EXPORT_SYMBOL(neigh_seq_start);
@@ -2409,11 +2462,13 @@ EXPORT_SYMBOL(neigh_seq_next);
 
 void neigh_seq_stop(struct seq_file *seq, void *v)
        __releases(tbl->lock)
+       __releases(rcu_bh)
 {
        struct neigh_seq_state *state = seq->private;
        struct neigh_table *tbl = state->tbl;
 
-       read_unlock_bh(&tbl->lock);
+       read_unlock(&tbl->lock);
+       rcu_read_unlock_bh();
 }
 EXPORT_SYMBOL(neigh_seq_stop);
 

diff --git a/net/decnet/dn_neigh.c b/net/decnet/dn_neigh.c
index 0363bb95cc7db606d45dd08bac34340ba48a3a84..a085dbcf5c7fa4fde69419dd135c8c8570bb4fb2 100644 (file)
--- a/net/decnet/dn_neigh.c
+++ b/net/decnet/dn_neigh.c
@@ -48,7 +48,6 @@
 #include <net/dn_neigh.h>
 #include <net/dn_route.h>
 
-static u32 dn_neigh_hash(const void *pkey, const struct net_device *dev);
 static int dn_neigh_construct(struct neighbour *);
 static void dn_long_error_report(struct neighbour *, struct sk_buff *);
 static void dn_short_error_report(struct neighbour *, struct sk_buff *);
@@ -93,6 +92,13 @@ static const struct neigh_ops dn_phase3_ops = {
        .queue_xmit =           dev_queue_xmit
 };
 
+static u32 dn_neigh_hash(const void *pkey,
+                        const struct net_device *dev,
+                        __u32 hash_rnd)
+{
+       return jhash_2words(*(__u16 *)pkey, 0, hash_rnd);
+}
+
 struct neigh_table dn_neigh_table = {
        .family =                       PF_DECnet,
        .entry_size =                   sizeof(struct dn_neigh),
@@ -122,11 +128,6 @@ struct neigh_table dn_neigh_table = {
        .gc_thresh3 =                   1024,
 };
 
-static u32 dn_neigh_hash(const void *pkey, const struct net_device *dev)
-{
-       return jhash_2words(*(__u16 *)pkey, 0, dn_neigh_table.hash_rnd);
-}
-
 static int dn_neigh_construct(struct neighbour *neigh)
 {
        struct net_device *dev = neigh->dev;

diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c
index d9031ad67826f99b71f50acd90c91de61ba6d7be..f35309578170960bd8f0f73cac1eeebd8bb4c78d 100644 (file)
--- a/net/ipv4/arp.c
+++ b/net/ipv4/arp.c
@@ -127,7 +127,7 @@ EXPORT_SYMBOL(clip_tbl_hook);
 /*
  *     Interface to generic neighbour cache.
  */
-static u32 arp_hash(const void *pkey, const struct net_device *dev);
+static u32 arp_hash(const void *pkey, const struct net_device *dev, __u32 rnd);
 static int arp_constructor(struct neighbour *neigh);
 static void arp_solicit(struct neighbour *neigh, struct sk_buff *skb);
 static void arp_error_report(struct neighbour *neigh, struct sk_buff *skb);
@@ -225,9 +225,11 @@ int arp_mc_map(__be32 addr, u8 *haddr, struct net_device *dev, int dir)
 }
 
 
-static u32 arp_hash(const void *pkey, const struct net_device *dev)
+static u32 arp_hash(const void *pkey,
+                   const struct net_device *dev,
+                   __u32 hash_rnd)
 {
-       return jhash_2words(*(u32 *)pkey, dev->ifindex, arp_tbl.hash_rnd);
+       return jhash_2words(*(u32 *)pkey, dev->ifindex, hash_rnd);
 }
 
 static int arp_constructor(struct neighbour *neigh)

diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index b3dd844cd34fea9d53f917006b395c2e9f30e46a..998d6d27e7cf293383b7c4e944899790170ba690 100644 (file)
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -91,7 +91,9 @@
 #include <linux/netfilter.h>
 #include <linux/netfilter_ipv6.h>
 
-static u32 ndisc_hash(const void *pkey, const struct net_device *dev);
+static u32 ndisc_hash(const void *pkey,
+                     const struct net_device *dev,
+                     __u32 rnd);
 static int ndisc_constructor(struct neighbour *neigh);
 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb);
 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb);
@@ -350,7 +352,9 @@ int ndisc_mc_map(struct in6_addr *addr, char *buf, struct net_device *dev, int d
 
 EXPORT_SYMBOL(ndisc_mc_map);
 
-static u32 ndisc_hash(const void *pkey, const struct net_device *dev)
+static u32 ndisc_hash(const void *pkey,
+                     const struct net_device *dev,
+                     __u32 hash_rnd)
 {
        const u32 *p32 = pkey;
        u32 addr_hash, i;
@@ -359,7 +363,7 @@ static u32 ndisc_hash(const void *pkey, const struct net_device *dev)
        for (i = 0; i < (sizeof(struct in6_addr) / sizeof(u32)); i++)
                addr_hash ^= *p32++;
 
-       return jhash_2words(addr_hash, dev->ifindex, nd_tbl.hash_rnd);
+       return jhash_2words(addr_hash, dev->ifindex, hash_rnd);
 }
 
 static int ndisc_constructor(struct neighbour *neigh)