[patch 016/108] e1000e: stop unnecessary polling when using msi-x

[Greg KH]

2.6.30-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Andy Gospodarek <andy@xxxxxxxxxxxxx>

[ Upstream commit 679e8a0f0ae3333e94b1d374d07775fce9066025 ]

The last hunk of this commit:

    commit 12d04a3c12b420f23398b4d650127642469a60a6
    Author: Alexander Duyck <alexander.h.duyck@xxxxxxxxx>
    Date:   Wed Mar 25 22:05:03 2009 +0000

        e1000e: commonize tx cleanup routine to match e1000 & igb

changed the logic for determining if we should call napi_complete or
not at then end of a napi poll.

If the NIC is using MSI-X with no work to do in ->poll, net_rx_action
can just spin indefinitely on older kernels and for 2 jiffies on newer
kernels since napi_complete is never called and budget isn't
decremented.

Discovered and verified while testing driver backport to an older
kernel.

Signed-off-by: Andy Gospodarek <andy@xxxxxxxxxxxxx>
Acked-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
 drivers/net/e1000e/netdev.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/e1000e/netdev.c
+++ b/drivers/net/e1000e/netdev.c
@@ -1996,7 +1996,7 @@ static int e1000_clean(struct napi_struc
 	struct e1000_adapter *adapter = container_of(napi, struct e1000_adapter, napi);
 	struct e1000_hw *hw = &adapter->hw;
 	struct net_device *poll_dev = adapter->netdev;
-	int tx_cleaned = 0, work_done = 0;
+	int tx_cleaned = 1, work_done = 0;
 
 	adapter = netdev_priv(poll_dev);
 


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