IPoIB: Convert to NAPI

Convert the IP-over-InfiniBand network device driver over to using
NAPI to handle completions for the main CQ.  This covers all receives
as well as datagram mode sends; send completions for connected mode
connections are still handled from interrupt context.

Signed-off-by: Roland Dreier <rolandd@cisco.com>

4 files changed, 74 insertions, 20 deletions

diff --git a/drivers/infiniband/ulp/ipoib/ipoib.h b/drivers/infiniband/ulp/ipoib/ipoib.h
index fd558267d1cb..15867af33c44 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib.h
+++ b/drivers/infiniband/ulp/ipoib/ipoib.h
@@ -311,6 +311,7 @@ extern struct workqueue_struct *ipoib_workqueue;
 
 /* functions */
 
+int ipoib_poll(struct net_device *dev, int *budget);
 void ipoib_ib_completion(struct ib_cq *cq, void *dev_ptr);
 
 struct ipoib_ah *ipoib_create_ah(struct net_device *dev,
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_cm.c b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
index b8089a041581..785bc8505f2a 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_cm.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
@@ -416,7 +416,7 @@ void ipoib_cm_handle_rx_wc(struct net_device *dev, struct ib_wc *wc)
         skb->dev = dev;
         /* XXX get correct PACKET_ type here */
         skb->pkt_type = PACKET_HOST;
-        netif_rx_ni(skb);
+        netif_receive_skb(skb);
 
 repost:
         if (unlikely(ipoib_cm_post_receive(dev, wr_id)))
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_ib.c b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
index 1bdb9101911a..68d72c6f7ffb 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_ib.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
@@ -226,7 +226,7 @@ static void ipoib_ib_handle_rx_wc(struct net_device *dev, struct ib_wc *wc)
                 skb->dev = dev;
                 /* XXX get correct PACKET_ type here */
                 skb->pkt_type = PACKET_HOST;
-                netif_rx_ni(skb);
+                netif_receive_skb(skb);
         } else {
                 ipoib_dbg_data(priv, "dropping loopback packet\n");
                 dev_kfree_skb_any(skb);
@@ -280,28 +280,63 @@ static void ipoib_ib_handle_tx_wc(struct net_device *dev, struct ib_wc *wc)
                            wc->status, wr_id, wc->vendor_err);
 }
 
-static void ipoib_ib_handle_wc(struct net_device *dev, struct ib_wc *wc)
+int ipoib_poll(struct net_device *dev, int *budget)
 {
-        if (wc->wr_id & IPOIB_CM_OP_SRQ)
-                ipoib_cm_handle_rx_wc(dev, wc);
-        else if (wc->wr_id & IPOIB_OP_RECV)
-                ipoib_ib_handle_rx_wc(dev, wc);
-        else
-                ipoib_ib_handle_tx_wc(dev, wc);
+        struct ipoib_dev_priv *priv = netdev_priv(dev);
+        int max = min(*budget, dev->quota);
+        int done;
+        int t;
+        int empty;
+        int n, i;
+
+        done  = 0;
+        empty = 0;
+
+        while (max) {
+                t = min(IPOIB_NUM_WC, max);
+                n = ib_poll_cq(priv->cq, t, priv->ibwc);
+
+                for (i = 0; i < n; ++i) {
+                        struct ib_wc *wc = priv->ibwc + i;
+
+                        if (wc->wr_id & IPOIB_CM_OP_SRQ) {
+                                ++done;
+                                --max;
+                                ipoib_cm_handle_rx_wc(dev, wc);
+                        } else if (wc->wr_id & IPOIB_OP_RECV) {
+                                ++done;
+                                --max;
+                                ipoib_ib_handle_rx_wc(dev, wc);
+                        } else
+                                ipoib_ib_handle_tx_wc(dev, wc);
+                }
+
+                if (n != t) {
+                        empty = 1;
+                        break;
+                }
+        }
+
+        dev->quota -= done;
+        *budget    -= done;
+
+        if (empty) {
+                netif_rx_complete(dev);
+                if (unlikely(ib_req_notify_cq(priv->cq,
+                                              IB_CQ_NEXT_COMP |
+                                              IB_CQ_REPORT_MISSED_EVENTS)) &&
+                    netif_rx_reschedule(dev, 0))
+                        return 1;
+
+                return 0;
+        }
+
+        return 1;
 }
 
 void ipoib_ib_completion(struct ib_cq *cq, void *dev_ptr)
 {
-        struct net_device *dev = (struct net_device *) dev_ptr;
-        struct ipoib_dev_priv *priv = netdev_priv(dev);
-        int n, i;
-
-        ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
-        do {
-                n = ib_poll_cq(cq, IPOIB_NUM_WC, priv->ibwc);
-                for (i = 0; i < n; ++i)
-                        ipoib_ib_handle_wc(dev, priv->ibwc + i);
-        } while (n == IPOIB_NUM_WC);
+        netif_rx_schedule(dev_ptr);
 }
 
 static inline int post_send(struct ipoib_dev_priv *priv,
@@ -514,9 +549,10 @@ int ipoib_ib_dev_stop(struct net_device *dev)
         struct ib_qp_attr qp_attr;
         unsigned long begin;
         struct ipoib_tx_buf *tx_req;
-        int i;
+        int i, n;
 
         clear_bit(IPOIB_FLAG_INITIALIZED, &priv->flags);
+        netif_poll_disable(dev);
 
         ipoib_cm_dev_stop(dev);
 
@@ -568,6 +604,18 @@ int ipoib_ib_dev_stop(struct net_device *dev)
                         goto timeout;
                 }
 
+                do {
+                        n = ib_poll_cq(priv->cq, IPOIB_NUM_WC, priv->ibwc);
+                        for (i = 0; i < n; ++i) {
+                                if (priv->ibwc[i].wr_id & IPOIB_CM_OP_SRQ)
+                                        ipoib_cm_handle_rx_wc(dev, priv->ibwc + i);
+                                else if (priv->ibwc[i].wr_id & IPOIB_OP_RECV)
+                                        ipoib_ib_handle_rx_wc(dev, priv->ibwc + i);
+                                else
+                                        ipoib_ib_handle_tx_wc(dev, priv->ibwc + i);
+                        }
+                } while (n == IPOIB_NUM_WC);
+
                 msleep(1);
         }
 
@@ -596,6 +644,9 @@ timeout:
                 msleep(1);
         }
 
+        netif_poll_enable(dev);
+        ib_req_notify_cq(priv->cq, IB_CQ_NEXT_COMP);
+
         return 0;
 }
 
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index b4c380c5a3ba..0a428f2b05c7 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -948,6 +948,8 @@ static void ipoib_setup(struct net_device *dev)
         dev->hard_header         = ipoib_hard_header;
         dev->set_multicast_list  = ipoib_set_mcast_list;
         dev->neigh_setup         = ipoib_neigh_setup_dev;
+        dev->poll                = ipoib_poll;
+        dev->weight              = 100;
 
         dev->watchdog_timeo      = HZ;