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: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>

diff --git a/net/batman-adv/bat_v.c b/net/batman-adv/bat_v.c
index 64054edc2e3ca3539cac9baf54bab95cdce53629..4ff6cf1ecae70d0a89677b21165ded2fc005e9af 100644 (file)
--- a/net/batman-adv/bat_v.c
+++ b/net/batman-adv/bat_v.c
@@ -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);
 }

diff --git a/net/batman-adv/bat_v_ogm.c b/net/batman-adv/bat_v_ogm.c
index 76b732e2f31c6f9622661e36df56752e494f00f8..714ce56cfcc827488551a06736b699a040b559c6 100644 (file)
--- a/net/batman-adv/bat_v_ogm.c
+++ b/net/batman-adv/bat_v_ogm.c
@@ -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);
 }
 
 /**

diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index 4d7f1baee7b7da7d32060014400e89db9c7f0b7a..47718a82eaf2f20aac55f4657eefe7cdfb3e7264 100644 (file)
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -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