IPoIB/cm: spin_lock_irqsave() -> spin_lock_irq() replacements

There are quite a few places in ipoib_cm.c where we know IRQs are
enabled because we do something that sleeps in the same function, so
we can convert several occurrences of spin_lock_irqsave() to a plain
spin_lock_irq().  This cleans up the source a little and makes the
code smaller too:

add/remove: 0/0 grow/shrink: 1/5 up/down: 3/-51 (-48)
function                                     old     new   delta
ipoib_cm_tx_reap                             403     406      +3
ipoib_cm_stale_task                          146     145      -1
ipoib_cm_dev_stop                            173     172      -1
ipoib_cm_tx_handler                          964     956      -8
ipoib_cm_rx_handler                          956     937     -19
ipoib_cm_skb_reap                            212     190     -22
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/infiniband/ulp/ipoib/ipoib_cm.c

@@ -228,7 +228,6 @@ static int ipoib_cm_req_handler(struct ib_cm_id *cm_id, struct ib_cm_event *even
 	struct net_device *dev = cm_id->context;
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	struct ipoib_cm_rx *p;
-	unsigned long flags;
 	unsigned psn;
 	int ret;
 
@@ -257,9 +256,9 @@ static int ipoib_cm_req_handler(struct ib_cm_id *cm_id, struct ib_cm_event *even
 
 	cm_id->context = p;
 	p->jiffies = jiffies;
-	spin_lock_irqsave(&priv->lock, flags);
+	spin_lock_irq(&priv->lock);
 	list_add(&p->list, &priv->cm.passive_ids);
-	spin_unlock_irqrestore(&priv->lock, flags);
+	spin_unlock_irq(&priv->lock);
 	queue_delayed_work(ipoib_workqueue,
 			   &priv->cm.stale_task, IPOIB_CM_RX_DELAY);
 	return 0;
@@ -277,7 +276,6 @@ static int ipoib_cm_rx_handler(struct ib_cm_id *cm_id,
 {
 	struct ipoib_cm_rx *p;
 	struct ipoib_dev_priv *priv;
-	unsigned long flags;
 	int ret;
 
 	switch (event->event) {
@@ -290,14 +288,14 @@ static int ipoib_cm_rx_handler(struct ib_cm_id *cm_id,
 	case IB_CM_REJ_RECEIVED:
 		p = cm_id->context;
 		priv = netdev_priv(p->dev);
-		spin_lock_irqsave(&priv->lock, flags);
+		spin_lock_irq(&priv->lock);
 		if (list_empty(&p->list))
 			ret = 0; /* Connection is going away already. */
 		else {
 			list_del_init(&p->list);
 			ret = -ECONNRESET;
 		}
-		spin_unlock_irqrestore(&priv->lock, flags);
+		spin_unlock_irq(&priv->lock);
 		if (ret) {
 			ib_destroy_qp(p->qp);
 			kfree(p);
@@ -612,23 +610,22 @@ void ipoib_cm_dev_stop(struct net_device *dev)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	struct ipoib_cm_rx *p;
-	unsigned long flags;
 
 	if (!IPOIB_CM_SUPPORTED(dev->dev_addr))
 		return;
 
 	ib_destroy_cm_id(priv->cm.id);
-	spin_lock_irqsave(&priv->lock, flags);
+	spin_lock_irq(&priv->lock);
 	while (!list_empty(&priv->cm.passive_ids)) {
 		p = list_entry(priv->cm.passive_ids.next, typeof(*p), list);
 		list_del_init(&p->list);
-		spin_unlock_irqrestore(&priv->lock, flags);
+		spin_unlock_irq(&priv->lock);
 		ib_destroy_cm_id(p->id);
 		ib_destroy_qp(p->qp);
 		kfree(p);
-		spin_lock_irqsave(&priv->lock, flags);
+		spin_lock_irq(&priv->lock);
 	}
-	spin_unlock_irqrestore(&priv->lock, flags);
+	spin_unlock_irq(&priv->lock);
 
 	cancel_delayed_work(&priv->cm.stale_task);
 }
@@ -642,7 +639,6 @@ static int ipoib_cm_rep_handler(struct ib_cm_id *cm_id, struct ib_cm_event *even
 	struct ib_qp_attr qp_attr;
 	int qp_attr_mask, ret;
 	struct sk_buff *skb;
-	unsigned long flags;
 
 	p->mtu = be32_to_cpu(data->mtu);
 
@@ -680,12 +676,12 @@ static int ipoib_cm_rep_handler(struct ib_cm_id *cm_id, struct ib_cm_event *even
 
 	skb_queue_head_init(&skqueue);
 
-	spin_lock_irqsave(&priv->lock, flags);
+	spin_lock_irq(&priv->lock);
 	set_bit(IPOIB_FLAG_OPER_UP, &p->flags);
 	if (p->neigh)
 		while ((skb = __skb_dequeue(&p->neigh->queue)))
 			__skb_queue_tail(&skqueue, skb);
-	spin_unlock_irqrestore(&priv->lock, flags);
+	spin_unlock_irq(&priv->lock);
 
 	while ((skb = __skb_dequeue(&skqueue))) {
 		skb->dev = p->dev;
@@ -895,7 +891,6 @@ static int ipoib_cm_tx_handler(struct ib_cm_id *cm_id,
 	struct ipoib_dev_priv *priv = netdev_priv(tx->dev);
 	struct net_device *dev = priv->dev;
 	struct ipoib_neigh *neigh;
-	unsigned long flags;
 	int ret;
 
 	switch (event->event) {
@@ -914,7 +909,7 @@ static int ipoib_cm_tx_handler(struct ib_cm_id *cm_id,
 	case IB_CM_REJ_RECEIVED:
 	case IB_CM_TIMEWAIT_EXIT:
 		ipoib_dbg(priv, "CM error %d.\n", event->event);
-		spin_lock_irqsave(&priv->tx_lock, flags);
+		spin_lock_irq(&priv->tx_lock);
 		spin_lock(&priv->lock);
 		neigh = tx->neigh;
 
@@ -934,7 +929,7 @@ static int ipoib_cm_tx_handler(struct ib_cm_id *cm_id,
 		}
 
 		spin_unlock(&priv->lock);
-		spin_unlock_irqrestore(&priv->tx_lock, flags);
+		spin_unlock_irq(&priv->tx_lock);
 		break;
 	default:
 		break;
@@ -1023,21 +1018,20 @@ static void ipoib_cm_tx_reap(struct work_struct *work)
 	struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
 						   cm.reap_task);
 	struct ipoib_cm_tx *p;
-	unsigned long flags;
 
-	spin_lock_irqsave(&priv->tx_lock, flags);
+	spin_lock_irq(&priv->tx_lock);
 	spin_lock(&priv->lock);
 	while (!list_empty(&priv->cm.reap_list)) {
 		p = list_entry(priv->cm.reap_list.next, typeof(*p), list);
 		list_del(&p->list);
 		spin_unlock(&priv->lock);
-		spin_unlock_irqrestore(&priv->tx_lock, flags);
+		spin_unlock_irq(&priv->tx_lock);
 		ipoib_cm_tx_destroy(p);
-		spin_lock_irqsave(&priv->tx_lock, flags);
+		spin_lock_irq(&priv->tx_lock);
 		spin_lock(&priv->lock);
 	}
 	spin_unlock(&priv->lock);
-	spin_unlock_irqrestore(&priv->tx_lock, flags);
+	spin_unlock_irq(&priv->tx_lock);
 }
 
 static void ipoib_cm_skb_reap(struct work_struct *work)
@@ -1046,15 +1040,14 @@ static void ipoib_cm_skb_reap(struct work_struct *work)
 						   cm.skb_task);
 	struct net_device *dev = priv->dev;
 	struct sk_buff *skb;
-	unsigned long flags;
 
 	unsigned mtu = priv->mcast_mtu;
 
-	spin_lock_irqsave(&priv->tx_lock, flags);
+	spin_lock_irq(&priv->tx_lock);
 	spin_lock(&priv->lock);
 	while ((skb = skb_dequeue(&priv->cm.skb_queue))) {
 		spin_unlock(&priv->lock);
-		spin_unlock_irqrestore(&priv->tx_lock, flags);
+		spin_unlock_irq(&priv->tx_lock);
 		if (skb->protocol == htons(ETH_P_IP))
 			icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
@@ -1062,11 +1055,11 @@ static void ipoib_cm_skb_reap(struct work_struct *work)
 			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
 #endif
 		dev_kfree_skb_any(skb);
-		spin_lock_irqsave(&priv->tx_lock, flags);
+		spin_lock_irq(&priv->tx_lock);
 		spin_lock(&priv->lock);
 	}
 	spin_unlock(&priv->lock);
-	spin_unlock_irqrestore(&priv->tx_lock, flags);
+	spin_unlock_irq(&priv->tx_lock);
 }
 
 void ipoib_cm_skb_too_long(struct net_device* dev, struct sk_buff *skb,
@@ -1088,9 +1081,8 @@ static void ipoib_cm_stale_task(struct work_struct *work)
 	struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
 						   cm.stale_task.work);
 	struct ipoib_cm_rx *p;
-	unsigned long flags;
 
-	spin_lock_irqsave(&priv->lock, flags);
+	spin_lock_irq(&priv->lock);
 	while (!list_empty(&priv->cm.passive_ids)) {
 		/* List if sorted by LRU, start from tail,
 		 * stop when we see a recently used entry */
@@ -1098,13 +1090,13 @@ static void ipoib_cm_stale_task(struct work_struct *work)
 		if (time_before_eq(jiffies, p->jiffies + IPOIB_CM_RX_TIMEOUT))
 			break;
 		list_del_init(&p->list);
-		spin_unlock_irqrestore(&priv->lock, flags);
+		spin_unlock_irq(&priv->lock);
 		ib_destroy_cm_id(p->id);
 		ib_destroy_qp(p->qp);
 		kfree(p);
-		spin_lock_irqsave(&priv->lock, flags);
+		spin_lock_irq(&priv->lock);
 	}
-	spin_unlock_irqrestore(&priv->lock, flags);
+	spin_unlock_irq(&priv->lock);
 }