diff options
| author | Hagen Paul Pfeifer <hagen@jauu.net> | 2010-01-24 15:30:59 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-01-29 08:27:00 +0300 |
| commit | 57dbb2d83d100ea601c54fe129bfde0678db5dee (patch) | |
| tree | 40305bcd986692f512b1b5e848c0b0f612968c6a /include/net | |
| parent | d74340d31bf1dbeb00acadddd8697666528a7846 (diff) | |
| download | linux-57dbb2d83d100ea601c54fe129bfde0678db5dee.tar.xz | |
sched: add head drop fifo queue
This adds an additional queuing strategy, called pfifo_head_drop,
to remove the oldest skb in the case of an overflow within the queue -
the head element - instead of the last skb (tail). To remove the oldest
skb in congested situations is useful for sensor network environments
where newer packets reflect the superior information.
Reviewed-by: Florian Westphal <fw@strlen.de>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net')
| -rw-r--r-- | include/net/pkt_sched.h | 1 | ||||
| -rw-r--r-- | include/net/sch_generic.h | 19 |
2 files changed, 20 insertions, 0 deletions
diff --git a/include/net/pkt_sched.h b/include/net/pkt_sched.h index 2d567265363e..b6cdc33b39c1 100644 --- a/include/net/pkt_sched.h +++ b/include/net/pkt_sched.h @@ -71,6 +71,7 @@ extern void qdisc_watchdog_cancel(struct qdisc_watchdog *wd); extern struct Qdisc_ops pfifo_qdisc_ops; extern struct Qdisc_ops bfifo_qdisc_ops; +extern struct Qdisc_ops pfifo_head_drop_qdisc_ops; extern int fifo_set_limit(struct Qdisc *q, unsigned int limit); extern struct Qdisc *fifo_create_dflt(struct Qdisc *sch, struct Qdisc_ops *ops, diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index dad558bc06fa..67dc08eaaa45 100644 --- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -427,6 +427,25 @@ static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch) return __qdisc_dequeue_head(sch, &sch->q); } +static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch, + struct sk_buff_head *list) +{ + struct sk_buff *skb = __qdisc_dequeue_head(sch, list); + + if (likely(skb != NULL)) { + unsigned int len = qdisc_pkt_len(skb); + kfree_skb(skb); + return len; + } + + return 0; +} + +static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch) +{ + return __qdisc_queue_drop_head(sch, &sch->q); +} + static inline struct sk_buff *__qdisc_dequeue_tail(struct Qdisc *sch, struct sk_buff_head *list) { |