IPoIB: Use netif_tx_lock() and get rid of private tx_lock, LLTX
Currently, IPoIB is an LLTX driver that uses its own IRQ-disabling
tx_lock. Not only do we want to get rid of LLTX, this actually causes
problems because of the skb_orphan() done with this tx_lock held: some
skb destructors expect to be run with interrupts enabled.
The simplest fix for this is to get rid of the driver-private tx_lock
and stop using LLTX. We kill off priv->tx_lock and use
netif_tx_lock[_bh]() instead; the patch to do this is a tiny bit
tricky because we need to update places that take priv->lock inside
the tx_lock to disable IRQs, rather than relying on tx_lock having
already disabled IRQs.
Also, there are a couple of places where we need to disable BHs to
make sure we have a consistent context to call netif_tx_lock() (since
we no longer can use _irqsave() variants), and we also have to change
ipoib_send_comp_handler() to call drain_tx_cq() through a timer rather
than directly, because ipoib_send_comp_handler() runs in interrupt
context and drain_tx_cq() must run in BH context so it can call
netif_tx_lock().
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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 @@
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 @@
"(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 @@
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 @@
{
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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
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;
- spin_lock_irq(&priv->tx_lock);
- spin_lock(&priv->lock);
+ netif_tx_lock_bh(dev);
+ spin_lock_irqsave(&priv->lock, flags);
+
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 @@
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,