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-rw-r--r--net/sched/sch_sfq.c247
1 files changed, 201 insertions, 46 deletions
diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c
index 7a90df655..7cc2b6e5f 100644
--- a/net/sched/sch_sfq.c
+++ b/net/sched/sch_sfq.c
@@ -1,5 +1,5 @@
/*
- * net/sched/sch_sfq.c Stochastic Fairness Queueing scheduler.
+ * net/sched/sch_sfq.c Stochastic Fairness Queueing discipline.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
@@ -9,6 +9,8 @@
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
*/
+#include <linux/config.h>
+#include <linux/module.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/bitops.h>
@@ -30,6 +32,7 @@
#include <linux/notifier.h>
#include <linux/init.h>
#include <net/ip.h>
+#include <linux/ipv6.h>
#include <net/route.h>
#include <linux/skbuff.h>
#include <net/sock.h>
@@ -84,14 +87,12 @@
scattered over different locations. It is not good,
but it allowed to put it into 4K.
- It is easy to increase these values.
+ It is easy to increase these values, but not in flight.
*/
#define SFQ_DEPTH 128
#define SFQ_HASH_DIVISOR 1024
-#define SFQ_HASH(a) 0
-
/* This type should contain at least SFQ_DEPTH*2 values */
typedef unsigned char sfq_index;
@@ -104,9 +105,12 @@ struct sfq_head
struct sfq_sched_data
{
/* Parameters */
+ int perturb_period;
unsigned quantum; /* Allotment per round: MUST BE >= MTU */
/* Variables */
+ struct timer_list perturb_timer;
+ int perturbation;
sfq_index tail; /* Index of current slot in round */
sfq_index max_depth; /* Maximal depth */
@@ -118,10 +122,59 @@ struct sfq_sched_data
struct sfq_head dep[SFQ_DEPTH*2]; /* Linked list of slots, indexed by depth */
};
+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;
+}
+
+#ifndef IPPROTO_ESP
+#define IPPROTO_ESP 50
+#endif
+
+static unsigned sfq_hash(struct sfq_sched_data *q, struct sk_buff *skb)
+{
+ u32 h, h2;
+
+ switch (skb->protocol) {
+ case __constant_htons(ETH_P_IP):
+ {
+ struct iphdr *iph = skb->nh.iph;
+ h = iph->daddr;
+ h2 = iph->saddr^iph->protocol;
+ if (!(iph->frag_off&htons(IP_MF|IP_OFFSET)) &&
+ (iph->protocol == IPPROTO_TCP ||
+ iph->protocol == IPPROTO_UDP ||
+ iph->protocol == IPPROTO_ESP))
+ h2 ^= *(((u32*)iph) + iph->ihl);
+ break;
+ }
+ case __constant_htons(ETH_P_IPV6):
+ {
+ struct ipv6hdr *iph = skb->nh.ipv6h;
+ h = iph->daddr.s6_addr32[3];
+ h2 = iph->saddr.s6_addr32[3]^iph->nexthdr;
+ if (iph->nexthdr == IPPROTO_TCP ||
+ iph->nexthdr == IPPROTO_UDP ||
+ iph->nexthdr == IPPROTO_ESP)
+ h2 ^= *(u32*)&iph[1];
+ break;
+ }
+ default:
+ h = (u32)(unsigned long)skb->dst^skb->protocol;
+ h2 = (u32)(unsigned long)skb->sk;
+ }
+ return sfq_fold_hash(q, h, h2);
+}
+
extern __inline__ void sfq_link(struct sfq_sched_data *q, sfq_index x)
{
sfq_index p, n;
- int d = q->qs[x].qlen;
+ int d = q->qs[x].qlen + SFQ_DEPTH;
p = d;
n = q->dep[d].next;
@@ -161,47 +214,49 @@ extern __inline__ void sfq_inc(struct sfq_sched_data *q, sfq_index x)
sfq_link(q, x);
}
-static __inline__ void sfq_drop(struct sfq_sched_data *q)
+static int sfq_drop(struct Qdisc *sch)
{
- struct sk_buff *skb;
+ struct sfq_sched_data *q = (struct sfq_sched_data *)sch->data;
sfq_index d = q->max_depth;
+ struct sk_buff *skb;
/* Queue is full! Find the longest slot and
drop a packet from it */
- if (d != 1) {
- sfq_index x = q->dep[d].next;
+ if (d > 1) {
+ sfq_index x = q->dep[d+SFQ_DEPTH].next;
skb = q->qs[x].prev;
__skb_unlink(skb, &q->qs[x]);
kfree_skb(skb);
sfq_dec(q, x);
-/*
sch->q.qlen--;
- */
- return;
+ sch->stats.drops++;
+ return 1;
}
- /* It is difficult to believe, but ALL THE SLOTS HAVE LENGTH 1. */
+ if (d == 1) {
+ /* It is difficult to believe, but ALL THE SLOTS HAVE LENGTH 1. */
+ d = q->next[q->tail];
+ q->next[q->tail] = q->next[d];
+ q->allot[q->next[d]] += q->quantum;
+ skb = q->qs[d].prev;
+ __skb_unlink(skb, &q->qs[d]);
+ kfree_skb(skb);
+ sfq_dec(q, d);
+ sch->q.qlen--;
+ q->ht[q->hash[d]] = SFQ_DEPTH;
+ sch->stats.drops++;
+ return 1;
+ }
- d = q->next[q->tail];
- q->next[q->tail] = q->next[d];
- q->allot[q->next[d]] += q->quantum;
- skb = q->qs[d].prev;
- __skb_unlink(skb, &q->qs[d]);
- kfree_skb(skb);
- sfq_dec(q, d);
-/*
- sch->q.qlen--;
- */
- q->ht[q->hash[d]] = SFQ_DEPTH;
- return;
+ return 0;
}
static int
sfq_enqueue(struct sk_buff *skb, struct Qdisc* sch)
{
struct sfq_sched_data *q = (struct sfq_sched_data *)sch->data;
- unsigned hash = SFQ_HASH(skb);
+ unsigned hash = sfq_hash(q, skb);
sfq_index x;
x = q->ht[hash];
@@ -222,13 +277,52 @@ sfq_enqueue(struct sk_buff *skb, struct Qdisc* sch)
q->tail = x;
}
}
+ if (++sch->q.qlen < SFQ_DEPTH-1) {
+ sch->stats.bytes += skb->len;
+ sch->stats.packets++;
+ return 1;
+ }
+
+ sfq_drop(sch);
+ return 0;
+}
+
+static int
+sfq_requeue(struct sk_buff *skb, struct Qdisc* sch)
+{
+ struct sfq_sched_data *q = (struct sfq_sched_data *)sch->data;
+ unsigned hash = sfq_hash(q, skb);
+ sfq_index x;
+
+ x = q->ht[hash];
+ if (x == SFQ_DEPTH) {
+ q->ht[hash] = x = q->dep[SFQ_DEPTH].next;
+ q->hash[x] = hash;
+ }
+ __skb_queue_head(&q->qs[x], skb);
+ sfq_inc(q, x);
+ if (q->qs[x].qlen == 1) { /* The flow is new */
+ if (q->tail == SFQ_DEPTH) { /* It is the first flow */
+ q->tail = x;
+ q->next[x] = x;
+ q->allot[x] = q->quantum;
+ } else {
+ q->next[x] = q->next[q->tail];
+ q->next[q->tail] = x;
+ q->tail = x;
+ }
+ }
if (++sch->q.qlen < SFQ_DEPTH-1)
return 1;
- sfq_drop(q);
+ sch->stats.drops++;
+ sfq_drop(sch);
return 0;
}
+
+
+
static struct sk_buff *
sfq_dequeue(struct Qdisc* sch)
{
@@ -273,13 +367,28 @@ sfq_reset(struct Qdisc* sch)
kfree_skb(skb);
}
+static void sfq_perturbation(unsigned long arg)
+{
+ struct Qdisc *sch = (struct Qdisc*)arg;
+ struct sfq_sched_data *q = (struct sfq_sched_data *)sch->data;
+
+ q->perturbation = net_random()&0x1F;
+ q->perturb_timer.expires = jiffies + q->perturb_period;
-static int sfq_open(struct Qdisc *sch, void *arg)
+ if (q->perturb_period) {
+ q->perturb_timer.expires = jiffies + q->perturb_period;
+ add_timer(&q->perturb_timer);
+ }
+}
+
+static int sfq_init(struct Qdisc *sch, struct rtattr *opt)
{
- struct sfq_sched_data *q;
+ struct sfq_sched_data *q = (struct sfq_sched_data *)sch->data;
int i;
- q = (struct sfq_sched_data *)sch->data;
+ q->perturb_timer.data = (unsigned long)sch;
+ q->perturb_timer.function = sfq_perturbation;
+ init_timer(&q->perturb_timer);
for (i=0; i<SFQ_HASH_DIVISOR; i++)
q->ht[i] = SFQ_DEPTH;
@@ -290,43 +399,89 @@ static int sfq_open(struct Qdisc *sch, void *arg)
}
q->max_depth = 0;
q->tail = SFQ_DEPTH;
- q->quantum = sch->dev->mtu;
- if (sch->dev->hard_header)
- q->quantum += sch->dev->hard_header_len;
+ if (opt == NULL) {
+ q->quantum = sch->dev->mtu;
+ q->perturb_period = 0;
+ if (sch->dev->hard_header)
+ q->quantum += sch->dev->hard_header_len;
+ } else {
+ struct tc_sfq_qopt *ctl = RTA_DATA(opt);
+ if (opt->rta_len < RTA_LENGTH(sizeof(*ctl)))
+ return -EINVAL;
+ q->quantum = ctl->quantum ? : psched_mtu(sch->dev);
+ q->perturb_period = ctl->perturb_period*HZ;
+ /* The rest is compiled in */
+ }
for (i=0; i<SFQ_DEPTH; i++)
sfq_link(q, i);
+ if (q->perturb_period) {
+ q->perturb_timer.expires = jiffies + q->perturb_period;
+ add_timer(&q->perturb_timer);
+ }
+ MOD_INC_USE_COUNT;
return 0;
}
+static void sfq_destroy(struct Qdisc *sch)
+{
+ struct sfq_sched_data *q = (struct sfq_sched_data *)sch->data;
+ del_timer(&q->perturb_timer);
+ MOD_DEC_USE_COUNT;
+}
+
+#ifdef CONFIG_RTNETLINK
+static int sfq_dump(struct Qdisc *sch, struct sk_buff *skb)
+{
+ struct sfq_sched_data *q = (struct sfq_sched_data *)sch->data;
+ unsigned char *b = skb->tail;
+ struct tc_sfq_qopt opt;
+
+ opt.quantum = q->quantum;
+ opt.perturb_period = q->perturb_period/HZ;
+
+ opt.limit = SFQ_DEPTH;
+ opt.divisor = SFQ_HASH_DIVISOR;
+ opt.flows = SFQ_DEPTH;
+
+ RTA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
+
+ return skb->len;
+
+rtattr_failure:
+ skb_trim(skb, b - skb->data);
+ return -1;
+}
+#endif
-struct Qdisc_ops sfq_ops =
+struct Qdisc_ops sfq_qdisc_ops =
{
NULL,
+ NULL,
"sfq",
- 0,
sizeof(struct sfq_sched_data),
+
sfq_enqueue,
sfq_dequeue,
+ sfq_requeue,
+ sfq_drop,
+
+ sfq_init,
sfq_reset,
- NULL,
- sfq_open,
+ sfq_destroy,
+
+#ifdef CONFIG_RTNETLINK
+ sfq_dump,
+#endif
};
#ifdef MODULE
int init_module(void)
{
- int err;
-
- /* Load once and never free it. */
- MOD_INC_USE_COUNT;
-
- err = register_qdisc(&sfq_ops);
- if (err)
- MOD_DEC_USE_COUNT;
- return err;
+ return register_qdisc(&sfq_qdisc_ops);
}
void cleanup_module(void)
{
+ unregister_qdisc(&sfq_qdisc_ops);
}
#endif