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| author | Stephen Hemminger <shemminger@linux-foundation.org> | 2007-03-22 12:17:05 -0700 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2007-04-25 22:27:21 -0700 |
| commit | 075aa573b74a732aeff487ab77d3fbd627c10856 (patch) | |
| tree | ba787170f860875318a13e4c934dc02a0304a18f | |
| parent | b407621c35ed5f9a0734e57472e9539117963768 (diff) | |
| download | linux-stable-075aa573b74a732aeff487ab77d3fbd627c10856.tar.gz linux-stable-075aa573b74a732aeff487ab77d3fbd627c10856.tar.bz2 linux-stable-075aa573b74a732aeff487ab77d3fbd627c10856.zip | |
[NETEM]: Optimize tfifo
In most cases, the next packet will be sent after the
last one. So optimize that case.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/sched/sch_netem.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c index 4ac6df0a5b35..7e9e658d4d93 100644 --- a/net/sched/sch_netem.c +++ b/net/sched/sch_netem.c @@ -479,22 +479,28 @@ static int netem_change(struct Qdisc *sch, struct rtattr *opt) */ struct fifo_sched_data { u32 limit; + psched_time_t oldest; }; static int tfifo_enqueue(struct sk_buff *nskb, struct Qdisc *sch) { struct fifo_sched_data *q = qdisc_priv(sch); struct sk_buff_head *list = &sch->q; - const struct netem_skb_cb *ncb - = (const struct netem_skb_cb *)nskb->cb; + psched_time_t tnext = ((struct netem_skb_cb *)nskb->cb)->time_to_send; struct sk_buff *skb; if (likely(skb_queue_len(list) < q->limit)) { + /* Optimize for add at tail */ + if (likely(skb_queue_empty(list) || !PSCHED_TLESS(tnext, q->oldest))) { + q->oldest = tnext; + return qdisc_enqueue_tail(nskb, sch); + } + skb_queue_reverse_walk(list, skb) { const struct netem_skb_cb *cb = (const struct netem_skb_cb *)skb->cb; - if (!PSCHED_TLESS(ncb->time_to_send, cb->time_to_send)) + if (!PSCHED_TLESS(tnext, cb->time_to_send)) break; } @@ -507,7 +513,7 @@ static int tfifo_enqueue(struct sk_buff *nskb, struct Qdisc *sch) return NET_XMIT_SUCCESS; } - return qdisc_drop(nskb, sch); + return qdisc_reshape_fail(nskb, sch); } static int tfifo_init(struct Qdisc *sch, struct rtattr *opt) @@ -523,6 +529,7 @@ static int tfifo_init(struct Qdisc *sch, struct rtattr *opt) } else q->limit = max_t(u32, sch->dev->tx_queue_len, 1); + PSCHED_SET_PASTPERFECT(q->oldest); return 0; } |