[patch 5/7] 2.6.5-bk-netdev - r8169 queue

[Francois Romieu <romieu@xxxxxxxxxxxxx>]

If a few packets have been scheduled for Tx, it is possible to keep looping
in the Tx irq handler as soon as the irq for the first packet has been
received until the descriptor of the last packet has been sent (with 
interrupts disabled btw).


 drivers/net/r8169.c |   28 +++++++++++++++-------------
 1 files changed, 15 insertions(+), 13 deletions(-)

diff -puN drivers/net/r8169.c~r8169-kill-potential-busy-loop drivers/net/r8169.c
--- linux-2.6.5/drivers/net/r8169.c~r8169-kill-potential-busy-loop      
2004-04-05 23:06:15.000000000 +0200
+++ linux-2.6.5-fr/drivers/net/r8169.c  2004-04-05 23:06:15.000000000 +0200
@@ -1366,22 +1366,24 @@ rtl8169_tx_interrupt(struct net_device *
 
        while (tx_left > 0) {
                int entry = dirty_tx % NUM_TX_DESC;
+               struct sk_buff *skb = tp->Tx_skbuff[entry];
+               u32 status;
 
                rmb();
-               if (!(le32_to_cpu(tp->TxDescArray[entry].status) & OWNbit)) {
-                       struct sk_buff *skb = tp->Tx_skbuff[entry];
+               status = le32_to_cpu(tp->TxDescArray[entry].status);
+               if (status & OWNbit)
+                       break;
 
-                       /* FIXME: is it really accurate for TxErr ? */
-                       tp->stats.tx_bytes += skb->len >= ETH_ZLEN ?
-                                             skb->len : ETH_ZLEN;
-                       tp->stats.tx_packets++;
-                       rtl8169_unmap_tx_skb(tp->pci_dev, tp->Tx_skbuff + entry,
-                                            tp->TxDescArray + entry);
-                       dev_kfree_skb_irq(skb);
-                       tp->Tx_skbuff[entry] = NULL;
-                       dirty_tx++;
-                       tx_left--;
-               }
+               /* FIXME: is it really accurate for TxErr ? */
+               tp->stats.tx_bytes += skb->len >= ETH_ZLEN ?
+                                     skb->len : ETH_ZLEN;
+               tp->stats.tx_packets++;
+               rtl8169_unmap_tx_skb(tp->pci_dev, tp->Tx_skbuff + entry,
+                                    tp->TxDescArray + entry);
+               dev_kfree_skb_irq(skb);
+               tp->Tx_skbuff[entry] = NULL;
+               dirty_tx++;
+               tx_left--;
        }
 
        if (tp->dirty_tx != dirty_tx) {

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