* [PATCH v3 net-next 1/5] net: sched: fix qdisc->running lockdep annotations
2016-06-09 14:45 [PATCH v3 net-next 0/5] net: better lockdep annotations Eric Dumazet
@ 2016-06-09 14:45 ` Eric Dumazet
2016-06-09 14:45 ` [PATCH v3 net-next 2/5] net: add netdev_lockdep_set_classes() helper Eric Dumazet
` (4 subsequent siblings)
5 siblings, 0 replies; 8+ messages in thread
From: Eric Dumazet @ 2016-06-09 14:45 UTC (permalink / raw)
To: David S . Miller; +Cc: netdev, Eric Dumazet, David Ahern, Eric Dumazet
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 <edumazet@google.com>
Reported-by: David Ahern <dsa@cumulusnetworks.com>
---
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 c4f5749342ec..d53ecfc1d60e 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -104,7 +104,11 @@ 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 cebea73e70ac..cad810b45e31 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 */
--
2.8.0.rc3.226.g39d4020
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v3 net-next 2/5] net: add netdev_lockdep_set_classes() helper
2016-06-09 14:45 [PATCH v3 net-next 0/5] net: better lockdep annotations Eric Dumazet
2016-06-09 14:45 ` [PATCH v3 net-next 1/5] net: sched: fix qdisc->running " Eric Dumazet
@ 2016-06-09 14:45 ` Eric Dumazet
2016-06-09 14:45 ` [PATCH v3 net-next 3/5] net: vrf: call netdev_lockdep_set_classes() Eric Dumazet
` (3 subsequent siblings)
5 siblings, 0 replies; 8+ messages in thread
From: Eric Dumazet @ 2016-06-09 14:45 UTC (permalink / raw)
To: David S . Miller; +Cc: netdev, Eric Dumazet, David Ahern, Eric Dumazet
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 <edumazet@google.com>
---
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 681af31a60ed..90157e20357e 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 aeabaa42317f..17953ab15000 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 00eb38956a2c..0a1bb8387d96 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 541562333ba5..4f234b102892 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 977a11e418d0..d020299baba4 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 14aa5effd29a..4e2b30894224 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 c00d72d182fa..57fc5a46ce06 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;
}
--
2.8.0.rc3.226.g39d4020
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v3 net-next 3/5] net: vrf: call netdev_lockdep_set_classes()
2016-06-09 14:45 [PATCH v3 net-next 0/5] net: better lockdep annotations Eric Dumazet
2016-06-09 14:45 ` [PATCH v3 net-next 1/5] net: sched: fix qdisc->running " Eric Dumazet
2016-06-09 14:45 ` [PATCH v3 net-next 2/5] net: add netdev_lockdep_set_classes() helper Eric Dumazet
@ 2016-06-09 14:45 ` Eric Dumazet
2016-06-09 15:05 ` David Ahern
2016-06-09 14:45 ` [PATCH v3 net-next 4/5] net: macvlan: " Eric Dumazet
` (2 subsequent siblings)
5 siblings, 1 reply; 8+ messages in thread
From: Eric Dumazet @ 2016-06-09 14:45 UTC (permalink / raw)
To: David S . Miller; +Cc: netdev, Eric Dumazet, David Ahern, Eric Dumazet
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 <dsa@cumulusnetworks.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
---
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 e3e693bf0dec..b82e3527924e 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:
--
2.8.0.rc3.226.g39d4020
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH v3 net-next 3/5] net: vrf: call netdev_lockdep_set_classes()
2016-06-09 14:45 ` [PATCH v3 net-next 3/5] net: vrf: call netdev_lockdep_set_classes() Eric Dumazet
@ 2016-06-09 15:05 ` David Ahern
0 siblings, 0 replies; 8+ messages in thread
From: David Ahern @ 2016-06-09 15:05 UTC (permalink / raw)
To: Eric Dumazet, David S . Miller; +Cc: netdev, Eric Dumazet
On 6/9/16 8:45 AM, Eric Dumazet wrote:
> 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 <dsa@cumulusnetworks.com>
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> ---
> 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 e3e693bf0dec..b82e3527924e 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:
>
Works for me. Thanks, Eric.
Tested-by: David Ahern <dsa@cumulusnetworks.com>
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v3 net-next 4/5] net: macvlan: call netdev_lockdep_set_classes()
2016-06-09 14:45 [PATCH v3 net-next 0/5] net: better lockdep annotations Eric Dumazet
` (2 preceding siblings ...)
2016-06-09 14:45 ` [PATCH v3 net-next 3/5] net: vrf: call netdev_lockdep_set_classes() Eric Dumazet
@ 2016-06-09 14:45 ` Eric Dumazet
2016-06-09 14:45 ` [PATCH v3 net-next 5/5] net: ipvlan: " Eric Dumazet
2016-06-09 20:29 ` [PATCH v3 net-next 0/5] net: better lockdep annotations David Miller
5 siblings, 0 replies; 8+ messages in thread
From: Eric Dumazet @ 2016-06-09 14:45 UTC (permalink / raw)
To: David S . Miller; +Cc: netdev, Eric Dumazet, David Ahern, Eric Dumazet
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 <edumazet@google.com>
---
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 0c65bd914aed..cd9b53834bf6 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)
--
2.8.0.rc3.226.g39d4020
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v3 net-next 5/5] net: ipvlan: call netdev_lockdep_set_classes()
2016-06-09 14:45 [PATCH v3 net-next 0/5] net: better lockdep annotations Eric Dumazet
` (3 preceding siblings ...)
2016-06-09 14:45 ` [PATCH v3 net-next 4/5] net: macvlan: " Eric Dumazet
@ 2016-06-09 14:45 ` Eric Dumazet
2016-06-09 20:29 ` [PATCH v3 net-next 0/5] net: better lockdep annotations David Miller
5 siblings, 0 replies; 8+ messages in thread
From: Eric Dumazet @ 2016-06-09 14:45 UTC (permalink / raw)
To: David S . Miller; +Cc: netdev, Eric Dumazet, David Ahern, Eric Dumazet
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 <edumazet@google.com>
---
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 1c4d395fbd49..18b4e8c7f68a 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)
--
2.8.0.rc3.226.g39d4020
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH v3 net-next 0/5] net: better lockdep annotations
2016-06-09 14:45 [PATCH v3 net-next 0/5] net: better lockdep annotations Eric Dumazet
` (4 preceding siblings ...)
2016-06-09 14:45 ` [PATCH v3 net-next 5/5] net: ipvlan: " Eric Dumazet
@ 2016-06-09 20:29 ` David Miller
5 siblings, 0 replies; 8+ messages in thread
From: David Miller @ 2016-06-09 20:29 UTC (permalink / raw)
To: edumazet; +Cc: netdev, dsa, eric.dumazet
From: Eric Dumazet <edumazet@google.com>
Date: Thu, 9 Jun 2016 07:45:10 -0700
> 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 :)
Indeed :)
Applied, thanks Eric.
^ permalink raw reply [flat|nested] 8+ messages in thread