@@ -2763,51 +2763,31 @@ void bond_activebackup_arp_mon(struct work_struct *work)
struct bonding *bond = container_of(work, struct bonding,
arp_work.work);
bool should_notify_peers = false;
- int delta_in_ticks;
- read_lock(&bond->lock);
-
- delta_in_ticks = msecs_to_jiffies(bond->params.arp_interval);
+ if (!rtnl_trylock())
+ goto re_arm;
- if (!bond_has_slaves(bond))
+ if (!bond_has_slaves(bond)) {
+ rtnl_unlock();
goto re_arm;
+ }
should_notify_peers = bond_should_notify_peers(bond);
- if (bond_ab_arp_inspect(bond)) {
- read_unlock(&bond->lock);
-
- /* Race avoidance with bond_close flush of workqueue */
- if (!rtnl_trylock()) {
- read_lock(&bond->lock);
- delta_in_ticks = 1;
- should_notify_peers = false;
- goto re_arm;
- }
-
- read_lock(&bond->lock);
-
+ if (bond_ab_arp_inspect(bond))
bond_ab_arp_commit(bond);
- read_unlock(&bond->lock);
- rtnl_unlock();
- read_lock(&bond->lock);
- }
-
bond_ab_arp_probe(bond);
-re_arm:
- if (bond->params.arp_interval)
- queue_delayed_work(bond->wq, &bond->arp_work, delta_in_ticks);
+ if (should_notify_peers)
+ call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, bond->dev);
- read_unlock(&bond->lock);
+ rtnl_unlock();
- if (should_notify_peers) {
- if (!rtnl_trylock())
- return;
- call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, bond->dev);
- rtnl_unlock();
- }
+re_arm:
+ if (bond->params.arp_interval)
+ queue_delayed_work(bond->wq, &bond->arp_work,
+ msecs_to_jiffies(bond->params.arp_interval));
}
/*-------------------------- netdev event handling --------------------------*/
The bond slave list may change when the monitor is running, the slave list is no longer protected by bond->lock, only protected by rtnl lock(), so we has 3 way to modify it: 1.add bond_master_upper_dev_link() and bond_upper_dev_unlink() in bond->lock, but it is unsafe to call call_netdevice_notifiers() in write lock. 2.remove unused bond->lock for monitor function, only use the exist rtnl lock(). 3.use rcu_read_lock() to protect it, of course, it will transform bond_for_each_slave to bond_for_each_slave_rcu() and performance is better, but in slow path, it is ignored. so I remove the bond->lock and move the rtnl lock to protect the whole monitor function. Signed-off-by: Ding Tianhong <dingtianhong@huawei.com> --- drivers/net/bonding/bond_main.c | 46 ++++++++++++----------------------------- 1 file changed, 13 insertions(+), 33 deletions(-)