From 52fbb2907988aa0583c6d9d53a56aee090b2df7e Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 9 Jun 2016 07:45:11 -0700 Subject: [PATCH 1/5] net: sched: fix qdisc->running lockdep annotations 1) qdisc_run_begin() is really using the equivalent of a trylock. Instead of using write_seqcount_begin(), use a combination of raw_write_seqcount_begin() and correct lockdep annotation. 2) sch_direct_xmit() should use regular spin_lock(root_lock) Fixes: f9eb8aea2a1e ("net_sched: transform qdisc running bit into a seqcount") Signed-off-by: Eric Dumazet Reported-by: David Ahern Signed-off-by: David S. Miller --- include/net/sch_generic.h | 6 +++++- net/sched/sch_generic.c | 4 ++-- 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index 49534e28824be..a4c0f1649e2b0 100644 --- 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/sched/sch_generic.c b/net/sched/sch_generic.c index cebea73e70ac0..cad810b45e31c 100644 --- 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 */ From d3fff6c443fe8f8a5ef2bdcea45e2ff39db948c7 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 9 Jun 2016 07:45:12 -0700 Subject: [PATCH 2/5] net: add netdev_lockdep_set_classes() helper It is time to add netdev_lockdep_set_classes() helper so that lockdep annotations per device type are easier to manage. This removes a lot of copies and missing annotations. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- drivers/net/bonding/bond_main.c | 24 +----------------------- drivers/net/ppp/ppp_generic.c | 6 +----- drivers/net/team/team.c | 21 +-------------------- include/linux/netdevice.h | 17 +++++++++++++++++ net/bluetooth/6lowpan.c | 15 +-------------- net/ieee802154/6lowpan/core.c | 16 +--------------- net/l2tp/l2tp_eth.c | 6 +----- 7 files changed, 23 insertions(+), 82 deletions(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 681af31a60ed5..90157e20357e6 100644 --- 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/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index aeabaa42317f0..17953ab15000d 100644 --- 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 00eb38956a2c5..0a1bb8387d96d 100644 --- 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/include/linux/netdevice.h b/include/linux/netdevice.h index 541562333ba5d..4f234b1028926 100644 --- 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/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c index 977a11e418d08..d020299baba41 100644 --- 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 14aa5effd29a5..4e2b30894224c 100644 --- 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 c00d72d182fa7..57fc5a46ce061 100644 --- 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; } From 78e7a2ae872770e5f26bf794b97b7b8e3e30ccfd Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 9 Jun 2016 07:45:13 -0700 Subject: [PATCH 3/5] net: vrf: call netdev_lockdep_set_classes() In case a qdisc is used on a vrf device, we need to use different lockdep classes to avoid false positives. Use the new netdev_lockdep_set_classes() generic helper. Reported-by: David Ahern Signed-off-by: Eric Dumazet Tested-by: David Ahern Signed-off-by: David S. Miller --- drivers/net/vrf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c index e3e693bf0dec3..b82e3527924e6 100644 --- 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: From 24ffd752007fb04e8efb560029c6076f6f3c0c5e Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 9 Jun 2016 07:45:14 -0700 Subject: [PATCH 4/5] net: macvlan: call netdev_lockdep_set_classes() In case a qdisc is used on a macvlan device, we need to use different lockdep classes to avoid false positives. Use the new netdev_lockdep_set_classes() generic helper. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- drivers/net/macvlan.c | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index 0c65bd914aeda..cd9b53834bf60 100644 --- 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) From 0d7dd798fd89d986a6c59030b704827a4e6a13b4 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 9 Jun 2016 07:45:15 -0700 Subject: [PATCH 5/5] net: ipvlan: call netdev_lockdep_set_classes() In case a qdisc is used on a ipvlan device, we need to use different lockdep classes to avoid false positives. Use the new netdev_lockdep_set_classes() generic helper. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- drivers/net/ipvlan/ipvlan_main.c | 22 +--------------------- 1 file changed, 1 insertion(+), 21 deletions(-) diff --git a/drivers/net/ipvlan/ipvlan_main.c b/drivers/net/ipvlan/ipvlan_main.c index 1c4d395fbd494..18b4e8c7f68aa 100644 --- 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)