From mboxrd@z Thu Jan 1 00:00:00 1970 From: Veaceslav Falico Subject: [PATCH v4 net-next 07/27] net: add for_each iterators through neighbour lower link's private Date: Tue, 24 Sep 2013 13:46:47 +0200 Message-ID: <1380023227-9576-8-git-send-email-vfalico@redhat.com> References: <1380023227-9576-1-git-send-email-vfalico@redhat.com> Cc: jiri@resnulli.us, Veaceslav Falico , "David S. Miller" , Eric Dumazet , Alexander Duyck To: netdev@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:49245 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751057Ab3IXLrH (ORCPT ); Tue, 24 Sep 2013 07:47:07 -0400 In-Reply-To: <1380023227-9576-1-git-send-email-vfalico@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: Add a possibility to iterate through netdev_adjacent's private, currently only for lower neighbours. Add both RCU and RTNL/other locking variants of iterators, and make the non-rcu variant to be safe from removal. CC: "David S. Miller" CC: Eric Dumazet CC: Jiri Pirko CC: Alexander Duyck Signed-off-by: Veaceslav Falico --- Notes: v3 -> v4: Make netdev_for_each_lower_private() be safe for the entry removal, by storing the ->next pointer in iter. v2 -> v3: No change. v1 -> v2: No changes. RFC -> v1: rename neighbour_dev_list/all_dev_list to adj_list/all_adj_list and rework the naming of functions - to make the use the pattern netdev_(all_)(lower|upper)_* . Also reword the commit message - I had to read it three times to understand :-/, and move it closer to the beginning of the patchset. include/linux/netdevice.h | 17 ++++++++++++++ net/core/dev.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 76 insertions(+), 1 deletion(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 75d5bea..168974e 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2833,6 +2833,23 @@ extern struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *d updev; \ updev = netdev_all_upper_get_next_dev_rcu(dev, &(iter))) +extern void *netdev_lower_get_next_private(struct net_device *dev, + struct list_head **iter); +extern void *netdev_lower_get_next_private_rcu(struct net_device *dev, + struct list_head **iter); + +#define netdev_for_each_lower_private(dev, priv, iter) \ + for (iter = (dev)->adj_list.lower.next, \ + priv = netdev_lower_get_next_private(dev, &(iter)); \ + priv; \ + priv = netdev_lower_get_next_private(dev, &(iter))) + +#define netdev_for_each_lower_private_rcu(dev, priv, iter) \ + for (iter = &(dev)->adj_list.lower, \ + priv = netdev_lower_get_next_private_rcu(dev, &(iter)); \ + priv; \ + priv = netdev_lower_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 c69ab74..0aa844a 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4466,7 +4466,8 @@ struct net_device *netdev_master_upper_dev_get(struct net_device *dev) } EXPORT_SYMBOL(netdev_master_upper_dev_get); -/* netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list +/** + * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list * @dev: device * @iter: list_head ** of the current position * @@ -4492,6 +4493,63 @@ struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev, EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu); /** + * netdev_lower_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. + */ +void *netdev_lower_get_next_private(struct net_device *dev, + struct list_head **iter) +{ + struct netdev_adjacent *lower; + + lower = list_entry(*iter, struct netdev_adjacent, list); + + if (&lower->list == &dev->adj_list.lower) + return NULL; + + if (iter) + *iter = lower->list.next; + + return lower->private; +} +EXPORT_SYMBOL(netdev_lower_get_next_private); + +/** + * netdev_lower_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. + */ +void *netdev_lower_get_next_private_rcu(struct net_device *dev, + struct list_head **iter) +{ + struct netdev_adjacent *lower; + + WARN_ON_ONCE(!rcu_read_lock_held()); + + lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); + + if (&lower->list == &dev->adj_list.lower) + return NULL; + + if (iter) + *iter = &lower->list; + + return lower->private; +} +EXPORT_SYMBOL(netdev_lower_get_next_private_rcu); + +/** * netdev_master_upper_dev_get_rcu - Get master upper device * @dev: device * -- 1.8.4