diff options
| author | Jarek Poplawski <jarkao2@gmail.com> | 2008-09-22 22:16:23 -0700 | 
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2008-09-22 22:16:23 -0700 | 
| commit | ebf059821ed8a36acd706484b719d14d212ada32 (patch) | |
| tree | 44b2ee2887113ea5d90b35f4c4ae1a376f38e94f /net/sched/sch_generic.c | |
| parent | f0876520b0b721bedafd9cec3b1b0624ae566eee (diff) | |
pkt_sched: Check the state of tx_queue in dequeue_skb()
Check in dequeue_skb() the state of tx_queue for requeued skb to save
on locking and re-requeuing, and possibly remove the current check in
qdisc_run(). Based on the idea of Alexander Duyck.
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/sched/sch_generic.c')
| -rw-r--r-- | net/sched/sch_generic.c | 18 | 
1 files changed, 14 insertions, 4 deletions
| diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 1b508bd1c06c..5e7e0bd38fe8 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -52,11 +52,21 @@ static inline int dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q)  static inline struct sk_buff *dequeue_skb(struct Qdisc *q)  { -	struct sk_buff *skb; - -	skb = __skb_dequeue(&q->requeue); -	if (!skb) +	struct sk_buff *skb = skb_peek(&q->requeue); + +	if (unlikely(skb)) { +		struct net_device *dev = qdisc_dev(q); +		struct netdev_queue *txq; + +		/* check the reason of requeuing without tx lock first */ +		txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb)); +		if (!netif_tx_queue_stopped(txq) && !netif_tx_queue_frozen(txq)) +			__skb_unlink(skb, &q->requeue); +		else +			skb = NULL; +	} else {  		skb = q->dequeue(q); +	}  	return skb;  } | 
