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;
};