From 7864a1adf7291993d74923fdd0a45459ce9da27e Mon Sep 17 00:00:00 2001
From: Veaceslav Falico <vfalico@redhat.com>
Date: Mon, 5 Aug 2013 14:56:06 +0200
Subject: [PATCH] bonding: remove locking from bond_set_rx_mode()
We're already protected by RTNL lock, so nothing can happen to bond/its
slaves, and thus the locking is useless here (both bond->lock and
bond->curr_active_slave).
Also, add ASSERT_RTNL() both to bond_set_rx_mode() and bond_hw_addr_swap()
to catch possible uses of it without RTNL locking.
This patch also saves us from a lockdep false-positive in
bond_set_rx_mode() vs bond_hw_addr_swap().
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/net/bonding/bond_main.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index d58237b3dd98d..5697043eafbda 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -776,6 +776,8 @@ static void bond_hw_addr_flush(struct net_device *bond_dev,
static void bond_hw_addr_swap(struct bonding *bond, struct slave *new_active,
struct slave *old_active)
{
+ ASSERT_RTNL();
+
if (old_active) {
if (bond->dev->flags & IFF_PROMISC)
dev_set_promiscuity(old_active->dev, -1);
@@ -3551,24 +3553,20 @@ static void bond_set_rx_mode(struct net_device *bond_dev)
struct bonding *bond = netdev_priv(bond_dev);
struct slave *slave;
- read_lock(&bond->lock);
+ ASSERT_RTNL();
if (USES_PRIMARY(bond->params.mode)) {
- read_lock(&bond->curr_slave_lock);
- slave = bond->curr_active_slave;
+ slave = rtnl_dereference(bond->curr_active_slave);
if (slave) {
dev_uc_sync(slave->dev, bond_dev);
dev_mc_sync(slave->dev, bond_dev);
}
- read_unlock(&bond->curr_slave_lock);
} else {
bond_for_each_slave(bond, slave) {
dev_uc_sync_multiple(slave->dev, bond_dev);
dev_mc_sync_multiple(slave->dev, bond_dev);
}
}
-
- read_unlock(&bond->lock);
}
static int bond_neigh_init(struct neighbour *n)
--
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