<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/gateway_client.c | 28 +++++++++++++--------------- batman-adv/types.h | 2 +- 2 files changed, 14 insertions(+), 16 deletions(-)
diff --git a/batman-adv/gateway_client.c b/batman-adv/gateway_client.c index 429a013..8ce3a63 100644 --- a/batman-adv/gateway_client.c +++ b/batman-adv/gateway_client.c @@ -28,20 +28,18 @@ #include <linux/udp.h> #include <linux/if_vlan.h>
-static void gw_node_free_ref(struct kref *refcount) -{ - struct gw_node *gw_node; - - gw_node = container_of(refcount, struct gw_node, refcount); - kfree(gw_node); -} - static void gw_node_free_rcu(struct rcu_head *rcu) { struct gw_node *gw_node;
gw_node = container_of(rcu, struct gw_node, rcu); - kref_put(&gw_node->refcount, gw_node_free_ref); + kfree(gw_node); +} + +static void gw_node_free_ref(struct gw_node *gw_node) +{ + if (atomic_dec_and_test(&gw_node->refcount)) + call_rcu(&gw_node->rcu, gw_node_free_rcu); }
void *gw_get_selected(struct bat_priv *bat_priv) @@ -61,7 +59,7 @@ void gw_deselect(struct bat_priv *bat_priv) bat_priv->curr_gw = NULL;
if (gw_node) - kref_put(&gw_node->refcount, gw_node_free_ref); + gw_node_free_ref(gw_node); }
static struct gw_node *gw_select(struct bat_priv *bat_priv, @@ -69,8 +67,8 @@ static struct gw_node *gw_select(struct bat_priv *bat_priv, { struct gw_node *curr_gw_node = bat_priv->curr_gw;
- if (new_gw_node) - kref_get(&new_gw_node->refcount); + if (new_gw_node && !atomic_inc_not_zero(&new_gw_node->refcount)) + return NULL;
bat_priv->curr_gw = new_gw_node; return curr_gw_node; @@ -181,7 +179,7 @@ void gw_election(struct bat_priv *bat_priv)
/* the kfree() has to be outside of the rcu lock */ if (old_gw_node) - kref_put(&old_gw_node->refcount, gw_node_free_ref); + gw_node_free_ref(old_gw_node); }
void gw_check_election(struct bat_priv *bat_priv, struct orig_node *orig_node) @@ -242,7 +240,7 @@ static void gw_node_add(struct bat_priv *bat_priv, memset(gw_node, 0, sizeof(struct gw_node)); INIT_HLIST_NODE(&gw_node->list); gw_node->orig_node = orig_node; - kref_init(&gw_node->refcount); + atomic_set(&gw_node->refcount, 1);
spin_lock_bh(&bat_priv->gw_list_lock); hlist_add_head_rcu(&gw_node->list, &bat_priv->gw_list); @@ -325,7 +323,7 @@ void gw_node_purge(struct bat_priv *bat_priv) gw_deselect(bat_priv);
hlist_del_rcu(&gw_node->list); - call_rcu(&gw_node->rcu, gw_node_free_rcu); + gw_node_free_ref(gw_node); }
diff --git a/batman-adv/types.h b/batman-adv/types.h index e4a0462..ca5f20a 100644 --- a/batman-adv/types.h +++ b/batman-adv/types.h @@ -100,7 +100,7 @@ struct gw_node { struct hlist_node list; struct orig_node *orig_node; unsigned long deleted; - struct kref refcount; + atomic_t refcount; struct rcu_head rcu; };