From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: [PATCH 2/2] loopback: minor statistics optimization Date: Fri, 8 Sep 2006 11:20:56 -0700 Message-ID: <20060908112056.7ef03bac@localhost.localdomain> References: <20060908111613.12c1f9b8@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: "David S. Miller" , Jeff Garzik , netdev@vger.kernel.org Return-path: Received: from smtp.osdl.org ([65.172.181.4]:2203 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1750756AbWIHSVT (ORCPT ); Fri, 8 Sep 2006 14:21:19 -0400 To: Stephen Hemminger In-Reply-To: <20060908111613.12c1f9b8@localhost.localdomain> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Minor loopback enhancements for 2.6.19 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 --- linux-2.6.orig/drivers/net/loopback.c +++ linux-2.6/drivers/net/loopback.c @@ -161,15 +161,13 @@ static int loopback_xmit(struct sk_buff 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_stat return stats; } -static u32 loopback_get_link(struct net_device *dev) +static u32 always_on(struct net_device *dev) { return 1; } -static struct ethtool_ops loopback_ethtool_ops = { - .get_link = loopback_get_link, +static const struct ethtool_ops loopback_ethtool_ops = { + .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); };