IPoIB: Consolidate private neighbour data handling

Consolidate IPoIB's private neighbour data handling into
ipoib_neigh_alloc() and ipoib_neigh_free().  This will make it easier
to keep track of the neighbour structures that IPoIB is handling, and
is a nice cleanup of the code:

add/remove: 2/1 grow/shrink: 1/8 up/down: 100/-178 (-78)
function                                     old     new   delta
ipoib_neigh_alloc                              -      61     +61
ipoib_neigh_free                               -      36     +36
ipoib_mcast_join_finish                     1288    1291      +3
path_rec_completion                          575     573      -2
ipoib_mcast_join_task                        664     660      -4
ipoib_neigh_destructor                       101      92      -9
ipoib_neigh_setup_dev                         14       3     -11
ipoib_neigh_setup                             17       -     -17
path_free                                    238     215     -23
ipoib_mcast_free                             329     306     -23
ipoib_mcast_send                             718     684     -34
neigh_add_path                               705     650     -55

Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

3 files changed, 34 insertions, 17 deletions

diff --git a/drivers/infiniband/ulp/ipoib/ipoib.h b/drivers/infiniband/ulp/ipoib/ipoib.h
index b640107fb732..374109df7303 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib.h
+++ b/drivers/infiniband/ulp/ipoib/ipoib.h
@@ -230,6 +230,9 @@ static inline struct ipoib_neigh **to_ipoib_neigh(struct neighbour *neigh)
                                      INFINIBAND_ALEN, sizeof(void *));
 }
 
+struct ipoib_neigh *ipoib_neigh_alloc(struct neighbour *neigh);
+void ipoib_neigh_free(struct ipoib_neigh *neigh);
+
 extern struct workqueue_struct *ipoib_workqueue;
 
 /* functions */
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index 9b0bd7c746ca..8f6607bf4261 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -252,8 +252,8 @@ static void path_free(struct net_device *dev, struct ipoib_path *path)
                  */
                 if (neigh->ah)
                         ipoib_put_ah(neigh->ah);
-                *to_ipoib_neigh(neigh->neighbour) = NULL;
-                kfree(neigh);
+
+                ipoib_neigh_free(neigh);
         }
 
         spin_unlock_irqrestore(&priv->lock, flags);
@@ -481,7 +481,7 @@ static void neigh_add_path(struct sk_buff *skb, struct net_device *dev)
         struct ipoib_path *path;
         struct ipoib_neigh *neigh;
 
-        neigh = kmalloc(sizeof *neigh, GFP_ATOMIC);
+        neigh = ipoib_neigh_alloc(skb->dst->neighbour);
         if (!neigh) {
                 ++priv->stats.tx_dropped;
                 dev_kfree_skb_any(skb);
@@ -489,8 +489,6 @@ static void neigh_add_path(struct sk_buff *skb, struct net_device *dev)
         }
 
         skb_queue_head_init(&neigh->queue);
-        neigh->neighbour = skb->dst->neighbour;
-        *to_ipoib_neigh(skb->dst->neighbour) = neigh;
 
         /*
          * We can only be called from ipoib_start_xmit, so we're
@@ -503,7 +501,7 @@ static void neigh_add_path(struct sk_buff *skb, struct net_device *dev)
                 path = path_rec_create(dev,
                                        (union ib_gid *) (skb->dst->neighbour->ha + 4));
                 if (!path)
-                        goto err;
+                        goto err_path;
 
                 __path_add(dev, path);
         }
@@ -521,17 +519,17 @@ static void neigh_add_path(struct sk_buff *skb, struct net_device *dev)
                 __skb_queue_tail(&neigh->queue, skb);
 
                 if (!path->query && path_rec_start(dev, path))
-                        goto err;
+                        goto err_list;
         }
 
         spin_unlock(&priv->lock);
         return;
 
-err:
-        *to_ipoib_neigh(skb->dst->neighbour) = NULL;
+err_list:
         list_del(&neigh->list);
-        kfree(neigh);
 
+err_path:
+        ipoib_neigh_free(neigh);
         ++priv->stats.tx_dropped;
         dev_kfree_skb_any(skb);
 
@@ -763,8 +761,7 @@ static void ipoib_neigh_destructor(struct neighbour *n)
                 if (neigh->ah)
                         ah = neigh->ah;
                 list_del(&neigh->list);
-                *to_ipoib_neigh(n) = NULL;
-                kfree(neigh);
+                ipoib_neigh_free(neigh);
         }
 
         spin_unlock_irqrestore(&priv->lock, flags);
@@ -773,6 +770,26 @@ static void ipoib_neigh_destructor(struct neighbour *n)
                 ipoib_put_ah(ah);
 }
 
+struct ipoib_neigh *ipoib_neigh_alloc(struct neighbour *neighbour)
+{
+        struct ipoib_neigh *neigh;
+
+        neigh = kmalloc(sizeof *neigh, GFP_ATOMIC);
+        if (!neigh)
+                return NULL;
+
+        neigh->neighbour = neighbour;
+        *to_ipoib_neigh(neighbour) = neigh;
+
+        return neigh;
+}
+
+void ipoib_neigh_free(struct ipoib_neigh *neigh)
+{
+        *to_ipoib_neigh(neigh->neighbour) = NULL;
+        kfree(neigh);
+}
+
 static int ipoib_neigh_setup_dev(struct net_device *dev, struct neigh_parms *parms)
 {
         parms->neigh_destructor = ipoib_neigh_destructor;
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
index 93c462eaf4fd..a8395ef06c17 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
@@ -114,8 +114,7 @@ static void ipoib_mcast_free(struct ipoib_mcast *mcast)
                  */
                 if (neigh->ah)
                         ipoib_put_ah(neigh->ah);
-                *to_ipoib_neigh(neigh->neighbour) = NULL;
-                kfree(neigh);
+                ipoib_neigh_free(neigh);
         }
 
         spin_unlock_irqrestore(&priv->lock, flags);
@@ -772,13 +771,11 @@ out:
                 if (skb->dst            &&
                     skb->dst->neighbour &&
                     !*to_ipoib_neigh(skb->dst->neighbour)) {
-                        struct ipoib_neigh *neigh = kmalloc(sizeof *neigh, GFP_ATOMIC);
+                        struct ipoib_neigh *neigh = ipoib_neigh_alloc(skb->dst->neighbour);
 
                         if (neigh) {
                                 kref_get(&mcast->ah->ref);
                                 neigh->ah       = mcast->ah;
-                                neigh->neighbour = skb->dst->neighbour;
-                                *to_ipoib_neigh(skb->dst->neighbour) = neigh;
                                 list_add_tail(&neigh->list, &mcast->neigh_list);
                         }
                 }