diff options
| author | dingtianhong <dingtianhong@huawei.com> | 2013-10-24 07:09:12 +0400 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2013-10-28 00:36:29 +0400 |
| commit | 2d0dafb0152a6ac61cd31d38c3ef3d49463b6a57 (patch) | |
| tree | 0d34b9c5d8a036f1f6fa2a2bbddc73f0942f0e70 /drivers/net | |
| parent | 6b6c526147bb00b5788a2f48463481dd30c29b71 (diff) | |
| download | linux-2d0dafb0152a6ac61cd31d38c3ef3d49463b6a57.tar.xz | |
bonding: remove bond read lock for bond_alb_monitor()
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 have 3 ways 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 existing 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>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/bonding/bond_alb.c | 20 |
1 files changed, 4 insertions, 16 deletions
diff --git a/drivers/net/bonding/bond_alb.c b/drivers/net/bonding/bond_alb.c index 02872405d35d..5d79f5e529e0 100644 --- a/drivers/net/bonding/bond_alb.c +++ b/drivers/net/bonding/bond_alb.c @@ -1495,11 +1495,13 @@ void bond_alb_monitor(struct work_struct *work) struct list_head *iter; struct slave *slave; - read_lock(&bond->lock); + if (!rtnl_trylock()) + goto re_arm; if (!bond_has_slaves(bond)) { bond_info->tx_rebalance_counter = 0; bond_info->lp_counter = 0; + rtnl_unlock(); goto re_arm; } @@ -1548,16 +1550,6 @@ void bond_alb_monitor(struct work_struct *work) if (bond_info->primary_is_promisc && (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) { - /* - * dev_set_promiscuity requires rtnl and - * nothing else. Avoid race with bond_close. - */ - read_unlock(&bond->lock); - if (!rtnl_trylock()) { - read_lock(&bond->lock); - goto re_arm; - } - bond_info->rlb_promisc_timeout_counter = 0; /* If the primary was set to promiscuous mode @@ -1566,9 +1558,6 @@ void bond_alb_monitor(struct work_struct *work) */ dev_set_promiscuity(bond->curr_active_slave->dev, -1); bond_info->primary_is_promisc = 0; - - rtnl_unlock(); - read_lock(&bond->lock); } if (bond_info->rlb_rebalance) { @@ -1591,10 +1580,9 @@ void bond_alb_monitor(struct work_struct *work) } } + rtnl_unlock(); re_arm: queue_delayed_work(bond->wq, &bond->alb_work, alb_delta_in_ticks); - - read_unlock(&bond->lock); } /* assumption: called before the slave is attached to the bond |