[PATCH] skge: compute available ring buffers

Don't need to keep track of available buffers, it is simpler
to just compute the value (ala e1000). Don't need tes on link up
because should always have available buffers then.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

diff --git a/drivers/net/skge.c b/drivers/net/skge.c
index a261766bc0528e0a4be3a990f3eb4270d382b90a..a6f42fc857384aa6a68583bfd3ee36898ab8ead0 100644 (file)
--- a/drivers/net/skge.c
+++ b/drivers/net/skge.c
@@ -847,8 +847,7 @@ static void skge_link_up(struct skge_port *skge)
                    LED_BLK_OFF|LED_SYNC_OFF|LED_ON);
 
        netif_carrier_on(skge->netdev);
-       if (skge->tx_avail > MAX_SKB_FRAGS + 1)
-               netif_wake_queue(skge->netdev);
+       netif_wake_queue(skge->netdev);
 
        if (netif_msg_link(skge))
                printk(KERN_INFO PFX
@@ -2190,8 +2189,6 @@ static int skge_up(struct net_device *dev)
        if (err)
                goto free_rx_ring;
 
-       skge->tx_avail = skge->tx_ring.count - 1;
-
        /* Initialize MAC */
        spin_lock_bh(&hw->phy_lock);
        if (hw->chip_id == CHIP_ID_GENESIS)
@@ -2294,6 +2291,12 @@ static int skge_down(struct net_device *dev)
        return 0;
 }
 
+static inline int skge_avail(const struct skge_ring *ring)
+{
+       return ((ring->to_clean > ring->to_use) ? 0 : ring->count)
+               + (ring->to_clean - ring->to_use) - 1;
+}
+
 static int skge_xmit_frame(struct sk_buff *skb, struct net_device *dev)
 {
        struct skge_port *skge = netdev_priv(dev);
@@ -2314,7 +2317,7 @@ static int skge_xmit_frame(struct sk_buff *skb, struct net_device *dev)
                return NETDEV_TX_LOCKED;
        }
 
-       if (unlikely(skge->tx_avail < skb_shinfo(skb)->nr_frags +1)) {
+       if (unlikely(skge_avail(&skge->tx_ring) < skb_shinfo(skb)->nr_frags + 1)) {
                if (!netif_queue_stopped(dev)) {
                        netif_stop_queue(dev);
 
@@ -2390,8 +2393,7 @@ static int skge_xmit_frame(struct sk_buff *skb, struct net_device *dev)
                       dev->name, e - ring->start, skb->len);
 
        ring->to_use = e->next;
-       skge->tx_avail -= skb_shinfo(skb)->nr_frags + 1;
-       if (skge->tx_avail <= MAX_SKB_FRAGS + 1) {
+       if (skge_avail(&skge->tx_ring) <= MAX_SKB_FRAGS + 1) {
                pr_debug("%s: transmit queue full\n", dev->name);
                netif_stop_queue(dev);
        }
@@ -2416,14 +2418,12 @@ static void skge_tx_complete(struct skge_port *skge, struct skge_element *last)
                e->skb = NULL;
                pci_unmap_single(pdev, pci_unmap_addr(e, mapaddr),
                                 skb_headlen(skb), PCI_DMA_TODEVICE);
-               ++skge->tx_avail;
 
                for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
                        e = e->next;
                        pci_unmap_page(pdev, pci_unmap_addr(e, mapaddr),
                                       skb_shinfo(skb)->frags[i].size,
                                       PCI_DMA_TODEVICE);
-                       ++skge->tx_avail;
                }
 
                dev_kfree_skb(skb);
@@ -2688,7 +2688,7 @@ static void skge_tx_done(struct skge_port *skge)
 
        skge_write8(skge->hw, Q_ADDR(txqaddr[skge->port], Q_CSR), CSR_IRQ_CL_F);
 
-       if (skge->tx_avail > MAX_SKB_FRAGS + 1)
+       if (skge_avail(&skge->tx_ring) > MAX_SKB_FRAGS + 1)
                netif_wake_queue(skge->netdev);
 
        spin_unlock(&skge->tx_lock);

diff --git a/drivers/net/skge.h b/drivers/net/skge.h
index 2efdacc290e58962cb8917953e78cb7afd6ca17d..1f1ce88c81863ed10a7964a94936980efed56b95 100644 (file)
--- a/drivers/net/skge.h
+++ b/drivers/net/skge.h
@@ -2418,7 +2418,6 @@ struct skge_port {
        int                  port;
 
        spinlock_t           tx_lock;
-       u32                  tx_avail;
        struct skge_ring     tx_ring;
        struct skge_ring     rx_ring;