diff options
Diffstat (limited to 'net/sched/sch_netem.c')
-rw-r--r-- | net/sched/sch_netem.c | 108 |
1 files changed, 53 insertions, 55 deletions
diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c index 1ccbfb5..5d9d8bc 100644 --- a/net/sched/sch_netem.c +++ b/net/sched/sch_netem.c @@ -22,6 +22,7 @@ #include <linux/skbuff.h> #include <linux/rtnetlink.h> +#include <net/netlink.h> #include <net/pkt_sched.h> #define VERSION "1.2" @@ -54,21 +55,22 @@ struct netem_sched_data { struct Qdisc *qdisc; - struct timer_list timer; + struct qdisc_watchdog watchdog; + + psched_tdiff_t latency; + psched_tdiff_t jitter; - u32 latency; u32 loss; u32 limit; u32 counter; u32 gap; - u32 jitter; u32 duplicate; u32 reorder; u32 corrupt; struct crndstate { - unsigned long last; - unsigned long rho; + u32 last; + u32 rho; } delay_cor, loss_cor, dup_cor, reorder_cor, corrupt_cor; struct disttable { @@ -95,12 +97,12 @@ static void init_crandom(struct crndstate *state, unsigned long rho) * Next number depends on last value. * rho is scaled to avoid floating point. */ -static unsigned long get_crandom(struct crndstate *state) +static u32 get_crandom(struct crndstate *state) { u64 value, rho; unsigned long answer; - if (state->rho == 0) /* no correllation */ + if (state->rho == 0) /* no correlation */ return net_random(); value = net_random(); @@ -114,11 +116,13 @@ static unsigned long get_crandom(struct crndstate *state) * std deviation sigma. Uses table lookup to approximate the desired * distribution, and a uniformly-distributed pseudo-random source. */ -static long tabledist(unsigned long mu, long sigma, - struct crndstate *state, const struct disttable *dist) +static psched_tdiff_t tabledist(psched_tdiff_t mu, psched_tdiff_t sigma, + struct crndstate *state, + const struct disttable *dist) { - long t, x; - unsigned long rnd; + psched_tdiff_t x; + long t; + u32 rnd; if (sigma == 0) return mu; @@ -213,8 +217,8 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch) delay = tabledist(q->latency, q->jitter, &q->delay_cor, q->delay_dist); - PSCHED_GET_TIME(now); - PSCHED_TADD2(now, delay, cb->time_to_send); + now = psched_get_time(); + cb->time_to_send = now + delay; ++q->counter; ret = q->qdisc->enqueue(skb, q->qdisc); } else { @@ -222,7 +226,7 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch) * Do re-ordering by putting one out of N packets at the front * of the queue. */ - PSCHED_GET_TIME(cb->time_to_send); + cb->time_to_send = psched_get_time(); q->counter = 0; ret = q->qdisc->ops->requeue(skb, q->qdisc); } @@ -269,55 +273,43 @@ static struct sk_buff *netem_dequeue(struct Qdisc *sch) struct netem_sched_data *q = qdisc_priv(sch); struct sk_buff *skb; + smp_mb(); + if (sch->flags & TCQ_F_THROTTLED) + return NULL; + skb = q->qdisc->dequeue(q->qdisc); if (skb) { const struct netem_skb_cb *cb = (const struct netem_skb_cb *)skb->cb; - psched_time_t now; + psched_time_t now = psched_get_time(); /* if more time remaining? */ - PSCHED_GET_TIME(now); - - if (PSCHED_TLESS(cb->time_to_send, now)) { + if (cb->time_to_send <= now) { pr_debug("netem_dequeue: return skb=%p\n", skb); sch->q.qlen--; - sch->flags &= ~TCQ_F_THROTTLED; return skb; - } else { - psched_tdiff_t delay = PSCHED_TDIFF(cb->time_to_send, now); - - if (q->qdisc->ops->requeue(skb, q->qdisc) != NET_XMIT_SUCCESS) { - qdisc_tree_decrease_qlen(q->qdisc, 1); - sch->qstats.drops++; - printk(KERN_ERR "netem: queue discpline %s could not requeue\n", - q->qdisc->ops->id); - } + } - mod_timer(&q->timer, jiffies + PSCHED_US2JIFFIE(delay)); - sch->flags |= TCQ_F_THROTTLED; + if (unlikely(q->qdisc->ops->requeue(skb, q->qdisc) != NET_XMIT_SUCCESS)) { + qdisc_tree_decrease_qlen(q->qdisc, 1); + sch->qstats.drops++; + printk(KERN_ERR "netem: %s could not requeue\n", + q->qdisc->ops->id); } + + qdisc_watchdog_schedule(&q->watchdog, cb->time_to_send); } return NULL; } -static void netem_watchdog(unsigned long arg) -{ - struct Qdisc *sch = (struct Qdisc *)arg; - - pr_debug("netem_watchdog qlen=%d\n", sch->q.qlen); - sch->flags &= ~TCQ_F_THROTTLED; - netif_schedule(sch->dev); -} - static void netem_reset(struct Qdisc *sch) { struct netem_sched_data *q = qdisc_priv(sch); qdisc_reset(q->qdisc); sch->q.qlen = 0; - sch->flags &= ~TCQ_F_THROTTLED; - del_timer_sync(&q->timer); + qdisc_watchdog_cancel(&q->watchdog); } /* Pass size change message down to embedded FIFO */ @@ -438,10 +430,11 @@ static int netem_change(struct Qdisc *sch, struct rtattr *opt) q->loss = qopt->loss; q->duplicate = qopt->duplicate; - /* for compatiablity with earlier versions. - * if gap is set, need to assume 100% probablity + /* for compatibility with earlier versions. + * if gap is set, need to assume 100% probability */ - q->reorder = ~0; + if (q->gap) + q->reorder = ~0; /* Handle nested options after initial queue options. * Should have put all options in nested format but too late now. @@ -487,22 +480,28 @@ 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) || 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 (tnext >= cb->time_to_send) break; } @@ -515,7 +514,7 @@ 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) @@ -531,6 +530,7 @@ static int tfifo_init(struct Qdisc *sch, struct rtattr *opt) } else q->limit = max_t(u32, sch->dev->tx_queue_len, 1); + q->oldest = PSCHED_PASTPERFECT; return 0; } @@ -567,9 +567,7 @@ static int netem_init(struct Qdisc *sch, struct rtattr *opt) if (!opt) return -EINVAL; - init_timer(&q->timer); - q->timer.function = netem_watchdog; - q->timer.data = (unsigned long) sch; + qdisc_watchdog_init(&q->watchdog, sch); q->qdisc = qdisc_create_dflt(sch->dev, &tfifo_qdisc_ops, TC_H_MAKE(sch->handle, 1)); @@ -590,7 +588,7 @@ static void netem_destroy(struct Qdisc *sch) { struct netem_sched_data *q = qdisc_priv(sch); - del_timer_sync(&q->timer); + qdisc_watchdog_cancel(&q->watchdog); qdisc_destroy(q->qdisc); kfree(q->delay_dist); } @@ -598,7 +596,7 @@ static void netem_destroy(struct Qdisc *sch) static int netem_dump(struct Qdisc *sch, struct sk_buff *skb) { const struct netem_sched_data *q = qdisc_priv(sch); - unsigned char *b = skb->tail; + unsigned char *b = skb_tail_pointer(skb); struct rtattr *rta = (struct rtattr *) b; struct tc_netem_qopt qopt; struct tc_netem_corr cor; @@ -626,12 +624,12 @@ static int netem_dump(struct Qdisc *sch, struct sk_buff *skb) corrupt.correlation = q->corrupt_cor.rho; RTA_PUT(skb, TCA_NETEM_CORRUPT, sizeof(corrupt), &corrupt); - rta->rta_len = skb->tail - b; + rta->rta_len = skb_tail_pointer(skb) - b; return skb->len; rtattr_failure: - skb_trim(skb, b - skb->data); + nlmsg_trim(skb, b); return -1; } |