Commit 2afe02ee authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'bonding_rcu' 

Veaceslav Falico says:

====================
bonding: fix bond_3ad RCU usage

While digging through bond_3ad.c I've found that the RCU usage there is
just wrong - it's used as a kind of mutex/spinlock instead of RCU.

v3->v4: remove useless goto and wrap __get_first_agg() in proper RCU.

v2->v3: make bond_3ad_set_carrier() use RCU read lock for the whole
function, so that all other functions will be protected by RCU as well.
This way we can use _rcu variants everywhere.

v1->v2: use generic primitives instead of _rcu ones cause we can hold RTNL
lock without RCU one, which is still safe.

This patchset is on top of bond_3ad.c cleanup:
http://www.spinics.net/lists/netdev/msg265447.html


====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents 853dc21b 49b7624e

drivers/net/bonding/bond_3ad.c

+19 −18
Original line number Diff line number Diff line
@@ -143,11 +143,13 @@ static inline struct bonding *__get_bond_by_port(struct port *port) 
 *

 * Return the aggregator of the first slave in @bond, or %NULL if it can't be

 * found.

 * The caller must hold RCU or RTNL lock.

 */

static inline struct aggregator *__get_first_agg(struct port *port)

{

	struct bonding *bond = __get_bond_by_port(port);

	struct slave *first_slave;

	struct aggregator *agg;



	/* If there's no bond for this port, or bond has no slaves */

	if (bond == NULL)
@@ -155,9 +157,10 @@ static inline struct aggregator *__get_first_agg(struct port *port) 


	rcu_read_lock();

	first_slave = bond_first_slave_rcu(bond);

	agg = first_slave ? &(SLAVE_AD_INFO(first_slave).aggregator) : NULL;

	rcu_read_unlock();



	return first_slave ? &(SLAVE_AD_INFO(first_slave).aggregator) : NULL;

	return agg;

}



/**
@@ -675,6 +678,8 @@ static u32 __get_agg_bandwidth(struct aggregator *aggregator) 
/**

 * __get_active_agg - get the current active aggregator

 * @aggregator: the aggregator we're looking at

 *

 * Caller must hold RCU lock.

 */

static struct aggregator *__get_active_agg(struct aggregator *aggregator)

{
@@ -682,13 +687,9 @@ static struct aggregator *__get_active_agg(struct aggregator *aggregator) 
	struct list_head *iter;

	struct slave *slave;



	rcu_read_lock();

	bond_for_each_slave_rcu(bond, slave, iter)

		if (SLAVE_AD_INFO(slave).aggregator.is_active) {

			rcu_read_unlock();

		if (SLAVE_AD_INFO(slave).aggregator.is_active)

			return &(SLAVE_AD_INFO(slave).aggregator);

		}

	rcu_read_unlock();



	return NULL;

}
@@ -1496,11 +1497,11 @@ static void ad_agg_selection_logic(struct aggregator *agg) 
	struct slave *slave;

	struct port *port;



	rcu_read_lock();

	origin = agg;

	active = __get_active_agg(agg);

	best = (active && agg_device_up(active)) ? active : NULL;



	rcu_read_lock();

	bond_for_each_slave_rcu(bond, slave, iter) {

		agg = &(SLAVE_AD_INFO(slave).aggregator);
@@ -2327,32 +2328,32 @@ int bond_3ad_set_carrier(struct bonding *bond) 
{

	struct aggregator *active;

	struct slave *first_slave;

	int ret = 1;



	rcu_read_lock();

	first_slave = bond_first_slave_rcu(bond);

	rcu_read_unlock();

	if (!first_slave)

		return 0;

	if (!first_slave) {

		ret = 0;

		goto out;

	}

	active = __get_active_agg(&(SLAVE_AD_INFO(first_slave).aggregator));

	if (active) {

		/* are enough slaves available to consider link up? */

		if (active->num_of_ports < bond->params.min_links) {

			if (netif_carrier_ok(bond->dev)) {

				netif_carrier_off(bond->dev);

				return 1;

				goto out;

			}

		} else if (!netif_carrier_ok(bond->dev)) {

			netif_carrier_on(bond->dev);

			return 1;

		}

		return 0;

			goto out;

		}



	if (netif_carrier_ok(bond->dev)) {

	} else if (netif_carrier_ok(bond->dev)) {

		netif_carrier_off(bond->dev);

		return 1;

	}

	return 0;

out:

	rcu_read_unlock();

	return ret;

}



/**

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