From patchwork Sat Jan 16 09:29:53 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sven Eckelmann X-Patchwork-Id: 4969 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=79.140.41.39; helo=v3-1039.vlinux.de; envelope-from=sven@narfation.org; receiver=b.a.t.m.a.n@lists.open-mesh.org Authentication-Results: open-mesh.org; dmarc=pass header.from=narfation.org Authentication-Results: open-mesh.org; dkim=pass reason="1024-bit key; unprotected key" header.d=narfation.org header.i=@narfation.org header.b=Uh+QvSgG; dkim-adsp=pass; dkim-atps=neutral Received: from v3-1039.vlinux.de (narfation.org [79.140.41.39]) by open-mesh.org (Postfix) with ESMTPS id 397EC81B7C for ; Sat, 16 Jan 2016 10:30:13 +0100 (CET) Received: from sven-desktop.home.narfation.org (p200300C593C167FD0000000000002E16.dip0.t-ipconnect.de [IPv6:2003:c5:93c1:67fd::2e16]) by v3-1039.vlinux.de (Postfix) with ESMTPSA id A5117110116; Sat, 16 Jan 2016 10:30:12 +0100 (CET) Authentication-Results: v3-1039.vlinux.de; dmarc=none header.from=narfation.org DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=narfation.org; s=20121; t=1452936612; bh=dotX8OUb7mloy1UTzldVcOZcCUk5yhPWGvp+k2BXMAc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Uh+QvSgGMIwGgQFuCN5+uvpyEamErIL12zv9vRmxdD8lLKEbpK3bW0OvM3AXWHtwD xp9CSaAdrE74zG4hMCQJbar7rkagMoRNbbqrwgBYgYzGorgUIi9lWWpUUg6qJCuIpN NAD5L8z/LyJrkFgHSL+CgyanGzJ8RWyANJhdpgv4= From: Sven Eckelmann To: b.a.t.m.a.n@lists.open-mesh.org Date: Sat, 16 Jan 2016 10:29:53 +0100 Message-Id: <1452936598-28619-15-git-send-email-sven@narfation.org> X-Mailer: git-send-email 2.7.0.rc3 In-Reply-To: <1452936598-28619-1-git-send-email-sven@narfation.org> References: <1452936598-28619-1-git-send-email-sven@narfation.org> Subject: [B.A.T.M.A.N.] [PATCH v6 15/20] batman-adv: Convert batadv_neigh_node to kref X-BeenThere: b.a.t.m.a.n@lists.open-mesh.org X-Mailman-Version: 2.1.18 Precedence: list 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: Sat, 16 Jan 2016 09:30:13 -0000 batman-adv uses a self-written reference implementation which is just based on atomic_t. This is less obvious when reading the code than kref and therefore increases the change that the reference counting will be missed. Signed-off-by: Sven Eckelmann --- v6: - removed patches which are now applied in the branch next - rebased remaining patches on the patch "batman-adv: Avoid recursive call_rcu for batadv_nc_node" which was modified by Marek while he applied the patches (this unfortunately made some of the remaining patches "hard" to apply) v5: - add hack which allows to compile against stable kernel like 3.2.44 which also added the kref_get_unless_zero function v4: - fix function names in commit messages - fix double whitespace in batadv_tt_orig_list_entry_release kerneldoc - add extra patch for batadv_claim_free_ref kerneldoc fix - change the phrase "free it" in all *_free_ref/*_put functions to "release it" v3: - update copyright year v2: - split patchset into fixes and kref migration to make it easier when the decision is made where each patch will be applied net/batman-adv/bat_iv_ogm.c | 5 +++-- net/batman-adv/originator.c | 22 ++++++++++++---------- net/batman-adv/routing.c | 8 ++++---- net/batman-adv/types.h | 2 +- 4 files changed, 20 insertions(+), 17 deletions(-) diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c index 23ce90e..affcbb5 100644 --- a/net/batman-adv/bat_iv_ogm.c +++ b/net/batman-adv/bat_iv_ogm.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include #include @@ -1002,7 +1003,7 @@ batadv_iv_ogm_orig_update(struct batadv_priv *bat_priv, neigh_addr = tmp_neigh_node->addr; if (batadv_compare_eth(neigh_addr, ethhdr->h_source) && tmp_neigh_node->if_incoming == if_incoming && - atomic_inc_not_zero(&tmp_neigh_node->refcount)) { + kref_get_unless_zero(&tmp_neigh_node->refcount)) { if (WARN(neigh_node, "too many matching neigh_nodes")) batadv_neigh_node_free_ref(neigh_node); neigh_node = tmp_neigh_node; @@ -1161,7 +1162,7 @@ static int batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node, if (tmp_neigh_node->if_incoming != if_incoming) continue; - if (!atomic_inc_not_zero(&tmp_neigh_node->refcount)) + if (!kref_get_unless_zero(&tmp_neigh_node->refcount)) continue; neigh_node = tmp_neigh_node; diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c index 428983a..9e3dbd8 100644 --- a/net/batman-adv/originator.c +++ b/net/batman-adv/originator.c @@ -229,15 +229,17 @@ void batadv_hardif_neigh_free_ref(struct batadv_hardif_neigh_node *hardif_neigh) /** * batadv_neigh_node_release - release neigh_node from lists and queue for * free after rcu grace period - * @neigh_node: neigh neighbor to free + * @ref: kref pointer of the neigh_node */ -static void batadv_neigh_node_release(struct batadv_neigh_node *neigh_node) +static void batadv_neigh_node_release(struct kref *ref) { struct hlist_node *node_tmp; + struct batadv_neigh_node *neigh_node; struct batadv_hardif_neigh_node *hardif_neigh; struct batadv_neigh_ifinfo *neigh_ifinfo; struct batadv_algo_ops *bao; + neigh_node = container_of(ref, struct batadv_neigh_node, refcount); bao = neigh_node->orig_node->bat_priv->bat_algo_ops; hlist_for_each_entry_safe(neigh_ifinfo, node_tmp, @@ -262,14 +264,13 @@ static void batadv_neigh_node_release(struct batadv_neigh_node *neigh_node) } /** - * batadv_neigh_node_free_ref - decrement the neighbors refcounter - * and possibly release it + * batadv_neigh_node_free_ref - decrement the neighbors refcounter and possibly + * release it * @neigh_node: neigh neighbor to free */ void batadv_neigh_node_free_ref(struct batadv_neigh_node *neigh_node) { - if (atomic_dec_and_test(&neigh_node->refcount)) - batadv_neigh_node_release(neigh_node); + kref_put(&neigh_node->refcount, batadv_neigh_node_release); } /** @@ -298,7 +299,7 @@ batadv_orig_router_get(struct batadv_orig_node *orig_node, break; } - if (router && !atomic_inc_not_zero(&router->refcount)) + if (router && !kref_get_unless_zero(&router->refcount)) router = NULL; rcu_read_unlock(); @@ -491,7 +492,7 @@ batadv_neigh_node_get(const struct batadv_orig_node *orig_node, if (tmp_neigh_node->if_incoming != hard_iface) continue; - if (!atomic_inc_not_zero(&tmp_neigh_node->refcount)) + if (!kref_get_unless_zero(&tmp_neigh_node->refcount)) continue; res = tmp_neigh_node; @@ -649,7 +650,8 @@ batadv_neigh_node_new(struct batadv_orig_node *orig_node, neigh_node->orig_node = orig_node; /* extra reference for return */ - atomic_set(&neigh_node->refcount, 2); + kref_init(&neigh_node->refcount); + kref_get(&neigh_node->refcount); spin_lock_bh(&orig_node->neigh_list_lock); hlist_add_head_rcu(&neigh_node->list, &orig_node->neigh_list); @@ -1084,7 +1086,7 @@ batadv_find_best_neighbor(struct batadv_priv *bat_priv, best, if_outgoing) <= 0)) continue; - if (!atomic_inc_not_zero(&neigh->refcount)) + if (!kref_get_unless_zero(&neigh->refcount)) continue; if (best) diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index 4a5cd8b..205310b 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -73,7 +73,7 @@ static void _batadv_update_route(struct batadv_priv *bat_priv, rcu_read_lock(); curr_router = rcu_dereference(orig_ifinfo->router); - if (curr_router && !atomic_inc_not_zero(&curr_router->refcount)) + if (curr_router && !kref_get_unless_zero(&curr_router->refcount)) curr_router = NULL; rcu_read_unlock(); @@ -101,7 +101,7 @@ static void _batadv_update_route(struct batadv_priv *bat_priv, batadv_neigh_node_free_ref(curr_router); /* increase refcount of new best neighbor */ - if (neigh_node && !atomic_inc_not_zero(&neigh_node->refcount)) + if (neigh_node && !kref_get_unless_zero(&neigh_node->refcount)) neigh_node = NULL; spin_lock_bh(&orig_node->neigh_list_lock); @@ -505,7 +505,7 @@ batadv_find_router(struct batadv_priv *bat_priv, if (!cand_router) goto next; - if (!atomic_inc_not_zero(&cand_router->refcount)) { + if (!kref_get_unless_zero(&cand_router->refcount)) { cand_router = NULL; goto next; } @@ -524,7 +524,7 @@ batadv_find_router(struct batadv_priv *bat_priv, /* mark the first possible candidate */ if (!first_candidate) { - atomic_inc(&cand_router->refcount); + kref_get(&cand_router->refcount); kref_get(&cand->refcount); first_candidate = cand; first_candidate_router = cand_router; diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 6193c01..68ca39e 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -384,7 +384,7 @@ struct batadv_neigh_node { spinlock_t ifinfo_lock; /* protects ifinfo_list and its members */ struct batadv_hard_iface *if_incoming; unsigned long last_seen; - atomic_t refcount; + struct kref refcount; struct rcu_head rcu; };