From patchwork Wed Feb 10 15:57:25 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Antonio Quartulli X-Patchwork-Id: 5032 Return-Path: Received-SPF: Permerror (SPF Permanent Error: Two or more type TXT spf records found.) identity=mailfrom; client-ip=5.148.176.60; helo=s2.neomailbox.net; envelope-from=a@unstable.cc; receiver=b.a.t.m.a.n@lists.open-mesh.org Authentication-Results: open-mesh.org; dmarc=none header.from=unstable.cc Received: from s2.neomailbox.net (s2.neomailbox.net [5.148.176.60]) by open-mesh.org (Postfix) with ESMTPS id 8877481D4D for ; Wed, 10 Feb 2016 17:18:38 +0100 (CET) From: Antonio Quartulli To: davem@davemloft.net Date: Wed, 10 Feb 2016 23:57:25 +0800 Message-Id: <1455119847-5862-20-git-send-email-a@unstable.cc> In-Reply-To: <1455119847-5862-1-git-send-email-a@unstable.cc> References: <1455119847-5862-1-git-send-email-a@unstable.cc> Cc: netdev@vger.kernel.org, b.a.t.m.a.n@lists.open-mesh.org, Antonio Quartulli , Marek Lindner Subject: [B.A.T.M.A.N.] [PATCH 19/21] batman-adv: Convert batadv_orig_node_vlan 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: Wed, 10 Feb 2016 16:18:38 -0000 From: Sven Eckelmann 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 Signed-off-by: Marek Lindner Signed-off-by: Antonio Quartulli --- net/batman-adv/originator.c | 26 ++++++++++++++++++++------ net/batman-adv/types.h | 2 +- 2 files changed, 21 insertions(+), 7 deletions(-) diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c index bf27007a574a..8b2ef8de93e9 100644 --- a/net/batman-adv/originator.c +++ b/net/batman-adv/originator.c @@ -82,7 +82,7 @@ batadv_orig_node_vlan_get(struct batadv_orig_node *orig_node, if (tmp->vid != vid) continue; - if (!atomic_inc_not_zero(&tmp->refcount)) + if (!kref_get_unless_zero(&tmp->refcount)) continue; vlan = tmp; @@ -123,7 +123,8 @@ batadv_orig_node_vlan_new(struct batadv_orig_node *orig_node, if (!vlan) goto out; - atomic_set(&vlan->refcount, 2); + kref_init(&vlan->refcount); + kref_get(&vlan->refcount); vlan->vid = vid; hlist_add_head_rcu(&vlan->list, &orig_node->vlan_list); @@ -135,14 +136,27 @@ out: } /** - * batadv_orig_node_vlan_free_ref - decrement the refcounter and possibly free - * the originator-vlan object + * batadv_orig_node_vlan_release - release originator-vlan object from lists + * and queue for free after rcu grace period + * @ref: kref pointer of the originator-vlan object + */ +static void batadv_orig_node_vlan_release(struct kref *ref) +{ + struct batadv_orig_node_vlan *orig_vlan; + + orig_vlan = container_of(ref, struct batadv_orig_node_vlan, refcount); + + kfree_rcu(orig_vlan, rcu); +} + +/** + * batadv_orig_node_vlan_free_ref - decrement the refcounter and possibly + * release the originator-vlan object * @orig_vlan: the originator-vlan object to release */ void batadv_orig_node_vlan_free_ref(struct batadv_orig_node_vlan *orig_vlan) { - if (atomic_dec_and_test(&orig_vlan->refcount)) - kfree_rcu(orig_vlan, rcu); + kref_put(&orig_vlan->refcount, batadv_orig_node_vlan_release); } int batadv_originator_init(struct batadv_priv *bat_priv) diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 74cb26372ed1..504f3dbdbcc1 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -197,7 +197,7 @@ struct batadv_orig_node_vlan { unsigned short vid; struct batadv_vlan_tt tt; struct hlist_node list; - atomic_t refcount; + struct kref refcount; struct rcu_head rcu; };