diff options
Diffstat (limited to 'net/sched')
| -rw-r--r-- | net/sched/sch_sfq.c | 47 |
1 files changed, 31 insertions, 16 deletions
diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c index 3a23e30bc79e..b542c875e154 100644 --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -19,6 +19,7 @@ #include <linux/init.h> #include <linux/ipv6.h> #include <linux/skbuff.h> +#include <linux/jhash.h> #include <net/ip.h> #include <net/netlink.h> #include <net/pkt_sched.h> @@ -95,7 +96,7 @@ struct sfq_sched_data /* Variables */ struct timer_list perturb_timer; - int perturbation; + u32 perturbation; sfq_index tail; /* Index of current slot in round */ sfq_index max_depth; /* Maximal depth */ @@ -109,12 +110,7 @@ struct sfq_sched_data static __inline__ unsigned sfq_fold_hash(struct sfq_sched_data *q, u32 h, u32 h1) { - int pert = q->perturbation; - - /* Have we any rotation primitives? If not, WHY? */ - h ^= (h1<<pert) ^ (h1>>(0x1F - pert)); - h ^= h>>10; - return h & 0x3FF; + return jhash_2words(h, h1, q->perturbation) & (SFQ_HASH_DIVISOR - 1); } static unsigned sfq_hash(struct sfq_sched_data *q, struct sk_buff *skb) @@ -256,6 +252,13 @@ sfq_enqueue(struct sk_buff *skb, struct Qdisc* sch) q->ht[hash] = x = q->dep[SFQ_DEPTH].next; q->hash[x] = hash; } + /* If selected queue has length q->limit, this means that + * all another queues are empty and that we do simple tail drop, + * i.e. drop _this_ packet. + */ + if (q->qs[x].qlen >= q->limit) + return qdisc_drop(skb, sch); + sch->qstats.backlog += skb->len; __skb_queue_tail(&q->qs[x], skb); sfq_inc(q, x); @@ -294,6 +297,19 @@ sfq_requeue(struct sk_buff *skb, struct Qdisc* sch) } sch->qstats.backlog += skb->len; __skb_queue_head(&q->qs[x], skb); + /* If selected queue has length q->limit+1, this means that + * all another queues are empty and we do simple tail drop. + * This packet is still requeued at head of queue, tail packet + * is dropped. + */ + if (q->qs[x].qlen > q->limit) { + skb = q->qs[x].prev; + __skb_unlink(skb, &q->qs[x]); + sch->qstats.drops++; + sch->qstats.backlog -= skb->len; + kfree_skb(skb); + return NET_XMIT_CN; + } sfq_inc(q, x); if (q->qs[x].qlen == 1) { /* The flow is new */ if (q->tail == SFQ_DEPTH) { /* It is the first flow */ @@ -370,12 +386,10 @@ static void sfq_perturbation(unsigned long arg) struct Qdisc *sch = (struct Qdisc*)arg; struct sfq_sched_data *q = qdisc_priv(sch); - q->perturbation = net_random()&0x1F; + get_random_bytes(&q->perturbation, 4); - if (q->perturb_period) { - q->perturb_timer.expires = jiffies + q->perturb_period; - add_timer(&q->perturb_timer); - } + if (q->perturb_period) + mod_timer(&q->perturb_timer, jiffies + q->perturb_period); } static int sfq_change(struct Qdisc *sch, struct rtattr *opt) @@ -391,7 +405,7 @@ static int sfq_change(struct Qdisc *sch, struct rtattr *opt) q->quantum = ctl->quantum ? : psched_mtu(sch->dev); q->perturb_period = ctl->perturb_period*HZ; if (ctl->limit) - q->limit = min_t(u32, ctl->limit, SFQ_DEPTH - 2); + q->limit = min_t(u32, ctl->limit, SFQ_DEPTH - 1); qlen = sch->q.qlen; while (sch->q.qlen > q->limit) @@ -400,8 +414,8 @@ static int sfq_change(struct Qdisc *sch, struct rtattr *opt) del_timer(&q->perturb_timer); if (q->perturb_period) { - q->perturb_timer.expires = jiffies + q->perturb_period; - add_timer(&q->perturb_timer); + mod_timer(&q->perturb_timer, jiffies + q->perturb_period); + get_random_bytes(&q->perturbation, 4); } sch_tree_unlock(sch); return 0; @@ -423,12 +437,13 @@ static int sfq_init(struct Qdisc *sch, struct rtattr *opt) q->dep[i+SFQ_DEPTH].next = i+SFQ_DEPTH; q->dep[i+SFQ_DEPTH].prev = i+SFQ_DEPTH; } - q->limit = SFQ_DEPTH - 2; + q->limit = SFQ_DEPTH - 1; q->max_depth = 0; q->tail = SFQ_DEPTH; if (opt == NULL) { q->quantum = psched_mtu(sch->dev); q->perturb_period = 0; + get_random_bytes(&q->perturbation, 4); } else { int err = sfq_change(sch, opt); if (err) |