From: Jay Vosburgh Date: Wed, 21 Jul 2010 12:14:48 +0000 (+0000) Subject: bonding: don't lock when copying/clearing VLAN list on slave X-Git-Tag: firefly_0821_release~9833^2~1306^2~134 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=03dc2f4c525afb9488edb687c2e1f7057d59b40e;p=firefly-linux-kernel-4.4.55.git bonding: don't lock when copying/clearing VLAN list on slave When copying VLAN information to or removing from a slave during slave addition or removal, the bonding code currently holds the bond->lock for write to prevent concurrent modification of the vlan_list / vlgrp. This is unnecessary, as all of these operations occur under RTNL. Holding the bond->lock also caused might_sleep issues for some drivers' ndo_vlan_* functions. This patch removes the extra locking. Problem reported by Michael Chan Signed-off-by: Jay Vosburgh Cc: Michael Chan Signed-off-by: David S. Miller --- diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index f3b01ce4f629..2cc4cfc31892 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -570,10 +570,8 @@ static void bond_add_vlans_on_slave(struct bonding *bond, struct net_device *sla struct vlan_entry *vlan; const struct net_device_ops *slave_ops = slave_dev->netdev_ops; - write_lock_bh(&bond->lock); - if (!bond->vlgrp) - goto out; + return; if ((slave_dev->features & NETIF_F_HW_VLAN_RX) && slave_ops->ndo_vlan_rx_register) @@ -581,13 +579,10 @@ static void bond_add_vlans_on_slave(struct bonding *bond, struct net_device *sla if (!(slave_dev->features & NETIF_F_HW_VLAN_FILTER) || !(slave_ops->ndo_vlan_rx_add_vid)) - goto out; + return; list_for_each_entry(vlan, &bond->vlan_list, vlan_list) slave_ops->ndo_vlan_rx_add_vid(slave_dev, vlan->vlan_id); - -out: - write_unlock_bh(&bond->lock); } static void bond_del_vlans_from_slave(struct bonding *bond, @@ -597,10 +592,8 @@ static void bond_del_vlans_from_slave(struct bonding *bond, struct vlan_entry *vlan; struct net_device *vlan_dev; - write_lock_bh(&bond->lock); - if (!bond->vlgrp) - goto out; + return; if (!(slave_dev->features & NETIF_F_HW_VLAN_FILTER) || !(slave_ops->ndo_vlan_rx_kill_vid)) @@ -621,9 +614,6 @@ unreg: if ((slave_dev->features & NETIF_F_HW_VLAN_RX) && slave_ops->ndo_vlan_rx_register) slave_ops->ndo_vlan_rx_register(slave_dev, NULL); - -out: - write_unlock_bh(&bond->lock); } /*------------------------------- Link status -------------------------------*/