be2net: NCSI FW section should be properly updated with ethtool for BE3

[cascardo/linux.git] / drivers / net / ntb_netdev.c

diff --git a/drivers/net/ntb_netdev.c b/drivers/net/ntb_netdev.c
index d8757bf..a9acf71 100644 (file)
--- a/drivers/net/ntb_netdev.c
+++ b/drivers/net/ntb_netdev.c
@@ -61,11 +61,21 @@ MODULE_VERSION(NTB_NETDEV_VER);
 MODULE_LICENSE("Dual BSD/GPL");
 MODULE_AUTHOR("Intel Corporation");
 
+/* Time in usecs for tx resource reaper */
+static unsigned int tx_time = 1;
+
+/* Number of descriptors to free before resuming tx */
+static unsigned int tx_start = 10;
+
+/* Number of descriptors still available before stop upper layer tx */
+static unsigned int tx_stop = 5;
+
 struct ntb_netdev {
        struct list_head list;
        struct pci_dev *pdev;
        struct net_device *ndev;
        struct ntb_transport_qp *qp;
+       struct timer_list tx_timer;
 };
 
 #define        NTB_TX_TIMEOUT_MS       1000
@@ -136,11 +146,42 @@ enqueue_again:
        }
 }
 
+static int __ntb_netdev_maybe_stop_tx(struct net_device *netdev,
+                                     struct ntb_transport_qp *qp, int size)
+{
+       struct ntb_netdev *dev = netdev_priv(netdev);
+
+       netif_stop_queue(netdev);
+       /* Make sure to see the latest value of ntb_transport_tx_free_entry()
+        * since the queue was last started.
+        */
+       smp_mb();
+
+       if (likely(ntb_transport_tx_free_entry(qp) < size)) {
+               mod_timer(&dev->tx_timer, jiffies + usecs_to_jiffies(tx_time));
+               return -EBUSY;
+       }
+
+       netif_start_queue(netdev);
+       return 0;
+}
+
+static int ntb_netdev_maybe_stop_tx(struct net_device *ndev,
+                                   struct ntb_transport_qp *qp, int size)
+{
+       if (netif_queue_stopped(ndev) ||
+           (ntb_transport_tx_free_entry(qp) >= size))
+               return 0;
+
+       return __ntb_netdev_maybe_stop_tx(ndev, qp, size);
+}
+
 static void ntb_netdev_tx_handler(struct ntb_transport_qp *qp, void *qp_data,
                                  void *data, int len)
 {
        struct net_device *ndev = qp_data;
        struct sk_buff *skb;
+       struct ntb_netdev *dev = netdev_priv(ndev);
 
        skb = data;
        if (!skb || !ndev)
@@ -155,6 +196,15 @@ static void ntb_netdev_tx_handler(struct ntb_transport_qp *qp, void *qp_data,
        }
 
        dev_kfree_skb(skb);
+
+       if (ntb_transport_tx_free_entry(dev->qp) >= tx_start) {
+               /* Make sure anybody stopping the queue after this sees the new
+                * value of ntb_transport_tx_free_entry()
+                */
+               smp_mb();
+               if (netif_queue_stopped(ndev))
+                       netif_wake_queue(ndev);
+       }
 }
 
 static netdev_tx_t ntb_netdev_start_xmit(struct sk_buff *skb,
@@ -163,10 +213,15 @@ static netdev_tx_t ntb_netdev_start_xmit(struct sk_buff *skb,
        struct ntb_netdev *dev = netdev_priv(ndev);
        int rc;
 
+       ntb_netdev_maybe_stop_tx(ndev, dev->qp, tx_stop);
+
        rc = ntb_transport_tx_enqueue(dev->qp, skb, skb->data, skb->len);
        if (rc)
                goto err;
 
+       /* check for next submit */
+       ntb_netdev_maybe_stop_tx(ndev, dev->qp, tx_stop);
+
        return NETDEV_TX_OK;
 
 err:
@@ -175,6 +230,23 @@ err:
        return NETDEV_TX_BUSY;
 }
 
+static void ntb_netdev_tx_timer(unsigned long data)
+{
+       struct net_device *ndev = (struct net_device *)data;
+       struct ntb_netdev *dev = netdev_priv(ndev);
+
+       if (ntb_transport_tx_free_entry(dev->qp) < tx_stop) {
+               mod_timer(&dev->tx_timer, jiffies + msecs_to_jiffies(tx_time));
+       } else {
+               /* Make sure anybody stopping the queue after this sees the new
+                * value of ntb_transport_tx_free_entry()
+                */
+               smp_mb();
+               if (netif_queue_stopped(ndev))
+                       netif_wake_queue(ndev);
+       }
+}
+
 static int ntb_netdev_open(struct net_device *ndev)
 {
        struct ntb_netdev *dev = netdev_priv(ndev);
@@ -197,8 +269,11 @@ static int ntb_netdev_open(struct net_device *ndev)
                }
        }
 
+       setup_timer(&dev->tx_timer, ntb_netdev_tx_timer, (unsigned long)ndev);
+
        netif_carrier_off(ndev);
        ntb_transport_link_up(dev->qp);
+       netif_start_queue(ndev);
 
        return 0;
 
@@ -219,6 +294,8 @@ static int ntb_netdev_close(struct net_device *ndev)
        while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
                dev_kfree_skb(skb);
 
+       del_timer_sync(&dev->tx_timer);
+
        return 0;
 }