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DEFINITIONS
This source file includes following definitions.
- prio_classify
- prio_enqueue
- prio_requeue
- prio_dequeue
- prio_drop
- prio_reset
- prio_destroy
- prio_tune
- prio_init
- prio_dump
- prio_graft
- prio_leaf
- prio_get
- prio_bind
- prio_put
- prio_change
- prio_delete
- prio_dump_class
- prio_dump_class_stats
- prio_walk
- prio_find_tcf
- prio_module_init
- prio_module_exit
/*
* net/sched/sch_prio.c Simple 3-band priority "scheduler".
*
* 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: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
* Fixes: 19990609: J Hadi Salim <hadi@nortelnetworks.com>:
* Init -- EINVAL when opt undefined
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
struct prio_sched_data
{
int bands;
struct tcf_proto *filter_list;
u8 prio2band[TC_PRIO_MAX+1];
struct Qdisc *queues[TCQ_PRIO_BANDS];
};
static struct Qdisc *
prio_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
{
struct prio_sched_data *q = qdisc_priv(sch);
u32 band = skb->priority;
struct tcf_result res;
int err;
*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
if (TC_H_MAJ(skb->priority) != sch->handle) {
err = tc_classify(skb, q->filter_list, &res);
#ifdef CONFIG_NET_CLS_ACT
switch (err) {
case TC_ACT_STOLEN:
case TC_ACT_QUEUED:
*qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
case TC_ACT_SHOT:
return NULL;
}
#endif
if (!q->filter_list || err < 0) {
if (TC_H_MAJ(band))
band = 0;
return q->queues[q->prio2band[band&TC_PRIO_MAX]];
}
band = res.classid;
}
band = TC_H_MIN(band) - 1;
if (band >= q->bands)
return q->queues[q->prio2band[0]];
return q->queues[band];
}
static int
prio_enqueue(struct sk_buff *skb, struct Qdisc *sch)
{
struct Qdisc *qdisc;
int ret;
qdisc = prio_classify(skb, sch, &ret);
#ifdef CONFIG_NET_CLS_ACT
if (qdisc == NULL) {
if (ret & __NET_XMIT_BYPASS)
sch->qstats.drops++;
kfree_skb(skb);
return ret;
}
#endif
ret = qdisc_enqueue(skb, qdisc);
if (ret == NET_XMIT_SUCCESS) {
sch->bstats.bytes += qdisc_pkt_len(skb);
sch->bstats.packets++;
sch->q.qlen++;
return NET_XMIT_SUCCESS;
}
if (net_xmit_drop_count(ret))
sch->qstats.drops++;
return ret;
}
static int
prio_requeue(struct sk_buff *skb, struct Qdisc* sch)
{
struct Qdisc *qdisc;
int ret;
qdisc = prio_classify(skb, sch, &ret);
#ifdef CONFIG_NET_CLS_ACT
if (qdisc == NULL) {
if (ret & __NET_XMIT_BYPASS)
sch->qstats.drops++;
kfree_skb(skb);
return ret;
}
#endif
if ((ret = qdisc->ops->requeue(skb, qdisc)) == NET_XMIT_SUCCESS) {
sch->q.qlen++;
sch->qstats.requeues++;
return NET_XMIT_SUCCESS;
}
if (net_xmit_drop_count(ret))
sch->qstats.drops++;
return ret;
}
static struct sk_buff *prio_dequeue(struct Qdisc* sch)
{
struct prio_sched_data *q = qdisc_priv(sch);
int prio;
for (prio = 0; prio < q->bands; prio++) {
struct Qdisc *qdisc = q->queues[prio];
struct sk_buff *skb = qdisc->dequeue(qdisc);
if (skb) {
sch->q.qlen--;
return skb;
}
}
return NULL;
}
static unsigned int prio_drop(struct Qdisc* sch)
{
struct prio_sched_data *q = qdisc_priv(sch);
int prio;
unsigned int len;
struct Qdisc *qdisc;
for (prio = q->bands-1; prio >= 0; prio--) {
qdisc = q->queues[prio];
if (qdisc->ops->drop && (len = qdisc->ops->drop(qdisc)) != 0) {
sch->q.qlen--;
return len;
}
}
return 0;
}
static void
prio_reset(struct Qdisc* sch)
{
int prio;
struct prio_sched_data *q = qdisc_priv(sch);
for (prio=0; prio<q->bands; prio++)
qdisc_reset(q->queues[prio]);
sch->q.qlen = 0;
}
static void
prio_destroy(struct Qdisc* sch)
{
int prio;
struct prio_sched_data *q = qdisc_priv(sch);
tcf_destroy_chain(&q->filter_list);
for (prio=0; prio<q->bands; prio++)
qdisc_destroy(q->queues[prio]);
}
static int prio_tune(struct Qdisc *sch, struct nlattr *opt)
{
struct prio_sched_data *q = qdisc_priv(sch);
struct tc_prio_qopt *qopt;
int i;
if (nla_len(opt) < sizeof(*qopt))
return -EINVAL;
qopt = nla_data(opt);
if (qopt->bands > TCQ_PRIO_BANDS || qopt->bands < 2)
return -EINVAL;
for (i=0; i<=TC_PRIO_MAX; i++) {
if (qopt->priomap[i] >= qopt->bands)
return -EINVAL;
}
sch_tree_lock(sch);
q->bands = qopt->bands;
memcpy(q->prio2band, qopt->priomap, TC_PRIO_MAX+1);
for (i=q->bands; i<TCQ_PRIO_BANDS; i++) {
struct Qdisc *child = xchg(&q->queues[i], &noop_qdisc);
if (child != &noop_qdisc) {
qdisc_tree_decrease_qlen(child, child->q.qlen);
qdisc_destroy(child);
}
}
sch_tree_unlock(sch);
for (i=0; i<q->bands; i++) {
if (q->queues[i] == &noop_qdisc) {
struct Qdisc *child;
child = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
&pfifo_qdisc_ops,
TC_H_MAKE(sch->handle, i + 1));
if (child) {
sch_tree_lock(sch);
child = xchg(&q->queues[i], child);
if (child != &noop_qdisc) {
qdisc_tree_decrease_qlen(child,
child->q.qlen);
qdisc_destroy(child);
}
sch_tree_unlock(sch);
}
}
}
return 0;
}
static int prio_init(struct Qdisc *sch, struct nlattr *opt)
{
struct prio_sched_data *q = qdisc_priv(sch);
int i;
for (i=0; i<TCQ_PRIO_BANDS; i++)
q->queues[i] = &noop_qdisc;
if (opt == NULL) {
return -EINVAL;
} else {
int err;
if ((err= prio_tune(sch, opt)) != 0)
return err;
}
return 0;
}
static int prio_dump(struct Qdisc *sch, struct sk_buff *skb)
{
struct prio_sched_data *q = qdisc_priv(sch);
unsigned char *b = skb_tail_pointer(skb);
struct tc_prio_qopt opt;
opt.bands = q->bands;
memcpy(&opt.priomap, q->prio2band, TC_PRIO_MAX+1);
NLA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
return skb->len;
nla_put_failure:
nlmsg_trim(skb, b);
return -1;
}
static int prio_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
struct Qdisc **old)
{
struct prio_sched_data *q = qdisc_priv(sch);
unsigned long band = arg - 1;
if (band >= q->bands)
return -EINVAL;
if (new == NULL)
new = &noop_qdisc;
sch_tree_lock(sch);
*old = q->queues[band];
q->queues[band] = new;
qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
qdisc_reset(*old);
sch_tree_unlock(sch);
return 0;
}
static struct Qdisc *
prio_leaf(struct Qdisc *sch, unsigned long arg)
{
struct prio_sched_data *q = qdisc_priv(sch);
unsigned long band = arg - 1;
if (band >= q->bands)
return NULL;
return q->queues[band];
}
static unsigned long prio_get(struct Qdisc *sch, u32 classid)
{
struct prio_sched_data *q = qdisc_priv(sch);
unsigned long band = TC_H_MIN(classid);
if (band - 1 >= q->bands)
return 0;
return band;
}
static unsigned long prio_bind(struct Qdisc *sch, unsigned long parent, u32 classid)
{
return prio_get(sch, classid);
}
static void prio_put(struct Qdisc *q, unsigned long cl)
{
return;
}
static int prio_change(struct Qdisc *sch, u32 handle, u32 parent, struct nlattr **tca, unsigned long *arg)
{
unsigned long cl = *arg;
struct prio_sched_data *q = qdisc_priv(sch);
if (cl - 1 > q->bands)
return -ENOENT;
return 0;
}
static int prio_delete(struct Qdisc *sch, unsigned long cl)
{
struct prio_sched_data *q = qdisc_priv(sch);
if (cl - 1 > q->bands)
return -ENOENT;
return 0;
}
static int prio_dump_class(struct Qdisc *sch, unsigned long cl, struct sk_buff *skb,
struct tcmsg *tcm)
{
struct prio_sched_data *q = qdisc_priv(sch);
if (cl - 1 > q->bands)
return -ENOENT;
tcm->tcm_handle |= TC_H_MIN(cl);
if (q->queues[cl-1])
tcm->tcm_info = q->queues[cl-1]->handle;
return 0;
}
static int prio_dump_class_stats(struct Qdisc *sch, unsigned long cl,
struct gnet_dump *d)
{
struct prio_sched_data *q = qdisc_priv(sch);
struct Qdisc *cl_q;
cl_q = q->queues[cl - 1];
if (gnet_stats_copy_basic(d, &cl_q->bstats) < 0 ||
gnet_stats_copy_queue(d, &cl_q->qstats) < 0)
return -1;
return 0;
}
static void prio_walk(struct Qdisc *sch, struct qdisc_walker *arg)
{
struct prio_sched_data *q = qdisc_priv(sch);
int prio;
if (arg->stop)
return;
for (prio = 0; prio < q->bands; prio++) {
if (arg->count < arg->skip) {
arg->count++;
continue;
}
if (arg->fn(sch, prio+1, arg) < 0) {
arg->stop = 1;
break;
}
arg->count++;
}
}
static struct tcf_proto ** prio_find_tcf(struct Qdisc *sch, unsigned long cl)
{
struct prio_sched_data *q = qdisc_priv(sch);
if (cl)
return NULL;
return &q->filter_list;
}
static const struct Qdisc_class_ops prio_class_ops = {
.graft = prio_graft,
.leaf = prio_leaf,
.get = prio_get,
.put = prio_put,
.change = prio_change,
.delete = prio_delete,
.walk = prio_walk,
.tcf_chain = prio_find_tcf,
.bind_tcf = prio_bind,
.unbind_tcf = prio_put,
.dump = prio_dump_class,
.dump_stats = prio_dump_class_stats,
};
static struct Qdisc_ops prio_qdisc_ops __read_mostly = {
.next = NULL,
.cl_ops = &prio_class_ops,
.id = "prio",
.priv_size = sizeof(struct prio_sched_data),
.enqueue = prio_enqueue,
.dequeue = prio_dequeue,
.requeue = prio_requeue,
.drop = prio_drop,
.init = prio_init,
.reset = prio_reset,
.destroy = prio_destroy,
.change = prio_tune,
.dump = prio_dump,
.owner = THIS_MODULE,
};
static int __init prio_module_init(void)
{
return register_qdisc(&prio_qdisc_ops);
}
static void __exit prio_module_exit(void)
{
unregister_qdisc(&prio_qdisc_ops);
}
module_init(prio_module_init)
module_exit(prio_module_exit)
MODULE_LICENSE("GPL");