diff options
Diffstat (limited to 'kernel/net/sched/sch_prio.c')
| -rw-r--r-- | kernel/net/sched/sch_prio.c | 408 |
1 files changed, 408 insertions, 0 deletions
diff --git a/kernel/net/sched/sch_prio.c b/kernel/net/sched/sch_prio.c new file mode 100644 index 000000000..8e5cd34aa --- /dev/null +++ b/kernel/net/sched/sch_prio.c @@ -0,0 +1,408 @@ +/* + * 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/slab.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 __rcu *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; + struct tcf_proto *fl; + int err; + + *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS; + if (TC_H_MAJ(skb->priority) != sch->handle) { + fl = rcu_dereference_bh(q->filter_list); + err = tc_classify(skb, fl, &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 (!fl || 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) + qdisc_qstats_drop(sch); + kfree_skb(skb); + return ret; + } +#endif + + ret = qdisc_enqueue(skb, qdisc); + if (ret == NET_XMIT_SUCCESS) { + sch->q.qlen++; + return NET_XMIT_SUCCESS; + } + if (net_xmit_drop_count(ret)) + qdisc_qstats_drop(sch); + return ret; +} + +static struct sk_buff *prio_peek(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->ops->peek(qdisc); + if (skb) + return skb; + } + return NULL; +} + +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_peeked(qdisc); + if (skb) { + qdisc_bstats_update(sch, 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 = 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(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 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); + + 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 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 (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; + + 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) +{ +} + +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); + + tcm->tcm_handle |= TC_H_MIN(cl); + 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, NULL, &cl_q->bstats) < 0 || + gnet_stats_copy_queue(d, NULL, &cl_q->qstats, cl_q->q.qlen) < 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 __rcu **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, + .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, + .peek = prio_peek, + .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"); |