[v2,16/18] batman-adv: Place kref_get for nc_path near use

Message ID 1468597173-25378-16-git-send-email-sven@narfation.org (mailing list archive)
State Accepted, archived
Commit 8427a98ac717dafb6d89412cedde3b983a05df46
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/network-coding.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
  

Comments

Marek Lindner July 19, 2016, 8:44 a.m. UTC | #1
On Friday, July 15, 2016 17:39:31 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/network-coding.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Applied in revision 8427a98.

Thanks,
Marek
  

Patch

diff --git a/net/batman-adv/network-coding.c b/net/batman-adv/network-coding.c
index 4f4cfe5..165cd27 100644
--- a/net/batman-adv/network-coding.c
+++ b/net/batman-adv/network-coding.c
@@ -978,7 +978,6 @@  static struct batadv_nc_path *batadv_nc_get_path(struct batadv_priv *bat_priv,
 	INIT_LIST_HEAD(&nc_path->packet_list);
 	spin_lock_init(&nc_path->packet_list_lock);
 	kref_init(&nc_path->refcount);
-	kref_get(&nc_path->refcount);
 	nc_path->last_valid = jiffies;
 	ether_addr_copy(nc_path->next_hop, dst);
 	ether_addr_copy(nc_path->prev_hop, src);
@@ -988,6 +987,7 @@  static struct batadv_nc_path *batadv_nc_get_path(struct batadv_priv *bat_priv,
 		   nc_path->next_hop);
 
 	/* Add nc_path to hash table */
+	kref_get(&nc_path->refcount);
 	hash_added = batadv_hash_add(hash, batadv_nc_hash_compare,
 				     batadv_nc_hash_choose, &nc_path_key,
 				     &nc_path->hash_entry);