<TODO: write a long monologue about every problem we have or could have or maybe never had and would have when we not have it>
Signed-off-by: Sven Eckelmann sven@narfation.org --- batman-adv/soft-interface.c | 34 ++++++++++++++++------------------ batman-adv/types.h | 2 +- 2 files changed, 17 insertions(+), 19 deletions(-)
diff --git a/batman-adv/soft-interface.c b/batman-adv/soft-interface.c index 145e0f7..9fb8a6a 100644 --- a/batman-adv/soft-interface.c +++ b/batman-adv/soft-interface.c @@ -79,20 +79,18 @@ int my_skb_head_push(struct sk_buff *skb, unsigned int len) return 0; }
-static void softif_neigh_free_ref(struct kref *refcount) -{ - struct softif_neigh *softif_neigh; - - softif_neigh = container_of(refcount, struct softif_neigh, refcount); - kfree(softif_neigh); -} - static void softif_neigh_free_rcu(struct rcu_head *rcu) { struct softif_neigh *softif_neigh;
softif_neigh = container_of(rcu, struct softif_neigh, rcu); - kref_put(&softif_neigh->refcount, softif_neigh_free_ref); + kfree(softif_neigh); +} + +static void softif_neigh_free_ref(struct softif_neigh *softif_neigh) +{ + if (atomic_dec_and_test(&softif_neigh->refcount)) + call_rcu(&softif_neigh->rcu, softif_neigh_free_rcu); }
void softif_neigh_purge(struct bat_priv *bat_priv) @@ -119,11 +117,10 @@ void softif_neigh_purge(struct bat_priv *bat_priv) softif_neigh->addr, softif_neigh->vid); softif_neigh_tmp = bat_priv->softif_neigh; bat_priv->softif_neigh = NULL; - kref_put(&softif_neigh_tmp->refcount, - softif_neigh_free_ref); + softif_neigh_free_ref(softif_neigh_tmp); }
- call_rcu(&softif_neigh->rcu, softif_neigh_free_rcu); + softif_neigh_free_ref(softif_neigh); }
spin_unlock_bh(&bat_priv->softif_neigh_lock); @@ -144,8 +141,11 @@ static struct softif_neigh *softif_neigh_get(struct bat_priv *bat_priv, if (softif_neigh->vid != vid) continue;
+ if (!atomic_inc_not_zero(&softif_neigh->refcount)) + continue; + softif_neigh->last_seen = jiffies; - goto found; + goto out; }
softif_neigh = kzalloc(sizeof(struct softif_neigh), GFP_ATOMIC); @@ -155,15 +155,13 @@ static struct softif_neigh *softif_neigh_get(struct bat_priv *bat_priv, memcpy(softif_neigh->addr, addr, ETH_ALEN); softif_neigh->vid = vid; softif_neigh->last_seen = jiffies; - kref_init(&softif_neigh->refcount); + atomic_set(&softif_neigh->refcount, 1);
INIT_HLIST_NODE(&softif_neigh->list); spin_lock_bh(&bat_priv->softif_neigh_lock); hlist_add_head_rcu(&softif_neigh->list, &bat_priv->softif_neigh_list); spin_unlock_bh(&bat_priv->softif_neigh_lock);
-found: - kref_get(&softif_neigh->refcount); out: rcu_read_unlock(); return softif_neigh; @@ -267,7 +265,7 @@ static void softif_batman_recv(struct sk_buff *skb, struct net_device *dev, softif_neigh->addr, softif_neigh->vid); softif_neigh_tmp = bat_priv->softif_neigh; bat_priv->softif_neigh = softif_neigh; - kref_put(&softif_neigh_tmp->refcount, softif_neigh_free_ref); + softif_neigh_free_ref(softif_neigh_tmp); /* we need to hold the additional reference */ goto err; } @@ -285,7 +283,7 @@ static void softif_batman_recv(struct sk_buff *skb, struct net_device *dev, }
out: - kref_put(&softif_neigh->refcount, softif_neigh_free_ref); + softif_neigh_free_ref(softif_neigh); err: kfree_skb(skb); return; diff --git a/batman-adv/types.h b/batman-adv/types.h index ca5f20a..8df6d9d 100644 --- a/batman-adv/types.h +++ b/batman-adv/types.h @@ -270,7 +270,7 @@ struct softif_neigh { uint8_t addr[ETH_ALEN]; unsigned long last_seen; short vid; - struct kref refcount; + atomic_t refcount; struct rcu_head rcu; };