summaryrefslogtreecommitdiffstats
path: root/net/batman-adv/hash.h
diff options
context:
space:
mode:
authorMatthias Schiffer <mschiffer@universe-factory.net>2012-05-08 22:31:57 +0200
committerAntonio Quartulli <ordex@autistici.org>2012-06-18 18:01:06 +0200
commit75c5a2e788ab02f67931442e8dcbc854ae7252d1 (patch)
treef1ae84324fe9990fa8b04edd17384e644d8cb73b /net/batman-adv/hash.h
parentbatman-adv: use DBG_ALL in log_level sysfs definition (diff)
downloadlinux-75c5a2e788ab02f67931442e8dcbc854ae7252d1.tar.xz
linux-75c5a2e788ab02f67931442e8dcbc854ae7252d1.zip
batman-adv: fix locking in hash_add()
To ensure an entry isn't added twice all comparisons have to be protected by the hash line write spinlock. This doesn't really hurt as the case that it is tried to add an element already present to the hash shouldn't occur very often, so in most cases the lock would have have to be taken anyways. Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net> Acked-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Sven Eckelmann <sven@narfation.org>
Diffstat (limited to 'net/batman-adv/hash.h')
-rw-r--r--net/batman-adv/hash.h15
1 files changed, 6 insertions, 9 deletions
diff --git a/net/batman-adv/hash.h b/net/batman-adv/hash.h
index 93b3c71aeaf8..3d67ce49fc31 100644
--- a/net/batman-adv/hash.h
+++ b/net/batman-adv/hash.h
@@ -110,26 +110,23 @@ static inline int hash_add(struct hashtable_t *hash,
head = &hash->table[index];
list_lock = &hash->list_locks[index];
- rcu_read_lock();
- __hlist_for_each_rcu(node, head) {
+ spin_lock_bh(list_lock);
+
+ hlist_for_each(node, head) {
if (!compare(node, data))
continue;
ret = 1;
- goto err_unlock;
+ goto unlock;
}
- rcu_read_unlock();
/* no duplicate found in list, add new element */
- spin_lock_bh(list_lock);
hlist_add_head_rcu(data_node, head);
- spin_unlock_bh(list_lock);
ret = 0;
- goto out;
-err_unlock:
- rcu_read_unlock();
+unlock:
+ spin_unlock_bh(list_lock);
out:
return ret;
}