[ewg] Re: Continue of "defer skb_orphan() until irqs enabled"

Roland Dreier rdreier at cisco.com
Fri Sep 26 13:19:00 PDT 2008


How about this?  Instead of trying to rely on some complicated and
fragile reasoning about when some race might occur, let's just do what
we want to do anyway and get rid of LLTX.  We change from priv->tx_lock
(taken with IRQ disabling) to netif_tx_lock (taken on with
BH-disabling).  And then we can keep the skb_orphan in the place it is,
since our xmit routine runs with IRQs enabled.

Most of this patch is just compensating for the fact that the tx_lock
regions are now IRQ-enabled, and so we have to convert places that take
priv->lock to disable IRQs too.

If we could change ipoib_cm_rx_event_handler to not need priv->lock,
then we could change priv->lock to a BH-disabling lock too and simplify
things a bit further.

I've tested this patch some in both datagram and connected mode with a
kernel with lockdep and other debugging enabled, so it is at least
somewhat sane.  However more stress testing would definitely be helpful
if we want to put this in 2.6.28.  Also it would be interesting to see
if there are any performance effects.

Thanks,
  Roland

---

 drivers/infiniband/ulp/ipoib/ipoib.h           |    8 +--
 drivers/infiniband/ulp/ipoib/ipoib_cm.c        |   88 ++++++++++++++----------
 drivers/infiniband/ulp/ipoib/ipoib_ib.c        |   30 ++++++--
 drivers/infiniband/ulp/ipoib/ipoib_main.c      |   68 ++++++++-----------
 drivers/infiniband/ulp/ipoib/ipoib_multicast.c |   31 ++++-----
 5 files changed, 118 insertions(+), 107 deletions(-)

diff --git a/drivers/infiniband/ulp/ipoib/ipoib.h b/drivers/infiniband/ulp/ipoib/ipoib.h
index 05eb41b..68ba5c3 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib.h
+++ b/drivers/infiniband/ulp/ipoib/ipoib.h
@@ -268,10 +268,9 @@ struct ipoib_lro {
 };
 
 /*
- * Device private locking: tx_lock protects members used in TX fast
- * path (and we use LLTX so upper layers don't do extra locking).
- * lock protects everything else.  lock nests inside of tx_lock (ie
- * tx_lock must be acquired first if needed).
+ * Device private locking: network stack tx_lock protects members used
+ * in TX fast path, lock protects everything else.  lock nests inside
+ * of tx_lock (ie tx_lock must be acquired first if needed).
  */
 struct ipoib_dev_priv {
 	spinlock_t lock;
@@ -320,7 +319,6 @@ struct ipoib_dev_priv {
 
 	struct ipoib_rx_buf *rx_ring;
 
-	spinlock_t	     tx_lock;
 	struct ipoib_tx_buf *tx_ring;
 	unsigned	     tx_head;
 	unsigned	     tx_tail;
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_cm.c b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
index 341ffed..7b14c2c 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_cm.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
@@ -786,7 +786,8 @@ void ipoib_cm_handle_tx_wc(struct net_device *dev, struct ib_wc *wc)
 
 	dev_kfree_skb_any(tx_req->skb);
 
-	spin_lock_irqsave(&priv->tx_lock, flags);
+	netif_tx_lock(dev);
+
 	++tx->tx_tail;
 	if (unlikely(--priv->tx_outstanding == ipoib_sendq_size >> 1) &&
 	    netif_queue_stopped(dev) &&
@@ -801,7 +802,7 @@ void ipoib_cm_handle_tx_wc(struct net_device *dev, struct ib_wc *wc)
 			   "(status=%d, wrid=%d vend_err %x)\n",
 			   wc->status, wr_id, wc->vendor_err);
 
-		spin_lock(&priv->lock);
+		spin_lock_irqsave(&priv->lock, flags);
 		neigh = tx->neigh;
 
 		if (neigh) {
@@ -821,10 +822,10 @@ void ipoib_cm_handle_tx_wc(struct net_device *dev, struct ib_wc *wc)
 
 		clear_bit(IPOIB_FLAG_OPER_UP, &tx->flags);
 
-		spin_unlock(&priv->lock);
+		spin_unlock_irqrestore(&priv->lock, flags);
 	}
 
-	spin_unlock_irqrestore(&priv->tx_lock, flags);
+	netif_tx_unlock(dev);
 }
 
 int ipoib_cm_dev_open(struct net_device *dev)
@@ -1149,7 +1150,6 @@ static void ipoib_cm_tx_destroy(struct ipoib_cm_tx *p)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(p->dev);
 	struct ipoib_cm_tx_buf *tx_req;
-	unsigned long flags;
 	unsigned long begin;
 
 	ipoib_dbg(priv, "Destroy active connection 0x%x head 0x%x tail 0x%x\n",
@@ -1180,12 +1180,12 @@ timeout:
 				    DMA_TO_DEVICE);
 		dev_kfree_skb_any(tx_req->skb);
 		++p->tx_tail;
-		spin_lock_irqsave(&priv->tx_lock, flags);
+		netif_tx_lock_bh(p->dev);
 		if (unlikely(--priv->tx_outstanding == ipoib_sendq_size >> 1) &&
 		    netif_queue_stopped(p->dev) &&
 		    test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags))
 			netif_wake_queue(p->dev);
-		spin_unlock_irqrestore(&priv->tx_lock, flags);
+		netif_tx_unlock_bh(p->dev);
 	}
 
 	if (p->qp)
@@ -1202,6 +1202,7 @@ 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) {
@@ -1220,8 +1221,8 @@ 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_irq(&priv->tx_lock);
-		spin_lock(&priv->lock);
+		netif_tx_lock_bh(dev);
+		spin_lock_irqsave(&priv->lock, flags);
 		neigh = tx->neigh;
 
 		if (neigh) {
@@ -1239,8 +1240,8 @@ static int ipoib_cm_tx_handler(struct ib_cm_id *cm_id,
 			queue_work(ipoib_workqueue, &priv->cm.reap_task);
 		}
 
-		spin_unlock(&priv->lock);
-		spin_unlock_irq(&priv->tx_lock);
+		spin_unlock_irqrestore(&priv->lock, flags);
+		netif_tx_unlock_bh(dev);
 		break;
 	default:
 		break;
@@ -1294,19 +1295,24 @@ static void ipoib_cm_tx_start(struct work_struct *work)
 	struct ib_sa_path_rec pathrec;
 	u32 qpn;
 
-	spin_lock_irqsave(&priv->tx_lock, flags);
-	spin_lock(&priv->lock);
+	netif_tx_lock_bh(dev);
+	spin_lock_irqsave(&priv->lock, flags);
+
 	while (!list_empty(&priv->cm.start_list)) {
 		p = list_entry(priv->cm.start_list.next, typeof(*p), list);
 		list_del_init(&p->list);
 		neigh = p->neigh;
 		qpn = IPOIB_QPN(neigh->neighbour->ha);
 		memcpy(&pathrec, &p->path->pathrec, sizeof pathrec);
-		spin_unlock(&priv->lock);
-		spin_unlock_irqrestore(&priv->tx_lock, flags);
+
+		spin_unlock_irqrestore(&priv->lock, flags);
+		netif_tx_unlock_bh(dev);
+
 		ret = ipoib_cm_tx_init(p, qpn, &pathrec);
-		spin_lock_irqsave(&priv->tx_lock, flags);
-		spin_lock(&priv->lock);
+
+		netif_tx_lock_bh(dev);
+		spin_lock_irqsave(&priv->lock, flags);
+
 		if (ret) {
 			neigh = p->neigh;
 			if (neigh) {
@@ -1320,44 +1326,52 @@ static void ipoib_cm_tx_start(struct work_struct *work)
 			kfree(p);
 		}
 	}
-	spin_unlock(&priv->lock);
-	spin_unlock_irqrestore(&priv->tx_lock, flags);
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+	netif_tx_unlock_bh(dev);
 }
 
 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 net_device *dev = priv->dev;
 	struct ipoib_cm_tx *p;
+	unsigned long flags;
+
+	netif_tx_lock_bh(dev);
+	spin_lock_irqsave(&priv->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_irq(&priv->tx_lock);
+		spin_unlock_irqrestore(&priv->lock, flags);
+		netif_tx_unlock_bh(dev);
 		ipoib_cm_tx_destroy(p);
-		spin_lock_irq(&priv->tx_lock);
-		spin_lock(&priv->lock);
+		netif_tx_lock_bh(dev);
+		spin_lock_irqsave(&priv->lock, flags);
 	}
-	spin_unlock(&priv->lock);
-	spin_unlock_irq(&priv->tx_lock);
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+	netif_tx_unlock_bh(dev);
 }
 
 static void ipoib_cm_skb_reap(struct work_struct *work)
 {
 	struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
 						   cm.skb_task);
+	struct net_device *dev = priv->dev;
 	struct sk_buff *skb;
-
+	unsigned long flags;
 	unsigned mtu = priv->mcast_mtu;
 
-	spin_lock_irq(&priv->tx_lock);
-	spin_lock(&priv->lock);
+	netif_tx_lock_bh(dev);
+	spin_lock_irqsave(&priv->lock, flags);
+
 	while ((skb = skb_dequeue(&priv->cm.skb_queue))) {
-		spin_unlock(&priv->lock);
-		spin_unlock_irq(&priv->tx_lock);
+		spin_unlock_irqrestore(&priv->lock, flags);
+		netif_tx_unlock_bh(dev);
+
 		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)
@@ -1365,11 +1379,13 @@ static void ipoib_cm_skb_reap(struct work_struct *work)
 			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, priv->dev);
 #endif
 		dev_kfree_skb_any(skb);
-		spin_lock_irq(&priv->tx_lock);
-		spin_lock(&priv->lock);
+
+		netif_tx_lock_bh(dev);
+		spin_lock_irqsave(&priv->lock, flags);
 	}
-	spin_unlock(&priv->lock);
-	spin_unlock_irq(&priv->tx_lock);
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+	netif_tx_unlock_bh(dev);
 }
 
 void ipoib_cm_skb_too_long(struct net_device *dev, struct sk_buff *skb,
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_ib.c b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
index 66cafa2..0e748ae 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_ib.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
@@ -468,21 +468,22 @@ void ipoib_ib_completion(struct ib_cq *cq, void *dev_ptr)
 static void drain_tx_cq(struct net_device *dev)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
-	unsigned long flags;
 
-	spin_lock_irqsave(&priv->tx_lock, flags);
+	netif_tx_lock(dev);
 	while (poll_tx(priv))
 		; /* nothing */
 
 	if (netif_queue_stopped(dev))
 		mod_timer(&priv->poll_timer, jiffies + 1);
 
-	spin_unlock_irqrestore(&priv->tx_lock, flags);
+	netif_tx_unlock(dev);
 }
 
 void ipoib_send_comp_handler(struct ib_cq *cq, void *dev_ptr)
 {
-	drain_tx_cq((struct net_device *)dev_ptr);
+	struct ipoib_dev_priv *priv = netdev_priv(dev_ptr);
+
+	mod_timer(&priv->poll_timer, jiffies);
 }
 
 static inline int post_send(struct ipoib_dev_priv *priv,
@@ -614,17 +615,20 @@ static void __ipoib_reap_ah(struct net_device *dev)
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	struct ipoib_ah *ah, *tah;
 	LIST_HEAD(remove_list);
+	unsigned long flags;
+
+	netif_tx_lock_bh(dev);
+	spin_lock_irqsave(&priv->lock, flags);
 
-	spin_lock_irq(&priv->tx_lock);
-	spin_lock(&priv->lock);
 	list_for_each_entry_safe(ah, tah, &priv->dead_ahs, list)
 		if ((int) priv->tx_tail - (int) ah->last_send >= 0) {
 			list_del(&ah->list);
 			ib_destroy_ah(ah->ah);
 			kfree(ah);
 		}
-	spin_unlock(&priv->lock);
-	spin_unlock_irq(&priv->tx_lock);
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+	netif_tx_unlock_bh(dev);
 }
 
 void ipoib_reap_ah(struct work_struct *work)
@@ -761,6 +765,14 @@ void ipoib_drain_cq(struct net_device *dev)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	int i, n;
+
+	/*
+	 * We call completion handling routines that expect to be
+	 * called from the BH-disabled NAPI poll context, so disable
+	 * BHs here too.
+	 */
+	local_bh_disable();
+
 	do {
 		n = ib_poll_cq(priv->recv_cq, IPOIB_NUM_WC, priv->ibwc);
 		for (i = 0; i < n; ++i) {
@@ -784,6 +796,8 @@ void ipoib_drain_cq(struct net_device *dev)
 
 	while (poll_tx(priv))
 		; /* nothing */
+
+	local_bh_enable();
 }
 
 int ipoib_ib_dev_stop(struct net_device *dev, int flush)
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index e9ca3cb..c0ee514 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -373,9 +373,10 @@ void ipoib_flush_paths(struct net_device *dev)
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	struct ipoib_path *path, *tp;
 	LIST_HEAD(remove_list);
+	unsigned long flags;
 
-	spin_lock_irq(&priv->tx_lock);
-	spin_lock(&priv->lock);
+	netif_tx_lock_bh(dev);
+	spin_lock_irqsave(&priv->lock, flags);
 
 	list_splice_init(&priv->path_list, &remove_list);
 
@@ -385,15 +386,16 @@ void ipoib_flush_paths(struct net_device *dev)
 	list_for_each_entry_safe(path, tp, &remove_list, list) {
 		if (path->query)
 			ib_sa_cancel_query(path->query_id, path->query);
-		spin_unlock(&priv->lock);
-		spin_unlock_irq(&priv->tx_lock);
+		spin_unlock_irqrestore(&priv->lock, flags);
+		netif_tx_unlock_bh(dev);
 		wait_for_completion(&path->done);
 		path_free(dev, path);
-		spin_lock_irq(&priv->tx_lock);
-		spin_lock(&priv->lock);
+		netif_tx_lock_bh(dev);
+		spin_lock_irqsave(&priv->lock, flags);
 	}
-	spin_unlock(&priv->lock);
-	spin_unlock_irq(&priv->tx_lock);
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+	netif_tx_unlock_bh(dev);
 }
 
 static void path_rec_completion(int status,
@@ -555,6 +557,7 @@ static void neigh_add_path(struct sk_buff *skb, struct net_device *dev)
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	struct ipoib_path *path;
 	struct ipoib_neigh *neigh;
+	unsigned long flags;
 
 	neigh = ipoib_neigh_alloc(skb->dst->neighbour, skb->dev);
 	if (!neigh) {
@@ -563,11 +566,7 @@ static void neigh_add_path(struct sk_buff *skb, struct net_device *dev)
 		return;
 	}
 
-	/*
-	 * We can only be called from ipoib_start_xmit, so we're
-	 * inside tx_lock -- no need to save/restore flags.
-	 */
-	spin_lock(&priv->lock);
+	spin_lock_irqsave(&priv->lock, flags);
 
 	path = __path_find(dev, skb->dst->neighbour->ha + 4);
 	if (!path) {
@@ -614,7 +613,7 @@ static void neigh_add_path(struct sk_buff *skb, struct net_device *dev)
 		__skb_queue_tail(&neigh->queue, skb);
 	}
 
-	spin_unlock(&priv->lock);
+	spin_unlock_irqrestore(&priv->lock, flags);
 	return;
 
 err_list:
@@ -626,7 +625,7 @@ err_drop:
 	++dev->stats.tx_dropped;
 	dev_kfree_skb_any(skb);
 
-	spin_unlock(&priv->lock);
+	spin_unlock_irqrestore(&priv->lock, flags);
 }
 
 static void ipoib_path_lookup(struct sk_buff *skb, struct net_device *dev)
@@ -650,12 +649,9 @@ static void unicast_arp_send(struct sk_buff *skb, struct net_device *dev,
 {
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	struct ipoib_path *path;
+	unsigned long flags;
 
-	/*
-	 * We can only be called from ipoib_start_xmit, so we're
-	 * inside tx_lock -- no need to save/restore flags.
-	 */
-	spin_lock(&priv->lock);
+	spin_lock_irqsave(&priv->lock, flags);
 
 	path = __path_find(dev, phdr->hwaddr + 4);
 	if (!path || !path->valid) {
@@ -667,7 +663,7 @@ static void unicast_arp_send(struct sk_buff *skb, struct net_device *dev,
 			__skb_queue_tail(&path->queue, skb);
 
 			if (path_rec_start(dev, path)) {
-				spin_unlock(&priv->lock);
+				spin_unlock_irqrestore(&priv->lock, flags);
 				path_free(dev, path);
 				return;
 			} else
@@ -677,7 +673,7 @@ static void unicast_arp_send(struct sk_buff *skb, struct net_device *dev,
 			dev_kfree_skb_any(skb);
 		}
 
-		spin_unlock(&priv->lock);
+		spin_unlock_irqrestore(&priv->lock, flags);
 		return;
 	}
 
@@ -696,7 +692,7 @@ static void unicast_arp_send(struct sk_buff *skb, struct net_device *dev,
 		dev_kfree_skb_any(skb);
 	}
 
-	spin_unlock(&priv->lock);
+	spin_unlock_irqrestore(&priv->lock, flags);
 }
 
 static int ipoib_start_xmit(struct sk_buff *skb, struct net_device *dev)
@@ -705,13 +701,10 @@ static int ipoib_start_xmit(struct sk_buff *skb, struct net_device *dev)
 	struct ipoib_neigh *neigh;
 	unsigned long flags;
 
-	if (unlikely(!spin_trylock_irqsave(&priv->tx_lock, flags)))
-		return NETDEV_TX_LOCKED;
-
 	if (likely(skb->dst && skb->dst->neighbour)) {
 		if (unlikely(!*to_ipoib_neigh(skb->dst->neighbour))) {
 			ipoib_path_lookup(skb, dev);
-			goto out;
+			return NETDEV_TX_OK;
 		}
 
 		neigh = *to_ipoib_neigh(skb->dst->neighbour);
@@ -721,7 +714,7 @@ static int ipoib_start_xmit(struct sk_buff *skb, struct net_device *dev)
 					    skb->dst->neighbour->ha + 4,
 					    sizeof(union ib_gid))) ||
 					 (neigh->dev != dev))) {
-				spin_lock(&priv->lock);
+				spin_lock_irqsave(&priv->lock, flags);
 				/*
 				 * It's safe to call ipoib_put_ah() inside
 				 * priv->lock here, because we know that
@@ -732,25 +725,25 @@ static int ipoib_start_xmit(struct sk_buff *skb, struct net_device *dev)
 				ipoib_put_ah(neigh->ah);
 				list_del(&neigh->list);
 				ipoib_neigh_free(dev, neigh);
-				spin_unlock(&priv->lock);
+				spin_unlock_irqrestore(&priv->lock, flags);
 				ipoib_path_lookup(skb, dev);
-				goto out;
+				return NETDEV_TX_OK;
 			}
 
 		if (ipoib_cm_get(neigh)) {
 			if (ipoib_cm_up(neigh)) {
 				ipoib_cm_send(dev, skb, ipoib_cm_get(neigh));
-				goto out;
+				return NETDEV_TX_OK;
 			}
 		} else if (neigh->ah) {
 			ipoib_send(dev, skb, neigh->ah, IPOIB_QPN(skb->dst->neighbour->ha));
-			goto out;
+			return NETDEV_TX_OK;
 		}
 
 		if (skb_queue_len(&neigh->queue) < IPOIB_MAX_PATH_REC_QUEUE) {
-			spin_lock(&priv->lock);
+			spin_lock_irqsave(&priv->lock, flags);
 			__skb_queue_tail(&neigh->queue, skb);
-			spin_unlock(&priv->lock);
+			spin_unlock_irqrestore(&priv->lock, flags);
 		} else {
 			++dev->stats.tx_dropped;
 			dev_kfree_skb_any(skb);
@@ -779,16 +772,13 @@ static int ipoib_start_xmit(struct sk_buff *skb, struct net_device *dev)
 					   IPOIB_GID_RAW_ARG(phdr->hwaddr + 4));
 				dev_kfree_skb_any(skb);
 				++dev->stats.tx_dropped;
-				goto out;
+				return NETDEV_TX_OK;
 			}
 
 			unicast_arp_send(skb, dev, phdr);
 		}
 	}
 
-out:
-	spin_unlock_irqrestore(&priv->tx_lock, flags);
-
 	return NETDEV_TX_OK;
 }
 
@@ -1052,7 +1042,6 @@ static void ipoib_setup(struct net_device *dev)
 	dev->type		 = ARPHRD_INFINIBAND;
 	dev->tx_queue_len	 = ipoib_sendq_size * 2;
 	dev->features		 = (NETIF_F_VLAN_CHALLENGED	|
-				    NETIF_F_LLTX		|
 				    NETIF_F_HIGHDMA);
 
 	memcpy(dev->broadcast, ipv4_bcast_addr, INFINIBAND_ALEN);
@@ -1064,7 +1053,6 @@ static void ipoib_setup(struct net_device *dev)
 	ipoib_lro_setup(priv);
 
 	spin_lock_init(&priv->lock);
-	spin_lock_init(&priv->tx_lock);
 
 	mutex_init(&priv->vlan_mutex);
 
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
index aae2862..d9d1223 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
@@ -69,14 +69,13 @@ static void ipoib_mcast_free(struct ipoib_mcast *mcast)
 	struct net_device *dev = mcast->dev;
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	struct ipoib_neigh *neigh, *tmp;
-	unsigned long flags;
 	int tx_dropped = 0;
 
 	ipoib_dbg_mcast(netdev_priv(dev),
 			"deleting multicast group " IPOIB_GID_FMT "\n",
 			IPOIB_GID_ARG(mcast->mcmember.mgid));
 
-	spin_lock_irqsave(&priv->lock, flags);
+	spin_lock_irq(&priv->lock);
 
 	list_for_each_entry_safe(neigh, tmp, &mcast->neigh_list, list) {
 		/*
@@ -90,7 +89,7 @@ static void ipoib_mcast_free(struct ipoib_mcast *mcast)
 		ipoib_neigh_free(dev, neigh);
 	}
 
-	spin_unlock_irqrestore(&priv->lock, flags);
+	spin_unlock_irq(&priv->lock);
 
 	if (mcast->ah)
 		ipoib_put_ah(mcast->ah);
@@ -100,9 +99,9 @@ static void ipoib_mcast_free(struct ipoib_mcast *mcast)
 		dev_kfree_skb_any(skb_dequeue(&mcast->pkt_queue));
 	}
 
-	spin_lock_irqsave(&priv->tx_lock, flags);
+	netif_tx_lock_bh(dev);
 	dev->stats.tx_dropped += tx_dropped;
-	spin_unlock_irqrestore(&priv->tx_lock, flags);
+	netif_tx_unlock_bh(dev);
 
 	kfree(mcast);
 }
@@ -259,10 +258,10 @@ static int ipoib_mcast_join_finish(struct ipoib_mcast *mcast,
 	}
 
 	/* actually send any queued packets */
-	spin_lock_irq(&priv->tx_lock);
+	netif_tx_lock_bh(dev);
 	while (!skb_queue_empty(&mcast->pkt_queue)) {
 		struct sk_buff *skb = skb_dequeue(&mcast->pkt_queue);
-		spin_unlock_irq(&priv->tx_lock);
+		netif_tx_unlock_bh(dev);
 
 		skb->dev = dev;
 
@@ -273,9 +272,9 @@ static int ipoib_mcast_join_finish(struct ipoib_mcast *mcast,
 
 		if (dev_queue_xmit(skb))
 			ipoib_warn(priv, "dev_queue_xmit failed to requeue packet\n");
-		spin_lock_irq(&priv->tx_lock);
+		netif_tx_lock_bh(dev);
 	}
-	spin_unlock_irq(&priv->tx_lock);
+	netif_tx_unlock_bh(dev);
 
 	return 0;
 }
@@ -286,7 +285,6 @@ ipoib_mcast_sendonly_join_complete(int status,
 {
 	struct ipoib_mcast *mcast = multicast->context;
 	struct net_device *dev = mcast->dev;
-	struct ipoib_dev_priv *priv = netdev_priv(dev);
 
 	/* We trap for port events ourselves. */
 	if (status == -ENETRESET)
@@ -302,12 +300,12 @@ ipoib_mcast_sendonly_join_complete(int status,
 					IPOIB_GID_ARG(mcast->mcmember.mgid), status);
 
 		/* Flush out any queued packets */
-		spin_lock_irq(&priv->tx_lock);
+		netif_tx_lock_bh(dev);
 		while (!skb_queue_empty(&mcast->pkt_queue)) {
 			++dev->stats.tx_dropped;
 			dev_kfree_skb_any(skb_dequeue(&mcast->pkt_queue));
 		}
-		spin_unlock_irq(&priv->tx_lock);
+		netif_tx_unlock_bh(dev);
 
 		/* Clear the busy flag so we try again */
 		status = test_and_clear_bit(IPOIB_MCAST_FLAG_BUSY,
@@ -662,12 +660,9 @@ void ipoib_mcast_send(struct net_device *dev, void *mgid, struct sk_buff *skb)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	struct ipoib_mcast *mcast;
+	unsigned long flags;
 
-	/*
-	 * We can only be called from ipoib_start_xmit, so we're
-	 * inside tx_lock -- no need to save/restore flags.
-	 */
-	spin_lock(&priv->lock);
+	spin_lock_irqsave(&priv->lock, flags);
 
 	if (!test_bit(IPOIB_FLAG_OPER_UP, &priv->flags)		||
 	    !priv->broadcast					||
@@ -738,7 +733,7 @@ out:
 	}
 
 unlock:
-	spin_unlock(&priv->lock);
+	spin_unlock_irqrestore(&priv->lock, flags);
 }
 
 void ipoib_mcast_dev_flush(struct net_device *dev)



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