Commit baa1e8a0 authored by Christophe JAILLET's avatar Christophe JAILLET Committed by Simon Wunderlich
Browse files

batman-adv: Axe 'aggr_list_lock' 



'aggr_list.lock' can safely be used in place of another explicit spinlock
when access to 'aggr_list' has to be guarded.

This avoids to take 2 locks, knowing that the 2nd one is always successful.

Now that the 'aggr_list.lock' is handled explicitly, the lock-free
__sbk_something() variants should be used when dealing with 'aggr_list'.

Signed-off-by: default avatarChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: default avatarSven Eckelmann <sven@narfation.org>
Signed-off-by: default avatarSimon Wunderlich <sw@simonwunderlich.de>
parent 9044854e

net/batman-adv/bat_v.c

+0 −1
Original line number Diff line number Diff line
@@ -1085,7 +1085,6 @@ void batadv_v_hardif_init(struct batadv_hard_iface *hard_iface) 


	hard_iface->bat_v.aggr_len = 0;

	skb_queue_head_init(&hard_iface->bat_v.aggr_list);

	spin_lock_init(&hard_iface->bat_v.aggr_list_lock);

	INIT_DELAYED_WORK(&hard_iface->bat_v.aggr_wq,

			  batadv_v_ogm_aggr_work);

}

net/batman-adv/bat_v_ogm.c

+15 −15
Original line number Diff line number Diff line
@@ -152,7 +152,7 @@ static unsigned int batadv_v_ogm_len(struct sk_buff *skb) 
 * @skb: the OGM to check

 * @hard_iface: the interface to use to send the OGM

 *

 * Caller needs to hold the hard_iface->bat_v.aggr_list_lock.

 * Caller needs to hold the hard_iface->bat_v.aggr_list.lock.

 *

 * Return: True, if the given OGMv2 packet still fits, false otherwise.

 */
@@ -163,7 +163,7 @@ static bool batadv_v_ogm_queue_left(struct sk_buff *skb, 
				 BATADV_MAX_AGGREGATION_BYTES);

	unsigned int ogm_len = batadv_v_ogm_len(skb);



	lockdep_assert_held(&hard_iface->bat_v.aggr_list_lock);

	lockdep_assert_held(&hard_iface->bat_v.aggr_list.lock);



	return hard_iface->bat_v.aggr_len + ogm_len <= max;

}
@@ -174,13 +174,13 @@ static bool batadv_v_ogm_queue_left(struct sk_buff *skb, 
 *

 * Empties the OGMv2 aggregation queue and frees all the skbs it contained.

 *

 * Caller needs to hold the hard_iface->bat_v.aggr_list_lock.

 * Caller needs to hold the hard_iface->bat_v.aggr_list.lock.

 */

static void batadv_v_ogm_aggr_list_free(struct batadv_hard_iface *hard_iface)

{

	lockdep_assert_held(&hard_iface->bat_v.aggr_list_lock);

	lockdep_assert_held(&hard_iface->bat_v.aggr_list.lock);



	skb_queue_purge(&hard_iface->bat_v.aggr_list);

	__skb_queue_purge(&hard_iface->bat_v.aggr_list);

	hard_iface->bat_v.aggr_len = 0;

}
@@ -193,7 +193,7 @@ static void batadv_v_ogm_aggr_list_free(struct batadv_hard_iface *hard_iface) 
 *

 * The aggregation queue is empty after this call.

 *

 * Caller needs to hold the hard_iface->bat_v.aggr_list_lock.

 * Caller needs to hold the hard_iface->bat_v.aggr_list.lock.

 */

static void batadv_v_ogm_aggr_send(struct batadv_hard_iface *hard_iface)

{
@@ -202,7 +202,7 @@ static void batadv_v_ogm_aggr_send(struct batadv_hard_iface *hard_iface) 
	unsigned int ogm_len;

	struct sk_buff *skb;



	lockdep_assert_held(&hard_iface->bat_v.aggr_list_lock);

	lockdep_assert_held(&hard_iface->bat_v.aggr_list.lock);



	if (!aggr_len)

		return;
@@ -216,7 +216,7 @@ static void batadv_v_ogm_aggr_send(struct batadv_hard_iface *hard_iface) 
	skb_reserve(skb_aggr, ETH_HLEN + NET_IP_ALIGN);

	skb_reset_network_header(skb_aggr);



	while ((skb = skb_dequeue(&hard_iface->bat_v.aggr_list))) {

	while ((skb = __skb_dequeue(&hard_iface->bat_v.aggr_list))) {

		hard_iface->bat_v.aggr_len -= batadv_v_ogm_len(skb);



		ogm_len = batadv_v_ogm_len(skb);
@@ -243,13 +243,13 @@ static void batadv_v_ogm_queue_on_if(struct sk_buff *skb, 
		return;

	}



	spin_lock_bh(&hard_iface->bat_v.aggr_list_lock);

	spin_lock_bh(&hard_iface->bat_v.aggr_list.lock);

	if (!batadv_v_ogm_queue_left(skb, hard_iface))

		batadv_v_ogm_aggr_send(hard_iface);



	hard_iface->bat_v.aggr_len += batadv_v_ogm_len(skb);

	skb_queue_tail(&hard_iface->bat_v.aggr_list, skb);

	spin_unlock_bh(&hard_iface->bat_v.aggr_list_lock);

	__skb_queue_tail(&hard_iface->bat_v.aggr_list, skb);

	spin_unlock_bh(&hard_iface->bat_v.aggr_list.lock);

}



/**
@@ -388,9 +388,9 @@ void batadv_v_ogm_aggr_work(struct work_struct *work) 
	batv = container_of(work, struct batadv_hard_iface_bat_v, aggr_wq.work);

	hard_iface = container_of(batv, struct batadv_hard_iface, bat_v);



	spin_lock_bh(&hard_iface->bat_v.aggr_list_lock);

	spin_lock_bh(&hard_iface->bat_v.aggr_list.lock);

	batadv_v_ogm_aggr_send(hard_iface);

	spin_unlock_bh(&hard_iface->bat_v.aggr_list_lock);

	spin_unlock_bh(&hard_iface->bat_v.aggr_list.lock);



	batadv_v_ogm_start_queue_timer(hard_iface);

}
@@ -421,9 +421,9 @@ void batadv_v_ogm_iface_disable(struct batadv_hard_iface *hard_iface) 
{

	cancel_delayed_work_sync(&hard_iface->bat_v.aggr_wq);



	spin_lock_bh(&hard_iface->bat_v.aggr_list_lock);

	spin_lock_bh(&hard_iface->bat_v.aggr_list.lock);

	batadv_v_ogm_aggr_list_free(hard_iface);

	spin_unlock_bh(&hard_iface->bat_v.aggr_list_lock);

	spin_unlock_bh(&hard_iface->bat_v.aggr_list.lock);

}



/**

net/batman-adv/types.h

+0 −3
Original line number Diff line number Diff line
@@ -130,9 +130,6 @@ struct batadv_hard_iface_bat_v { 
	/** @aggr_len: size of the OGM aggregate (excluding ethernet header) */

	unsigned int aggr_len;



	/** @aggr_list_lock: protects aggr_list */

	spinlock_t aggr_list_lock;



	/**

	 * @throughput_override: throughput override to disable link

	 *  auto-detection

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