Merge branch 'netdev_lockdep_set_classes'

Eric Dumazet says:

====================
net: better lockdep annotations

Introduction of qdisc->running seqcount added lockdep false positives.

While chasing the bug, it came to me that we had a lot of copies of the
same stuff in virtual drivers.

This patch series has the qdisc->running fix (considers that a trylock
is attempted in lockdep terminology), and adds a generic helper so
that we no longer have to patch many virtual drivers when a new per-device
or per-qdisc lock is added.

Thanks to David Ahern for reporting the issue and testing my patches :)
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 681af31a60ed5b0e789636a4e806f22eb684a7de..90157e20357e62f533f62887a3387bac63f088a6 100644 (file)
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -4607,28 +4607,6 @@ static int bond_check_params(struct bond_params *params)
        return 0;
 }
 
-static struct lock_class_key bonding_netdev_xmit_lock_key;
-static struct lock_class_key bonding_netdev_addr_lock_key;
-static struct lock_class_key bonding_tx_busylock_key;
-static struct lock_class_key bonding_qdisc_running_key;
-
-static void bond_set_lockdep_class_one(struct net_device *dev,
-                                      struct netdev_queue *txq,
-                                      void *_unused)
-{
-       lockdep_set_class(&txq->_xmit_lock,
-                         &bonding_netdev_xmit_lock_key);
-}
-
-static void bond_set_lockdep_class(struct net_device *dev)
-{
-       lockdep_set_class(&dev->addr_list_lock,
-                         &bonding_netdev_addr_lock_key);
-       netdev_for_each_tx_queue(dev, bond_set_lockdep_class_one, NULL);
-       dev->qdisc_tx_busylock = &bonding_tx_busylock_key;
-       dev->qdisc_running_key = &bonding_qdisc_running_key;
-}
-
 /* Called from registration process */
 static int bond_init(struct net_device *bond_dev)
 {
@@ -4641,7 +4619,7 @@ static int bond_init(struct net_device *bond_dev)
        if (!bond->wq)
                return -ENOMEM;
 
-       bond_set_lockdep_class(bond_dev);
+       netdev_lockdep_set_classes(bond_dev);
 
        list_add_tail(&bond->bond_list, &bn->dev_list);
 

diff --git a/drivers/net/ipvlan/ipvlan_main.c b/drivers/net/ipvlan/ipvlan_main.c
index 1c4d395fbd494cdc158427cb90f22820332421d7..18b4e8c7f68aa1824838f583f6d03fd19705f8a1 100644 (file)
--- a/drivers/net/ipvlan/ipvlan_main.c
+++ b/drivers/net/ipvlan/ipvlan_main.c
@@ -80,13 +80,6 @@ static void ipvlan_port_destroy(struct net_device *dev)
        kfree_rcu(port, rcu);
 }
 
-/* ipvlan network devices have devices nesting below it and are a special
- * "super class" of normal network devices; split their locks off into a
- * separate class since they always nest.
- */
-static struct lock_class_key ipvlan_netdev_xmit_lock_key;
-static struct lock_class_key ipvlan_netdev_addr_lock_key;
-
 #define IPVLAN_FEATURES \
        (NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
         NETIF_F_GSO | NETIF_F_TSO | NETIF_F_UFO | NETIF_F_GSO_ROBUST | \
@@ -96,19 +89,6 @@ static struct lock_class_key ipvlan_netdev_addr_lock_key;
 #define IPVLAN_STATE_MASK \
        ((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))
 
-static void ipvlan_set_lockdep_class_one(struct net_device *dev,
-                                        struct netdev_queue *txq,
-                                        void *_unused)
-{
-       lockdep_set_class(&txq->_xmit_lock, &ipvlan_netdev_xmit_lock_key);
-}
-
-static void ipvlan_set_lockdep_class(struct net_device *dev)
-{
-       lockdep_set_class(&dev->addr_list_lock, &ipvlan_netdev_addr_lock_key);
-       netdev_for_each_tx_queue(dev, ipvlan_set_lockdep_class_one, NULL);
-}
-
 static int ipvlan_init(struct net_device *dev)
 {
        struct ipvl_dev *ipvlan = netdev_priv(dev);
@@ -123,7 +103,7 @@ static int ipvlan_init(struct net_device *dev)
        dev->gso_max_segs = phy_dev->gso_max_segs;
        dev->hard_header_len = phy_dev->hard_header_len;
 
-       ipvlan_set_lockdep_class(dev);
+       netdev_lockdep_set_classes(dev);
 
        ipvlan->pcpu_stats = alloc_percpu(struct ipvl_pcpu_stats);
        if (!ipvlan->pcpu_stats)

diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index 0c65bd914aedaf6685925960801f9de3fed1a5cd..cd9b53834bf60a4345880b8c6b4b02967372dba6 100644 (file)
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -788,7 +788,6 @@ static int macvlan_change_mtu(struct net_device *dev, int new_mtu)
  * "super class" of normal network devices; split their locks off into a
  * separate class since they always nest.
  */
-static struct lock_class_key macvlan_netdev_xmit_lock_key;
 static struct lock_class_key macvlan_netdev_addr_lock_key;
 
 #define ALWAYS_ON_FEATURES \
@@ -809,20 +808,12 @@ static int macvlan_get_nest_level(struct net_device *dev)
        return ((struct macvlan_dev *)netdev_priv(dev))->nest_level;
 }
 
-static void macvlan_set_lockdep_class_one(struct net_device *dev,
-                                         struct netdev_queue *txq,
-                                         void *_unused)
-{
-       lockdep_set_class(&txq->_xmit_lock,
-                         &macvlan_netdev_xmit_lock_key);
-}
-
 static void macvlan_set_lockdep_class(struct net_device *dev)
 {
+       netdev_lockdep_set_classes(dev);
        lockdep_set_class_and_subclass(&dev->addr_list_lock,
                                       &macvlan_netdev_addr_lock_key,
                                       macvlan_get_nest_level(dev));
-       netdev_for_each_tx_queue(dev, macvlan_set_lockdep_class_one, NULL);
 }
 
 static int macvlan_init(struct net_device *dev)

diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c
index aeabaa42317f0d34174a40a42ac2664456c494c2..17953ab15000dbd5b118d43d34cd00f81163ba1b 100644 (file)
--- a/drivers/net/ppp/ppp_generic.c
+++ b/drivers/net/ppp/ppp_generic.c
@@ -1312,13 +1312,9 @@ ppp_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats64)
        return stats64;
 }
 
-static struct lock_class_key ppp_tx_busylock;
-static struct lock_class_key ppp_qdisc_running_key;
-
 static int ppp_dev_init(struct net_device *dev)
 {
-       dev->qdisc_tx_busylock = &ppp_tx_busylock;
-       dev->qdisc_running_key = &ppp_qdisc_running_key;
+       netdev_lockdep_set_classes(dev);
        return 0;
 }
 

diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c
index 00eb38956a2c53f44211800dc5769babc2be7ea6..0a1bb8387d96d3a337c0d0f91457130040b98441 100644 (file)
--- a/drivers/net/team/team.c
+++ b/drivers/net/team/team.c
@@ -1574,25 +1574,6 @@ static const struct team_option team_options[] = {
        },
 };
 
-static struct lock_class_key team_netdev_xmit_lock_key;
-static struct lock_class_key team_netdev_addr_lock_key;
-static struct lock_class_key team_tx_busylock_key;
-static struct lock_class_key team_qdisc_running_key;
-
-static void team_set_lockdep_class_one(struct net_device *dev,
-                                      struct netdev_queue *txq,
-                                      void *unused)
-{
-       lockdep_set_class(&txq->_xmit_lock, &team_netdev_xmit_lock_key);
-}
-
-static void team_set_lockdep_class(struct net_device *dev)
-{
-       lockdep_set_class(&dev->addr_list_lock, &team_netdev_addr_lock_key);
-       netdev_for_each_tx_queue(dev, team_set_lockdep_class_one, NULL);
-       dev->qdisc_tx_busylock = &team_tx_busylock_key;
-       dev->qdisc_running_key = &team_qdisc_running_key;
-}
 
 static int team_init(struct net_device *dev)
 {
@@ -1628,7 +1609,7 @@ static int team_init(struct net_device *dev)
                goto err_options_register;
        netif_carrier_off(dev);
 
-       team_set_lockdep_class(dev);
+       netdev_lockdep_set_classes(dev);
 
        return 0;
 

diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
index e3e693bf0dec344fd83469cf2ce04797c3bc3cee..b82e3527924e6a330953e462c075a09051b33a34 100644 (file)
--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -661,7 +661,7 @@ static int vrf_dev_init(struct net_device *dev)
 
        /* similarly, oper state is irrelevant; set to up to avoid confusion */
        dev->operstate = IF_OPER_UP;
-
+       netdev_lockdep_set_classes(dev);
        return 0;
 
 out_rth:

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 541562333ba5dd9184205364d378d0a72c6026f9..4f234b1028926a830ff5c6d883f003ebc1c4ae3f 100644 (file)
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1946,6 +1946,23 @@ static inline void netdev_for_each_tx_queue(struct net_device *dev,
                f(dev, &dev->_tx[i], arg);
 }
 
+#define netdev_lockdep_set_classes(dev)                                \
+{                                                              \
+       static struct lock_class_key qdisc_tx_busylock_key;     \
+       static struct lock_class_key qdisc_running_key;         \
+       static struct lock_class_key qdisc_xmit_lock_key;       \
+       static struct lock_class_key dev_addr_list_lock_key;    \
+       unsigned int i;                                         \
+                                                               \
+       (dev)->qdisc_tx_busylock = &qdisc_tx_busylock_key;      \
+       (dev)->qdisc_running_key = &qdisc_running_key;          \
+       lockdep_set_class(&(dev)->addr_list_lock,               \
+                         &dev_addr_list_lock_key);             \
+       for (i = 0; i < (dev)->num_tx_queues; i++)              \
+               lockdep_set_class(&(dev)->_tx[i]._xmit_lock,    \
+                                 &qdisc_xmit_lock_key);        \
+}
+
 struct netdev_queue *netdev_pick_tx(struct net_device *dev,
                                    struct sk_buff *skb,
                                    void *accel_priv);

diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 49534e28824be6a730db6f49121d543bfed65408..a4c0f1649e2b0edaade093f33c4debb55825494c 100644 (file)
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -97,7 +97,11 @@ static inline bool qdisc_run_begin(struct Qdisc *qdisc)
 {
        if (qdisc_is_running(qdisc))
                return false;
-       write_seqcount_begin(&qdisc->running);
+       /* Variant of write_seqcount_begin() telling lockdep a trylock
+        * was attempted.
+        */
+       raw_write_seqcount_begin(&qdisc->running);
+       seqcount_acquire(&qdisc->running.dep_map, 0, 1, _RET_IP_);
        return true;
 }
 

diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
index 977a11e418d089a17ffbf712103de2ac250fbef1..d020299baba41253022ca277711801bc9732828c 100644 (file)
--- a/net/bluetooth/6lowpan.c
+++ b/net/bluetooth/6lowpan.c
@@ -627,22 +627,9 @@ static netdev_tx_t bt_xmit(struct sk_buff *skb, struct net_device *netdev)
        return err < 0 ? NET_XMIT_DROP : err;
 }
 
-static struct lock_class_key bt_tx_busylock;
-static struct lock_class_key bt_netdev_xmit_lock_key;
-static struct lock_class_key bt_qdisc_running_key;
-
-static void bt_set_lockdep_class_one(struct net_device *dev,
-                                    struct netdev_queue *txq,
-                                    void *_unused)
-{
-       lockdep_set_class(&txq->_xmit_lock, &bt_netdev_xmit_lock_key);
-}
-
 static int bt_dev_init(struct net_device *dev)
 {
-       netdev_for_each_tx_queue(dev, bt_set_lockdep_class_one, NULL);
-       dev->qdisc_tx_busylock = &bt_tx_busylock;
-       dev->qdisc_running_key = &bt_qdisc_running_key;
+       netdev_lockdep_set_classes(dev);
 
        return 0;
 }

diff --git a/net/ieee802154/6lowpan/core.c b/net/ieee802154/6lowpan/core.c
index 14aa5effd29a545a23c33abbb25b9b3ba77ff22d..4e2b30894224ccda6701f2dadf7c062acbb1393e 100644 (file)
--- a/net/ieee802154/6lowpan/core.c
+++ b/net/ieee802154/6lowpan/core.c
@@ -58,23 +58,9 @@ static struct header_ops lowpan_header_ops = {
        .create = lowpan_header_create,
 };
 
-static struct lock_class_key lowpan_tx_busylock;
-static struct lock_class_key lowpan_netdev_xmit_lock_key;
-static struct lock_class_key lowpan_qdisc_running_key;
-
-static void lowpan_set_lockdep_class_one(struct net_device *ldev,
-                                        struct netdev_queue *txq,
-                                        void *_unused)
-{
-       lockdep_set_class(&txq->_xmit_lock,
-                         &lowpan_netdev_xmit_lock_key);
-}
-
 static int lowpan_dev_init(struct net_device *ldev)
 {
-       netdev_for_each_tx_queue(ldev, lowpan_set_lockdep_class_one, NULL);
-       ldev->qdisc_tx_busylock = &lowpan_tx_busylock;
-       ldev->qdisc_running_key = &lowpan_qdisc_running_key;
+       netdev_lockdep_set_classes(ldev);
 
        return 0;
 }

diff --git a/net/l2tp/l2tp_eth.c b/net/l2tp/l2tp_eth.c
index c00d72d182fa7be85759fce3ac88874b3cbb04af..57fc5a46ce06198c69efbdbbf78130cfb0724382 100644 (file)
--- a/net/l2tp/l2tp_eth.c
+++ b/net/l2tp/l2tp_eth.c
@@ -67,9 +67,6 @@ static inline struct l2tp_eth_net *l2tp_eth_pernet(struct net *net)
        return net_generic(net, l2tp_eth_net_id);
 }
 
-static struct lock_class_key l2tp_eth_tx_busylock;
-static struct lock_class_key l2tp_qdisc_running_key;
-
 static int l2tp_eth_dev_init(struct net_device *dev)
 {
        struct l2tp_eth *priv = netdev_priv(dev);
@@ -77,8 +74,7 @@ static int l2tp_eth_dev_init(struct net_device *dev)
        priv->dev = dev;
        eth_hw_addr_random(dev);
        eth_broadcast_addr(dev->broadcast);
-       dev->qdisc_tx_busylock = &l2tp_eth_tx_busylock;
-       dev->qdisc_running_key = &l2tp_qdisc_running_key;
+       netdev_lockdep_set_classes(dev);
 
        return 0;
 }

diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index cebea73e70ac00bd128630d2af37ae04eee5ee85..cad810b45e31c47f2c01cb020be914fafbf05638 100644 (file)
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -137,10 +137,10 @@ int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
 
                HARD_TX_UNLOCK(dev, txq);
        } else {
-               spin_lock_nested(root_lock, SINGLE_DEPTH_NESTING);
+               spin_lock(root_lock);
                return qdisc_qlen(q);
        }
-       spin_lock_nested(root_lock, SINGLE_DEPTH_NESTING);
+       spin_lock(root_lock);
 
        if (dev_xmit_complete(ret)) {
                /* Driver sent out skb successfully or skb was consumed */