[ewg] [PATCH] IB/ipoib: reduce CM tx object size

[Eli Cohen]

>From 74218f2b8fff790a0fa35c2bf3aa6ab48c08ba81 Mon Sep 17 00:00:00 2001
From: Eli Cohen <eli at mellanox.co.il>
Date: Sun, 25 May 2008 18:58:13 +0300
Subject: [PATCH] IB/ipoib: reduce CM tx object size

Since IPOIB CM does not publish NETIF_F_SG, we don't need a mapping
array so define a new struct with one u64 field and use it.

Signed-off-by: Eli Cohen <eli at mellanox.co.il>
---
 drivers/infiniband/ulp/ipoib/ipoib.h    |    7 ++++++-
 drivers/infiniband/ulp/ipoib/ipoib_cm.c |   12 ++++++------
 2 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/infiniband/ulp/ipoib/ipoib.h b/drivers/infiniband/ulp/ipoib/ipoib.h
index e39bf36..2b6f60b 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib.h
+++ b/drivers/infiniband/ulp/ipoib/ipoib.h
@@ -109,6 +109,11 @@ enum {
 
 /* structs */
 
+struct ipoib_cm_tx_buf {
+	struct sk_buff *skb;
+	u64		mapping;
+};
+
 struct ipoib_header {
 	__be16	proto;
 	u16	reserved;
@@ -208,7 +213,7 @@ struct ipoib_cm_tx {
 	struct net_device   *dev;
 	struct ipoib_neigh  *neigh;
 	struct ipoib_path   *path;
-	struct ipoib_tx_buf *tx_ring;
+	struct ipoib_cm_tx_buf *tx_ring;
 	unsigned	     tx_head;
 	unsigned	     tx_tail;
 	unsigned long	     flags;
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_cm.c b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
index 9e0facc..064971d 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_cm.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
@@ -662,7 +662,7 @@ static inline int post_send(struct ipoib_dev_priv *priv,
 void ipoib_cm_send(struct net_device *dev, struct sk_buff *skb, struct ipoib_cm_tx *tx)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
-	struct ipoib_tx_buf *tx_req;
+	struct ipoib_cm_tx_buf *tx_req;
 	u64 addr;
 
 	if (unlikely(skb->len > tx->mtu)) {
@@ -693,7 +693,7 @@ void ipoib_cm_send(struct net_device *dev, struct sk_buff *skb, struct ipoib_cm_
 		return;
 	}
 
-	tx_req->mapping[0] = addr;
+	tx_req->mapping = addr;
 
 	if (unlikely(post_send(priv, tx, tx->tx_head & (ipoib_sendq_size - 1),
 			       addr, skb->len))) {
@@ -718,7 +718,7 @@ void ipoib_cm_handle_tx_wc(struct net_device *dev, struct ib_wc *wc)
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	struct ipoib_cm_tx *tx = wc->qp->qp_context;
 	unsigned int wr_id = wc->wr_id & ~IPOIB_OP_CM;
-	struct ipoib_tx_buf *tx_req;
+	struct ipoib_cm_tx_buf *tx_req;
 	unsigned long flags;
 
 	ipoib_dbg_data(priv, "cm send completion: id %d, status: %d\n",
@@ -732,7 +732,7 @@ void ipoib_cm_handle_tx_wc(struct net_device *dev, struct ib_wc *wc)
 
 	tx_req = &tx->tx_ring[wr_id];
 
-	ib_dma_unmap_single(priv->ca, tx_req->mapping[0], tx_req->skb->len, DMA_TO_DEVICE);
+	ib_dma_unmap_single(priv->ca, tx_req->mapping, tx_req->skb->len, DMA_TO_DEVICE);
 
 	/* FIXME: is this right? Shouldn't we only increment on success? */
 	++dev->stats.tx_packets;
@@ -1102,7 +1102,7 @@ err_tx:
 static void ipoib_cm_tx_destroy(struct ipoib_cm_tx *p)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(p->dev);
-	struct ipoib_tx_buf *tx_req;
+	struct ipoib_cm_tx_buf *tx_req;
 	unsigned long flags;
 	unsigned long begin;
 
@@ -1130,7 +1130,7 @@ timeout:
 
 	while ((int) p->tx_tail - (int) p->tx_head < 0) {
 		tx_req = &p->tx_ring[p->tx_tail & (ipoib_sendq_size - 1)];
-		ib_dma_unmap_single(priv->ca, tx_req->mapping[0], tx_req->skb->len,
+		ib_dma_unmap_single(priv->ca, tx_req->mapping, tx_req->skb->len,
 				    DMA_TO_DEVICE);
 		dev_kfree_skb_any(tx_req->skb);
 		++p->tx_tail;
-- 
1.5.5.1