net/sched: Replace call_rcu_bh() and rcu_barrier_bh()

Now that call_rcu()'s callback is not invoked until after bh-disable
regions of code have completed (in addition to explicitly marked
RCU read-side critical sections), call_rcu() can be used in place
of call_rcu_bh().  Similarly, rcu_barrier() can be used in place o
frcu_barrier_bh().  This commit therefore makes these changes.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: <netdev@vger.kernel.org>

net/sched/sch_api.c

@@ -540,7 +540,7 @@ void qdisc_put_stab(struct qdisc_size_table *tab)
 
 	if (--tab->refcnt == 0) {
 		list_del(&tab->list);
-		call_rcu_bh(&tab->rcu, stab_kfree_rcu);
+		call_rcu(&tab->rcu, stab_kfree_rcu);
 	}
 }
 EXPORT_SYMBOL(qdisc_put_stab);

net/sched/sch_generic.c

@@ -1372,7 +1372,7 @@ void mini_qdisc_pair_swap(struct mini_Qdisc_pair *miniqp,
 	if (!tp_head) {
 		RCU_INIT_POINTER(*miniqp->p_miniq, NULL);
 		/* Wait for flying RCU callback before it is freed. */
-		rcu_barrier_bh();
+		rcu_barrier();
 		return;
 	}
 
@@ -1380,10 +1380,10 @@ void mini_qdisc_pair_swap(struct mini_Qdisc_pair *miniqp,
 		&miniqp->miniq1 : &miniqp->miniq2;
 
 	/* We need to make sure that readers won't see the miniq
-	 * we are about to modify. So wait until previous call_rcu_bh callback
+	 * we are about to modify. So wait until previous call_rcu callback
 	 * is done.
 	 */
-	rcu_barrier_bh();
+	rcu_barrier();
 	miniq->filter_list = tp_head;
 	rcu_assign_pointer(*miniqp->p_miniq, miniq);
 
@@ -1392,7 +1392,7 @@ void mini_qdisc_pair_swap(struct mini_Qdisc_pair *miniqp,
 		 * block potential new user of miniq_old until all readers
 		 * are not seeing it.
 		 */
-		call_rcu_bh(&miniq_old->rcu, mini_qdisc_rcu_func);
+		call_rcu(&miniq_old->rcu, mini_qdisc_rcu_func);
 }
 EXPORT_SYMBOL(mini_qdisc_pair_swap);