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

The rcu callback kfree_tid_tx() just calls a kfree(),
so we use kfree_rcu() instead of the call_rcu(kfree_tid_tx).
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: "David S. Miller" <davem@davemloft.net>

net/mac80211/agg-tx.c

@@ -136,14 +136,6 @@ void ieee80211_send_bar(struct ieee80211_sub_if_data *sdata, u8 *ra, u16 tid, u1
 	ieee80211_tx_skb(sdata, skb);
 }
 
-static void kfree_tid_tx(struct rcu_head *rcu_head)
-{
-	struct tid_ampdu_tx *tid_tx =
-	    container_of(rcu_head, struct tid_ampdu_tx, rcu_head);
-
-	kfree(tid_tx);
-}
-
 int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
 				    enum ieee80211_back_parties initiator,
 				    bool tx)
@@ -163,7 +155,7 @@ int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
 		/* not even started yet! */
 		rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], NULL);
 		spin_unlock_bh(&sta->lock);
-		call_rcu(&tid_tx->rcu_head, kfree_tid_tx);
+		kfree_rcu(tid_tx, rcu_head);
 		return 0;
 	}
 
@@ -322,7 +314,7 @@ void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
 		spin_unlock_bh(&sta->lock);
 
 		ieee80211_wake_queue_agg(local, tid);
-		call_rcu(&tid_tx->rcu_head, kfree_tid_tx);
+		kfree_rcu(tid_tx, rcu_head);
 		return;
 	}
 
@@ -701,7 +693,7 @@ void ieee80211_stop_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u8 tid)
 
 	ieee80211_agg_splice_finish(local, tid);
 
-	call_rcu(&tid_tx->rcu_head, kfree_tid_tx);
+	kfree_rcu(tid_tx, rcu_head);
 
  unlock_sta:
 	spin_unlock_bh(&sta->lock);