From: Stephen Hemminger <shemminger@osdl.org>
Date: Mon, 8 May 2006 22:11:26 +0000 (-0700)
Subject: sky2: backout NAPI reschedule
X-Git-Tag: v2.6.17-rc4~10^2~13
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d324031245abbb54e4e0321004430826052b6c37;p=linux-2.6

sky2: backout NAPI reschedule

This is a backout of earlier patch.

The whole rescheduling hack was a bad idea. It doesn't really solve
the problem and it makes the code more complicated for no good reason.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
---

diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c
index 227df9876a..76da74fbe8 100644
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -2105,7 +2105,6 @@ static int sky2_poll(struct net_device *dev0, int *budget)
 	int work_done = 0;
 	u32 status = sky2_read32(hw, B0_Y2_SP_EISR);
 
- restart_poll:
 	if (unlikely(status & ~Y2_IS_STAT_BMU)) {
 		if (status & Y2_IS_HW_ERR)
 			sky2_hw_intr(hw);
@@ -2136,7 +2135,7 @@ static int sky2_poll(struct net_device *dev0, int *budget)
 	}
 
 	if (status & Y2_IS_STAT_BMU) {
-		work_done += sky2_status_intr(hw, work_limit - work_done);
+		work_done = sky2_status_intr(hw, work_limit);
 		*budget -= work_done;
 		dev0->quota -= work_done;
 
@@ -2148,22 +2147,9 @@ static int sky2_poll(struct net_device *dev0, int *budget)
 
 	mod_timer(&hw->idle_timer, jiffies + HZ);
 
-	local_irq_disable();
-	__netif_rx_complete(dev0);
+	netif_rx_complete(dev0);
 
 	status = sky2_read32(hw, B0_Y2_SP_LISR);
-
-	if (unlikely(status)) {
-		/* More work pending, try and keep going */
-		if (__netif_rx_schedule_prep(dev0)) {
-			__netif_rx_reschedule(dev0, work_done);
-			status = sky2_read32(hw, B0_Y2_SP_EISR);
-			local_irq_enable();
-			goto restart_poll;
-		}
-	}
-
-	local_irq_enable();
 	return 0;
 }
 
@@ -2181,6 +2167,8 @@ static irqreturn_t sky2_intr(int irq, void *dev_id, struct pt_regs *regs)
 	prefetch(&hw->st_le[hw->st_idx]);
 	if (likely(__netif_rx_schedule_prep(dev0)))
 		__netif_rx_schedule(dev0);
+	else
+		printk(KERN_DEBUG PFX "irq race detected\n");
 
 	return IRQ_HANDLED;
 }
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 309f9190a9..a461b51d60 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -831,21 +831,19 @@ static inline void netif_rx_schedule(struct net_device *dev)
 		__netif_rx_schedule(dev);
 }
 
-
-static inline void  __netif_rx_reschedule(struct net_device *dev, int undo)
-{
-	dev->quota += undo;
-	list_add_tail(&dev->poll_list, &__get_cpu_var(softnet_data).poll_list);
-	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
-}
-
-/* Try to reschedule poll. Called by dev->poll() after netif_rx_complete(). */
+/* Try to reschedule poll. Called by dev->poll() after netif_rx_complete().
+ * Do not inline this?
+ */
 static inline int netif_rx_reschedule(struct net_device *dev, int undo)
 {
 	if (netif_rx_schedule_prep(dev)) {
 		unsigned long flags;
+
+		dev->quota += undo;
+
 		local_irq_save(flags);
-		__netif_rx_reschedule(dev, undo);
+		list_add_tail(&dev->poll_list, &__get_cpu_var(softnet_data).poll_list);
+		__raise_softirq_irqoff(NET_RX_SOFTIRQ);
 		local_irq_restore(flags);
 		return 1;
 	}