static void pfifo_fast_reset(struct Qdisc *qdisc)
{
int i, band;
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
for (band = 0; band < PFIFO_FAST_BANDS; band++) {
struct skb_array *q = band2list(priv, band);
struct sk_buff *skb;
/* NULL ring is possible if destroy path is due to a failed
* skb_array_init() in pfifo_fast_init() case.
*/
if (!q->ring.queue)
continue;
while ((skb = skb_array_consume_bh(q)) != NULL)
kfree_skb(skb);
}
for_each_possible_cpu(i) {
struct gnet_stats_queue *q = per_cpu_ptr(qdisc->cpu_qstats, i);
q->backlog = 0;
q->qlen = 0;
}
}
static int pfifo_fast_init(struct Qdisc *qdisc, struct nlattr *opt)
{
int prio;
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
for (prio = 0; prio < PFIFO_FAST_BANDS; prio++)
__skb_queue_head_init(band2list(priv, prio));
/* Can by-pass the queue discipline */
qdisc->flags |= TCQ_F_CAN_BYPASS;
return 0;
}
static void pfifo_fast_reset(struct Qdisc *qdisc)
{
int prio;
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
for (prio = 0; prio < PFIFO_FAST_BANDS; prio++)
__qdisc_reset_queue(qdisc, band2list(priv, prio));
priv->bitmap = 0;
qdisc->qstats.backlog = 0;
qdisc->q.qlen = 0;
}
static struct sk_buff *pfifo_fast_peek(struct Qdisc *qdisc)
{
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
int band = bitmap2band[priv->bitmap];
if (band >= 0) {
struct sk_buff_head *list = band2list(priv, band);
return skb_peek(list);
}
return NULL;
}
static struct sk_buff *pfifo_fast_peek(struct Qdisc *qdisc)
{
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
struct sk_buff *skb = NULL;
int band;
for (band = 0; band < PFIFO_FAST_BANDS && !skb; band++) {
struct skb_array *q = band2list(priv, band);
skb = __skb_array_peek(q);
}
return skb;
}
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 pfifo_fast_change_tx_queue_len(struct Qdisc *sch,
unsigned int new_len)
{
struct pfifo_fast_priv *priv = qdisc_priv(sch);
struct skb_array *bands[PFIFO_FAST_BANDS];
int prio;
for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) {
struct skb_array *q = band2list(priv, prio);
bands[prio] = q;
}
return skb_array_resize_multiple(bands, PFIFO_FAST_BANDS, new_len,
GFP_KERNEL);
}
static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc *qdisc,
struct sk_buff **to_free)
{
int band = prio2band[skb->priority & TC_PRIO_MAX];
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
struct skb_array *q = band2list(priv, band);
int err;
err = skb_array_produce(q, skb);
if (unlikely(err))
return qdisc_drop_cpu(skb, qdisc, to_free);
qdisc_qstats_cpu_qlen_inc(qdisc);
qdisc_qstats_cpu_backlog_inc(qdisc, skb);
return NET_XMIT_SUCCESS;
}
static struct sk_buff *pfifo_fast_dequeue(struct Qdisc *qdisc)
{
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
int band = bitmap2band[priv->bitmap];
if (likely(band >= 0)) {
struct sk_buff_head *list = band2list(priv, band);
struct sk_buff *skb = __qdisc_dequeue_head(qdisc, list);
qdisc->q.qlen--;
if (skb_queue_empty(list))
priv->bitmap &= ~(1 << band);
return skb;
}
return NULL;
}
static void pfifo_fast_destroy(struct Qdisc *sch)
{
struct pfifo_fast_priv *priv = qdisc_priv(sch);
int prio;
for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) {
struct skb_array *q = band2list(priv, prio);
/* NULL ring is possible if destroy path is due to a failed
* skb_array_init() in pfifo_fast_init() case.
*/
if (!q->ring.queue)
continue;
/* Destroy ring but no need to kfree_skb because a call to
* pfifo_fast_reset() has already done that work.
*/
ptr_ring_cleanup(&q->ring, NULL);
}
}
static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc *qdisc,
struct sk_buff **to_free)
{
int band = prio2band[skb->priority & TC_PRIO_MAX];
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
struct skb_array *q = band2list(priv, band);
unsigned int pkt_len = qdisc_pkt_len(skb);
int err;
err = skb_array_produce(q, skb);
if (unlikely(err))
return qdisc_drop_cpu(skb, qdisc, to_free);
qdisc_qstats_cpu_qlen_inc(qdisc);
/* Note: skb can not be used after skb_array_produce(),
* so we better not use qdisc_qstats_cpu_backlog_inc()
*/
this_cpu_add(qdisc->cpu_qstats->backlog, pkt_len);
return NET_XMIT_SUCCESS;
}
static struct sk_buff *pfifo_fast_dequeue(struct Qdisc *qdisc)
{
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
struct sk_buff *skb = NULL;
int band;
for (band = 0; band < PFIFO_FAST_BANDS && !skb; band++) {
struct skb_array *q = band2list(priv, band);
if (__skb_array_empty(q))
continue;
skb = skb_array_consume_bh(q);
}
if (likely(skb)) {
qdisc_qstats_cpu_backlog_dec(qdisc, skb);
qdisc_bstats_cpu_update(qdisc, skb);
qdisc_qstats_cpu_qlen_dec(qdisc);
}
return skb;
}
static int pfifo_fast_init(struct Qdisc *qdisc, struct nlattr *opt,
struct netlink_ext_ack *extack)
{
unsigned int qlen = qdisc_dev(qdisc)->tx_queue_len;
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
int prio;
/* guard against zero length rings */
if (!qlen)
return -EINVAL;
for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) {
struct skb_array *q = band2list(priv, prio);
int err;
err = skb_array_init(q, qlen, GFP_KERNEL);
if (err)
return -ENOMEM;
}
/* Can by-pass the queue discipline */
qdisc->flags |= TCQ_F_CAN_BYPASS;
return 0;
}
