Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758839Ab0DHPiH (ORCPT ); Thu, 8 Apr 2010 11:38:07 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:57241 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932756Ab0DHPiB (ORCPT ); Thu, 8 Apr 2010 11:38:01 -0400 Date: Thu, 8 Apr 2010 08:37:10 -0700 From: Stephen Hemminger To: Amerigo Wang Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bridge@lists.linux-foundation.org, Andy Gospodarek , Neil Horman , Jeff Moyer , Matt Mackall , bonding-devel@lists.sourceforge.net, Jay Vosburgh , David Miller Subject: Re: [v3 Patch 2/3] bridge: make bridge support netpoll Message-ID: <20100408083710.2b61ee44@nehalam> In-Reply-To: <20100408062246.4499.5670.sendpatchset@localhost.localdomain> References: <20100408062234.4499.17042.sendpatchset@localhost.localdomain> <20100408062246.4499.5670.sendpatchset@localhost.localdomain> Organization: Linux Foundation X-Mailer: Claws Mail 3.7.5 (GTK+ 2.18.3; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6896 Lines: 237 On Thu, 8 Apr 2010 02:18:58 -0400 Amerigo Wang wrote: > > Based on the previous patch, make bridge support netpoll by: > > 1) implement the 2 methods to support netpoll for bridge; > > 2) modify netpoll during forwarding packets via bridge; > > 3) disable netpoll support of bridge when a netpoll-unabled device > is added to bridge; > > 4) enable netpoll support when all underlying devices support netpoll. > > Cc: David Miller > Cc: Neil Horman > Cc: Stephen Hemminger > Cc: Matt Mackall > Signed-off-by: WANG Cong > > --- > > Index: linux-2.6/net/bridge/br_device.c > =================================================================== > --- linux-2.6.orig/net/bridge/br_device.c > +++ linux-2.6/net/bridge/br_device.c > @@ -13,8 +13,10 @@ > > #include > #include > +#include > #include > #include > +#include > > #include > #include "br_private.h" > @@ -162,6 +164,59 @@ static int br_set_tx_csum(struct net_dev > return 0; > } > > +#ifdef CONFIG_NET_POLL_CONTROLLER > +bool br_devices_support_netpoll(struct net_bridge *br) > +{ > + struct net_bridge_port *p; > + bool ret = true; > + int count = 0; > + unsigned long flags; > + > + spin_lock_irqsave(&br->lock, flags); > + list_for_each_entry(p, &br->port_list, list) { > + count++; > + if (p->dev->priv_flags & IFF_DISABLE_NETPOLL > + || !p->dev->netdev_ops->ndo_poll_controller) > + ret = false; > + } > + spin_unlock_irqrestore(&br->lock, flags); > + return count != 0 && ret; > +} > + > +static void br_poll_controller(struct net_device *br_dev) > +{ > + struct netpoll *np = br_dev->npinfo->netpoll; > + > + if (np->real_dev != br_dev) > + netpoll_poll_dev(np->real_dev); > +} > + > +void br_netpoll_cleanup(struct net_device *br_dev) > +{ > + struct net_bridge *br = netdev_priv(br_dev); > + struct net_bridge_port *p, *n; > + const struct net_device_ops *ops; > + > + br->dev->npinfo = NULL; > + list_for_each_entry_safe(p, n, &br->port_list, list) { > + if (p->dev) { > + ops = p->dev->netdev_ops; > + if (ops->ndo_netpoll_cleanup) > + ops->ndo_netpoll_cleanup(p->dev); > + else > + p->dev->npinfo = NULL; > + } > + } > +} > + > +#else > + > +void br_netpoll_cleanup(struct net_device *br_dev) > +{ > +} > + > +#endif Could you use more stub functions to eliminate #ifdef's in code. > static const struct ethtool_ops br_ethtool_ops = { > .get_drvinfo = br_getinfo, > .get_link = ethtool_op_get_link, > @@ -184,6 +239,10 @@ static const struct net_device_ops br_ne > .ndo_set_multicast_list = br_dev_set_multicast_list, > .ndo_change_mtu = br_change_mtu, > .ndo_do_ioctl = br_dev_ioctl, > +#ifdef CONFIG_NET_POLL_CONTROLLER > + .ndo_netpoll_cleanup = br_netpoll_cleanup, > + .ndo_poll_controller = br_poll_controller, > +#endif > }; > > void br_dev_setup(struct net_device *dev) > Index: linux-2.6/net/bridge/br_forward.c > =================================================================== > --- linux-2.6.orig/net/bridge/br_forward.c > +++ linux-2.6/net/bridge/br_forward.c > @@ -15,6 +15,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -50,7 +51,13 @@ int br_dev_queue_push_xmit(struct sk_buf > else { > skb_push(skb, ETH_HLEN); > > - dev_queue_xmit(skb); > +#ifdef CONFIG_NET_POLL_CONTROLLER > + if (skb->dev->priv_flags & IFF_IN_NETPOLL) { > + netpoll_send_skb(skb->dev->npinfo->netpoll, skb); > + skb->dev->priv_flags &= ~IFF_IN_NETPOLL; > + } else > +#endif There is no protection on dev->priv_flags for SMP access. It would better bit value in dev->state if you are using it as control flag. Then you could use if (unlikely(test_and_clear_bit(__IN_NETPOLL, &skb->dev->state))) netpoll_send_skb(...) > + dev_queue_xmit(skb); > } > } > > @@ -66,9 +73,23 @@ int br_forward_finish(struct sk_buff *sk > > static void __br_deliver(const struct net_bridge_port *to, struct sk_buff *skb) > { > +#ifdef CONFIG_NET_POLL_CONTROLLER > + struct net_bridge *br = to->br; > + if (br->dev->priv_flags & IFF_IN_NETPOLL) { > + struct netpoll *np; > + to->dev->npinfo = skb->dev->npinfo; > + np = skb->dev->npinfo->netpoll; > + np->real_dev = np->dev = to->dev; > + to->dev->priv_flags |= IFF_IN_NETPOLL; > + } > +#endif This is n hot path, so use unlikely() > skb->dev = to->dev; > NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev, > br_forward_finish); > +#ifdef CONFIG_NET_POLL_CONTROLLER > + if (skb->dev->npinfo) > + skb->dev->npinfo->netpoll->dev = br->dev; > +#endif > } > > static void __br_forward(const struct net_bridge_port *to, struct sk_buff *skb) > Index: linux-2.6/net/bridge/br_if.c > =================================================================== > --- linux-2.6.orig/net/bridge/br_if.c > +++ linux-2.6/net/bridge/br_if.c > @@ -13,6 +13,7 @@ > > #include > #include > +#include > #include > #include > #include > @@ -153,6 +154,14 @@ static void del_nbp(struct net_bridge_po > kobject_uevent(&p->kobj, KOBJ_REMOVE); > kobject_del(&p->kobj); > > +#ifdef CONFIG_NET_POLL_CONTROLLER > + if (br_devices_support_netpoll(br)) > + br->dev->priv_flags &= ~IFF_DISABLE_NETPOLL; > + if (dev->netdev_ops->ndo_netpoll_cleanup) > + dev->netdev_ops->ndo_netpoll_cleanup(dev); > + else > + dev->npinfo = NULL; > +#endif > call_rcu(&p->rcu, destroy_nbp_rcu); > } > > @@ -165,6 +174,8 @@ static void del_br(struct net_bridge *br > del_nbp(p); > } > > + br_netpoll_cleanup(br->dev); > + > del_timer_sync(&br->gc_timer); > > br_sysfs_delbr(br->dev); > @@ -438,6 +449,20 @@ int br_add_if(struct net_bridge *br, str > > kobject_uevent(&p->kobj, KOBJ_ADD); > > +#ifdef CONFIG_NET_POLL_CONTROLLER > + if (br_devices_support_netpoll(br)) { > + br->dev->priv_flags &= ~IFF_DISABLE_NETPOLL; > + if (br->dev->npinfo) > + dev->npinfo = br->dev->npinfo; > + } else if (!(br->dev->priv_flags & IFF_DISABLE_NETPOLL)) { > + br->dev->priv_flags |= IFF_DISABLE_NETPOLL; > + printk(KERN_INFO "New device %s does not support netpoll\n", > + dev->name); > + printk(KERN_INFO "Disabling netpoll for %s\n", > + br->dev->name); One message is sufficient. -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/