hardif_list_lock is unneccessary because we already ensure that no
multiple admin operations can take place through rtnl_lock.
hardif_list_lock only adds additional overhead and complexity.
Critical functions now check whether they are called with rtnl_lock
using ASSERT_RTNL.
Signed-off-by: Sven Eckelmann <s...@narfation.org>
---
Splitted the first patch to keep Linus' fame. There should be no difference
(after all patches are applied) between the first and the second version.
hard-interface.c | 14 ++++----------
1 files changed, 4 insertions(+), 10 deletions(-)
diff --git a/hard-interface.c b/hard-interface.c
index c6edf0a..ebd7ef0 100644
--- a/hard-interface.c
+++ b/hard-interface.c
@@ -31,9 +31,6 @@
#include <linux/if_arp.h>
-/* protect update critical side of hardif_list - but not the content */
-static DEFINE_SPINLOCK(hardif_list_lock);
-
static int batman_skb_recv(struct sk_buff *skb,
struct net_device *dev,
@@ -432,6 +429,8 @@ static struct hard_iface *hardif_add_interface(struct
net_device *net_dev)
struct hard_iface *hard_iface;
int ret;
+ ASSERT_RTNL();
+
ret = is_valid_iface(net_dev);
if (ret != 1)
goto out;
@@ -458,10 +457,7 @@ static struct hard_iface *hardif_add_interface(struct
net_device *net_dev)
atomic_set(&hard_iface->refcount, 2);
check_known_mac_addr(hard_iface->net_dev);
-
- spin_lock(&hardif_list_lock);
list_add_tail_rcu(&hard_iface->list, &hardif_list);
- spin_unlock(&hardif_list_lock);
return hard_iface;
@@ -475,6 +471,8 @@ out:
static void hardif_remove_interface(struct hard_iface *hard_iface)
{
+ ASSERT_RTNL();
+
/* first deactivate interface */
if (hard_iface->if_status != IF_NOT_IN_USE)
hardif_disable_interface(hard_iface);
@@ -492,13 +490,11 @@ void hardif_remove_interfaces(void)
struct hard_iface *hard_iface, *hard_iface_tmp;
rtnl_lock();
- spin_lock(&hardif_list_lock);
list_for_each_entry_safe(hard_iface, hard_iface_tmp,
&hardif_list, list) {
list_del_rcu(&hard_iface->list);
hardif_remove_interface(hard_iface);
}
- spin_unlock(&hardif_list_lock);
rtnl_unlock();
}
@@ -524,9 +520,7 @@ static int hard_if_event(struct notifier_block *this,
hardif_deactivate_interface(hard_iface);
break;
case NETDEV_UNREGISTER:
- spin_lock(&hardif_list_lock);
list_del_rcu(&hard_iface->list);
- spin_unlock(&hardif_list_lock);
hardif_remove_interface(hard_iface);
break;
--
1.7.4.4
