neighbour: switch to standard rcu, instead of rcu_bh

rcu_bh is no longer a win, especially for objects freed
with standard call_rcu().

Switch neighbour code to no longer disable BH when not necessary.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 32 insertions, 32 deletions

diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index 90d399b3f980..ddd0f32de20e 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -614,7 +614,7 @@ struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
 
 	NEIGH_CACHE_STAT_INC(tbl, lookups);
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	n = __neigh_lookup_noref(tbl, pkey, dev);
 	if (n) {
 		if (!refcount_inc_not_zero(&n->refcnt))
@@ -622,7 +622,7 @@ struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
 		NEIGH_CACHE_STAT_INC(tbl, hits);
 	}
 
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 	return n;
 }
 EXPORT_SYMBOL(neigh_lookup);
@@ -2184,11 +2184,11 @@ static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
 			.ndtc_proxy_qlen	= tbl->proxy_queue.qlen,
 		};
 
-		rcu_read_lock_bh();
-		nht = rcu_dereference_bh(tbl->nht);
+		rcu_read_lock();
+		nht = rcu_dereference(tbl->nht);
 		ndc.ndtc_hash_rnd = nht->hash_rnd[0];
 		ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
-		rcu_read_unlock_bh();
+		rcu_read_unlock();
 
 		if (nla_put(skb, NDTA_CONFIG, sizeof(ndc), &ndc))
 			goto nla_put_failure;
@@ -2703,15 +2703,15 @@ static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
 	if (filter->dev_idx || filter->master_idx)
 		flags |= NLM_F_DUMP_FILTERED;
 
-	rcu_read_lock_bh();
-	nht = rcu_dereference_bh(tbl->nht);
+	rcu_read_lock();
+	nht = rcu_dereference(tbl->nht);
 
 	for (h = s_h; h < (1 << nht->hash_shift); h++) {
 		if (h > s_h)
 			s_idx = 0;
-		for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0;
+		for (n = rcu_dereference(nht->hash_buckets[h]), idx = 0;
 		     n != NULL;
-		     n = rcu_dereference_bh(n->next)) {
+		     n = rcu_dereference(n->next)) {
 			if (idx < s_idx || !net_eq(dev_net(n->dev), net))
 				goto next;
 			if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
@@ -2730,7 +2730,7 @@ next:
 	}
 	rc = skb->len;
 out:
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 	cb->args[1] = h;
 	cb->args[2] = idx;
 	return rc;
@@ -3075,20 +3075,20 @@ void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void
 	int chain;
 	struct neigh_hash_table *nht;
 
-	rcu_read_lock_bh();
-	nht = rcu_dereference_bh(tbl->nht);
+	rcu_read_lock();
+	nht = rcu_dereference(tbl->nht);
 
-	read_lock(&tbl->lock); /* avoid resizes */
+	read_lock_bh(&tbl->lock); /* avoid resizes */
 	for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
 		struct neighbour *n;
 
-		for (n = rcu_dereference_bh(nht->hash_buckets[chain]);
+		for (n = rcu_dereference(nht->hash_buckets[chain]);
 		     n != NULL;
-		     n = rcu_dereference_bh(n->next))
+		     n = rcu_dereference(n->next))
 			cb(n, cookie);
 	}
-	read_unlock(&tbl->lock);
-	rcu_read_unlock_bh();
+	read_unlock_bh(&tbl->lock);
+	rcu_read_unlock();
 }
 EXPORT_SYMBOL(neigh_for_each);
 
@@ -3138,7 +3138,7 @@ int neigh_xmit(int index, struct net_device *dev,
 		tbl = neigh_tables[index];
 		if (!tbl)
 			goto out;
-		rcu_read_lock_bh();
+		rcu_read_lock();
 		if (index == NEIGH_ARP_TABLE) {
 			u32 key = *((u32 *)addr);
 
@@ -3150,11 +3150,11 @@ int neigh_xmit(int index, struct net_device *dev,
 			neigh = __neigh_create(tbl, addr, dev, false);
 		err = PTR_ERR(neigh);
 		if (IS_ERR(neigh)) {
-			rcu_read_unlock_bh();
+			rcu_read_unlock();
 			goto out_kfree_skb;
 		}
 		err = neigh->output(neigh, skb);
-		rcu_read_unlock_bh();
+		rcu_read_unlock();
 	}
 	else if (index == NEIGH_LINK_TABLE) {
 		err = dev_hard_header(skb, dev, ntohs(skb->protocol),
@@ -3183,7 +3183,7 @@ static struct neighbour *neigh_get_first(struct seq_file *seq)
 
 	state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
 	for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
-		n = rcu_dereference_bh(nht->hash_buckets[bucket]);
+		n = rcu_dereference(nht->hash_buckets[bucket]);
 
 		while (n) {
 			if (!net_eq(dev_net(n->dev), net))
@@ -3201,7 +3201,7 @@ static struct neighbour *neigh_get_first(struct seq_file *seq)
 			if (READ_ONCE(n->nud_state) & ~NUD_NOARP)
 				break;
 next:
-			n = rcu_dereference_bh(n->next);
+			n = rcu_dereference(n->next);
 		}
 
 		if (n)
@@ -3225,7 +3225,7 @@ static struct neighbour *neigh_get_next(struct seq_file *seq,
 		if (v)
 			return n;
 	}
-	n = rcu_dereference_bh(n->next);
+	n = rcu_dereference(n->next);
 
 	while (1) {
 		while (n) {
@@ -3243,7 +3243,7 @@ static struct neighbour *neigh_get_next(struct seq_file *seq,
 			if (READ_ONCE(n->nud_state) & ~NUD_NOARP)
 				break;
 next:
-			n = rcu_dereference_bh(n->next);
+			n = rcu_dereference(n->next);
 		}
 
 		if (n)
@@ -3252,7 +3252,7 @@ next:
 		if (++state->bucket >= (1 << nht->hash_shift))
 			break;
 
-		n = rcu_dereference_bh(nht->hash_buckets[state->bucket]);
+		n = rcu_dereference(nht->hash_buckets[state->bucket]);
 	}
 
 	if (n && pos)
@@ -3354,7 +3354,7 @@ 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)
+	__acquires(rcu)
 {
 	struct neigh_seq_state *state = seq->private;
 
@@ -3362,9 +3362,9 @@ 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);
 
-	rcu_read_lock_bh();
-	state->nht = rcu_dereference_bh(tbl->nht);
-	read_lock(&tbl->lock);
+	rcu_read_lock();
+	state->nht = rcu_dereference(tbl->nht);
+	read_lock_bh(&tbl->lock);
 
 	return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
 }
@@ -3399,13 +3399,13 @@ EXPORT_SYMBOL(neigh_seq_next);
 
 void neigh_seq_stop(struct seq_file *seq, void *v)
 	__releases(tbl->lock)
-	__releases(rcu_bh)
+	__releases(rcu)
 {
 	struct neigh_seq_state *state = seq->private;
 	struct neigh_table *tbl = state->tbl;
 
-	read_unlock(&tbl->lock);
-	rcu_read_unlock_bh();
+	read_unlock_bh(&tbl->lock);
+	rcu_read_unlock();
 }
 EXPORT_SYMBOL(neigh_seq_stop);