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DEFINITIONS
This source file includes following definitions.
- multiq_classify
- multiq_enqueue
- multiq_requeue
- multiq_dequeue
- multiq_drop
- multiq_reset
- multiq_destroy
- multiq_tune
- multiq_init
- multiq_dump
- multiq_graft
- multiq_leaf
- multiq_get
- multiq_bind
- multiq_put
- multiq_change
- multiq_delete
- multiq_dump_class
- multiq_dump_class_stats
- multiq_walk
- multiq_find_tcf
- multiq_module_init
- multiq_module_exit
/*
* Copyright (c) 2008, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc., 59 Temple
* Place - Suite 330, Boston, MA 02111-1307 USA.
*
* Author: Alexander Duyck <alexander.h.duyck@intel.com>
*/
#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 multiq_sched_data {
u16 bands;
u16 max_bands;
u16 curband;
struct tcf_proto *filter_list;
struct Qdisc **queues;
};
static struct Qdisc *
multiq_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
{
struct multiq_sched_data *q = qdisc_priv(sch);
u32 band;
struct tcf_result res;
int err;
*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
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
band = skb_get_queue_mapping(skb);
if (band >= q->bands)
return q->queues[0];
return q->queues[band];
}
static int
multiq_enqueue(struct sk_buff *skb, struct Qdisc *sch)
{
struct Qdisc *qdisc;
int ret;
qdisc = multiq_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
multiq_requeue(struct sk_buff *skb, struct Qdisc *sch)
{
struct Qdisc *qdisc;
struct multiq_sched_data *q = qdisc_priv(sch);
int ret;
qdisc = multiq_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->ops->requeue(skb, qdisc);
if (ret == NET_XMIT_SUCCESS) {
sch->q.qlen++;
sch->qstats.requeues++;
if (q->curband)
q->curband--;
else
q->curband = q->bands - 1;
return NET_XMIT_SUCCESS;
}
if (net_xmit_drop_count(ret))
sch->qstats.drops++;
return ret;
}
static struct sk_buff *multiq_dequeue(struct Qdisc *sch)
{
struct multiq_sched_data *q = qdisc_priv(sch);
struct Qdisc *qdisc;
struct sk_buff *skb;
int band;
for (band = 0; band < q->bands; band++) {
/* cycle through bands to ensure fairness */
q->curband++;
if (q->curband >= q->bands)
q->curband = 0;
/* Check that target subqueue is available before
* pulling an skb to avoid excessive requeues
*/
if (!__netif_subqueue_stopped(qdisc_dev(sch), q->curband)) {
qdisc = q->queues[q->curband];
skb = qdisc->dequeue(qdisc);
if (skb) {
sch->q.qlen--;
return skb;
}
}
}
return NULL;
}
static unsigned int multiq_drop(struct Qdisc *sch)
{
struct multiq_sched_data *q = qdisc_priv(sch);
int band;
unsigned int len;
struct Qdisc *qdisc;
for (band = q->bands-1; band >= 0; band--) {
qdisc = q->queues[band];
if (qdisc->ops->drop) {
len = qdisc->ops->drop(qdisc);
if (len != 0) {
sch->q.qlen--;
return len;
}
}
}
return 0;
}
static void
multiq_reset(struct Qdisc *sch)
{
u16 band;
struct multiq_sched_data *q = qdisc_priv(sch);
for (band = 0; band < q->bands; band++)
qdisc_reset(q->queues[band]);
sch->q.qlen = 0;
q->curband = 0;
}
static void
multiq_destroy(struct Qdisc *sch)
{
int band;
struct multiq_sched_data *q = qdisc_priv(sch);
tcf_destroy_chain(&q->filter_list);
for (band = 0; band < q->bands; band++)
qdisc_destroy(q->queues[band]);
kfree(q->queues);
}
static int multiq_tune(struct Qdisc *sch, struct nlattr *opt)
{
struct multiq_sched_data *q = qdisc_priv(sch);
struct tc_multiq_qopt *qopt;
int i;
if (!netif_is_multiqueue(qdisc_dev(sch)))
return -EINVAL;
if (nla_len(opt) < sizeof(*qopt))
return -EINVAL;
qopt = nla_data(opt);
qopt->bands = qdisc_dev(sch)->real_num_tx_queues;
sch_tree_lock(sch);
q->bands = qopt->bands;
for (i = q->bands; i < q->max_bands; i++) {
if (q->queues[i] != &noop_qdisc) {
struct Qdisc *child = xchg(&q->queues[i], &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 multiq_init(struct Qdisc *sch, struct nlattr *opt)
{
struct multiq_sched_data *q = qdisc_priv(sch);
int i, err;
q->queues = NULL;
if (opt == NULL)
return -EINVAL;
q->max_bands = qdisc_dev(sch)->num_tx_queues;
q->queues = kcalloc(q->max_bands, sizeof(struct Qdisc *), GFP_KERNEL);
if (!q->queues)
return -ENOBUFS;
for (i = 0; i < q->max_bands; i++)
q->queues[i] = &noop_qdisc;
err = multiq_tune(sch,opt);
if (err)
kfree(q->queues);
return err;
}
static int multiq_dump(struct Qdisc *sch, struct sk_buff *skb)
{
struct multiq_sched_data *q = qdisc_priv(sch);
unsigned char *b = skb_tail_pointer(skb);
struct tc_multiq_qopt opt;
opt.bands = q->bands;
opt.max_bands = q->max_bands;
NLA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
return skb->len;
nla_put_failure:
nlmsg_trim(skb, b);
return -1;
}
static int multiq_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
struct Qdisc **old)
{
struct multiq_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 *
multiq_leaf(struct Qdisc *sch, unsigned long arg)
{
struct multiq_sched_data *q = qdisc_priv(sch);
unsigned long band = arg - 1;
if (band >= q->bands)
return NULL;
return q->queues[band];
}
static unsigned long multiq_get(struct Qdisc *sch, u32 classid)
{
struct multiq_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 multiq_bind(struct Qdisc *sch, unsigned long parent,
u32 classid)
{
return multiq_get(sch, classid);
}
static void multiq_put(struct Qdisc *q, unsigned long cl)
{
return;
}
static int multiq_change(struct Qdisc *sch, u32 handle, u32 parent,
struct nlattr **tca, unsigned long *arg)
{
unsigned long cl = *arg;
struct multiq_sched_data *q = qdisc_priv(sch);
if (cl - 1 > q->bands)
return -ENOENT;
return 0;
}
static int multiq_delete(struct Qdisc *sch, unsigned long cl)
{
struct multiq_sched_data *q = qdisc_priv(sch);
if (cl - 1 > q->bands)
return -ENOENT;
return 0;
}
static int multiq_dump_class(struct Qdisc *sch, unsigned long cl,
struct sk_buff *skb, struct tcmsg *tcm)
{
struct multiq_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 multiq_dump_class_stats(struct Qdisc *sch, unsigned long cl,
struct gnet_dump *d)
{
struct multiq_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 multiq_walk(struct Qdisc *sch, struct qdisc_walker *arg)
{
struct multiq_sched_data *q = qdisc_priv(sch);
int band;
if (arg->stop)
return;
for (band = 0; band < q->bands; band++) {
if (arg->count < arg->skip) {
arg->count++;
continue;
}
if (arg->fn(sch, band+1, arg) < 0) {
arg->stop = 1;
break;
}
arg->count++;
}
}
static struct tcf_proto **multiq_find_tcf(struct Qdisc *sch, unsigned long cl)
{
struct multiq_sched_data *q = qdisc_priv(sch);
if (cl)
return NULL;
return &q->filter_list;
}
static const struct Qdisc_class_ops multiq_class_ops = {
.graft = multiq_graft,
.leaf = multiq_leaf,
.get = multiq_get,
.put = multiq_put,
.change = multiq_change,
.delete = multiq_delete,
.walk = multiq_walk,
.tcf_chain = multiq_find_tcf,
.bind_tcf = multiq_bind,
.unbind_tcf = multiq_put,
.dump = multiq_dump_class,
.dump_stats = multiq_dump_class_stats,
};
static struct Qdisc_ops multiq_qdisc_ops __read_mostly = {
.next = NULL,
.cl_ops = &multiq_class_ops,
.id = "multiq",
.priv_size = sizeof(struct multiq_sched_data),
.enqueue = multiq_enqueue,
.dequeue = multiq_dequeue,
.requeue = multiq_requeue,
.drop = multiq_drop,
.init = multiq_init,
.reset = multiq_reset,
.destroy = multiq_destroy,
.change = multiq_tune,
.dump = multiq_dump,
.owner = THIS_MODULE,
};
static int __init multiq_module_init(void)
{
return register_qdisc(&multiq_qdisc_ops);
}
static void __exit multiq_module_exit(void)
{
unregister_qdisc(&multiq_qdisc_ops);
}
module_init(multiq_module_init)
module_exit(multiq_module_exit)
MODULE_LICENSE("GPL");