diff options
| -rw-r--r-- | include/linux/rtnetlink.h | 5 | ||||
| -rw-r--r-- | include/net/pkt_sched.h | 1 | ||||
| -rw-r--r-- | include/net/sch_generic.h | 2 | ||||
| -rw-r--r-- | net/sched/sch_api.c | 18 | ||||
| -rw-r--r-- | net/sched/sch_generic.c | 25 |
5 files changed, 50 insertions, 1 deletions
diff --git a/include/linux/rtnetlink.h b/include/linux/rtnetlink.h index 9cdd76348d9a..bb9cb84114c1 100644 --- a/include/linux/rtnetlink.h +++ b/include/linux/rtnetlink.h @@ -85,6 +85,11 @@ static inline struct netdev_queue *dev_ingress_queue(struct net_device *dev) return rtnl_dereference(dev->ingress_queue); } +static inline struct netdev_queue *dev_ingress_queue_rcu(struct net_device *dev) +{ + return rcu_dereference(dev->ingress_queue); +} + struct netdev_queue *dev_ingress_queue_create(struct net_device *dev); #ifdef CONFIG_NET_INGRESS diff --git a/include/net/pkt_sched.h b/include/net/pkt_sched.h index 7dc769e5452b..a16fbe9a2a67 100644 --- a/include/net/pkt_sched.h +++ b/include/net/pkt_sched.h @@ -102,6 +102,7 @@ int qdisc_set_default(const char *id); void qdisc_hash_add(struct Qdisc *q, bool invisible); void qdisc_hash_del(struct Qdisc *q); struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle); +struct Qdisc *qdisc_lookup_rcu(struct net_device *dev, u32 handle); struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, struct nlattr *tab, struct netlink_ext_ack *extack); diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index fadb1a4d4ee8..091b40c198ff 100644 --- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -105,6 +105,7 @@ struct Qdisc { spinlock_t busylock ____cacheline_aligned_in_smp; spinlock_t seqlock; + struct rcu_head rcu; }; static inline void qdisc_refcount_inc(struct Qdisc *qdisc) @@ -555,6 +556,7 @@ struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue, struct Qdisc *qdisc); void qdisc_reset(struct Qdisc *qdisc); void qdisc_put(struct Qdisc *qdisc); +void qdisc_put_unlocked(struct Qdisc *qdisc); void qdisc_tree_reduce_backlog(struct Qdisc *qdisc, unsigned int n, unsigned int len); struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue, diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c index 2096138c4bf6..22e9799e5b69 100644 --- a/net/sched/sch_api.c +++ b/net/sched/sch_api.c @@ -314,6 +314,24 @@ out: return q; } +struct Qdisc *qdisc_lookup_rcu(struct net_device *dev, u32 handle) +{ + struct netdev_queue *nq; + struct Qdisc *q; + + if (!handle) + return NULL; + q = qdisc_match_from_root(dev->qdisc, handle); + if (q) + goto out; + + nq = dev_ingress_queue_rcu(dev); + if (nq) + q = qdisc_match_from_root(nq->qdisc_sleeping, handle); +out: + return q; +} + static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid) { unsigned long cl; diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 3e7696f3e053..531fac1d2875 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -941,6 +941,13 @@ void qdisc_free(struct Qdisc *qdisc) kfree((char *) qdisc - qdisc->padded); } +void qdisc_free_cb(struct rcu_head *head) +{ + struct Qdisc *q = container_of(head, struct Qdisc, rcu); + + qdisc_free(q); +} + static void qdisc_destroy(struct Qdisc *qdisc) { const struct Qdisc_ops *ops = qdisc->ops; @@ -970,7 +977,7 @@ static void qdisc_destroy(struct Qdisc *qdisc) kfree_skb_list(skb); } - qdisc_free(qdisc); + call_rcu(&qdisc->rcu, qdisc_free_cb); } void qdisc_put(struct Qdisc *qdisc) @@ -983,6 +990,22 @@ void qdisc_put(struct Qdisc *qdisc) } EXPORT_SYMBOL(qdisc_put); +/* Version of qdisc_put() that is called with rtnl mutex unlocked. + * Intended to be used as optimization, this function only takes rtnl lock if + * qdisc reference counter reached zero. + */ + +void qdisc_put_unlocked(struct Qdisc *qdisc) +{ + if (qdisc->flags & TCQ_F_BUILTIN || + !refcount_dec_and_rtnl_lock(&qdisc->refcnt)) + return; + + qdisc_destroy(qdisc); + rtnl_unlock(); +} +EXPORT_SYMBOL(qdisc_put_unlocked); + /* Attach toplevel qdisc to device queue. */ struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue, struct Qdisc *qdisc) |