From 98b90f26651f9d84cfbb0221c9a3d9863c5bea69 Mon Sep 17 00:00:00 2001
From: Veaceslav Falico <vfalico@redhat.com>
Date: Mon, 27 Jan 2014 14:37:31 +0100
Subject: [PATCH] bonding: RCUify bond_ab_arp_probe
Currently bond_ab_arp_probe() is always called under rcu_read_lock(),
however to work with curr_active_slave we're still holding the
curr_slave_lock.
To remove that curr_slave_lock - rcu_dereference the bond's
curr_active_slave and use it further - so that we're sure the slave won't
go away, and we don't care if it will change in the meanwhile.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/net/bonding/bond_main.c | 16 ++++++----------
1 file changed, 6 insertions(+), 10 deletions(-)
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index a7db819bca92..27e6fddb2206 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -2605,25 +2605,21 @@ do_failover:
static void bond_ab_arp_probe(struct bonding *bond)
{
struct slave *slave, *before = NULL, *new_slave = NULL,
- *curr_arp_slave = rcu_dereference(bond->current_arp_slave);
+ *curr_arp_slave = rcu_dereference(bond->current_arp_slave),
+ *curr_active_slave = rcu_dereference(bond->curr_active_slave);
struct list_head *iter;
bool found = false;
- read_lock(&bond->curr_slave_lock);
-
- if (curr_arp_slave && bond->curr_active_slave)
+ if (curr_arp_slave && curr_active_slave)
pr_info("PROBE: c_arp %s && cas %s BAD\n",
curr_arp_slave->dev->name,
- bond->curr_active_slave->dev->name);
+ curr_active_slave->dev->name);
- if (bond->curr_active_slave) {
- bond_arp_send_all(bond, bond->curr_active_slave);
- read_unlock(&bond->curr_slave_lock);
+ if (curr_active_slave) {
+ bond_arp_send_all(bond, curr_active_slave);
return;
}
- read_unlock(&bond->curr_slave_lock);
-
/* if we don't have a curr_active_slave, search for the next available
* backup slave from the current_arp_slave and make it the candidate
* for becoming the curr_active_slave
--
2.20.1