summaryrefslogtreecommitdiff
path: root/net/sched/sch_gred.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/sched/sch_gred.c')
-rw-r--r--net/sched/sch_gred.c630
1 files changed, 630 insertions, 0 deletions
diff --git a/net/sched/sch_gred.c b/net/sched/sch_gred.c
new file mode 100644
index 000000000000..25c171c32715
--- /dev/null
+++ b/net/sched/sch_gred.c
@@ -0,0 +1,630 @@
+/*
+ * net/sched/sch_gred.c Generic Random Early Detection queue.
+ *
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Authors: J Hadi Salim (hadi@cyberus.ca) 1998-2002
+ *
+ * 991129: - Bug fix with grio mode
+ * - a better sing. AvgQ mode with Grio(WRED)
+ * - A finer grained VQ dequeue based on sugestion
+ * from Ren Liu
+ * - More error checks
+ *
+ *
+ *
+ * For all the glorious comments look at Alexey's sch_red.c
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <linux/bitops.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/in.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/if_ether.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/notifier.h>
+#include <net/ip.h>
+#include <net/route.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/pkt_sched.h>
+
+#if 1 /* control */
+#define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
+#else
+#define DPRINTK(format,args...)
+#endif
+
+#if 0 /* data */
+#define D2PRINTK(format,args...) printk(KERN_DEBUG format,##args)
+#else
+#define D2PRINTK(format,args...)
+#endif
+
+struct gred_sched_data;
+struct gred_sched;
+
+struct gred_sched_data
+{
+/* Parameters */
+ u32 limit; /* HARD maximal queue length */
+ u32 qth_min; /* Min average length threshold: A scaled */
+ u32 qth_max; /* Max average length threshold: A scaled */
+ u32 DP; /* the drop pramaters */
+ char Wlog; /* log(W) */
+ char Plog; /* random number bits */
+ u32 Scell_max;
+ u32 Rmask;
+ u32 bytesin; /* bytes seen on virtualQ so far*/
+ u32 packetsin; /* packets seen on virtualQ so far*/
+ u32 backlog; /* bytes on the virtualQ */
+ u32 forced; /* packets dropped for exceeding limits */
+ u32 early; /* packets dropped as a warning */
+ u32 other; /* packets dropped by invoking drop() */
+ u32 pdrop; /* packets dropped because we exceeded physical queue limits */
+ char Scell_log;
+ u8 Stab[256];
+ u8 prio; /* the prio of this vq */
+
+/* Variables */
+ unsigned long qave; /* Average queue length: A scaled */
+ int qcount; /* Packets since last random number generation */
+ u32 qR; /* Cached random number */
+
+ psched_time_t qidlestart; /* Start of idle period */
+};
+
+struct gred_sched
+{
+ struct gred_sched_data *tab[MAX_DPs];
+ u32 DPs;
+ u32 def;
+ u8 initd;
+ u8 grio;
+ u8 eqp;
+};
+
+static int
+gred_enqueue(struct sk_buff *skb, struct Qdisc* sch)
+{
+ psched_time_t now;
+ struct gred_sched_data *q=NULL;
+ struct gred_sched *t= qdisc_priv(sch);
+ unsigned long qave=0;
+ int i=0;
+
+ if (!t->initd && skb_queue_len(&sch->q) < (sch->dev->tx_queue_len ? : 1)) {
+ D2PRINTK("NO GRED Queues setup yet! Enqueued anyway\n");
+ goto do_enqueue;
+ }
+
+
+ if ( ((skb->tc_index&0xf) > (t->DPs -1)) || !(q=t->tab[skb->tc_index&0xf])) {
+ printk("GRED: setting to default (%d)\n ",t->def);
+ if (!(q=t->tab[t->def])) {
+ DPRINTK("GRED: setting to default FAILED! dropping!! "
+ "(%d)\n ", t->def);
+ goto drop;
+ }
+ /* fix tc_index? --could be controvesial but needed for
+ requeueing */
+ skb->tc_index=(skb->tc_index&0xfffffff0) | t->def;
+ }
+
+ D2PRINTK("gred_enqueue virtualQ 0x%x classid %x backlog %d "
+ "general backlog %d\n",skb->tc_index&0xf,sch->handle,q->backlog,
+ sch->qstats.backlog);
+ /* sum up all the qaves of prios <= to ours to get the new qave*/
+ if (!t->eqp && t->grio) {
+ for (i=0;i<t->DPs;i++) {
+ if ((!t->tab[i]) || (i==q->DP))
+ continue;
+
+ if ((t->tab[i]->prio < q->prio) && (PSCHED_IS_PASTPERFECT(t->tab[i]->qidlestart)))
+ qave +=t->tab[i]->qave;
+ }
+
+ }
+
+ q->packetsin++;
+ q->bytesin+=skb->len;
+
+ if (t->eqp && t->grio) {
+ qave=0;
+ q->qave=t->tab[t->def]->qave;
+ q->qidlestart=t->tab[t->def]->qidlestart;
+ }
+
+ if (!PSCHED_IS_PASTPERFECT(q->qidlestart)) {
+ long us_idle;
+ PSCHED_GET_TIME(now);
+ us_idle = PSCHED_TDIFF_SAFE(now, q->qidlestart, q->Scell_max);
+ PSCHED_SET_PASTPERFECT(q->qidlestart);
+
+ q->qave >>= q->Stab[(us_idle>>q->Scell_log)&0xFF];
+ } else {
+ if (t->eqp) {
+ q->qave += sch->qstats.backlog - (q->qave >> q->Wlog);
+ } else {
+ q->qave += q->backlog - (q->qave >> q->Wlog);
+ }
+
+ }
+
+
+ if (t->eqp && t->grio)
+ t->tab[t->def]->qave=q->qave;
+
+ if ((q->qave+qave) < q->qth_min) {
+ q->qcount = -1;
+enqueue:
+ if (q->backlog + skb->len <= q->limit) {
+ q->backlog += skb->len;
+do_enqueue:
+ __skb_queue_tail(&sch->q, skb);
+ sch->qstats.backlog += skb->len;
+ sch->bstats.bytes += skb->len;
+ sch->bstats.packets++;
+ return 0;
+ } else {
+ q->pdrop++;
+ }
+
+drop:
+ kfree_skb(skb);
+ sch->qstats.drops++;
+ return NET_XMIT_DROP;
+ }
+ if ((q->qave+qave) >= q->qth_max) {
+ q->qcount = -1;
+ sch->qstats.overlimits++;
+ q->forced++;
+ goto drop;
+ }
+ if (++q->qcount) {
+ if ((((qave+q->qave) - q->qth_min)>>q->Wlog)*q->qcount < q->qR)
+ goto enqueue;
+ q->qcount = 0;
+ q->qR = net_random()&q->Rmask;
+ sch->qstats.overlimits++;
+ q->early++;
+ goto drop;
+ }
+ q->qR = net_random()&q->Rmask;
+ goto enqueue;
+}
+
+static int
+gred_requeue(struct sk_buff *skb, struct Qdisc* sch)
+{
+ struct gred_sched_data *q;
+ struct gred_sched *t= qdisc_priv(sch);
+ q= t->tab[(skb->tc_index&0xf)];
+/* error checking here -- probably unnecessary */
+ PSCHED_SET_PASTPERFECT(q->qidlestart);
+
+ __skb_queue_head(&sch->q, skb);
+ sch->qstats.backlog += skb->len;
+ sch->qstats.requeues++;
+ q->backlog += skb->len;
+ return 0;
+}
+
+static struct sk_buff *
+gred_dequeue(struct Qdisc* sch)
+{
+ struct sk_buff *skb;
+ struct gred_sched_data *q;
+ struct gred_sched *t= qdisc_priv(sch);
+
+ skb = __skb_dequeue(&sch->q);
+ if (skb) {
+ sch->qstats.backlog -= skb->len;
+ q= t->tab[(skb->tc_index&0xf)];
+ if (q) {
+ q->backlog -= skb->len;
+ if (!q->backlog && !t->eqp)
+ PSCHED_GET_TIME(q->qidlestart);
+ } else {
+ D2PRINTK("gred_dequeue: skb has bad tcindex %x\n",skb->tc_index&0xf);
+ }
+ return skb;
+ }
+
+ if (t->eqp) {
+ q= t->tab[t->def];
+ if (!q)
+ D2PRINTK("no default VQ set: Results will be "
+ "screwed up\n");
+ else
+ PSCHED_GET_TIME(q->qidlestart);
+ }
+
+ return NULL;
+}
+
+static unsigned int gred_drop(struct Qdisc* sch)
+{
+ struct sk_buff *skb;
+
+ struct gred_sched_data *q;
+ struct gred_sched *t= qdisc_priv(sch);
+
+ skb = __skb_dequeue_tail(&sch->q);
+ if (skb) {
+ unsigned int len = skb->len;
+ sch->qstats.backlog -= len;
+ sch->qstats.drops++;
+ q= t->tab[(skb->tc_index&0xf)];
+ if (q) {
+ q->backlog -= len;
+ q->other++;
+ if (!q->backlog && !t->eqp)
+ PSCHED_GET_TIME(q->qidlestart);
+ } else {
+ D2PRINTK("gred_dequeue: skb has bad tcindex %x\n",skb->tc_index&0xf);
+ }
+
+ kfree_skb(skb);
+ return len;
+ }
+
+ q=t->tab[t->def];
+ if (!q) {
+ D2PRINTK("no default VQ set: Results might be screwed up\n");
+ return 0;
+ }
+
+ PSCHED_GET_TIME(q->qidlestart);
+ return 0;
+
+}
+
+static void gred_reset(struct Qdisc* sch)
+{
+ int i;
+ struct gred_sched_data *q;
+ struct gred_sched *t= qdisc_priv(sch);
+
+ __skb_queue_purge(&sch->q);
+
+ sch->qstats.backlog = 0;
+
+ for (i=0;i<t->DPs;i++) {
+ q= t->tab[i];
+ if (!q)
+ continue;
+ PSCHED_SET_PASTPERFECT(q->qidlestart);
+ q->qave = 0;
+ q->qcount = -1;
+ q->backlog = 0;
+ q->other=0;
+ q->forced=0;
+ q->pdrop=0;
+ q->early=0;
+ }
+}
+
+static int gred_change(struct Qdisc *sch, struct rtattr *opt)
+{
+ struct gred_sched *table = qdisc_priv(sch);
+ struct gred_sched_data *q;
+ struct tc_gred_qopt *ctl;
+ struct tc_gred_sopt *sopt;
+ struct rtattr *tb[TCA_GRED_STAB];
+ struct rtattr *tb2[TCA_GRED_DPS];
+ int i;
+
+ if (opt == NULL || rtattr_parse_nested(tb, TCA_GRED_STAB, opt))
+ return -EINVAL;
+
+ if (tb[TCA_GRED_PARMS-1] == 0 && tb[TCA_GRED_STAB-1] == 0) {
+ rtattr_parse_nested(tb2, TCA_GRED_DPS, opt);
+
+ if (tb2[TCA_GRED_DPS-1] == 0)
+ return -EINVAL;
+
+ sopt = RTA_DATA(tb2[TCA_GRED_DPS-1]);
+ table->DPs=sopt->DPs;
+ table->def=sopt->def_DP;
+ table->grio=sopt->grio;
+ table->initd=0;
+ /* probably need to clear all the table DP entries as well */
+ return 0;
+ }
+
+
+ if (!table->DPs || tb[TCA_GRED_PARMS-1] == 0 || tb[TCA_GRED_STAB-1] == 0 ||
+ RTA_PAYLOAD(tb[TCA_GRED_PARMS-1]) < sizeof(*ctl) ||
+ RTA_PAYLOAD(tb[TCA_GRED_STAB-1]) < 256)
+ return -EINVAL;
+
+ ctl = RTA_DATA(tb[TCA_GRED_PARMS-1]);
+ if (ctl->DP > MAX_DPs-1 ) {
+ /* misbehaving is punished! Put in the default drop probability */
+ DPRINTK("\nGRED: DP %u not in the proper range fixed. New DP "
+ "set to default at %d\n",ctl->DP,table->def);
+ ctl->DP=table->def;
+ }
+
+ if (table->tab[ctl->DP] == NULL) {
+ table->tab[ctl->DP]=kmalloc(sizeof(struct gred_sched_data),
+ GFP_KERNEL);
+ if (NULL == table->tab[ctl->DP])
+ return -ENOMEM;
+ memset(table->tab[ctl->DP], 0, (sizeof(struct gred_sched_data)));
+ }
+ q= table->tab[ctl->DP];
+
+ if (table->grio) {
+ if (ctl->prio <=0) {
+ if (table->def && table->tab[table->def]) {
+ DPRINTK("\nGRED: DP %u does not have a prio"
+ "setting default to %d\n",ctl->DP,
+ table->tab[table->def]->prio);
+ q->prio=table->tab[table->def]->prio;
+ } else {
+ DPRINTK("\nGRED: DP %u does not have a prio"
+ " setting default to 8\n",ctl->DP);
+ q->prio=8;
+ }
+ } else {
+ q->prio=ctl->prio;
+ }
+ } else {
+ q->prio=8;
+ }
+
+
+ q->DP=ctl->DP;
+ q->Wlog = ctl->Wlog;
+ q->Plog = ctl->Plog;
+ q->limit = ctl->limit;
+ q->Scell_log = ctl->Scell_log;
+ q->Rmask = ctl->Plog < 32 ? ((1<<ctl->Plog) - 1) : ~0UL;
+ q->Scell_max = (255<<q->Scell_log);
+ q->qth_min = ctl->qth_min<<ctl->Wlog;
+ q->qth_max = ctl->qth_max<<ctl->Wlog;
+ q->qave=0;
+ q->backlog=0;
+ q->qcount = -1;
+ q->other=0;
+ q->forced=0;
+ q->pdrop=0;
+ q->early=0;
+
+ PSCHED_SET_PASTPERFECT(q->qidlestart);
+ memcpy(q->Stab, RTA_DATA(tb[TCA_GRED_STAB-1]), 256);
+
+ if ( table->initd && table->grio) {
+ /* this looks ugly but it's not in the fast path */
+ for (i=0;i<table->DPs;i++) {
+ if ((!table->tab[i]) || (i==q->DP) )
+ continue;
+ if (table->tab[i]->prio == q->prio ){
+ /* WRED mode detected */
+ table->eqp=1;
+ break;
+ }
+ }
+ }
+
+ if (!table->initd) {
+ table->initd=1;
+ /*
+ the first entry also goes into the default until
+ over-written
+ */
+
+ if (table->tab[table->def] == NULL) {
+ table->tab[table->def]=
+ kmalloc(sizeof(struct gred_sched_data), GFP_KERNEL);
+ if (NULL == table->tab[table->def])
+ return -ENOMEM;
+
+ memset(table->tab[table->def], 0,
+ (sizeof(struct gred_sched_data)));
+ }
+ q= table->tab[table->def];
+ q->DP=table->def;
+ q->Wlog = ctl->Wlog;
+ q->Plog = ctl->Plog;
+ q->limit = ctl->limit;
+ q->Scell_log = ctl->Scell_log;
+ q->Rmask = ctl->Plog < 32 ? ((1<<ctl->Plog) - 1) : ~0UL;
+ q->Scell_max = (255<<q->Scell_log);
+ q->qth_min = ctl->qth_min<<ctl->Wlog;
+ q->qth_max = ctl->qth_max<<ctl->Wlog;
+
+ if (table->grio)
+ q->prio=table->tab[ctl->DP]->prio;
+ else
+ q->prio=8;
+
+ q->qcount = -1;
+ PSCHED_SET_PASTPERFECT(q->qidlestart);
+ memcpy(q->Stab, RTA_DATA(tb[TCA_GRED_STAB-1]), 256);
+ }
+ return 0;
+
+}
+
+static int gred_init(struct Qdisc *sch, struct rtattr *opt)
+{
+ struct gred_sched *table = qdisc_priv(sch);
+ struct tc_gred_sopt *sopt;
+ struct rtattr *tb[TCA_GRED_STAB];
+ struct rtattr *tb2[TCA_GRED_DPS];
+
+ if (opt == NULL || rtattr_parse_nested(tb, TCA_GRED_STAB, opt))
+ return -EINVAL;
+
+ if (tb[TCA_GRED_PARMS-1] == 0 && tb[TCA_GRED_STAB-1] == 0) {
+ rtattr_parse_nested(tb2, TCA_GRED_DPS, opt);
+
+ if (tb2[TCA_GRED_DPS-1] == 0)
+ return -EINVAL;
+
+ sopt = RTA_DATA(tb2[TCA_GRED_DPS-1]);
+ table->DPs=sopt->DPs;
+ table->def=sopt->def_DP;
+ table->grio=sopt->grio;
+ table->initd=0;
+ return 0;
+ }
+
+ DPRINTK("\n GRED_INIT error!\n");
+ return -EINVAL;
+}
+
+static int gred_dump(struct Qdisc *sch, struct sk_buff *skb)
+{
+ unsigned long qave;
+ struct rtattr *rta;
+ struct tc_gred_qopt *opt = NULL ;
+ struct tc_gred_qopt *dst;
+ struct gred_sched *table = qdisc_priv(sch);
+ struct gred_sched_data *q;
+ int i;
+ unsigned char *b = skb->tail;
+
+ rta = (struct rtattr*)b;
+ RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
+
+ opt=kmalloc(sizeof(struct tc_gred_qopt)*MAX_DPs, GFP_KERNEL);
+
+ if (opt == NULL) {
+ DPRINTK("gred_dump:failed to malloc for %Zd\n",
+ sizeof(struct tc_gred_qopt)*MAX_DPs);
+ goto rtattr_failure;
+ }
+
+ memset(opt, 0, (sizeof(struct tc_gred_qopt))*table->DPs);
+
+ if (!table->initd) {
+ DPRINTK("NO GRED Queues setup!\n");
+ }
+
+ for (i=0;i<MAX_DPs;i++) {
+ dst= &opt[i];
+ q= table->tab[i];
+
+ if (!q) {
+ /* hack -- fix at some point with proper message
+ This is how we indicate to tc that there is no VQ
+ at this DP */
+
+ dst->DP=MAX_DPs+i;
+ continue;
+ }
+
+ dst->limit=q->limit;
+ dst->qth_min=q->qth_min>>q->Wlog;
+ dst->qth_max=q->qth_max>>q->Wlog;
+ dst->DP=q->DP;
+ dst->backlog=q->backlog;
+ if (q->qave) {
+ if (table->eqp && table->grio) {
+ q->qidlestart=table->tab[table->def]->qidlestart;
+ q->qave=table->tab[table->def]->qave;
+ }
+ if (!PSCHED_IS_PASTPERFECT(q->qidlestart)) {
+ long idle;
+ psched_time_t now;
+ PSCHED_GET_TIME(now);
+ idle = PSCHED_TDIFF_SAFE(now, q->qidlestart, q->Scell_max);
+ qave = q->qave >> q->Stab[(idle>>q->Scell_log)&0xFF];
+ dst->qave = qave >> q->Wlog;
+
+ } else {
+ dst->qave = q->qave >> q->Wlog;
+ }
+ } else {
+ dst->qave = 0;
+ }
+
+
+ dst->Wlog = q->Wlog;
+ dst->Plog = q->Plog;
+ dst->Scell_log = q->Scell_log;
+ dst->other = q->other;
+ dst->forced = q->forced;
+ dst->early = q->early;
+ dst->pdrop = q->pdrop;
+ dst->prio = q->prio;
+ dst->packets=q->packetsin;
+ dst->bytesin=q->bytesin;
+ }
+
+ RTA_PUT(skb, TCA_GRED_PARMS, sizeof(struct tc_gred_qopt)*MAX_DPs, opt);
+ rta->rta_len = skb->tail - b;
+
+ kfree(opt);
+ return skb->len;
+
+rtattr_failure:
+ if (opt)
+ kfree(opt);
+ DPRINTK("gred_dump: FAILURE!!!!\n");
+
+/* also free the opt struct here */
+ skb_trim(skb, b - skb->data);
+ return -1;
+}
+
+static void gred_destroy(struct Qdisc *sch)
+{
+ struct gred_sched *table = qdisc_priv(sch);
+ int i;
+
+ for (i = 0;i < table->DPs; i++) {
+ if (table->tab[i])
+ kfree(table->tab[i]);
+ }
+}
+
+static struct Qdisc_ops gred_qdisc_ops = {
+ .next = NULL,
+ .cl_ops = NULL,
+ .id = "gred",
+ .priv_size = sizeof(struct gred_sched),
+ .enqueue = gred_enqueue,
+ .dequeue = gred_dequeue,
+ .requeue = gred_requeue,
+ .drop = gred_drop,
+ .init = gred_init,
+ .reset = gred_reset,
+ .destroy = gred_destroy,
+ .change = gred_change,
+ .dump = gred_dump,
+ .owner = THIS_MODULE,
+};
+
+static int __init gred_module_init(void)
+{
+ return register_qdisc(&gred_qdisc_ops);
+}
+static void __exit gred_module_exit(void)
+{
+ unregister_qdisc(&gred_qdisc_ops);
+}
+module_init(gred_module_init)
+module_exit(gred_module_exit)
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.0.4) at 2024-11-05 12:50:03 +0000