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author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/net/sched/sch_gred.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/net/sched/sch_gred.c')
-rw-r--r-- | kernel/net/sched/sch_gred.c | 630 |
1 files changed, 630 insertions, 0 deletions
diff --git a/kernel/net/sched/sch_gred.c b/kernel/net/sched/sch_gred.c new file mode 100644 index 000000000..634529e0c --- /dev/null +++ b/kernel/net/sched/sch_gred.c @@ -0,0 +1,630 @@ +/* + * net/sched/sch_gred.c Generic Random Early Detection queue. + * + * + * 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: J Hadi Salim (hadi@cyberus.ca) 1998-2002 + * + * 991129: - Bug fix with grio mode + * - a better sing. AvgQ mode with Grio(WRED) + * - A finer grained VQ dequeue based on sugestion + * from Ren Liu + * - More error checks + * + * For all the glorious comments look at include/net/red.h + */ + +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/skbuff.h> +#include <net/pkt_sched.h> +#include <net/red.h> + +#define GRED_DEF_PRIO (MAX_DPs / 2) +#define GRED_VQ_MASK (MAX_DPs - 1) + +struct gred_sched_data; +struct gred_sched; + +struct gred_sched_data { + u32 limit; /* HARD maximal queue length */ + u32 DP; /* the drop parameters */ + u32 bytesin; /* bytes seen on virtualQ so far*/ + u32 packetsin; /* packets seen on virtualQ so far*/ + u32 backlog; /* bytes on the virtualQ */ + u8 prio; /* the prio of this vq */ + + struct red_parms parms; + struct red_vars vars; + struct red_stats stats; +}; + +enum { + GRED_WRED_MODE = 1, + GRED_RIO_MODE, +}; + +struct gred_sched { + struct gred_sched_data *tab[MAX_DPs]; + unsigned long flags; + u32 red_flags; + u32 DPs; + u32 def; + struct red_vars wred_set; +}; + +static inline int gred_wred_mode(struct gred_sched *table) +{ + return test_bit(GRED_WRED_MODE, &table->flags); +} + +static inline void gred_enable_wred_mode(struct gred_sched *table) +{ + __set_bit(GRED_WRED_MODE, &table->flags); +} + +static inline void gred_disable_wred_mode(struct gred_sched *table) +{ + __clear_bit(GRED_WRED_MODE, &table->flags); +} + +static inline int gred_rio_mode(struct gred_sched *table) +{ + return test_bit(GRED_RIO_MODE, &table->flags); +} + +static inline void gred_enable_rio_mode(struct gred_sched *table) +{ + __set_bit(GRED_RIO_MODE, &table->flags); +} + +static inline void gred_disable_rio_mode(struct gred_sched *table) +{ + __clear_bit(GRED_RIO_MODE, &table->flags); +} + +static inline int gred_wred_mode_check(struct Qdisc *sch) +{ + struct gred_sched *table = qdisc_priv(sch); + int i; + + /* Really ugly O(n^2) but shouldn't be necessary too frequent. */ + for (i = 0; i < table->DPs; i++) { + struct gred_sched_data *q = table->tab[i]; + int n; + + if (q == NULL) + continue; + + for (n = i + 1; n < table->DPs; n++) + if (table->tab[n] && table->tab[n]->prio == q->prio) + return 1; + } + + return 0; +} + +static inline unsigned int gred_backlog(struct gred_sched *table, + struct gred_sched_data *q, + struct Qdisc *sch) +{ + if (gred_wred_mode(table)) + return sch->qstats.backlog; + else + return q->backlog; +} + +static inline u16 tc_index_to_dp(struct sk_buff *skb) +{ + return skb->tc_index & GRED_VQ_MASK; +} + +static inline void gred_load_wred_set(const struct gred_sched *table, + struct gred_sched_data *q) +{ + q->vars.qavg = table->wred_set.qavg; + q->vars.qidlestart = table->wred_set.qidlestart; +} + +static inline void gred_store_wred_set(struct gred_sched *table, + struct gred_sched_data *q) +{ + table->wred_set.qavg = q->vars.qavg; + table->wred_set.qidlestart = q->vars.qidlestart; +} + +static inline int gred_use_ecn(struct gred_sched *t) +{ + return t->red_flags & TC_RED_ECN; +} + +static inline int gred_use_harddrop(struct gred_sched *t) +{ + return t->red_flags & TC_RED_HARDDROP; +} + +static int gred_enqueue(struct sk_buff *skb, struct Qdisc *sch) +{ + struct gred_sched_data *q = NULL; + struct gred_sched *t = qdisc_priv(sch); + unsigned long qavg = 0; + u16 dp = tc_index_to_dp(skb); + + if (dp >= t->DPs || (q = t->tab[dp]) == NULL) { + dp = t->def; + + q = t->tab[dp]; + if (!q) { + /* Pass through packets not assigned to a DP + * if no default DP has been configured. This + * allows for DP flows to be left untouched. + */ + if (skb_queue_len(&sch->q) < qdisc_dev(sch)->tx_queue_len) + return qdisc_enqueue_tail(skb, sch); + else + goto drop; + } + + /* fix tc_index? --could be controversial but needed for + requeueing */ + skb->tc_index = (skb->tc_index & ~GRED_VQ_MASK) | dp; + } + + /* sum up all the qaves of prios < ours to get the new qave */ + if (!gred_wred_mode(t) && gred_rio_mode(t)) { + int i; + + for (i = 0; i < t->DPs; i++) { + if (t->tab[i] && t->tab[i]->prio < q->prio && + !red_is_idling(&t->tab[i]->vars)) + qavg += t->tab[i]->vars.qavg; + } + + } + + q->packetsin++; + q->bytesin += qdisc_pkt_len(skb); + + if (gred_wred_mode(t)) + gred_load_wred_set(t, q); + + q->vars.qavg = red_calc_qavg(&q->parms, + &q->vars, + gred_backlog(t, q, sch)); + + if (red_is_idling(&q->vars)) + red_end_of_idle_period(&q->vars); + + if (gred_wred_mode(t)) + gred_store_wred_set(t, q); + + switch (red_action(&q->parms, &q->vars, q->vars.qavg + qavg)) { + case RED_DONT_MARK: + break; + + case RED_PROB_MARK: + qdisc_qstats_overlimit(sch); + if (!gred_use_ecn(t) || !INET_ECN_set_ce(skb)) { + q->stats.prob_drop++; + goto congestion_drop; + } + + q->stats.prob_mark++; + break; + + case RED_HARD_MARK: + qdisc_qstats_overlimit(sch); + if (gred_use_harddrop(t) || !gred_use_ecn(t) || + !INET_ECN_set_ce(skb)) { + q->stats.forced_drop++; + goto congestion_drop; + } + q->stats.forced_mark++; + break; + } + + if (gred_backlog(t, q, sch) + qdisc_pkt_len(skb) <= q->limit) { + q->backlog += qdisc_pkt_len(skb); + return qdisc_enqueue_tail(skb, sch); + } + + q->stats.pdrop++; +drop: + return qdisc_drop(skb, sch); + +congestion_drop: + qdisc_drop(skb, sch); + return NET_XMIT_CN; +} + +static struct sk_buff *gred_dequeue(struct Qdisc *sch) +{ + struct sk_buff *skb; + struct gred_sched *t = qdisc_priv(sch); + + skb = qdisc_dequeue_head(sch); + + if (skb) { + struct gred_sched_data *q; + u16 dp = tc_index_to_dp(skb); + + if (dp >= t->DPs || (q = t->tab[dp]) == NULL) { + net_warn_ratelimited("GRED: Unable to relocate VQ 0x%x after dequeue, screwing up backlog\n", + tc_index_to_dp(skb)); + } else { + q->backlog -= qdisc_pkt_len(skb); + + if (gred_wred_mode(t)) { + if (!sch->qstats.backlog) + red_start_of_idle_period(&t->wred_set); + } else { + if (!q->backlog) + red_start_of_idle_period(&q->vars); + } + } + + return skb; + } + + return NULL; +} + +static unsigned int gred_drop(struct Qdisc *sch) +{ + struct sk_buff *skb; + struct gred_sched *t = qdisc_priv(sch); + + skb = qdisc_dequeue_tail(sch); + if (skb) { + unsigned int len = qdisc_pkt_len(skb); + struct gred_sched_data *q; + u16 dp = tc_index_to_dp(skb); + + if (dp >= t->DPs || (q = t->tab[dp]) == NULL) { + net_warn_ratelimited("GRED: Unable to relocate VQ 0x%x while dropping, screwing up backlog\n", + tc_index_to_dp(skb)); + } else { + q->backlog -= len; + q->stats.other++; + + if (gred_wred_mode(t)) { + if (!sch->qstats.backlog) + red_start_of_idle_period(&t->wred_set); + } else { + if (!q->backlog) + red_start_of_idle_period(&q->vars); + } + } + + qdisc_drop(skb, sch); + return len; + } + + return 0; +} + +static void gred_reset(struct Qdisc *sch) +{ + int i; + struct gred_sched *t = qdisc_priv(sch); + + qdisc_reset_queue(sch); + + for (i = 0; i < t->DPs; i++) { + struct gred_sched_data *q = t->tab[i]; + + if (!q) + continue; + + red_restart(&q->vars); + q->backlog = 0; + } +} + +static inline void gred_destroy_vq(struct gred_sched_data *q) +{ + kfree(q); +} + +static inline int gred_change_table_def(struct Qdisc *sch, struct nlattr *dps) +{ + struct gred_sched *table = qdisc_priv(sch); + struct tc_gred_sopt *sopt; + int i; + + if (dps == NULL) + return -EINVAL; + + sopt = nla_data(dps); + + if (sopt->DPs > MAX_DPs || sopt->DPs == 0 || sopt->def_DP >= sopt->DPs) + return -EINVAL; + + sch_tree_lock(sch); + table->DPs = sopt->DPs; + table->def = sopt->def_DP; + table->red_flags = sopt->flags; + + /* + * Every entry point to GRED is synchronized with the above code + * and the DP is checked against DPs, i.e. shadowed VQs can no + * longer be found so we can unlock right here. + */ + sch_tree_unlock(sch); + + if (sopt->grio) { + gred_enable_rio_mode(table); + gred_disable_wred_mode(table); + if (gred_wred_mode_check(sch)) + gred_enable_wred_mode(table); + } else { + gred_disable_rio_mode(table); + gred_disable_wred_mode(table); + } + + for (i = table->DPs; i < MAX_DPs; i++) { + if (table->tab[i]) { + pr_warn("GRED: Warning: Destroying shadowed VQ 0x%x\n", + i); + gred_destroy_vq(table->tab[i]); + table->tab[i] = NULL; + } + } + + return 0; +} + +static inline int gred_change_vq(struct Qdisc *sch, int dp, + struct tc_gred_qopt *ctl, int prio, + u8 *stab, u32 max_P, + struct gred_sched_data **prealloc) +{ + struct gred_sched *table = qdisc_priv(sch); + struct gred_sched_data *q = table->tab[dp]; + + if (!q) { + table->tab[dp] = q = *prealloc; + *prealloc = NULL; + if (!q) + return -ENOMEM; + } + + q->DP = dp; + q->prio = prio; + q->limit = ctl->limit; + + if (q->backlog == 0) + red_end_of_idle_period(&q->vars); + + red_set_parms(&q->parms, + ctl->qth_min, ctl->qth_max, ctl->Wlog, ctl->Plog, + ctl->Scell_log, stab, max_P); + red_set_vars(&q->vars); + return 0; +} + +static const struct nla_policy gred_policy[TCA_GRED_MAX + 1] = { + [TCA_GRED_PARMS] = { .len = sizeof(struct tc_gred_qopt) }, + [TCA_GRED_STAB] = { .len = 256 }, + [TCA_GRED_DPS] = { .len = sizeof(struct tc_gred_sopt) }, + [TCA_GRED_MAX_P] = { .type = NLA_U32 }, +}; + +static int gred_change(struct Qdisc *sch, struct nlattr *opt) +{ + struct gred_sched *table = qdisc_priv(sch); + struct tc_gred_qopt *ctl; + struct nlattr *tb[TCA_GRED_MAX + 1]; + int err, prio = GRED_DEF_PRIO; + u8 *stab; + u32 max_P; + struct gred_sched_data *prealloc; + + 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] == NULL && tb[TCA_GRED_STAB] == NULL) + return gred_change_table_def(sch, opt); + + if (tb[TCA_GRED_PARMS] == NULL || + tb[TCA_GRED_STAB] == NULL) + return -EINVAL; + + max_P = tb[TCA_GRED_MAX_P] ? nla_get_u32(tb[TCA_GRED_MAX_P]) : 0; + + err = -EINVAL; + ctl = nla_data(tb[TCA_GRED_PARMS]); + stab = nla_data(tb[TCA_GRED_STAB]); + + if (ctl->DP >= table->DPs) + goto errout; + + if (gred_rio_mode(table)) { + if (ctl->prio == 0) { + int def_prio = GRED_DEF_PRIO; + + if (table->tab[table->def]) + def_prio = table->tab[table->def]->prio; + + printk(KERN_DEBUG "GRED: DP %u does not have a prio " + "setting default to %d\n", ctl->DP, def_prio); + + prio = def_prio; + } else + prio = ctl->prio; + } + + prealloc = kzalloc(sizeof(*prealloc), GFP_KERNEL); + sch_tree_lock(sch); + + err = gred_change_vq(sch, ctl->DP, ctl, prio, stab, max_P, &prealloc); + if (err < 0) + goto errout_locked; + + if (gred_rio_mode(table)) { + gred_disable_wred_mode(table); + if (gred_wred_mode_check(sch)) + gred_enable_wred_mode(table); + } + + err = 0; + +errout_locked: + sch_tree_unlock(sch); + kfree(prealloc); +errout: + return err; +} + +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; + + return gred_change_table_def(sch, tb[TCA_GRED_DPS]); +} + +static int gred_dump(struct Qdisc *sch, struct sk_buff *skb) +{ + struct gred_sched *table = qdisc_priv(sch); + struct nlattr *parms, *opts = NULL; + int i; + u32 max_p[MAX_DPs]; + struct tc_gred_sopt sopt = { + .DPs = table->DPs, + .def_DP = table->def, + .grio = gred_rio_mode(table), + .flags = table->red_flags, + }; + + opts = nla_nest_start(skb, TCA_OPTIONS); + if (opts == NULL) + goto nla_put_failure; + if (nla_put(skb, TCA_GRED_DPS, sizeof(sopt), &sopt)) + goto nla_put_failure; + + for (i = 0; i < MAX_DPs; i++) { + struct gred_sched_data *q = table->tab[i]; + + max_p[i] = q ? q->parms.max_P : 0; + } + if (nla_put(skb, TCA_GRED_MAX_P, sizeof(max_p), max_p)) + goto nla_put_failure; + + parms = nla_nest_start(skb, TCA_GRED_PARMS); + if (parms == NULL) + goto nla_put_failure; + + for (i = 0; i < MAX_DPs; i++) { + struct gred_sched_data *q = table->tab[i]; + struct tc_gred_qopt opt; + unsigned long qavg; + + memset(&opt, 0, sizeof(opt)); + + if (!q) { + /* hack -- fix at some point with proper message + This is how we indicate to tc that there is no VQ + at this DP */ + + opt.DP = MAX_DPs + i; + goto append_opt; + } + + opt.limit = q->limit; + opt.DP = q->DP; + opt.backlog = gred_backlog(table, q, sch); + opt.prio = q->prio; + opt.qth_min = q->parms.qth_min >> q->parms.Wlog; + opt.qth_max = q->parms.qth_max >> q->parms.Wlog; + opt.Wlog = q->parms.Wlog; + opt.Plog = q->parms.Plog; + opt.Scell_log = q->parms.Scell_log; + opt.other = q->stats.other; + opt.early = q->stats.prob_drop; + opt.forced = q->stats.forced_drop; + opt.pdrop = q->stats.pdrop; + opt.packets = q->packetsin; + opt.bytesin = q->bytesin; + + if (gred_wred_mode(table)) + gred_load_wred_set(table, q); + + qavg = red_calc_qavg(&q->parms, &q->vars, + q->vars.qavg >> q->parms.Wlog); + opt.qave = qavg >> q->parms.Wlog; + +append_opt: + if (nla_append(skb, sizeof(opt), &opt) < 0) + goto nla_put_failure; + } + + nla_nest_end(skb, parms); + + return nla_nest_end(skb, opts); + +nla_put_failure: + nla_nest_cancel(skb, opts); + return -EMSGSIZE; +} + +static void gred_destroy(struct Qdisc *sch) +{ + struct gred_sched *table = qdisc_priv(sch); + int i; + + for (i = 0; i < table->DPs; i++) { + if (table->tab[i]) + gred_destroy_vq(table->tab[i]); + } +} + +static struct Qdisc_ops gred_qdisc_ops __read_mostly = { + .id = "gred", + .priv_size = sizeof(struct gred_sched), + .enqueue = gred_enqueue, + .dequeue = gred_dequeue, + .peek = qdisc_peek_head, + .drop = gred_drop, + .init = gred_init, + .reset = gred_reset, + .destroy = gred_destroy, + .change = gred_change, + .dump = gred_dump, + .owner = THIS_MODULE, +}; + +static int __init gred_module_init(void) +{ + return register_qdisc(&gred_qdisc_ops); +} + +static void __exit gred_module_exit(void) +{ + unregister_qdisc(&gred_qdisc_ops); +} + +module_init(gred_module_init) +module_exit(gred_module_exit) + +MODULE_LICENSE("GPL"); |