blob: 626170d568cecd51a74911e999304e8d7e7eb707 [file] [log] [blame]
/*
* net/sched/sch_mqprio.c
*
* Copyright (c) 2010 John Fastabend <john.r.fastabend@intel.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*/
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <linux/module.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <net/sch_generic.h>
struct mqprio_sched {
struct Qdisc **qdiscs;
int hw_owned;
};
static void mqprio_destroy(struct Qdisc *sch)
{
struct net_device *dev = qdisc_dev(sch);
struct mqprio_sched *priv = qdisc_priv(sch);
unsigned int ntx;
if (priv->qdiscs) {
for (ntx = 0;
ntx < dev->num_tx_queues && priv->qdiscs[ntx];
ntx++)
qdisc_destroy(priv->qdiscs[ntx]);
kfree(priv->qdiscs);
}
if (priv->hw_owned && dev->netdev_ops->ndo_setup_tc)
dev->netdev_ops->ndo_setup_tc(dev, 0);
else
netdev_set_num_tc(dev, 0);
}
static int mqprio_parse_opt(struct net_device *dev, struct tc_mqprio_qopt *qopt)
{
int i, j;
/* Verify num_tc is not out of max range */
if (qopt->num_tc > TC_MAX_QUEUE)
return -EINVAL;
/* Verify priority mapping uses valid tcs */
for (i = 0; i < TC_BITMASK + 1; i++) {
if (qopt->prio_tc_map[i] >= qopt->num_tc)
return -EINVAL;
}
/* net_device does not support requested operation */
if (qopt->hw && !dev->netdev_ops->ndo_setup_tc)
return -EINVAL;
/* if hw owned qcount and qoffset are taken from LLD so
* no reason to verify them here
*/
if (qopt->hw)
return 0;
for (i = 0; i < qopt->num_tc; i++) {
unsigned int last = qopt->offset[i] + qopt->count[i];
/* Verify the queue count is in tx range being equal to the
* real_num_tx_queues indicates the last queue is in use.
*/
if (qopt->offset[i] >= dev->real_num_tx_queues ||
!qopt->count[i] ||
last > dev->real_num_tx_queues)
return -EINVAL;
/* Verify that the offset and counts do not overlap */
for (j = i + 1; j < qopt->num_tc; j++) {
if (last > qopt->offset[j])
return -EINVAL;
}
}
return 0;
}
static int mqprio_init(struct Qdisc *sch, struct nlattr *opt)
{
struct net_device *dev = qdisc_dev(sch);
struct mqprio_sched *priv = qdisc_priv(sch);
struct netdev_queue *dev_queue;
struct Qdisc *qdisc;
int i, err = -EOPNOTSUPP;
struct tc_mqprio_qopt *qopt = NULL;
BUILD_BUG_ON(TC_MAX_QUEUE != TC_QOPT_MAX_QUEUE);
BUILD_BUG_ON(TC_BITMASK != TC_QOPT_BITMASK);
if (sch->parent != TC_H_ROOT)
return -EOPNOTSUPP;
if (!netif_is_multiqueue(dev))
return -EOPNOTSUPP;
if (!opt || nla_len(opt) < sizeof(*qopt))
return -EINVAL;
qopt = nla_data(opt);
if (mqprio_parse_opt(dev, qopt))
return -EINVAL;
/* pre-allocate qdisc, attachment can't fail */
priv->qdiscs = kcalloc(dev->num_tx_queues, sizeof(priv->qdiscs[0]),
GFP_KERNEL);
if (!priv->qdiscs)
return -ENOMEM;
for (i = 0; i < dev->num_tx_queues; i++) {
dev_queue = netdev_get_tx_queue(dev, i);
qdisc = qdisc_create_dflt(dev_queue, default_qdisc_ops,
TC_H_MAKE(TC_H_MAJ(sch->handle),
TC_H_MIN(i + 1)));
if (!qdisc)
return -ENOMEM;
priv->qdiscs[i] = qdisc;
qdisc->flags |= TCQ_F_ONETXQUEUE;
}
/* If the mqprio options indicate that hardware should own
* the queue mapping then run ndo_setup_tc otherwise use the
* supplied and verified mapping
*/
if (qopt->hw) {
priv->hw_owned = 1;
err = dev->netdev_ops->ndo_setup_tc(dev, qopt->num_tc);
if (err)
return err;
} else {
netdev_set_num_tc(dev, qopt->num_tc);
for (i = 0; i < qopt->num_tc; i++)
netdev_set_tc_queue(dev, i,
qopt->count[i], qopt->offset[i]);
}
/* Always use supplied priority mappings */
for (i = 0; i < TC_BITMASK + 1; i++)
netdev_set_prio_tc_map(dev, i, qopt->prio_tc_map[i]);
sch->flags |= TCQ_F_MQROOT;
return 0;
}
static void mqprio_attach(struct Qdisc *sch)
{
struct net_device *dev = qdisc_dev(sch);
struct mqprio_sched *priv = qdisc_priv(sch);
struct Qdisc *qdisc, *old;
unsigned int ntx;
/* Attach underlying qdisc */
for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
qdisc = priv->qdiscs[ntx];
old = dev_graft_qdisc(qdisc->dev_queue, qdisc);
if (old)
qdisc_destroy(old);
if (ntx < dev->real_num_tx_queues)
qdisc_list_add(qdisc);
}
kfree(priv->qdiscs);
priv->qdiscs = NULL;
}
static struct netdev_queue *mqprio_queue_get(struct Qdisc *sch,
unsigned long cl)
{
struct net_device *dev = qdisc_dev(sch);
unsigned long ntx = cl - 1 - netdev_get_num_tc(dev);
if (ntx >= dev->num_tx_queues)
return NULL;
return netdev_get_tx_queue(dev, ntx);
}
static int mqprio_graft(struct Qdisc *sch, unsigned long cl, struct Qdisc *new,
struct Qdisc **old)
{
struct net_device *dev = qdisc_dev(sch);
struct netdev_queue *dev_queue = mqprio_queue_get(sch, cl);
if (!dev_queue)
return -EINVAL;
if (dev->flags & IFF_UP)
dev_deactivate(dev);
*old = dev_graft_qdisc(dev_queue, new);
if (new)
new->flags |= TCQ_F_ONETXQUEUE;
if (dev->flags & IFF_UP)
dev_activate(dev);
return 0;
}
static int mqprio_dump(struct Qdisc *sch, struct sk_buff *skb)
{
struct net_device *dev = qdisc_dev(sch);
struct mqprio_sched *priv = qdisc_priv(sch);
unsigned char *b = skb_tail_pointer(skb);
struct tc_mqprio_qopt opt = { 0 };
struct Qdisc *qdisc;
unsigned int i;
sch->q.qlen = 0;
memset(&sch->bstats, 0, sizeof(sch->bstats));
memset(&sch->qstats, 0, sizeof(sch->qstats));
for (i = 0; i < dev->num_tx_queues; i++) {
qdisc = netdev_get_tx_queue(dev, i)->qdisc;
spin_lock_bh(qdisc_lock(qdisc));
sch->q.qlen += qdisc->q.qlen;
sch->bstats.bytes += qdisc->bstats.bytes;
sch->bstats.packets += qdisc->bstats.packets;
sch->qstats.qlen += qdisc->qstats.qlen;
sch->qstats.backlog += qdisc->qstats.backlog;
sch->qstats.drops += qdisc->qstats.drops;
sch->qstats.requeues += qdisc->qstats.requeues;
sch->qstats.overlimits += qdisc->qstats.overlimits;
spin_unlock_bh(qdisc_lock(qdisc));
}
opt.num_tc = netdev_get_num_tc(dev);
memcpy(opt.prio_tc_map, dev->prio_tc_map, sizeof(opt.prio_tc_map));
opt.hw = priv->hw_owned;
for (i = 0; i < netdev_get_num_tc(dev); i++) {
opt.count[i] = dev->tc_to_txq[i].count;
opt.offset[i] = dev->tc_to_txq[i].offset;
}
if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt))
goto nla_put_failure;
return skb->len;
nla_put_failure:
nlmsg_trim(skb, b);
return -1;
}
static struct Qdisc *mqprio_leaf(struct Qdisc *sch, unsigned long cl)
{
struct netdev_queue *dev_queue = mqprio_queue_get(sch, cl);
if (!dev_queue)
return NULL;
return dev_queue->qdisc_sleeping;
}
static unsigned long mqprio_get(struct Qdisc *sch, u32 classid)
{
struct net_device *dev = qdisc_dev(sch);
unsigned int ntx = TC_H_MIN(classid);
if (ntx > dev->num_tx_queues + netdev_get_num_tc(dev))
return 0;
return ntx;
}
static void mqprio_put(struct Qdisc *sch, unsigned long cl)
{
}
static int mqprio_dump_class(struct Qdisc *sch, unsigned long cl,
struct sk_buff *skb, struct tcmsg *tcm)
{
struct net_device *dev = qdisc_dev(sch);
if (cl <= netdev_get_num_tc(dev)) {
tcm->tcm_parent = TC_H_ROOT;
tcm->tcm_info = 0;
} else {
int i;
struct netdev_queue *dev_queue;
dev_queue = mqprio_queue_get(sch, cl);
tcm->tcm_parent = 0;
for (i = 0; i < netdev_get_num_tc(dev); i++) {
struct netdev_tc_txq tc = dev->tc_to_txq[i];
int q_idx = cl - netdev_get_num_tc(dev);
if (q_idx > tc.offset &&
q_idx <= tc.offset + tc.count) {
tcm->tcm_parent =
TC_H_MAKE(TC_H_MAJ(sch->handle),
TC_H_MIN(i + 1));
break;
}
}
tcm->tcm_info = dev_queue->qdisc_sleeping->handle;
}
tcm->tcm_handle |= TC_H_MIN(cl);
return 0;
}
static int mqprio_dump_class_stats(struct Qdisc *sch, unsigned long cl,
struct gnet_dump *d)
__releases(d->lock)
__acquires(d->lock)
{
struct net_device *dev = qdisc_dev(sch);
if (cl <= netdev_get_num_tc(dev)) {
int i;
struct Qdisc *qdisc;
struct gnet_stats_queue qstats = {0};
struct gnet_stats_basic_packed bstats = {0};
struct netdev_tc_txq tc = dev->tc_to_txq[cl - 1];
/* Drop lock here it will be reclaimed before touching
* statistics this is required because the d->lock we
* hold here is the look on dev_queue->qdisc_sleeping
* also acquired below.
*/
spin_unlock_bh(d->lock);
for (i = tc.offset; i < tc.offset + tc.count; i++) {
qdisc = netdev_get_tx_queue(dev, i)->qdisc;
spin_lock_bh(qdisc_lock(qdisc));
bstats.bytes += qdisc->bstats.bytes;
bstats.packets += qdisc->bstats.packets;
qstats.qlen += qdisc->qstats.qlen;
qstats.backlog += qdisc->qstats.backlog;
qstats.drops += qdisc->qstats.drops;
qstats.requeues += qdisc->qstats.requeues;
qstats.overlimits += qdisc->qstats.overlimits;
spin_unlock_bh(qdisc_lock(qdisc));
}
/* Reclaim root sleeping lock before completing stats */
spin_lock_bh(d->lock);
if (gnet_stats_copy_basic(d, &bstats) < 0 ||
gnet_stats_copy_queue(d, &qstats) < 0)
return -1;
} else {
struct netdev_queue *dev_queue = mqprio_queue_get(sch, cl);
sch = dev_queue->qdisc_sleeping;
sch->qstats.qlen = sch->q.qlen;
if (gnet_stats_copy_basic(d, &sch->bstats) < 0 ||
gnet_stats_copy_queue(d, &sch->qstats) < 0)
return -1;
}
return 0;
}
static void mqprio_walk(struct Qdisc *sch, struct qdisc_walker *arg)
{
struct net_device *dev = qdisc_dev(sch);
unsigned long ntx;
if (arg->stop)
return;
/* Walk hierarchy with a virtual class per tc */
arg->count = arg->skip;
for (ntx = arg->skip;
ntx < dev->num_tx_queues + netdev_get_num_tc(dev);
ntx++) {
if (arg->fn(sch, ntx + 1, arg) < 0) {
arg->stop = 1;
break;
}
arg->count++;
}
}
static const struct Qdisc_class_ops mqprio_class_ops = {
.graft = mqprio_graft,
.leaf = mqprio_leaf,
.get = mqprio_get,
.put = mqprio_put,
.walk = mqprio_walk,
.dump = mqprio_dump_class,
.dump_stats = mqprio_dump_class_stats,
};
static struct Qdisc_ops mqprio_qdisc_ops __read_mostly = {
.cl_ops = &mqprio_class_ops,
.id = "mqprio",
.priv_size = sizeof(struct mqprio_sched),
.init = mqprio_init,
.destroy = mqprio_destroy,
.attach = mqprio_attach,
.dump = mqprio_dump,
.owner = THIS_MODULE,
};
static int __init mqprio_module_init(void)
{
return register_qdisc(&mqprio_qdisc_ops);
}
static void __exit mqprio_module_exit(void)
{
unregister_qdisc(&mqprio_qdisc_ops);
}
module_init(mqprio_module_init);
module_exit(mqprio_module_exit);
MODULE_LICENSE("GPL");