net,rcu: convert call_rcu(tcf_common_free_rcu) to kfree_rcu()

The rcu callback tcf_common_free_rcu() just calls a kfree(),
so we use kfree_rcu() instead of the call_rcu(tcf_common_free_rcu).

Signed-off-by: Lai Jiangshan <[e-mail]>
Acked-by: David S. Miller <[e-mail]>
Signed-off-by: Paul E. McKenney <[e-mail]>
Reviewed-by: Josh Triplett <[e-mail]>

net/sched/act_api.c

···
 #include <net/act_api.h>
 #include <net/netlink.h>
 
-static void tcf_common_free_rcu(struct rcu_head *head)
-{
-	kfree(container_of(head, struct tcf_common, tcfc_rcu));
-}
-
 void tcf_hash_destroy(struct tcf_common *p, struct tcf_hashinfo *hinfo)
 {
 	unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
···
 			 * gen_estimator est_timer() might access p->tcfc_lock
 			 * or bstats, wait a RCU grace period before freeing p
 			 */
-			call_rcu(&p->tcfc_rcu, tcf_common_free_rcu);
+			kfree_rcu(p, tcfc_rcu);
 			return;
 		}
 	}