USBNET: increase max rx/tx qlen for improving USB3 thoughtput

The default RX_QLEN()/TX_QLEN() didn't consider super speed
USB device, so only max 4 URBs are scheduled at the same time
for tx/rx, then USB3 NIC can't perform very well.

With this patch, both rx and tx thoughput are increased more than
100Mbps when doing iperf test on ax88179_178a USB 3.0 NIC.

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ming Lei 2013-07-25 13:47:54 +08:00 committed by David S. Miller
parent a88c32ae15
commit 452c447a49

View File

@ -355,6 +355,15 @@ void usbnet_update_max_qlen(struct usbnet *dev)
dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size; dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size;
dev->tx_qlen = MAX_QUEUE_MEMORY / dev->hard_mtu; dev->tx_qlen = MAX_QUEUE_MEMORY / dev->hard_mtu;
break; break;
case USB_SPEED_SUPER:
/*
* Not take default 5ms qlen for super speed HC to
* save memory, and iperf tests show 2.5ms qlen can
* work well
*/
dev->rx_qlen = 5 * MAX_QUEUE_MEMORY / dev->rx_urb_size;
dev->tx_qlen = 5 * MAX_QUEUE_MEMORY / dev->hard_mtu;
break;
default: default:
dev->rx_qlen = dev->tx_qlen = 4; dev->rx_qlen = dev->tx_qlen = 4;
} }