From: Krishna Kumar Date: Mon, 25 Jun 2007 02:57:27 +0000 (-0700) Subject: [NET]: qdisc_restart - couple of optimizations. X-Git-Tag: v2.6.23-rc1~1109^2~136 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e50c41b53d7aa48152dd9c633b04fc7abd536f1f;p=linux-2.6 [NET]: qdisc_restart - couple of optimizations. Changes : - netif_queue_stopped need not be called inside qdisc_restart as it has been called already in qdisc_run() before the first skb is sent, and in __qdisc_run() after each intermediate skb is sent (note : we are the only sender, so the queue cannot get stopped while the tx lock was got in the ~LLTX case). - BUG_ON((int) q->q.qlen < 0) was a relic from old times when -1 meant more packets are available, and __qdisc_run used to loop when qdisc_restart() returned -1. During those days, it was necessary to make sure that qlen is never less than zero, since __qdisc_run would get into an infinite loop if no packets are on the queue and this bug in qdisc was there (and worse - no more skbs could ever get queue'd as we hold the queue lock too). With Herbert's recent change to return values, this check is not required. Hopefully Herbert can validate this change. If at all this is required, it should be added to skb_dequeue (in failure case), and not to qdisc_qlen. Signed-off-by: Krishna Kumar Signed-off-by: David S. Miller --- diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 983c32caf7..2488dbb17b 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -61,7 +61,6 @@ void qdisc_unlock_tree(struct net_device *dev) static inline int qdisc_qlen(struct Qdisc *q) { - BUG_ON((int) q->q.qlen < 0); return q->q.qlen; } @@ -167,9 +166,7 @@ static inline int qdisc_restart(struct net_device *dev) /* And release queue */ spin_unlock(&dev->queue_lock); - ret = NETDEV_TX_BUSY; - if (!netif_queue_stopped(dev)) - ret = dev_hard_start_xmit(skb, dev); + ret = dev_hard_start_xmit(skb, dev); if (!lockless) netif_tx_unlock(dev);