inetpeer: replace call_rcu by kfree_rcu for simple kmem_cache_free ca…

…llback

Since SLOB was removed and since
commit 6c6c47b ("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@inria.fr>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Link: https://patch.msgid.link/20241013201704.49576-4-Julia.Lawall@inria.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/ipv4/inetpeer.c

@@ -128,11 +128,6 @@ static struct inet_peer *lookup(const struct inetpeer_addr *daddr,
 	return NULL;
 }
 
-static void inetpeer_free_rcu(struct rcu_head *head)
-{
-	kmem_cache_free(peer_cachep, container_of(head, struct inet_peer, rcu));
-}
-
 /* perform garbage collect on all items stacked during a lookup */
 static void inet_peer_gc(struct inet_peer_base *base,
 			 struct inet_peer *gc_stack[],
@@ -168,7 +163,7 @@ static void inet_peer_gc(struct inet_peer_base *base,
 		if (p) {
 			rb_erase(&p->rb_node, &base->rb_root);
 			base->total--;
-			call_rcu(&p->rcu, inetpeer_free_rcu);
+			kfree_rcu(p, rcu);
 		}
 	}
 }
@@ -242,7 +237,7 @@ void inet_putpeer(struct inet_peer *p)
 	WRITE_ONCE(p->dtime, (__u32)jiffies);
 
 	if (refcount_dec_and_test(&p->refcnt))
-		call_rcu(&p->rcu, inetpeer_free_rcu);
+		kfree_rcu(p, rcu);
 }
 EXPORT_SYMBOL_GPL(inet_putpeer);