diff options
| -rw-r--r-- | include/net/sch_generic.h | 1 | ||||
| -rw-r--r-- | net/core/dev.c | 26 | ||||
| -rw-r--r-- | net/sched/sch_generic.c | 30 |
3 files changed, 43 insertions, 14 deletions
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index 7dd8b0b..77791fa 100644 --- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -71,6 +71,7 @@ struct Qdisc { * qdisc_tree_decrease_qlen() should stop. */ #define TCQ_F_INVISIBLE 0x80 /* invisible by default in dump */ +#define TCQ_F_NOLOCK 0x100 /* qdisc does not require locking */ u32 limit; const struct Qdisc_ops *ops; struct qdisc_size_table __rcu *stab; diff --git a/net/core/dev.c b/net/core/dev.c index 44c7de3..e32cf5c 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3162,6 +3162,21 @@ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, int rc; qdisc_calculate_pkt_len(skb, q); + + if (q->flags & TCQ_F_NOLOCK) { + if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) { + __qdisc_drop(skb, &to_free); + rc = NET_XMIT_DROP; + } else { + rc = q->enqueue(skb, q, &to_free) & NET_XMIT_MASK; + __qdisc_run(q); + } + + if (unlikely(to_free)) + kfree_skb_list(to_free); + return rc; + } + /* * Heuristic to force contended enqueues to serialize on a * separate lock before trying to get qdisc main lock. @@ -4144,19 +4159,22 @@ static __latent_entropy void net_tx_action(struct softirq_action *h) while (head) { struct Qdisc *q = head; - spinlock_t *root_lock; + spinlock_t *root_lock = NULL; head = head->next_sched; - root_lock = qdisc_lock(q); - spin_lock(root_lock); + if (!(q->flags & TCQ_F_NOLOCK)) { + root_lock = qdisc_lock(q); + spin_lock(root_lock); + } /* We need to make sure head->next_sched is read * before clearing __QDISC_STATE_SCHED */ smp_mb__before_atomic(); clear_bit(__QDISC_STATE_SCHED, &q->state); qdisc_run(q); - spin_unlock(root_lock); + if (root_lock) + spin_unlock(root_lock); } } } diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index f6803e1..ec757f6 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -174,7 +174,8 @@ int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, int ret = NETDEV_TX_BUSY; /* And release qdisc */ - spin_unlock(root_lock); + if (root_lock) + spin_unlock(root_lock); /* Note that we validate skb (GSO, checksum, ...) outside of locks */ if (validate) @@ -187,10 +188,13 @@ int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, HARD_TX_UNLOCK(dev, txq); } else { - spin_lock(root_lock); + if (root_lock) + spin_lock(root_lock); return qdisc_qlen(q); } - spin_lock(root_lock); + + if (root_lock) + spin_lock(root_lock); if (dev_xmit_complete(ret)) { /* Driver sent out skb successfully or skb was consumed */ @@ -231,9 +235,9 @@ int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, */ static inline int qdisc_restart(struct Qdisc *q, int *packets) { + spinlock_t *root_lock = NULL; struct netdev_queue *txq; struct net_device *dev; - spinlock_t *root_lock; struct sk_buff *skb; bool validate; @@ -242,7 +246,9 @@ static inline int qdisc_restart(struct Qdisc *q, int *packets) if (unlikely(!skb)) return 0; - root_lock = qdisc_lock(q); + if (!(q->flags & TCQ_F_NOLOCK)) + root_lock = qdisc_lock(q); + dev = qdisc_dev(q); txq = skb_get_tx_queue(dev, skb); @@ -880,14 +886,18 @@ static bool some_qdisc_is_busy(struct net_device *dev) dev_queue = netdev_get_tx_queue(dev, i); q = dev_queue->qdisc_sleeping; - root_lock = qdisc_lock(q); - spin_lock_bh(root_lock); + if (q->flags & TCQ_F_NOLOCK) { + val = test_bit(__QDISC_STATE_SCHED, &q->state); + } else { + root_lock = qdisc_lock(q); + spin_lock_bh(root_lock); - val = (qdisc_is_running(q) || - test_bit(__QDISC_STATE_SCHED, &q->state)); + val = (qdisc_is_running(q) || + test_bit(__QDISC_STATE_SCHED, &q->state)); - spin_unlock_bh(root_lock); + spin_unlock_bh(root_lock); + } if (val) return true; |
