[PATCH net-next v4 3/6] Convert neigh_* seq_file functions to use hlist

[Gilad Naaman <gnaaman@drivenets.com>]

Convert seq_file-related neighbour functionality to use neighbour::hash
and the related for_each macro.

Signed-off-by: Gilad Naaman <gnaaman@drivenets.com>
---
 include/net/neighbour.h |  4 ++++
 net/core/neighbour.c    | 26 ++++++++++----------------
 2 files changed, 14 insertions(+), 16 deletions(-)

diff --git a/include/net/neighbour.h b/include/net/neighbour.h
index 2f4cb9e51364..7dc0d4d6a4a8 100644
--- a/include/net/neighbour.h
+++ b/include/net/neighbour.h
@@ -279,6 +279,10 @@ static inline void *neighbour_priv(const struct neighbour *n)
 extern const struct nla_policy nda_policy[];
 
 #define neigh_for_each(pos, head) hlist_for_each_entry(pos, head, hash)
+#define neigh_hlist_entry(n) hlist_entry_safe(n, struct neighbour, hash)
+#define neigh_first_rcu(bucket) \
+	neigh_hlist_entry(rcu_dereference(hlist_first_rcu(bucket)))
+
 
 static inline bool neigh_key_eq32(const struct neighbour *n, const void *pkey)
 {
diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index e91105a4c5ee..4bdf7649ca57 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -3207,25 +3207,21 @@ 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(nht->hash_buckets[bucket]);
-
-		while (n) {
+		neigh_for_each(n, &nht->hash_heads[bucket]) {
 			if (!net_eq(dev_net(n->dev), net))
-				goto next;
+				continue;
 			if (state->neigh_sub_iter) {
 				loff_t fakep = 0;
 				void *v;
 
 				v = state->neigh_sub_iter(state, n, &fakep);
 				if (!v)
-					goto next;
+					continue;
 			}
 			if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
 				break;
 			if (READ_ONCE(n->nud_state) & ~NUD_NOARP)
 				break;
-next:
-			n = rcu_dereference(n->next);
 		}
 
 		if (n)
@@ -3249,34 +3245,32 @@ static struct neighbour *neigh_get_next(struct seq_file *seq,
 		if (v)
 			return n;
 	}
-	n = rcu_dereference(n->next);
 
 	while (1) {
-		while (n) {
+		hlist_for_each_entry_continue_rcu(n, hash) {
 			if (!net_eq(dev_net(n->dev), net))
-				goto next;
+				continue;
 			if (state->neigh_sub_iter) {
 				void *v = state->neigh_sub_iter(state, n, pos);
 				if (v)
 					return n;
-				goto next;
+				continue;
 			}
 			if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
 				break;
 
 			if (READ_ONCE(n->nud_state) & ~NUD_NOARP)
 				break;
-next:
-			n = rcu_dereference(n->next);
 		}
 
 		if (n)
 			break;
 
-		if (++state->bucket >= (1 << nht->hash_shift))
-			break;
+		while (!n && ++state->bucket < (1 << nht->hash_shift))
+			n = neigh_first_rcu(&nht->hash_heads[state->bucket]);
 
-		n = rcu_dereference(nht->hash_buckets[state->bucket]);
+		if (!n)
+			break;
 	}
 
 	if (n && pos)
-- 
2.46.0