From: Stephen Hemminger <shemminger@osdl.org>
Date: Wed, 17 May 2006 21:37:06 +0000 (-0700)
Subject: [PATCH] sky2: force NAPI repoll if busy
X-Git-Tag: v2.6.17-rc5~84
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=86fba6342dee30a1533b14da284d79e4eb66de26;p=linux-2.6

[PATCH] sky2: force NAPI repoll if busy

If the status ring processing can't keep up with the incoming frames,
it is more efficient to have NAPI keep scheduling the poll routine
rather than causing another interrupt.

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

diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c
index bb185e5efa..9729062d1f 100644
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -1919,6 +1919,12 @@ static inline void sky2_tx_done(struct net_device *dev, u16 last)
 	}
 }
 
+/* Is status ring empty or is there more to do? */
+static inline int sky2_more_work(const struct sky2_hw *hw)
+{
+	return (hw->st_idx != sky2_read16(hw, STAT_PUT_IDX));
+}
+
 /* Process status response ring */
 static int sky2_status_intr(struct sky2_hw *hw, int to_do)
 {
@@ -2191,19 +2197,19 @@ static int sky2_poll(struct net_device *dev0, int *budget)
 	if (status & Y2_IS_CHK_TXA2)
 		sky2_descriptor_error(hw, 1, "transmit", Y2_IS_CHK_TXA2);
 
-	if (status & Y2_IS_STAT_BMU)
-		sky2_write32(hw, STAT_CTRL, SC_STAT_CLR_IRQ);
-
 	work_done = sky2_status_intr(hw, work_limit);
 	*budget -= work_done;
 	dev0->quota -= work_done;
 
-	if (work_done >= work_limit)
+	if (status & Y2_IS_STAT_BMU)
+		sky2_write32(hw, STAT_CTRL, SC_STAT_CLR_IRQ);
+
+	if (sky2_more_work(hw))
 		return 1;
 
 	netif_rx_complete(dev0);
 
-	status = sky2_read32(hw, B0_Y2_SP_LISR);
+	sky2_read32(hw, B0_Y2_SP_LISR);
 	return 0;
 }