[PATCH] drivers/net/amd8111e.c: fix NAPI interrupt in poll

  This patch makes the netif_rx_complete() and rx_interrupt_enable
  atomic when exiting the poll() method, so to avoid interrupt in poll.
  It also fixes the rx interrupt check logic in interrupt handler.

  Signed-off-by: Liu Tao <liutao1980@gmail.com>
  Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

diff --git a/drivers/net/amd8111e.c b/drivers/net/amd8111e.c
index f2e937abf7b4d8c639675100dd5ffc74c5323ebe..b7dd7260cafbf137656a3f50059a7136b55ec661 100755 (executable)
--- a/drivers/net/amd8111e.c
+++ b/drivers/net/amd8111e.c
@@ -738,6 +738,7 @@ static int amd8111e_rx_poll(struct net_device *dev, int * budget)
        short vtag;
 #endif
        int rx_pkt_limit = dev->quota;
+       unsigned long flags;
        
        do{   
                /* process receive packets until we use the quota*/
@@ -841,18 +842,19 @@ static int amd8111e_rx_poll(struct net_device *dev, int * budget)
        /* Receive descriptor is empty now */
        dev->quota -= num_rx_pkt;
        *budget -= num_rx_pkt;
+
+       spin_lock_irqsave(&lp->lock, flags);
        netif_rx_complete(dev);
-       /* enable receive interrupt */
        writel(VAL0|RINTEN0, mmio + INTEN0);
        writel(VAL2 | RDMD0, mmio + CMD0);
+       spin_unlock_irqrestore(&lp->lock, flags);
        return 0;
+
 rx_not_empty:
        /* Do not call a netif_rx_complete */
        dev->quota -= num_rx_pkt;       
        *budget -= num_rx_pkt;
        return 1;
-
-       
 }
 
 #else
@@ -1261,18 +1263,20 @@ static irqreturn_t amd8111e_interrupt(int irq, void *dev_id, struct pt_regs *reg
        struct net_device * dev = (struct net_device *) dev_id;
        struct amd8111e_priv *lp = netdev_priv(dev);
        void __iomem *mmio = lp->mmio;
-       unsigned int intr0;
+       unsigned int intr0, intren0;
        unsigned int handled = 1;
 
-       if(dev == NULL)
+       if(unlikely(dev == NULL))
                return IRQ_NONE;
 
-       if (regs) spin_lock (&lp->lock);
+       spin_lock(&lp->lock);
+
        /* disabling interrupt */
        writel(INTREN, mmio + CMD0);
 
        /* Read interrupt status */
        intr0 = readl(mmio + INT0);
+       intren0 = readl(mmio + INTEN0);
 
        /* Process all the INT event until INTR bit is clear. */
 
@@ -1293,11 +1297,11 @@ static irqreturn_t amd8111e_interrupt(int irq, void *dev_id, struct pt_regs *reg
                        /* Schedule a polling routine */
                        __netif_rx_schedule(dev);
                }
-               else {
+               else if (intren0 & RINTEN0) {
                        printk("************Driver bug! \
                                interrupt while in poll\n");
-                       /* Fix by disabling interrupts */
-                       writel(RINT0, mmio + INT0);
+                       /* Fix by disable receive interrupts */
+                       writel(RINTEN0, mmio + INTEN0);
                }
        }
 #else
@@ -1321,7 +1325,7 @@ static irqreturn_t amd8111e_interrupt(int irq, void *dev_id, struct pt_regs *reg
 err_no_interrupt:
        writel( VAL0 | INTREN,mmio + CMD0);
        
-       if (regs) spin_unlock(&lp->lock);
+       spin_unlock(&lp->lock);
        
        return IRQ_RETVAL(handled);
 }