From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ying Xue Subject: [PATCH net-next 07/10] batman-adv: use __dev_get_by_index instead of dev_get_by_index to find interface Date: Tue, 14 Jan 2014 15:41:06 +0800 Message-ID: <1389685269-18600-8-git-send-email-ying.xue@windriver.com> References: <1389685269-18600-1-git-send-email-ying.xue@windriver.com> Mime-Version: 1.0 Content-Type: text/plain Cc: , , , , , , , , To: Return-path: In-Reply-To: <1389685269-18600-1-git-send-email-ying.xue@windriver.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org The following call chains indicate that batadv_is_on_batman_iface() is always under rtnl_lock protection as call_netdevice_notifier() is protected by rtnl_lock. So if __dev_get_by_index() rather than dev_get_by_index() is used to find interface handler in it, this would help us avoid to change interface reference counter. call_netdevice_notifier() batadv_hard_if_event() batadv_hardif_add_interface() batadv_is_valid_iface() batadv_is_on_batman_iface() Cc: Antonio Quartulli Signed-off-by: Ying Xue --- net/batman-adv/hard-interface.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c index bebd46c..115d14e 100644 --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -86,15 +86,13 @@ static bool batadv_is_on_batman_iface(const struct net_device *net_dev) return false; /* recurse over the parent device */ - parent_dev = dev_get_by_index(&init_net, net_dev->iflink); + parent_dev = __dev_get_by_index(&init_net, net_dev->iflink); /* if we got a NULL parent_dev there is something broken.. */ if (WARN(!parent_dev, "Cannot find parent device")) return false; ret = batadv_is_on_batman_iface(parent_dev); - if (parent_dev) - dev_put(parent_dev); return ret; } -- 1.7.9.5