From patchwork Sat Jan 16 09:29:42 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sven Eckelmann X-Patchwork-Id: 4955 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=sYuciqSP; 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 D97D881B6E for ; Sat, 16 Jan 2016 10:30:04 +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 6B91B1100E7; Sat, 16 Jan 2016 10:30:04 +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=1452936604; bh=hjU5U0o1AXwPONl1CtqXOcu9g+caeUQ1th/1YfPmwEU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sYuciqSPfBxJtWfNsSld2DNZMh5VL05Fqx0pEVj2GAWR5C7SmUJSUu7ACrEl7tUhY wWWwDl7yn4T61qxwDMEOrjqX6Wa88OBY7yvnPLLOuYpcnZqd/1HaCVC2pqYPJbz2d9 6HBpbhkASPTO1/SiZuNPWmTSUTR4XzXHEGOZhcZY= From: Sven Eckelmann To: b.a.t.m.a.n@lists.open-mesh.org Date: Sat, 16 Jan 2016 10:29:42 +0100 Message-Id: <1452936598-28619-4-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 04/20] batman-adv: Convert batadv_softif_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: Sat, 16 Jan 2016 09:30:05 -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/soft-interface.c | 33 +++++++++++++++++++++++---------- net/batman-adv/sysfs.c | 3 ++- net/batman-adv/types.h | 2 +- 3 files changed, 26 insertions(+), 12 deletions(-) diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c index 4bf35b8..d4490ff 100644 --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -30,6 +30,7 @@ #include #include #include +#include #include #include #include @@ -478,8 +479,26 @@ out: } /** + * batadv_softif_vlan_release - release vlan from lists and queue for free after + * rcu grace period + * @ref: kref pointer of the vlan object + */ +static void batadv_softif_vlan_release(struct kref *ref) +{ + struct batadv_softif_vlan *vlan; + + vlan = container_of(ref, struct batadv_softif_vlan, refcount); + + spin_lock_bh(&vlan->bat_priv->softif_vlan_list_lock); + hlist_del_rcu(&vlan->list); + spin_unlock_bh(&vlan->bat_priv->softif_vlan_list_lock); + + kfree_rcu(vlan, rcu); +} + +/** * batadv_softif_vlan_free_ref - decrease the vlan object refcounter and - * possibly free it + * possibly release it * @vlan: the vlan object to release */ void batadv_softif_vlan_free_ref(struct batadv_softif_vlan *vlan) @@ -487,13 +506,7 @@ void batadv_softif_vlan_free_ref(struct batadv_softif_vlan *vlan) if (!vlan) return; - if (atomic_dec_and_test(&vlan->refcount)) { - spin_lock_bh(&vlan->bat_priv->softif_vlan_list_lock); - hlist_del_rcu(&vlan->list); - spin_unlock_bh(&vlan->bat_priv->softif_vlan_list_lock); - - kfree_rcu(vlan, rcu); - } + kref_put(&vlan->refcount, batadv_softif_vlan_release); } /** @@ -514,7 +527,7 @@ struct batadv_softif_vlan *batadv_softif_vlan_get(struct batadv_priv *bat_priv, if (vlan_tmp->vid != vid) continue; - if (!atomic_inc_not_zero(&vlan_tmp->refcount)) + if (!kref_get_unless_zero(&vlan_tmp->refcount)) continue; vlan = vlan_tmp; @@ -549,7 +562,7 @@ int batadv_softif_create_vlan(struct batadv_priv *bat_priv, unsigned short vid) vlan->bat_priv = bat_priv; vlan->vid = vid; - atomic_set(&vlan->refcount, 1); + kref_init(&vlan->refcount); atomic_set(&vlan->ap_isolation, 0); diff --git a/net/batman-adv/sysfs.c b/net/batman-adv/sysfs.c index 964fc59..ab4382b 100644 --- a/net/batman-adv/sysfs.c +++ b/net/batman-adv/sysfs.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include #include @@ -97,7 +98,7 @@ batadv_kobj_to_vlan(struct batadv_priv *bat_priv, struct kobject *obj) if (vlan_tmp->kobj != obj) continue; - if (!atomic_inc_not_zero(&vlan_tmp->refcount)) + if (!kref_get_unless_zero(&vlan_tmp->refcount)) continue; vlan = vlan_tmp; diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 06c3888..868f6b5 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -746,7 +746,7 @@ struct batadv_softif_vlan { atomic_t ap_isolation; /* boolean */ struct batadv_vlan_tt tt; struct hlist_node list; - atomic_t refcount; + struct kref refcount; struct rcu_head rcu; };