bonding: 3ad: convert to bond->mode_lock

Now that we have bond->mode_lock, we can remove the state_machine_lock
and use it in its place. There're no fast paths requiring the per-port
spinlocks so it should be okay to consolidate them into mode_lock.
Also move it inside the unbinding function as we don't want to expose
mode_lock outside of the specific modes.

Suggested-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 21 insertions, 49 deletions

diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c
index 1824d1df4d09..2bb360f32a64 100644
--- a/drivers/net/bonding/bond_3ad.c
+++ b/drivers/net/bonding/bond_3ad.c
@@ -234,24 +234,6 @@ static inline int __check_agg_selection_timer(struct port *port)
 }
 
 /**
- * __get_state_machine_lock - lock the port's state machines
- * @port: the port we're looking at
- */
-static inline void __get_state_machine_lock(struct port *port)
-{
-        spin_lock_bh(&(SLAVE_AD_INFO(port->slave)->state_machine_lock));
-}
-
-/**
- * __release_state_machine_lock - unlock the port's state machines
- * @port: the port we're looking at
- */
-static inline void __release_state_machine_lock(struct port *port)
-{
-        spin_unlock_bh(&(SLAVE_AD_INFO(port->slave)->state_machine_lock));
-}
-
-/**
  * __get_link_speed - get a port's speed
  * @port: the port we're looking at
  *
@@ -341,16 +323,6 @@ static u8 __get_duplex(struct port *port)
         return retval;
 }
 
-/**
- * __initialize_port_locks - initialize a port's STATE machine spinlock
- * @port: the slave of the port we're looking at
- */
-static inline void __initialize_port_locks(struct slave *slave)
-{
-        /* make sure it isn't called twice */
-        spin_lock_init(&(SLAVE_AD_INFO(slave)->state_machine_lock));
-}
-
 /* Conversions */
 
 /**
@@ -1843,7 +1815,6 @@ void bond_3ad_bind_slave(struct slave *slave)
 
                 ad_initialize_port(port, bond->params.lacp_fast);
 
-                __initialize_port_locks(slave);
                 port->slave = slave;
                 port->actor_port_number = SLAVE_AD_INFO(slave)->id;
                 /* key is determined according to the link speed, duplex and user key(which
@@ -1899,6 +1870,8 @@ void bond_3ad_unbind_slave(struct slave *slave)
         struct slave *slave_iter;
         struct list_head *iter;
 
+        /* Sync against bond_3ad_state_machine_handler() */
+        spin_lock_bh(&bond->mode_lock);
         aggregator = &(SLAVE_AD_INFO(slave)->aggregator);
         port = &(SLAVE_AD_INFO(slave)->port);
 
@@ -1906,7 +1879,7 @@ void bond_3ad_unbind_slave(struct slave *slave)
         if (!port->slave) {
                 netdev_warn(bond->dev, "Trying to unbind an uninitialized port on %s\n",
                             slave->dev->name);
-                return;
+                goto out;
         }
 
         netdev_dbg(bond->dev, "Unbinding Link Aggregation Group %d\n",
@@ -2032,6 +2005,9 @@ void bond_3ad_unbind_slave(struct slave *slave)
                 }
         }
         port->slave = NULL;
+
+out:
+        spin_unlock_bh(&bond->mode_lock);
 }
 
 /**
@@ -2057,6 +2033,10 @@ void bond_3ad_state_machine_handler(struct work_struct *work)
         struct port *port;
         bool should_notify_rtnl = BOND_SLAVE_NOTIFY_LATER;
 
+        /* Lock to protect data accessed by all (e.g., port->sm_vars) and
+         * against running with bond_3ad_unbind_slave. ad_rx_machine may run
+         * concurrently due to incoming LACPDU as well.
+         */
         spin_lock_bh(&bond->mode_lock);
         rcu_read_lock();
 
@@ -2093,12 +2073,6 @@ void bond_3ad_state_machine_handler(struct work_struct *work)
                         goto re_arm;
                 }
 
-                /* Lock around state machines to protect data accessed
-                 * by all (e.g., port->sm_vars).  ad_rx_machine may run
-                 * concurrently due to incoming LACPDU.
-                 */
-                __get_state_machine_lock(port);
-
                 ad_rx_machine(NULL, port);
                 ad_periodic_machine(port);
                 ad_port_selection_logic(port);
@@ -2108,8 +2082,6 @@ void bond_3ad_state_machine_handler(struct work_struct *work)
                 /* turn off the BEGIN bit, since we already handled it */
                 if (port->sm_vars & AD_PORT_BEGIN)
                         port->sm_vars &= ~AD_PORT_BEGIN;
-
-                __release_state_machine_lock(port);
         }
 
 re_arm:
@@ -2161,9 +2133,9 @@ static int bond_3ad_rx_indication(struct lacpdu *lacpdu, struct slave *slave,
                         netdev_dbg(slave->bond->dev, "Received LACPDU on port %d\n",
                                    port->actor_port_number);
                         /* Protect against concurrent state machines */
-                        __get_state_machine_lock(port);
+                        spin_lock(&slave->bond->mode_lock);
                         ad_rx_machine(lacpdu, port);
-                        __release_state_machine_lock(port);
+                        spin_unlock(&slave->bond->mode_lock);
                         break;
 
                 case AD_TYPE_MARKER:
@@ -2213,7 +2185,7 @@ void bond_3ad_adapter_speed_changed(struct slave *slave)
                 return;
         }
 
-        __get_state_machine_lock(port);
+        spin_lock_bh(&slave->bond->mode_lock);
 
         port->actor_admin_port_key &= ~AD_SPEED_KEY_BITS;
         port->actor_oper_port_key = port->actor_admin_port_key |=
@@ -2224,7 +2196,7 @@ void bond_3ad_adapter_speed_changed(struct slave *slave)
          */
         port->sm_vars |= AD_PORT_BEGIN;
 
-        __release_state_machine_lock(port);
+        spin_unlock_bh(&slave->bond->mode_lock);
 }
 
 /**
@@ -2246,7 +2218,7 @@ void bond_3ad_adapter_duplex_changed(struct slave *slave)
                 return;
         }
 
-        __get_state_machine_lock(port);
+        spin_lock_bh(&slave->bond->mode_lock);
 
         port->actor_admin_port_key &= ~AD_DUPLEX_KEY_BITS;
         port->actor_oper_port_key = port->actor_admin_port_key |=
@@ -2257,7 +2229,7 @@ void bond_3ad_adapter_duplex_changed(struct slave *slave)
          */
         port->sm_vars |= AD_PORT_BEGIN;
 
-        __release_state_machine_lock(port);
+        spin_unlock_bh(&slave->bond->mode_lock);
 }
 
 /**
@@ -2280,7 +2252,7 @@ void bond_3ad_handle_link_change(struct slave *slave, char link)
                 return;
         }
 
-        __get_state_machine_lock(port);
+        spin_lock_bh(&slave->bond->mode_lock);
         /* on link down we are zeroing duplex and speed since
          * some of the adaptors(ce1000.lan) report full duplex/speed
          * instead of N/A(duplex) / 0(speed).
@@ -2311,7 +2283,7 @@ void bond_3ad_handle_link_change(struct slave *slave, char link)
          */
         port->sm_vars |= AD_PORT_BEGIN;
 
-        __release_state_machine_lock(port);
+        spin_unlock_bh(&slave->bond->mode_lock);
 }
 
 /**
@@ -2495,7 +2467,7 @@ int bond_3ad_lacpdu_recv(const struct sk_buff *skb, struct bonding *bond,
  * When modify lacp_rate parameter via sysfs,
  * update actor_oper_port_state of each port.
  *
- * Hold slave->state_machine_lock,
+ * Hold bond->mode_lock,
  * so we can modify port->actor_oper_port_state,
  * no matter bond is up or down.
  */
@@ -2507,13 +2479,13 @@ void bond_3ad_update_lacp_rate(struct bonding *bond)
         int lacp_fast;
 
         lacp_fast = bond->params.lacp_fast;
+        spin_lock_bh(&bond->mode_lock);
         bond_for_each_slave(bond, slave, iter) {
                 port = &(SLAVE_AD_INFO(slave)->port);
-                __get_state_machine_lock(port);
                 if (lacp_fast)
                         port->actor_oper_port_state |= AD_STATE_LACP_TIMEOUT;
                 else
                         port->actor_oper_port_state &= ~AD_STATE_LACP_TIMEOUT;
-                __release_state_machine_lock(port);
         }
+        spin_unlock_bh(&bond->mode_lock);
 }