From patchwork Sun Nov 21 19:54:28 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sven Eckelmann X-Patchwork-Id: 556 Return-Path: Received: from mail.gmx.net (mailout-de.gmx.net [213.165.64.22]) by open-mesh.org (Postfix) with SMTP id 84C3A1544D6 for ; Sun, 21 Nov 2010 20:54:17 +0100 (CET) Received: (qmail invoked by alias); 21 Nov 2010 19:54:15 -0000 Received: from i59F6D67A.versanet.de (EHLO sven-desktop.lazhur.ath.cx) [89.246.214.122] by mail.gmx.net (mp004) with SMTP; 21 Nov 2010 20:54:15 +0100 X-Authenticated: #15668376 X-Provags-ID: V01U2FsdGVkX1+rHZo+MkerBWSnkP63MV8LYrB9D/u6uyJE8Iligs 054icWTbvn+kw2 From: Sven Eckelmann To: b.a.t.m.a.n@lists.open-mesh.org Date: Sun, 21 Nov 2010 20:54:28 +0100 Message-Id: <1290369268-9525-1-git-send-email-sven.eckelmann@gmx.de> X-Mailer: git-send-email 1.7.2.3 X-Y-GMX-Trusted: 0 Subject: [B.A.T.M.A.N.] [PATCH] batman-adv: Don't remove interface with spinlock held X-BeenThere: b.a.t.m.a.n@lists.open-mesh.org X-Mailman-Version: 2.1.11 Precedence: list Reply-To: The list for a Better Approach To Mobile Ad-hoc Networking List-Id: The list for a Better Approach To Mobile Ad-hoc Networking List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 21 Nov 2010 19:54:17 -0000 We call a lot of the netdevice code when holding if_list_lock which will spin the whole time. This is not necessary because we only want to protect the access to the list to be serialized. An extra queue can be used which hold all interfaces which should be removed and then use that queue without any locks for netdevice cleanup. Signed-off-by: Sven Eckelmann --- batman-adv/hard-interface.c | 19 +++++++++++++------ 1 files changed, 13 insertions(+), 6 deletions(-) diff --git a/batman-adv/hard-interface.c b/batman-adv/hard-interface.c index e22f0dd..bf98b90 100644 --- a/batman-adv/hard-interface.c +++ b/batman-adv/hard-interface.c @@ -469,9 +469,6 @@ static void hardif_remove_interface(struct batman_if *batman_if) return; batman_if->if_status = IF_TO_BE_REMOVED; - - /* caller must take if_list_lock */ - list_del_rcu(&batman_if->list); sysfs_del_hardif(&batman_if->hardif_obj); call_rcu(&batman_if->rcu, hardif_free_rcu); } @@ -479,13 +476,21 @@ static void hardif_remove_interface(struct batman_if *batman_if) void hardif_remove_interfaces(void) { struct batman_if *batman_if, *batman_if_tmp; + struct list_head if_list_queue; + + INIT_LIST_HEAD(&if_list_queue); - rtnl_lock(); spin_lock(&if_list_lock); list_for_each_entry_safe(batman_if, batman_if_tmp, &if_list, list) { - hardif_remove_interface(batman_if); + list_del_rcu(&batman_if->list); + list_add_tail(&batman_if->list, &if_list_queue); } spin_unlock(&if_list_lock); + + rtnl_lock(); + list_for_each_entry_safe(batman_if, batman_if_tmp, &if_list_queue, list) { + hardif_remove_interface(batman_if); + } rtnl_unlock(); } @@ -512,8 +517,10 @@ static int hard_if_event(struct notifier_block *this, break; case NETDEV_UNREGISTER: spin_lock(&if_list_lock); - hardif_remove_interface(batman_if); + list_del_rcu(&batman_if->list); spin_unlock(&if_list_lock); + + hardif_remove_interface(batman_if); break; case NETDEV_CHANGEMTU: if (batman_if->soft_iface)