static struct netdev_queue *mq_queue_get(struct Qdisc *sch, unsigned long cl)
{
struct net_device *dev = qdisc_dev(sch);
unsigned long ntx = cl - 1;
if (ntx >= dev->num_tx_queues)
return NULL;
return netdev_get_tx_queue(dev, ntx);
}
/*
* NOTE: Called under qdisc_lock(q) with locally disabled BH.
*
* __QDISC_STATE_RUNNING guarantees only one CPU can process
* this qdisc at a time. qdisc_lock(q) serializes queue accesses for
* this queue.
*
* netif_tx_lock serializes accesses to device driver.
*
* qdisc_lock(q) and netif_tx_lock are mutually exclusive,
* if one is grabbed, another must be free.
*
* Note, that this procedure can be called by a watchdog timer
*
* Returns to the caller:
* 0 - queue is empty or throttled.
* >0 - queue is not empty.
*
*/
static inline int qdisc_restart(struct Qdisc *q)
{
struct netdev_queue *txq;
int ret = NETDEV_TX_BUSY;
struct net_device *dev;
spinlock_t *root_lock;
struct sk_buff *skb;
/* Dequeue packet */
//从队列上取下一个要发送的数据包.
if (unlikely((skb = dequeue_skb(q)) == NULL))
return 0;
root_lock = qdisc_lock(q);
/* And release qdisc */
spin_unlock(root_lock);
dev = qdisc_dev(q);
txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
HARD_TX_LOCK(dev, txq, smp_processor_id());
//调用dev_hard_start_xmit吧数据包通过实际的链路发送出去...
if (!netif_tx_queue_stopped(txq) &&
!netif_tx_queue_frozen(txq))
ret = dev_hard_start_xmit(skb, dev, txq);
HARD_TX_UNLOCK(dev, txq);
spin_lock(root_lock);
switch (ret) {
case NETDEV_TX_OK:
/* Driver sent out skb successfully */
ret = qdisc_qlen(q);
break;
case NETDEV_TX_LOCKED:
/* Driver try lock failed */
ret = handle_dev_cpu_collision(skb, txq, q);
break;
default:
/* Driver returned NETDEV_TX_BUSY - requeue skb */
if (unlikely (ret != NETDEV_TX_BUSY && net_ratelimit()))
printk(KERN_WARNING "BUG %s code %d qlen %d\n",
dev->name, ret, q->q.qlen);
ret = dev_requeue_skb(skb, q);
break;
}
if (ret && (netif_tx_queue_stopped(txq) ||
netif_tx_queue_frozen(txq)))
ret = 0;
return ret;
}
static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc* qdisc)
{
struct sk_buff_head *list = prio2list(skb, qdisc);
if (skb_queue_len(list) < qdisc_dev(qdisc)->tx_queue_len) {
qdisc->q.qlen++;
return __qdisc_enqueue_tail(skb, qdisc, list);
}
return qdisc_drop(skb, qdisc);
}
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 = q->queues[i];
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, *old;
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);
old = q->queues[i];
q->queues[i] = child;
if (old != &noop_qdisc) {
qdisc_tree_decrease_qlen(old,
old->q.qlen);
qdisc_destroy(old);
}
sch_tree_unlock(sch);
}
}
}
return 0;
}
static int fifo_init(struct Qdisc *sch, struct nlattr *opt)
{
struct fifo_sched_data *q = qdisc_priv(sch);
if (opt == NULL) {
u32 limit = qdisc_dev(sch)->tx_queue_len ? : 1;
if (sch->ops == &bfifo_qdisc_ops)
limit *= psched_mtu(qdisc_dev(sch));
q->limit = limit;
} else {
static void mq_destroy(struct Qdisc *sch)
{
struct net_device *dev = qdisc_dev(sch);
struct mq_sched *priv = qdisc_priv(sch);
unsigned int ntx;
if (!priv->qdiscs)
return;
for (ntx = 0; ntx < dev->num_tx_queues && priv->qdiscs[ntx]; ntx++)
qdisc_destroy(priv->qdiscs[ntx]);
kfree(priv->qdiscs);
}
static struct netdev_queue *mq_select_queue(struct Qdisc *sch,
struct tcmsg *tcm)
{
unsigned int ntx = TC_H_MIN(tcm->tcm_parent);
struct netdev_queue *dev_queue = mq_queue_get(sch, ntx);
if (!dev_queue) {
struct net_device *dev = qdisc_dev(sch);
return netdev_get_tx_queue(dev, 0);
}
return dev_queue;
}
static int fifo_init(struct Qdisc *sch, struct nlattr *opt)
{
bool bypass;
bool is_bfifo = sch->ops == &bfifo_qdisc_ops;
if (opt == NULL) {
u32 limit = qdisc_dev(sch)->tx_queue_len ? : 1;
if (is_bfifo)
limit *= psched_mtu(qdisc_dev(sch));
sch->limit = limit;
} else {
static int gred_init(struct Qdisc *sch, struct nlattr *opt)
{
struct nlattr *tb[TCA_GRED_MAX + 1];
int err;
if (opt == NULL)
return -EINVAL;
err = nla_parse_nested(tb, TCA_GRED_MAX, opt, gred_policy);
if (err < 0)
return err;
if (tb[TCA_GRED_PARMS] || tb[TCA_GRED_STAB])
return -EINVAL;
if (tb[TCA_GRED_LIMIT])
sch->limit = nla_get_u32(tb[TCA_GRED_LIMIT]);
else
sch->limit = qdisc_dev(sch)->tx_queue_len
* psched_mtu(qdisc_dev(sch));
return gred_change_table_def(sch, tb[TCA_GRED_DPS]);
}
static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc *qdisc)
{
if (skb_queue_len(&qdisc->q) < qdisc_dev(qdisc)->tx_queue_len) {
int band = prio2band[skb->priority & TC_PRIO_MAX];
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
struct sk_buff_head *list = band2list(priv, band);
priv->bitmap |= (1 << band);
qdisc->q.qlen++;
return __qdisc_enqueue_tail(skb, qdisc, list);
}
return qdisc_drop(skb, qdisc);
}
static int sfq_init(struct Qdisc *sch, struct nlattr *opt)
{
struct sfq_sched_data *q = qdisc_priv(sch);
int i;
q->perturb_timer.function = sfq_perturbation;
q->perturb_timer.data = (unsigned long)sch;
init_timer_deferrable(&q->perturb_timer);
for (i = 0; i < SFQ_MAX_DEPTH + 1; i++) {
q->dep[i].next = i + SFQ_MAX_FLOWS;
q->dep[i].prev = i + SFQ_MAX_FLOWS;
}
q->limit = SFQ_MAX_DEPTH;
q->maxdepth = SFQ_MAX_DEPTH;
q->cur_depth = 0;
q->tail = NULL;
q->divisor = SFQ_DEFAULT_HASH_DIVISOR;
q->maxflows = SFQ_DEFAULT_FLOWS;
q->quantum = psched_mtu(qdisc_dev(sch));
q->scaled_quantum = SFQ_ALLOT_SIZE(q->quantum);
q->perturb_period = 0;
q->perturbation = prandom_u32();
if (opt) {
int err = sfq_change(sch, opt);
if (err)
return err;
}
q->ht = sfq_alloc(sizeof(q->ht[0]) * q->divisor);
q->slots = sfq_alloc(sizeof(q->slots[0]) * q->maxflows);
if (!q->ht || !q->slots) {
sfq_destroy(sch);
return -ENOMEM;
}
for (i = 0; i < q->divisor; i++)
q->ht[i] = SFQ_EMPTY_SLOT;
for (i = 0; i < q->maxflows; i++) {
slot_queue_init(&q->slots[i]);
sfq_link(q, i);
}
if (q->limit >= 1)
sch->flags |= TCQ_F_CAN_BYPASS;
else
sch->flags &= ~TCQ_F_CAN_BYPASS;
return 0;
}
static int sfq_init(struct Qdisc *sch, struct nlattr *opt)
{
struct sfq_sched_data *q = qdisc_priv(sch);
size_t sz;
int i;
q->perturb_timer.function = sfq_perturbation;
q->perturb_timer.data = (unsigned long)sch;
init_timer_deferrable(&q->perturb_timer);
for (i = 0; i < SFQ_DEPTH; i++) {
q->dep[i].next = i + SFQ_SLOTS;
q->dep[i].prev = i + SFQ_SLOTS;
}
q->limit = SFQ_DEPTH - 1;
q->cur_depth = 0;
q->tail = NULL;
q->divisor = SFQ_DEFAULT_HASH_DIVISOR;
if (opt == NULL) {
q->quantum = psched_mtu(qdisc_dev(sch));
q->scaled_quantum = SFQ_ALLOT_SIZE(q->quantum);
q->perturb_period = 0;
q->perturbation = net_random();
} else {
int err = sfq_change(sch, opt);
if (err)
return err;
}
sz = sizeof(q->ht[0]) * q->divisor;
q->ht = kmalloc(sz, GFP_KERNEL);
if (!q->ht && sz > PAGE_SIZE)
q->ht = vmalloc(sz);
if (!q->ht)
return -ENOMEM;
for (i = 0; i < q->divisor; i++)
q->ht[i] = SFQ_EMPTY_SLOT;
for (i = 0; i < SFQ_SLOTS; i++) {
slot_queue_init(&q->slots[i]);
sfq_link(q, i);
}
if (q->limit >= 1)
sch->flags |= TCQ_F_CAN_BYPASS;
else
sch->flags &= ~TCQ_F_CAN_BYPASS;
return 0;
}
static int
teql_enqueue(struct sk_buff *skb, struct Qdisc *sch)
{
struct net_device *dev = qdisc_dev(sch);
struct teql_sched_data *q = qdisc_priv(sch);
if (q->q.qlen < dev->tx_queue_len) {
__skb_queue_tail(&q->q, skb);
return NET_XMIT_SUCCESS;
}
kfree_skb(skb);
sch->qstats.drops++;
return NET_XMIT_DROP;
}
static int ingress_init(struct Qdisc *sch, struct nlattr *opt)
{
struct ingress_sched_data *q = qdisc_priv(sch);
struct net_device *dev = qdisc_dev(sch);
int err;
err = tcf_block_get(&q->block, &dev->ingress_cl_list);
if (err)
return err;
net_inc_ingress_queue();
sch->flags |= TCQ_F_CPUSTATS;
return 0;
}
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);
}
netdev_set_num_tc(dev, 0);
}
static int ingress_init(struct Qdisc *sch, struct nlattr *opt,
struct netlink_ext_ack *extack)
{
struct ingress_sched_data *q = qdisc_priv(sch);
struct net_device *dev = qdisc_dev(sch);
net_inc_ingress_queue();
mini_qdisc_pair_init(&q->miniqp, sch, &dev->miniq_ingress);
q->block_info.binder_type = TCF_BLOCK_BINDER_TYPE_CLSACT_INGRESS;
q->block_info.chain_head_change = clsact_chain_head_change;
q->block_info.chain_head_change_priv = &q->miniqp;
return tcf_block_get_ext(&q->block, sch, &q->block_info, extack);
}
static void mq_attach(struct Qdisc *sch)
{
struct net_device *dev = qdisc_dev(sch);
struct mq_sched *priv = qdisc_priv(sch);
struct Qdisc *qdisc;
unsigned int ntx;
for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
qdisc = priv->qdiscs[ntx];
qdisc = dev_graft_qdisc(qdisc->dev_queue, qdisc);
if (qdisc)
qdisc_destroy(qdisc);
}
kfree(priv->qdiscs);
priv->qdiscs = NULL;
}
static int teql_qdisc_init(struct Qdisc *sch, struct nlattr *opt)
{
struct net_device *dev = qdisc_dev(sch);
struct teql_master *m = (struct teql_master *)sch->ops;
struct teql_sched_data *q = qdisc_priv(sch);
if (dev->hard_header_len > m->dev->hard_header_len)
return -EINVAL;
if (m->dev == dev)
return -ELOOP;
q->m = m;
skb_queue_head_init(&q->q);
if (m->slaves) {
if (m->dev->flags & IFF_UP) {
if ((m->dev->flags & IFF_POINTOPOINT &&
!(dev->flags & IFF_POINTOPOINT)) ||
(m->dev->flags & IFF_BROADCAST &&
!(dev->flags & IFF_BROADCAST)) ||
(m->dev->flags & IFF_MULTICAST &&
!(dev->flags & IFF_MULTICAST)) ||
dev->mtu < m->dev->mtu)
return -EINVAL;
} else {
if (!(dev->flags&IFF_POINTOPOINT))
m->dev->flags &= ~IFF_POINTOPOINT;
if (!(dev->flags&IFF_BROADCAST))
m->dev->flags &= ~IFF_BROADCAST;
if (!(dev->flags&IFF_MULTICAST))
m->dev->flags &= ~IFF_MULTICAST;
if (dev->mtu < m->dev->mtu)
m->dev->mtu = dev->mtu;
}
q->next = NEXT_SLAVE(m->slaves);
NEXT_SLAVE(m->slaves) = sch;
} else {
q->next = sch;
m->slaves = sch;
m->dev->mtu = dev->mtu;
m->dev->flags = (m->dev->flags&~FMASK)|(dev->flags&FMASK);
}
return 0;
}
/*
* NOTE: Called under qdisc_lock(q) with locally disabled BH.
*
* __QDISC_STATE_RUNNING guarantees only one CPU can process
* this qdisc at a time. qdisc_lock(q) serializes queue accesses for
* this queue.
*
* netif_tx_lock serializes accesses to device driver.
*
* qdisc_lock(q) and netif_tx_lock are mutually exclusive,
* if one is grabbed, another must be free.
*
* Note, that this procedure can be called by a watchdog timer
*
* Returns to the caller:
* 0 - queue is empty or throttled.
* >0 - queue is not empty.
*
*/
static inline int qdisc_restart(struct Qdisc *q)
{
struct netdev_queue *txq;
struct net_device *dev;
spinlock_t *root_lock;
struct sk_buff *skb;
/* Dequeue packet */
skb = dequeue_skb(q);
if (unlikely(!skb))
return 0;
WARN_ON_ONCE(skb_dst_is_noref(skb));
root_lock = qdisc_lock(q);
dev = qdisc_dev(q);
txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
return sch_direct_xmit(skb, q, dev, txq, root_lock);
}
static int fq_codel_init(struct Qdisc *sch, struct nlattr *opt)
{
struct fq_codel_sched_data *q = qdisc_priv(sch);
int i;
sch->limit = 10*1024;
q->flows_cnt = 1024;
q->quantum = psched_mtu(qdisc_dev(sch));
q->perturbation = prandom_u32();
INIT_LIST_HEAD(&q->new_flows);
INIT_LIST_HEAD(&q->old_flows);
codel_params_init(&q->cparams);
codel_stats_init(&q->cstats);
q->cparams.ecn = true;
if (opt) {
int err = fq_codel_change(sch, opt);
if (err)
return err;
}
if (!q->flows) {
q->flows = fq_codel_zalloc(q->flows_cnt *
sizeof(struct fq_codel_flow));
if (!q->flows)
return -ENOMEM;
q->backlogs = fq_codel_zalloc(q->flows_cnt * sizeof(u32));
if (!q->backlogs) {
fq_codel_free(q->flows);
return -ENOMEM;
}
for (i = 0; i < q->flows_cnt; i++) {
struct fq_codel_flow *flow = q->flows + i;
INIT_LIST_HEAD(&flow->flowchain);
codel_vars_init(&flow->cvars);
}
}
if (sch->limit >= 1)
sch->flags |= TCQ_F_CAN_BYPASS;
else
sch->flags &= ~TCQ_F_CAN_BYPASS;
return 0;
}
/*
* NOTE: Called under qdisc_lock(q) with locally disabled BH.
*
* __QDISC___STATE_RUNNING guarantees only one CPU can process
* this qdisc at a time. qdisc_lock(q) serializes queue accesses for
* this queue.
*
* netif_tx_lock serializes accesses to device driver.
*
* qdisc_lock(q) and netif_tx_lock are mutually exclusive,
* if one is grabbed, another must be free.
*
* Note, that this procedure can be called by a watchdog timer
*
* Returns to the caller:
* 0 - queue is empty or throttled.
* >0 - queue is not empty.
*
*/
static inline int qdisc_restart(struct Qdisc *q, int *packets)
{
struct netdev_queue *txq;
struct net_device *dev;
spinlock_t *root_lock;
struct sk_buff *skb;
bool validate;
/* Dequeue packet */
skb = dequeue_skb(q, &validate, packets);
if (unlikely(!skb))
return 0;
root_lock = qdisc_lock(q);
dev = qdisc_dev(q);
txq = skb_get_tx_queue(dev, skb);
return sch_direct_xmit(skb, q, dev, txq, root_lock, validate);
}
static inline struct sk_buff *dequeue_skb(struct Qdisc *q)
{
struct sk_buff *skb = q->gso_skb;
if (unlikely(skb)) {
struct net_device *dev = qdisc_dev(q);
struct netdev_queue *txq;
/* check the reason of requeuing without tx lock first */
txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
if (!netif_tx_queue_stopped(txq) && !netif_tx_queue_frozen(txq))
q->gso_skb = NULL;
else
skb = NULL;
} else {
skb = q->dequeue(q);
}
return skb;
}
static void gred_offload(struct Qdisc *sch, enum tc_gred_command command)
{
struct gred_sched *table = qdisc_priv(sch);
struct net_device *dev = qdisc_dev(sch);
struct tc_gred_qopt_offload opt = {
.command = command,
.handle = sch->handle,
.parent = sch->parent,
};
if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
return;
if (command == TC_GRED_REPLACE) {
unsigned int i;
opt.set.grio_on = gred_rio_mode(table);
opt.set.wred_on = gred_wred_mode(table);
opt.set.dp_cnt = table->DPs;
opt.set.dp_def = table->def;
for (i = 0; i < table->DPs; i++) {
struct gred_sched_data *q = table->tab[i];
if (!q)
continue;
opt.set.tab[i].present = true;
opt.set.tab[i].limit = q->limit;
opt.set.tab[i].prio = q->prio;
opt.set.tab[i].min = q->parms.qth_min >> q->parms.Wlog;
opt.set.tab[i].max = q->parms.qth_max >> q->parms.Wlog;
opt.set.tab[i].is_ecn = gred_use_ecn(q);
opt.set.tab[i].is_harddrop = gred_use_harddrop(q);
opt.set.tab[i].probability = q->parms.max_P;
opt.set.tab[i].backlog = &q->backlog;
}
opt.set.qstats = &sch->qstats;
}
dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_GRED, &opt);
}
static struct sk_buff *
teql_dequeue(struct Qdisc *sch)
{
struct teql_sched_data *dat = qdisc_priv(sch);
struct netdev_queue *dat_queue;
struct sk_buff *skb;
skb = __skb_dequeue(&dat->q);
dat_queue = netdev_get_tx_queue(dat->m->dev, 0);
if (skb == NULL) {
struct net_device *m = qdisc_dev(dat_queue->qdisc);
if (m) {
dat->m->slaves = sch;
netif_wake_queue(m);
}
} else {
qdisc_bstats_update(sch, skb);
}
sch->q.qlen = dat->q.qlen + dat_queue->qdisc->q.qlen;
return skb;
}
static void mq_attach(struct Qdisc *sch)
{
struct net_device *dev = qdisc_dev(sch);
struct mq_sched *priv = qdisc_priv(sch);
struct Qdisc *qdisc, *old;
unsigned int ntx;
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);
#ifdef CONFIG_NET_SCHED
if (ntx < dev->real_num_tx_queues)
qdisc_list_add(qdisc);
#endif
}
kfree(priv->qdiscs);
priv->qdiscs = NULL;
}
static inline struct sk_buff *dequeue_skb(struct Qdisc *q)
{
struct sk_buff *skb = q->gso_skb;
if (unlikely(skb)) {
struct net_device *dev = qdisc_dev(q);
struct netdev_queue *txq;
txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
if (!netif_tx_queue_stopped(txq) &&
!netif_tx_queue_frozen(txq)) {
q->gso_skb = NULL;
q->q.qlen--;
} else
skb = NULL;
} else {
skb = q->dequeue(q);
}
return skb;
}
static int em_ipset_change(struct tcf_proto *tp, void *data, int data_len,
struct tcf_ematch *em)
{
struct xt_set_info *set = data;
ip_set_id_t index;
struct net *net = dev_net(qdisc_dev(tp->q));
if (data_len != sizeof(*set))
return -EINVAL;
index = ip_set_nfnl_get_byindex(net, set->index);
if (index == IPSET_INVALID_ID)
return -ENOENT;
em->datalen = sizeof(*set);
em->data = (unsigned long)kmemdup(data, em->datalen, GFP_KERNEL);
if (em->data)
return 0;
ip_set_nfnl_put(net, index);
return -ENOMEM;
}
static int mq_init(struct Qdisc *sch, struct nlattr *opt)
{
struct net_device *dev = qdisc_dev(sch);
struct mq_sched *priv = qdisc_priv(sch);
struct netdev_queue *dev_queue;
struct Qdisc *qdisc;
unsigned int ntx;
if (sch->parent != TC_H_ROOT)
return -EOPNOTSUPP;
if (!netif_is_multiqueue(dev))
return -EOPNOTSUPP;
/* pre-allocate qdiscs, attachment can't fail */
priv->qdiscs = kcalloc(dev->num_tx_queues, sizeof(priv->qdiscs[0]),
GFP_KERNEL);
if (priv->qdiscs == NULL)
return -ENOMEM;
for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
dev_queue = netdev_get_tx_queue(dev, ntx);
qdisc = qdisc_create_dflt(dev_queue, default_qdisc_ops,
TC_H_MAKE(TC_H_MAJ(sch->handle),
TC_H_MIN(ntx + 1)));
if (qdisc == NULL)
goto err;
priv->qdiscs[ntx] = qdisc;
qdisc->flags |= TCQ_F_ONETXQUEUE;
}
sch->flags |= TCQ_F_MQROOT;
return 0;
err:
mq_destroy(sch);
return -ENOMEM;
}
static struct mbuf *
generic_qdisc_dequeue(struct Qdisc *qdisc)
{
struct mbuf *m = qdisc_dequeue_head(qdisc);
if (!m) {
return NULL;
}
if (unlikely(m->priority == NM_MAGIC_PRIORITY_TXQE)) {
/* nm_os_generic_xmit_frame() asked us an event on this mbuf.
* We have to set the priority to the normal TX token, so that
* generic_ndo_start_xmit can pass it to the driver. */
m->priority = NM_MAGIC_PRIORITY_TX;
ND(5, "Event met, notify %p", m);
netmap_generic_irq(NA(qdisc_dev(qdisc)),
skb_get_queue_mapping(m), NULL);
}
ND(5, "Dequeuing mbuf, len %u", qdisc_qlen(qdisc));
return m;
}
static int sfq_init(struct Qdisc *sch, struct nlattr *opt)
{
struct sfq_sched_data *q = qdisc_priv(sch);
int i;
q->perturb_timer.function = sfq_perturbation;
q->perturb_timer.data = (unsigned long)sch;
init_timer_deferrable(&q->perturb_timer);
for (i = 0; i < SFQ_HASH_DIVISOR; i++)
q->ht[i] = SFQ_EMPTY_SLOT;
for (i = 0; i < SFQ_DEPTH; i++) {
q->dep[i].next = i + SFQ_SLOTS;
q->dep[i].prev = i + SFQ_SLOTS;
}
q->limit = SFQ_DEPTH - 1;
q->cur_depth = 0;
q->tail = NULL;
if (opt == NULL) {
q->quantum = psched_mtu(qdisc_dev(sch));
q->scaled_quantum = SFQ_ALLOT_SIZE(q->quantum);
q->perturb_period = 0;
q->perturbation = net_random();
} else {
int err = sfq_change(sch, opt);
if (err)
return err;
}
for (i = 0; i < SFQ_SLOTS; i++) {
slot_queue_init(&q->slots[i]);
sfq_link(q, i);
}
return 0;
}
