From 7fa6b06689085a3e2237cf810f5e0c114e00a2da Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Wed, 27 Sep 2006 20:33:34 -0700 Subject: [NET] loopback: minor statistics optimization The loopback device status structure is a singleton and doesn't need to be allocated. Add ethtool_ops hooks to show checksum always on, and make ethtool_ops const. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- drivers/net/loopback.c | 31 ++++++++++++++----------------- 1 file changed, 14 insertions(+), 17 deletions(-) (limited to 'drivers/net/loopback.c') diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c index f429b19bf620..4178b4b1d2df 100644 --- a/drivers/net/loopback.c +++ b/drivers/net/loopback.c @@ -161,15 +161,13 @@ static int loopback_xmit(struct sk_buff *skb, struct net_device *dev) return(0); } +static struct net_device_stats loopback_stats; + static struct net_device_stats *get_stats(struct net_device *dev) { - struct net_device_stats *stats = dev->priv; + struct net_device_stats *stats = &loopback_stats; int i; - if (!stats) { - return NULL; - } - memset(stats, 0, sizeof(struct net_device_stats)); for_each_possible_cpu(i) { @@ -185,19 +183,28 @@ static struct net_device_stats *get_stats(struct net_device *dev) return stats; } -static u32 loopback_get_link(struct net_device *dev) +static u32 always_on(struct net_device *dev) { return 1; } static const struct ethtool_ops loopback_ethtool_ops = { - .get_link = loopback_get_link, + .get_link = always_on, .get_tso = ethtool_op_get_tso, .set_tso = ethtool_op_set_tso, + .get_tx_csum = always_on, + .get_sg = always_on, + .get_rx_csum = always_on, }; +/* + * The loopback device is special. There is only one instance and + * it is statically allocated. Don't do this for other devices. + */ struct net_device loopback_dev = { .name = "lo", + .get_stats = &get_stats, + .priv = &loopback_stats, .mtu = (16 * 1024) + 20 + 20 + 12, .hard_start_xmit = loopback_xmit, .hard_header = eth_header, @@ -221,16 +228,6 @@ struct net_device loopback_dev = { /* Setup and register the loopback device. */ int __init loopback_init(void) { - struct net_device_stats *stats; - - /* Can survive without statistics */ - stats = kmalloc(sizeof(struct net_device_stats), GFP_KERNEL); - if (stats) { - memset(stats, 0, sizeof(struct net_device_stats)); - loopback_dev.priv = stats; - loopback_dev.get_stats = &get_stats; - } - return register_netdev(&loopback_dev); }; -- cgit v1.2.3