[PATCH net-next 9/9] netfilter: replace call_rcu by kfree_rcu for simple kmem_cache_free callback

[Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>]

From: Julia Lawall <Julia.Lawall@xxxxxxxx>

Since SLOB was removed and since
commit 6c6c47b063b5 ("mm, slab: call kvfree_rcu_barrier() from kmem_cache_destroy()"),
it is not necessary to use call_rcu when the callback only performs
kmem_cache_free. Use kfree_rcu() directly.

The changes were made using Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@xxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
 net/netfilter/nf_conncount.c        | 10 +---------
 net/netfilter/nf_conntrack_expect.c | 10 +---------
 net/netfilter/xt_hashlimit.c        |  9 +--------
 3 files changed, 3 insertions(+), 26 deletions(-)

diff --git a/net/netfilter/nf_conncount.c b/net/netfilter/nf_conncount.c
index 4890af4dc263..6a7a6c2d6ebc 100644
--- a/net/netfilter/nf_conncount.c
+++ b/net/netfilter/nf_conncount.c
@@ -275,14 +275,6 @@ bool nf_conncount_gc_list(struct net *net,
 }
 EXPORT_SYMBOL_GPL(nf_conncount_gc_list);
 
-static void __tree_nodes_free(struct rcu_head *h)
-{
-	struct nf_conncount_rb *rbconn;
-
-	rbconn = container_of(h, struct nf_conncount_rb, rcu_head);
-	kmem_cache_free(conncount_rb_cachep, rbconn);
-}
-
 /* caller must hold tree nf_conncount_locks[] lock */
 static void tree_nodes_free(struct rb_root *root,
 			    struct nf_conncount_rb *gc_nodes[],
@@ -295,7 +287,7 @@ static void tree_nodes_free(struct rb_root *root,
 		spin_lock(&rbconn->list.list_lock);
 		if (!rbconn->list.count) {
 			rb_erase(&rbconn->node, root);
-			call_rcu(&rbconn->rcu_head, __tree_nodes_free);
+			kfree_rcu(rbconn, rcu_head);
 		}
 		spin_unlock(&rbconn->list.list_lock);
 	}
diff --git a/net/netfilter/nf_conntrack_expect.c b/net/netfilter/nf_conntrack_expect.c
index 21fa550966f0..9dcaef6f3663 100644
--- a/net/netfilter/nf_conntrack_expect.c
+++ b/net/netfilter/nf_conntrack_expect.c
@@ -367,18 +367,10 @@ void nf_ct_expect_init(struct nf_conntrack_expect *exp, unsigned int class,
 }
 EXPORT_SYMBOL_GPL(nf_ct_expect_init);
 
-static void nf_ct_expect_free_rcu(struct rcu_head *head)
-{
-	struct nf_conntrack_expect *exp;
-
-	exp = container_of(head, struct nf_conntrack_expect, rcu);
-	kmem_cache_free(nf_ct_expect_cachep, exp);
-}
-
 void nf_ct_expect_put(struct nf_conntrack_expect *exp)
 {
 	if (refcount_dec_and_test(&exp->use))
-		call_rcu(&exp->rcu, nf_ct_expect_free_rcu);
+		kfree_rcu(exp, rcu);
 }
 EXPORT_SYMBOL_GPL(nf_ct_expect_put);
 
diff --git a/net/netfilter/xt_hashlimit.c b/net/netfilter/xt_hashlimit.c
index 0859b8f76764..c2b9b954eb53 100644
--- a/net/netfilter/xt_hashlimit.c
+++ b/net/netfilter/xt_hashlimit.c
@@ -256,18 +256,11 @@ dsthash_alloc_init(struct xt_hashlimit_htable *ht,
 	return ent;
 }
 
-static void dsthash_free_rcu(struct rcu_head *head)
-{
-	struct dsthash_ent *ent = container_of(head, struct dsthash_ent, rcu);
-
-	kmem_cache_free(hashlimit_cachep, ent);
-}
-
 static inline void
 dsthash_free(struct xt_hashlimit_htable *ht, struct dsthash_ent *ent)
 {
 	hlist_del_rcu(&ent->node);
-	call_rcu(&ent->rcu, dsthash_free_rcu);
+	kfree_rcu(ent, rcu);
 	ht->count--;
 }
 static void htable_gc(struct work_struct *work);
-- 
2.30.2