Commit 0e3bcb0f authored by Gilad Naaman's avatar Gilad Naaman Committed by Jakub Kicinski
Browse files

neighbour: Convert iteration to use hlist+macro 



Remove all usage of the bare neighbour::next pointer,
replacing them with neighbour::hash and its for_each macro.

Signed-off-by: default avatarGilad Naaman <gnaaman@drivenets.com>
Reviewed-by: default avatarKuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20241107160444.2913124-5-gnaaman@drivenets.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 00df5e1a

include/net/neighbour.h

+1 −4
Original line number Diff line number Diff line
@@ -311,12 +311,9 @@ static inline struct neighbour *___neigh_lookup_noref( 
	u32 hash_val;



	hash_val = hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);

	for (n = rcu_dereference(nht->hash_buckets[hash_val]);

	     n != NULL;

	     n = rcu_dereference(n->next)) {

	neigh_for_each_in_bucket_rcu(n, &nht->hash_heads[hash_val])

		if (n->dev == dev && key_eq(n, pkey))

			return n;

	}



	return NULL;

}

net/core/neighbour.c

+18 −29
Original line number Diff line number Diff line
@@ -387,11 +387,11 @@ static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev, 
					lockdep_is_held(&tbl->lock));



	for (i = 0; i < (1 << nht->hash_shift); i++) {

		struct neighbour *n;

		struct neighbour __rcu **np = &nht->hash_buckets[i];

		struct hlist_node *tmp;

		struct neighbour *n;



		while ((n = rcu_dereference_protected(*np,

					lockdep_is_held(&tbl->lock))) != NULL) {

		neigh_for_each_in_bucket_safe(n, tmp, &nht->hash_heads[i]) {

			if (dev && n->dev != dev) {

				np = &n->next;

				continue;
@@ -587,18 +587,14 @@ static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl, 
		return old_nht;



	for (i = 0; i < (1 << old_nht->hash_shift); i++) {

		struct neighbour *n, *next;

		struct hlist_node *tmp;

		struct neighbour *n;



		for (n = rcu_dereference_protected(old_nht->hash_buckets[i],

						   lockdep_is_held(&tbl->lock));

		     n != NULL;

		     n = next) {

		neigh_for_each_in_bucket_safe(n, tmp, &old_nht->hash_heads[i]) {

			hash = tbl->hash(n->primary_key, n->dev,

					 new_nht->hash_rnd);



			hash >>= (32 - new_nht->hash_shift);

			next = rcu_dereference_protected(n->next,

						lockdep_is_held(&tbl->lock));



			rcu_assign_pointer(n->next,

					   rcu_dereference_protected(
@@ -693,11 +689,7 @@ ___neigh_create(struct neigh_table *tbl, const void *pkey, 
		goto out_tbl_unlock;

	}



	for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val],

					    lockdep_is_held(&tbl->lock));

	     n1 != NULL;

	     n1 = rcu_dereference_protected(n1->next,

			lockdep_is_held(&tbl->lock))) {

	neigh_for_each_in_bucket(n1, &nht->hash_heads[hash_val]) {

		if (dev == n1->dev && !memcmp(n1->primary_key, n->primary_key, key_len)) {

			if (want_ref)

				neigh_hold(n1);
@@ -949,10 +941,11 @@ static void neigh_connect(struct neighbour *neigh) 
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;

	struct neigh_hash_table *nht;

	struct neighbour __rcu **np;

	struct hlist_node *tmp;

	struct neighbour *n;

	unsigned int i;

	struct neigh_hash_table *nht;



	NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
@@ -979,8 +972,7 @@ static void neigh_periodic_work(struct work_struct *work) 
	for (i = 0 ; i < (1 << nht->hash_shift); i++) {

		np = &nht->hash_buckets[i];



		while ((n = rcu_dereference_protected(*np,

				lockdep_is_held(&tbl->lock))) != NULL) {

		neigh_for_each_in_bucket_safe(n, tmp, &nht->hash_heads[i]) {

			unsigned int state;



			write_lock(&n->lock);
@@ -2730,9 +2722,8 @@ static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb, 
	for (h = s_h; h < (1 << nht->hash_shift); h++) {

		if (h > s_h)

			s_idx = 0;

		for (n = rcu_dereference(nht->hash_buckets[h]), idx = 0;

		     n != NULL;

		     n = rcu_dereference(n->next)) {

		idx = 0;

		neigh_for_each_in_bucket_rcu(n, &nht->hash_heads[h]) {

			if (idx < s_idx || !net_eq(dev_net(n->dev), net))

				goto next;

			if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
@@ -3099,9 +3090,7 @@ void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void 
	for (chain = 0; chain < (1 << nht->hash_shift); chain++) {

		struct neighbour *n;



		for (n = rcu_dereference(nht->hash_buckets[chain]);

		     n != NULL;

		     n = rcu_dereference(n->next))

		neigh_for_each_in_bucket(n, &nht->hash_heads[chain])

			cb(n, cookie);

	}

	read_unlock_bh(&tbl->lock);
@@ -3113,18 +3102,18 @@ EXPORT_SYMBOL(neigh_for_each); 
void __neigh_for_each_release(struct neigh_table *tbl,

			      int (*cb)(struct neighbour *))

{

	int chain;

	struct neigh_hash_table *nht;

	int chain;



	nht = rcu_dereference_protected(tbl->nht,

					lockdep_is_held(&tbl->lock));

	for (chain = 0; chain < (1 << nht->hash_shift); chain++) {

		struct neighbour *n;

		struct neighbour __rcu **np;

		struct hlist_node *tmp;

		struct neighbour *n;



		np = &nht->hash_buckets[chain];

		while ((n = rcu_dereference_protected(*np,

					lockdep_is_held(&tbl->lock))) != NULL) {

		neigh_for_each_in_bucket_safe(n, tmp, &nht->hash_heads[chain]) {

			int release;



			write_lock(&n->lock);