diff mbox

[v2,13/18] batman-adv: Place kref_get for hard_iface near use

Message ID 1468597173-25378-13-git-send-email-sven@narfation.org (mailing list archive)
State Accepted, archived
Commit a1ca9847e553f6cf66e7e6f0f7b0d0c18a75d5dc
Delegated to: Marek Lindner
Headers

Commit Message

Sven Eckelmann July 15, 2016, 3:39 p.m. UTC 
  It is hard to understand why the refcnt is increased when it isn't done
near the actual place the new reference is used. So using kref_get right
before the place which requires the reference and in the same function
helps to avoid accidental problems causedy incorrect reference counting.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
---
v2:
 - split patch based on type

 net/batman-adv/hard-interface.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

Comments

Marek Lindner July 19, 2016, 8:40 a.m. UTC | #1 
On Friday, July 15, 2016 17:39:28 Sven Eckelmann wrote:
> It is hard to understand why the refcnt is increased when it isn't done
> near the actual place the new reference is used. So using kref_get right
> before the place which requires the reference and in the same function
> helps to avoid accidental problems causedy incorrect reference counting.
> 
> Signed-off-by: Sven Eckelmann <sven@narfation.org>
> ---
> v2:
>  - split patch based on type
> 
>  net/batman-adv/hard-interface.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)

Applied in revision a1ca984.

Thanks,
Marek
diff mbox

Patch

diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c
index 714af8e..adb0377 100644
--- a/net/batman-adv/hard-interface.c
+++ b/net/batman-adv/hard-interface.c
@@ -658,6 +658,7 @@  batadv_hardif_add_interface(struct net_device *net_dev)
 	INIT_HLIST_HEAD(&hard_iface->neigh_list);
 
 	spin_lock_init(&hard_iface->neigh_list_lock);
+	kref_init(&hard_iface->refcount);
 
 	hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT;
 	if (batadv_is_wifi_netdev(net_dev))
@@ -665,11 +666,8 @@  batadv_hardif_add_interface(struct net_device *net_dev)
 
 	batadv_v_hardif_init(hard_iface);
 
-	/* extra reference for return */
-	kref_init(&hard_iface->refcount);
-	kref_get(&hard_iface->refcount);
-
 	batadv_check_known_mac_addr(hard_iface->net_dev);
+	kref_get(&hard_iface->refcount);
 	list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
 
 	return hard_iface;