net: bridge: replace call_rcu by kfree_rcu for simple kmem_cache_free callback

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 <[email protected]>
Acked-by: Nikolay Aleksandrov <[email protected]>
Acked-by: Paul E. McKenney <[email protected]>
Acked-by: Vlastimil Babka <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: JuliaLawall

net/bridge/br_fdb.c

@@ -73,13 +73,6 @@ static inline int has_expired(const struct net_bridge *br,
 	       time_before_eq(fdb->updated + hold_time(br), jiffies);
 }
 
-static void fdb_rcu_free(struct rcu_head *head)
-{
-	struct net_bridge_fdb_entry *ent
-		= container_of(head, struct net_bridge_fdb_entry, rcu);
-	kmem_cache_free(br_fdb_cache, ent);
-}
-
 static int fdb_to_nud(const struct net_bridge *br,
 		      const struct net_bridge_fdb_entry *fdb)
 {
@@ -329,7 +322,7 @@ static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f,
 	if (test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED, &f->flags))
 		atomic_dec(&br->fdb_n_learned);
 	fdb_notify(br, f, RTM_DELNEIGH, swdev_notify);
-	call_rcu(&f->rcu, fdb_rcu_free);
+	kfree_rcu(f, rcu);
 }
 
 /* Delete a local entry if no other port had the same address.