diff options
| -rw-r--r-- | include/net/tc_act/tc_mirred.h | 2 | ||||
| -rw-r--r-- | net/sched/act_mirred.c | 57 |
2 files changed, 31 insertions, 28 deletions
diff --git a/include/net/tc_act/tc_mirred.h b/include/net/tc_act/tc_mirred.h index 4dd77a1c106b..dae96bae1c19 100644 --- a/include/net/tc_act/tc_mirred.h +++ b/include/net/tc_act/tc_mirred.h @@ -8,7 +8,7 @@ struct tcf_mirred { int tcfm_eaction; int tcfm_ifindex; int tcfm_ok_push; - struct net_device *tcfm_dev; + struct net_device __rcu *tcfm_dev; struct list_head tcfm_list; }; #define to_mirred(a) \ diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c index 002cd6c83dc6..19cd8904efa0 100644 --- a/net/sched/act_mirred.c +++ b/net/sched/act_mirred.c @@ -35,9 +35,11 @@ static LIST_HEAD(mirred_list); static void tcf_mirred_release(struct tc_action *a, int bind) { struct tcf_mirred *m = to_mirred(a); + struct net_device *dev = rcu_dereference_protected(m->tcfm_dev, 1); + list_del(&m->tcfm_list); - if (m->tcfm_dev) - dev_put(m->tcfm_dev); + if (dev) + dev_put(dev); } static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = { @@ -94,7 +96,7 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla, if (dev == NULL) return -EINVAL; ret = tcf_hash_create(parm->index, est, a, sizeof(*m), - bind, false); + bind, true); if (ret) return ret; ret = ACT_P_CREATED; @@ -106,18 +108,18 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla, } m = to_mirred(a); - spin_lock_bh(&m->tcf_lock); + ASSERT_RTNL(); m->tcf_action = parm->action; m->tcfm_eaction = parm->eaction; if (dev != NULL) { m->tcfm_ifindex = parm->ifindex; if (ret != ACT_P_CREATED) - dev_put(m->tcfm_dev); + dev_put(rcu_dereference_protected(m->tcfm_dev, 1)); dev_hold(dev); - m->tcfm_dev = dev; + rcu_assign_pointer(m->tcfm_dev, dev); m->tcfm_ok_push = ok_push; } - spin_unlock_bh(&m->tcf_lock); + if (ret == ACT_P_CREATED) { list_add(&m->tcfm_list, &mirred_list); tcf_hash_insert(a); @@ -132,20 +134,22 @@ static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a, struct tcf_mirred *m = a->priv; struct net_device *dev; struct sk_buff *skb2; + int retval, err; u32 at; - int retval, err = 1; - spin_lock(&m->tcf_lock); - m->tcf_tm.lastuse = jiffies; - bstats_update(&m->tcf_bstats, skb); + tcf_lastuse_update(&m->tcf_tm); + + bstats_cpu_update(this_cpu_ptr(m->common.cpu_bstats), skb); - dev = m->tcfm_dev; - if (!dev) { - printk_once(KERN_NOTICE "tc mirred: target device is gone\n"); + rcu_read_lock(); + retval = READ_ONCE(m->tcf_action); + dev = rcu_dereference(m->tcfm_dev); + if (unlikely(!dev)) { + pr_notice_once("tc mirred: target device is gone\n"); goto out; } - if (!(dev->flags & IFF_UP)) { + if (unlikely(!(dev->flags & IFF_UP))) { net_notice_ratelimited("tc mirred to Houston: device %s is down\n", dev->name); goto out; @@ -153,7 +157,7 @@ static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a, at = G_TC_AT(skb->tc_verd); skb2 = skb_clone(skb, GFP_ATOMIC); - if (skb2 == NULL) + if (!skb2) goto out; if (!(at & AT_EGRESS)) { @@ -169,16 +173,13 @@ static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a, skb2->dev = dev; err = dev_queue_xmit(skb2); -out: if (err) { - m->tcf_qstats.overlimits++; +out: + qstats_overlimit_inc(this_cpu_ptr(m->common.cpu_qstats)); if (m->tcfm_eaction != TCA_EGRESS_MIRROR) retval = TC_ACT_SHOT; - else - retval = m->tcf_action; - } else - retval = m->tcf_action; - spin_unlock(&m->tcf_lock); + } + rcu_read_unlock(); return retval; } @@ -217,14 +218,16 @@ static int mirred_device_event(struct notifier_block *unused, struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct tcf_mirred *m; + ASSERT_RTNL(); if (event == NETDEV_UNREGISTER) list_for_each_entry(m, &mirred_list, tcfm_list) { - spin_lock_bh(&m->tcf_lock); - if (m->tcfm_dev == dev) { + if (rcu_access_pointer(m->tcfm_dev) == dev) { dev_put(dev); - m->tcfm_dev = NULL; + /* Note : no rcu grace period necessary, as + * net_device are already rcu protected. + */ + RCU_INIT_POINTER(m->tcfm_dev, NULL); } - spin_unlock_bh(&m->tcf_lock); } return NOTIFY_DONE; |