From mboxrd@z Thu Jan 1 00:00:00 1970 From: Veaceslav Falico Subject: [PATCH RFC net-next 12/21] net: add for_each iterators through neighbour lower link's private Date: Mon, 2 Sep 2013 23:39:16 +0200 Message-ID: <1378157965-17537-13-git-send-email-vfalico@redhat.com> References: <1378157965-17537-1-git-send-email-vfalico@redhat.com> Cc: Veaceslav Falico , "David S. Miller" , Eric Dumazet , Jiri Pirko , Alexander Duyck To: netdev@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:10558 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759065Ab3IBVj3 (ORCPT ); Mon, 2 Sep 2013 17:39:29 -0400 In-Reply-To: <1378157965-17537-1-git-send-email-vfalico@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: Currently we can only iterate through the devices itself, however it'd be really costy to first get the next device and then search for the link and get its private - which is a common method to go through slaves of a device. Add both RCU and RTNL/other locking variants of iterators. CC: "David S. Miller" CC: Eric Dumazet CC: Jiri Pirko CC: Alexander Duyck Signed-off-by: Veaceslav Falico --- include/linux/netdevice.h | 17 ++++++++++++ net/core/dev.c | 66 +++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 83 insertions(+) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index ef1ddee..1a149ef 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2788,6 +2788,23 @@ extern struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev, updev; \ updev = netdev_upper_get_next_dev_rcu(dev, &(iter))) +extern void *netdev_lower_neigh_get_next_private(struct net_device *dev, + struct list_head **iter); +extern void *netdev_lower_neigh_get_next_private_rcu(struct net_device *dev, + struct list_head **iter); + +#define netdev_for_each_lower_neigh_private(dev, priv, iter) \ + for (iter = &(dev)->neighbour_dev_list.lower, \ + priv = netdev_lower_neigh_get_next_private(dev, &(iter)); \ + priv; \ + priv = netdev_lower_neigh_get_next_private(dev, &(iter))) + +#define netdev_for_each_lower_neigh_private_rcu(dev, priv, iter) \ + for (iter = &(dev)->neighbour_dev_list.lower, \ + priv = netdev_lower_neigh_get_next_private_rcu(dev, &(iter)); \ + priv; \ + priv = netdev_lower_neigh_get_next_private_rcu(dev, &(iter))) + extern struct net_device *netdev_master_upper_dev_get(struct net_device *dev); extern struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev); extern int netdev_upper_dev_link(struct net_device *dev, diff --git a/net/core/dev.c b/net/core/dev.c index 1c3e98d..55f8ac4 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4555,6 +4555,72 @@ struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev, } EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu); +/* netdev_lower_neigh_get_next_private - Get the next ->private from the + * lower neighbour list + * @dev: device + * @iter: list_head ** of the current position + * + * Gets the next netdev_adjacent->private from the dev's lower neighbour + * list, starting from iter position. The caller must hold either hold the + * RTNL lock or its own locking that guarantees that the neighbour lower + * list will remain unchainged. If iter is NULL - return the first private. + */ +void *netdev_lower_neigh_get_next_private(struct net_device *dev, + struct list_head **iter) +{ + struct netdev_adjacent *lower; + + if (iter) + lower = list_entry((*iter)->next, struct netdev_adjacent, + list); + else + lower = list_entry(dev->neighbour_dev_list.lower.next, + struct netdev_adjacent, list); + + if (&lower->list == &dev->neighbour_dev_list.lower) + return NULL; + + if (iter) + *iter = &lower->list; + + return lower->private; +} +EXPORT_SYMBOL(netdev_lower_neigh_get_next_private); + +/* netdev_lower_neigh_get_next_private_rcu - Get the next ->private from the + * lower neighbour list, RCU + * variant + * @dev: device + * @iter: list_head ** of the current position + * + * Gets the next netdev_adjacent->private from the dev's lower neighbour + * list, starting from iter position. The caller must hold RCU read lock. + * If iter is NULL - returns the first private. + */ +void *netdev_lower_neigh_get_next_private_rcu(struct net_device *dev, + struct list_head **iter) +{ + struct netdev_adjacent *lower; + + WARN_ON_ONCE(!rcu_read_lock_held()); + + if (iter) + lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, + list); + else + lower = list_entry_rcu(dev->neighbour_dev_list.lower.next, + struct netdev_adjacent, list); + + if (&lower->list == &dev->neighbour_dev_list.lower) + return NULL; + + if (iter) + *iter = &lower->list; + + return lower->private; +} +EXPORT_SYMBOL(netdev_lower_neigh_get_next_private_rcu); + /** * netdev_master_upper_dev_get_rcu - Get master upper device * @dev: device -- 1.8.4