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1/*
2 * net/sched/sch_red.c Random Early Detection queue.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 *
11 * Changes:
12 * J Hadi Salim 980914: computation fixes
13 * Alexey Makarenko <makar@phoenix.kharkov.ua> 990814: qave on idle link was calculated incorrectly.
14 * J Hadi Salim 980816: ECN support
15 */
16
17#include <linux/module.h>
18#include <linux/types.h>
19#include <linux/kernel.h>
20#include <linux/skbuff.h>
21#include <net/pkt_sched.h>
22#include <net/pkt_cls.h>
23#include <net/inet_ecn.h>
24#include <net/red.h>
25
26
27/* Parameters, settable by user:
28 -----------------------------
29
30 limit - bytes (must be > qth_max + burst)
31
32 Hard limit on queue length, should be chosen >qth_max
33 to allow packet bursts. This parameter does not
34 affect the algorithms behaviour and can be chosen
35 arbitrarily high (well, less than ram size)
36 Really, this limit will never be reached
37 if RED works correctly.
38 */
39
40struct red_sched_data {
41 u32 limit; /* HARD maximal queue length */
42 unsigned char flags;
43 struct timer_list adapt_timer;
44 struct Qdisc *sch;
45 struct red_parms parms;
46 struct red_vars vars;
47 struct red_stats stats;
48 struct Qdisc *qdisc;
49};
50
51static inline int red_use_ecn(struct red_sched_data *q)
52{
53 return q->flags & TC_RED_ECN;
54}
55
56static inline int red_use_harddrop(struct red_sched_data *q)
57{
58 return q->flags & TC_RED_HARDDROP;
59}
60
61static int red_enqueue(struct sk_buff *skb, struct Qdisc *sch,
62 struct sk_buff **to_free)
63{
64 struct red_sched_data *q = qdisc_priv(sch);
65 struct Qdisc *child = q->qdisc;
66 int ret;
67
68 q->vars.qavg = red_calc_qavg(&q->parms,
69 &q->vars,
70 child->qstats.backlog);
71
72 if (red_is_idling(&q->vars))
73 red_end_of_idle_period(&q->vars);
74
75 switch (red_action(&q->parms, &q->vars, q->vars.qavg)) {
76 case RED_DONT_MARK:
77 break;
78
79 case RED_PROB_MARK:
80 qdisc_qstats_overlimit(sch);
81 if (!red_use_ecn(q) || !INET_ECN_set_ce(skb)) {
82 q->stats.prob_drop++;
83 goto congestion_drop;
84 }
85
86 q->stats.prob_mark++;
87 break;
88
89 case RED_HARD_MARK:
90 qdisc_qstats_overlimit(sch);
91 if (red_use_harddrop(q) || !red_use_ecn(q) ||
92 !INET_ECN_set_ce(skb)) {
93 q->stats.forced_drop++;
94 goto congestion_drop;
95 }
96
97 q->stats.forced_mark++;
98 break;
99 }
100
101 ret = qdisc_enqueue(skb, child, to_free);
102 if (likely(ret == NET_XMIT_SUCCESS)) {
103 qdisc_qstats_backlog_inc(sch, skb);
104 sch->q.qlen++;
105 } else if (net_xmit_drop_count(ret)) {
106 q->stats.pdrop++;
107 qdisc_qstats_drop(sch);
108 }
109 return ret;
110
111congestion_drop:
112 qdisc_drop(skb, sch, to_free);
113 return NET_XMIT_CN;
114}
115
116static struct sk_buff *red_dequeue(struct Qdisc *sch)
117{
118 struct sk_buff *skb;
119 struct red_sched_data *q = qdisc_priv(sch);
120 struct Qdisc *child = q->qdisc;
121
122 skb = child->dequeue(child);
123 if (skb) {
124 qdisc_bstats_update(sch, skb);
125 qdisc_qstats_backlog_dec(sch, skb);
126 sch->q.qlen--;
127 } else {
128 if (!red_is_idling(&q->vars))
129 red_start_of_idle_period(&q->vars);
130 }
131 return skb;
132}
133
134static struct sk_buff *red_peek(struct Qdisc *sch)
135{
136 struct red_sched_data *q = qdisc_priv(sch);
137 struct Qdisc *child = q->qdisc;
138
139 return child->ops->peek(child);
140}
141
142static void red_reset(struct Qdisc *sch)
143{
144 struct red_sched_data *q = qdisc_priv(sch);
145
146 qdisc_reset(q->qdisc);
147 sch->qstats.backlog = 0;
148 sch->q.qlen = 0;
149 red_restart(&q->vars);
150}
151
152static int red_offload(struct Qdisc *sch, bool enable)
153{
154 struct red_sched_data *q = qdisc_priv(sch);
155 struct net_device *dev = qdisc_dev(sch);
156 struct tc_red_qopt_offload opt = {
157 .handle = sch->handle,
158 .parent = sch->parent,
159 };
160
161 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
162 return -EOPNOTSUPP;
163
164 if (enable) {
165 opt.command = TC_RED_REPLACE;
166 opt.set.min = q->parms.qth_min >> q->parms.Wlog;
167 opt.set.max = q->parms.qth_max >> q->parms.Wlog;
168 opt.set.probability = q->parms.max_P;
169 opt.set.is_ecn = red_use_ecn(q);
170 opt.set.qstats = &sch->qstats;
171 } else {
172 opt.command = TC_RED_DESTROY;
173 }
174
175 return dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_RED, &opt);
176}
177
178static void red_destroy(struct Qdisc *sch)
179{
180 struct red_sched_data *q = qdisc_priv(sch);
181
182 del_timer_sync(&q->adapt_timer);
183 red_offload(sch, false);
184 qdisc_destroy(q->qdisc);
185}
186
187static const struct nla_policy red_policy[TCA_RED_MAX + 1] = {
188 [TCA_RED_PARMS] = { .len = sizeof(struct tc_red_qopt) },
189 [TCA_RED_STAB] = { .len = RED_STAB_SIZE },
190 [TCA_RED_MAX_P] = { .type = NLA_U32 },
191};
192
193static int red_change(struct Qdisc *sch, struct nlattr *opt,
194 struct netlink_ext_ack *extack)
195{
196 struct red_sched_data *q = qdisc_priv(sch);
197 struct nlattr *tb[TCA_RED_MAX + 1];
198 struct tc_red_qopt *ctl;
199 struct Qdisc *child = NULL;
200 int err;
201 u32 max_P;
202
203 if (opt == NULL)
204 return -EINVAL;
205
206 err = nla_parse_nested(tb, TCA_RED_MAX, opt, red_policy, NULL);
207 if (err < 0)
208 return err;
209
210 if (tb[TCA_RED_PARMS] == NULL ||
211 tb[TCA_RED_STAB] == NULL)
212 return -EINVAL;
213
214 max_P = tb[TCA_RED_MAX_P] ? nla_get_u32(tb[TCA_RED_MAX_P]) : 0;
215
216 ctl = nla_data(tb[TCA_RED_PARMS]);
217 if (!red_check_params(ctl->qth_min, ctl->qth_max, ctl->Wlog))
218 return -EINVAL;
219
220 if (ctl->limit > 0) {
221 child = fifo_create_dflt(sch, &bfifo_qdisc_ops, ctl->limit,
222 extack);
223 if (IS_ERR(child))
224 return PTR_ERR(child);
225
226 /* child is fifo, no need to check for noop_qdisc */
227 qdisc_hash_add(child, true);
228 }
229
230 sch_tree_lock(sch);
231 q->flags = ctl->flags;
232 q->limit = ctl->limit;
233 if (child) {
234 qdisc_tree_reduce_backlog(q->qdisc, q->qdisc->q.qlen,
235 q->qdisc->qstats.backlog);
236 qdisc_destroy(q->qdisc);
237 q->qdisc = child;
238 }
239
240 red_set_parms(&q->parms,
241 ctl->qth_min, ctl->qth_max, ctl->Wlog,
242 ctl->Plog, ctl->Scell_log,
243 nla_data(tb[TCA_RED_STAB]),
244 max_P);
245 red_set_vars(&q->vars);
246
247 del_timer(&q->adapt_timer);
248 if (ctl->flags & TC_RED_ADAPTATIVE)
249 mod_timer(&q->adapt_timer, jiffies + HZ/2);
250
251 if (!q->qdisc->q.qlen)
252 red_start_of_idle_period(&q->vars);
253
254 sch_tree_unlock(sch);
255 red_offload(sch, true);
256 return 0;
257}
258
259static inline void red_adaptative_timer(struct timer_list *t)
260{
261 struct red_sched_data *q = from_timer(q, t, adapt_timer);
262 struct Qdisc *sch = q->sch;
263 spinlock_t *root_lock = qdisc_lock(qdisc_root_sleeping(sch));
264
265 spin_lock(root_lock);
266 red_adaptative_algo(&q->parms, &q->vars);
267 mod_timer(&q->adapt_timer, jiffies + HZ/2);
268 spin_unlock(root_lock);
269}
270
271static int red_init(struct Qdisc *sch, struct nlattr *opt,
272 struct netlink_ext_ack *extack)
273{
274 struct red_sched_data *q = qdisc_priv(sch);
275
276 q->qdisc = &noop_qdisc;
277 q->sch = sch;
278 timer_setup(&q->adapt_timer, red_adaptative_timer, 0);
279 return red_change(sch, opt, extack);
280}
281
282static int red_dump_offload_stats(struct Qdisc *sch, struct tc_red_qopt *opt)
283{
284 struct net_device *dev = qdisc_dev(sch);
285 struct tc_red_qopt_offload hw_stats = {
286 .command = TC_RED_STATS,
287 .handle = sch->handle,
288 .parent = sch->parent,
289 {
290 .stats.bstats = &sch->bstats,
291 .stats.qstats = &sch->qstats,
292 },
293 };
294 int err;
295
296 sch->flags &= ~TCQ_F_OFFLOADED;
297
298 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
299 return 0;
300
301 err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_RED,
302 &hw_stats);
303 if (err == -EOPNOTSUPP)
304 return 0;
305
306 if (!err)
307 sch->flags |= TCQ_F_OFFLOADED;
308
309 return err;
310}
311
312static int red_dump(struct Qdisc *sch, struct sk_buff *skb)
313{
314 struct red_sched_data *q = qdisc_priv(sch);
315 struct nlattr *opts = NULL;
316 struct tc_red_qopt opt = {
317 .limit = q->limit,
318 .flags = q->flags,
319 .qth_min = q->parms.qth_min >> q->parms.Wlog,
320 .qth_max = q->parms.qth_max >> q->parms.Wlog,
321 .Wlog = q->parms.Wlog,
322 .Plog = q->parms.Plog,
323 .Scell_log = q->parms.Scell_log,
324 };
325 int err;
326
327 err = red_dump_offload_stats(sch, &opt);
328 if (err)
329 goto nla_put_failure;
330
331 opts = nla_nest_start(skb, TCA_OPTIONS);
332 if (opts == NULL)
333 goto nla_put_failure;
334 if (nla_put(skb, TCA_RED_PARMS, sizeof(opt), &opt) ||
335 nla_put_u32(skb, TCA_RED_MAX_P, q->parms.max_P))
336 goto nla_put_failure;
337 return nla_nest_end(skb, opts);
338
339nla_put_failure:
340 nla_nest_cancel(skb, opts);
341 return -EMSGSIZE;
342}
343
344static int red_dump_stats(struct Qdisc *sch, struct gnet_dump *d)
345{
346 struct red_sched_data *q = qdisc_priv(sch);
347 struct net_device *dev = qdisc_dev(sch);
348 struct tc_red_xstats st = {0};
349
350 if (sch->flags & TCQ_F_OFFLOADED) {
351 struct tc_red_qopt_offload hw_stats_request = {
352 .command = TC_RED_XSTATS,
353 .handle = sch->handle,
354 .parent = sch->parent,
355 {
356 .xstats = &q->stats,
357 },
358 };
359 dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_RED,
360 &hw_stats_request);
361 }
362 st.early = q->stats.prob_drop + q->stats.forced_drop;
363 st.pdrop = q->stats.pdrop;
364 st.other = q->stats.other;
365 st.marked = q->stats.prob_mark + q->stats.forced_mark;
366
367 return gnet_stats_copy_app(d, &st, sizeof(st));
368}
369
370static int red_dump_class(struct Qdisc *sch, unsigned long cl,
371 struct sk_buff *skb, struct tcmsg *tcm)
372{
373 struct red_sched_data *q = qdisc_priv(sch);
374
375 tcm->tcm_handle |= TC_H_MIN(1);
376 tcm->tcm_info = q->qdisc->handle;
377 return 0;
378}
379
380static int red_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
381 struct Qdisc **old, struct netlink_ext_ack *extack)
382{
383 struct red_sched_data *q = qdisc_priv(sch);
384
385 if (new == NULL)
386 new = &noop_qdisc;
387
388 *old = qdisc_replace(sch, new, &q->qdisc);
389 return 0;
390}
391
392static struct Qdisc *red_leaf(struct Qdisc *sch, unsigned long arg)
393{
394 struct red_sched_data *q = qdisc_priv(sch);
395 return q->qdisc;
396}
397
398static unsigned long red_find(struct Qdisc *sch, u32 classid)
399{
400 return 1;
401}
402
403static void red_walk(struct Qdisc *sch, struct qdisc_walker *walker)
404{
405 if (!walker->stop) {
406 if (walker->count >= walker->skip)
407 if (walker->fn(sch, 1, walker) < 0) {
408 walker->stop = 1;
409 return;
410 }
411 walker->count++;
412 }
413}
414
415static const struct Qdisc_class_ops red_class_ops = {
416 .graft = red_graft,
417 .leaf = red_leaf,
418 .find = red_find,
419 .walk = red_walk,
420 .dump = red_dump_class,
421};
422
423static struct Qdisc_ops red_qdisc_ops __read_mostly = {
424 .id = "red",
425 .priv_size = sizeof(struct red_sched_data),
426 .cl_ops = &red_class_ops,
427 .enqueue = red_enqueue,
428 .dequeue = red_dequeue,
429 .peek = red_peek,
430 .init = red_init,
431 .reset = red_reset,
432 .destroy = red_destroy,
433 .change = red_change,
434 .dump = red_dump,
435 .dump_stats = red_dump_stats,
436 .owner = THIS_MODULE,
437};
438
439static int __init red_module_init(void)
440{
441 return register_qdisc(&red_qdisc_ops);
442}
443
444static void __exit red_module_exit(void)
445{
446 unregister_qdisc(&red_qdisc_ops);
447}
448
449module_init(red_module_init)
450module_exit(red_module_exit)
451
452MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * net/sched/sch_red.c Random Early Detection queue.
4 *
5 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
6 *
7 * Changes:
8 * J Hadi Salim 980914: computation fixes
9 * Alexey Makarenko <makar@phoenix.kharkov.ua> 990814: qave on idle link was calculated incorrectly.
10 * J Hadi Salim 980816: ECN support
11 */
12
13#include <linux/module.h>
14#include <linux/types.h>
15#include <linux/kernel.h>
16#include <linux/skbuff.h>
17#include <net/pkt_sched.h>
18#include <net/pkt_cls.h>
19#include <net/inet_ecn.h>
20#include <net/red.h>
21
22
23/* Parameters, settable by user:
24 -----------------------------
25
26 limit - bytes (must be > qth_max + burst)
27
28 Hard limit on queue length, should be chosen >qth_max
29 to allow packet bursts. This parameter does not
30 affect the algorithms behaviour and can be chosen
31 arbitrarily high (well, less than ram size)
32 Really, this limit will never be reached
33 if RED works correctly.
34 */
35
36struct red_sched_data {
37 u32 limit; /* HARD maximal queue length */
38 unsigned char flags;
39 struct timer_list adapt_timer;
40 struct Qdisc *sch;
41 struct red_parms parms;
42 struct red_vars vars;
43 struct red_stats stats;
44 struct Qdisc *qdisc;
45};
46
47static inline int red_use_ecn(struct red_sched_data *q)
48{
49 return q->flags & TC_RED_ECN;
50}
51
52static inline int red_use_harddrop(struct red_sched_data *q)
53{
54 return q->flags & TC_RED_HARDDROP;
55}
56
57static int red_enqueue(struct sk_buff *skb, struct Qdisc *sch,
58 struct sk_buff **to_free)
59{
60 struct red_sched_data *q = qdisc_priv(sch);
61 struct Qdisc *child = q->qdisc;
62 int ret;
63
64 q->vars.qavg = red_calc_qavg(&q->parms,
65 &q->vars,
66 child->qstats.backlog);
67
68 if (red_is_idling(&q->vars))
69 red_end_of_idle_period(&q->vars);
70
71 switch (red_action(&q->parms, &q->vars, q->vars.qavg)) {
72 case RED_DONT_MARK:
73 break;
74
75 case RED_PROB_MARK:
76 qdisc_qstats_overlimit(sch);
77 if (!red_use_ecn(q) || !INET_ECN_set_ce(skb)) {
78 q->stats.prob_drop++;
79 goto congestion_drop;
80 }
81
82 q->stats.prob_mark++;
83 break;
84
85 case RED_HARD_MARK:
86 qdisc_qstats_overlimit(sch);
87 if (red_use_harddrop(q) || !red_use_ecn(q) ||
88 !INET_ECN_set_ce(skb)) {
89 q->stats.forced_drop++;
90 goto congestion_drop;
91 }
92
93 q->stats.forced_mark++;
94 break;
95 }
96
97 ret = qdisc_enqueue(skb, child, to_free);
98 if (likely(ret == NET_XMIT_SUCCESS)) {
99 qdisc_qstats_backlog_inc(sch, skb);
100 sch->q.qlen++;
101 } else if (net_xmit_drop_count(ret)) {
102 q->stats.pdrop++;
103 qdisc_qstats_drop(sch);
104 }
105 return ret;
106
107congestion_drop:
108 qdisc_drop(skb, sch, to_free);
109 return NET_XMIT_CN;
110}
111
112static struct sk_buff *red_dequeue(struct Qdisc *sch)
113{
114 struct sk_buff *skb;
115 struct red_sched_data *q = qdisc_priv(sch);
116 struct Qdisc *child = q->qdisc;
117
118 skb = child->dequeue(child);
119 if (skb) {
120 qdisc_bstats_update(sch, skb);
121 qdisc_qstats_backlog_dec(sch, skb);
122 sch->q.qlen--;
123 } else {
124 if (!red_is_idling(&q->vars))
125 red_start_of_idle_period(&q->vars);
126 }
127 return skb;
128}
129
130static struct sk_buff *red_peek(struct Qdisc *sch)
131{
132 struct red_sched_data *q = qdisc_priv(sch);
133 struct Qdisc *child = q->qdisc;
134
135 return child->ops->peek(child);
136}
137
138static void red_reset(struct Qdisc *sch)
139{
140 struct red_sched_data *q = qdisc_priv(sch);
141
142 qdisc_reset(q->qdisc);
143 sch->qstats.backlog = 0;
144 sch->q.qlen = 0;
145 red_restart(&q->vars);
146}
147
148static int red_offload(struct Qdisc *sch, bool enable)
149{
150 struct red_sched_data *q = qdisc_priv(sch);
151 struct net_device *dev = qdisc_dev(sch);
152 struct tc_red_qopt_offload opt = {
153 .handle = sch->handle,
154 .parent = sch->parent,
155 };
156
157 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
158 return -EOPNOTSUPP;
159
160 if (enable) {
161 opt.command = TC_RED_REPLACE;
162 opt.set.min = q->parms.qth_min >> q->parms.Wlog;
163 opt.set.max = q->parms.qth_max >> q->parms.Wlog;
164 opt.set.probability = q->parms.max_P;
165 opt.set.limit = q->limit;
166 opt.set.is_ecn = red_use_ecn(q);
167 opt.set.is_harddrop = red_use_harddrop(q);
168 opt.set.qstats = &sch->qstats;
169 } else {
170 opt.command = TC_RED_DESTROY;
171 }
172
173 return dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_RED, &opt);
174}
175
176static void red_destroy(struct Qdisc *sch)
177{
178 struct red_sched_data *q = qdisc_priv(sch);
179
180 del_timer_sync(&q->adapt_timer);
181 red_offload(sch, false);
182 qdisc_put(q->qdisc);
183}
184
185static const struct nla_policy red_policy[TCA_RED_MAX + 1] = {
186 [TCA_RED_PARMS] = { .len = sizeof(struct tc_red_qopt) },
187 [TCA_RED_STAB] = { .len = RED_STAB_SIZE },
188 [TCA_RED_MAX_P] = { .type = NLA_U32 },
189};
190
191static int red_change(struct Qdisc *sch, struct nlattr *opt,
192 struct netlink_ext_ack *extack)
193{
194 struct Qdisc *old_child = NULL, *child = NULL;
195 struct red_sched_data *q = qdisc_priv(sch);
196 struct nlattr *tb[TCA_RED_MAX + 1];
197 struct tc_red_qopt *ctl;
198 int err;
199 u32 max_P;
200
201 if (opt == NULL)
202 return -EINVAL;
203
204 err = nla_parse_nested_deprecated(tb, TCA_RED_MAX, opt, red_policy,
205 NULL);
206 if (err < 0)
207 return err;
208
209 if (tb[TCA_RED_PARMS] == NULL ||
210 tb[TCA_RED_STAB] == NULL)
211 return -EINVAL;
212
213 max_P = tb[TCA_RED_MAX_P] ? nla_get_u32(tb[TCA_RED_MAX_P]) : 0;
214
215 ctl = nla_data(tb[TCA_RED_PARMS]);
216 if (!red_check_params(ctl->qth_min, ctl->qth_max, ctl->Wlog))
217 return -EINVAL;
218
219 if (ctl->limit > 0) {
220 child = fifo_create_dflt(sch, &bfifo_qdisc_ops, ctl->limit,
221 extack);
222 if (IS_ERR(child))
223 return PTR_ERR(child);
224
225 /* child is fifo, no need to check for noop_qdisc */
226 qdisc_hash_add(child, true);
227 }
228
229 sch_tree_lock(sch);
230 q->flags = ctl->flags;
231 q->limit = ctl->limit;
232 if (child) {
233 qdisc_tree_flush_backlog(q->qdisc);
234 old_child = q->qdisc;
235 q->qdisc = child;
236 }
237
238 red_set_parms(&q->parms,
239 ctl->qth_min, ctl->qth_max, ctl->Wlog,
240 ctl->Plog, ctl->Scell_log,
241 nla_data(tb[TCA_RED_STAB]),
242 max_P);
243 red_set_vars(&q->vars);
244
245 del_timer(&q->adapt_timer);
246 if (ctl->flags & TC_RED_ADAPTATIVE)
247 mod_timer(&q->adapt_timer, jiffies + HZ/2);
248
249 if (!q->qdisc->q.qlen)
250 red_start_of_idle_period(&q->vars);
251
252 sch_tree_unlock(sch);
253
254 red_offload(sch, true);
255
256 if (old_child)
257 qdisc_put(old_child);
258 return 0;
259}
260
261static inline void red_adaptative_timer(struct timer_list *t)
262{
263 struct red_sched_data *q = from_timer(q, t, adapt_timer);
264 struct Qdisc *sch = q->sch;
265 spinlock_t *root_lock = qdisc_lock(qdisc_root_sleeping(sch));
266
267 spin_lock(root_lock);
268 red_adaptative_algo(&q->parms, &q->vars);
269 mod_timer(&q->adapt_timer, jiffies + HZ/2);
270 spin_unlock(root_lock);
271}
272
273static int red_init(struct Qdisc *sch, struct nlattr *opt,
274 struct netlink_ext_ack *extack)
275{
276 struct red_sched_data *q = qdisc_priv(sch);
277
278 q->qdisc = &noop_qdisc;
279 q->sch = sch;
280 timer_setup(&q->adapt_timer, red_adaptative_timer, 0);
281 return red_change(sch, opt, extack);
282}
283
284static int red_dump_offload_stats(struct Qdisc *sch)
285{
286 struct tc_red_qopt_offload hw_stats = {
287 .command = TC_RED_STATS,
288 .handle = sch->handle,
289 .parent = sch->parent,
290 {
291 .stats.bstats = &sch->bstats,
292 .stats.qstats = &sch->qstats,
293 },
294 };
295
296 return qdisc_offload_dump_helper(sch, TC_SETUP_QDISC_RED, &hw_stats);
297}
298
299static int red_dump(struct Qdisc *sch, struct sk_buff *skb)
300{
301 struct red_sched_data *q = qdisc_priv(sch);
302 struct nlattr *opts = NULL;
303 struct tc_red_qopt opt = {
304 .limit = q->limit,
305 .flags = q->flags,
306 .qth_min = q->parms.qth_min >> q->parms.Wlog,
307 .qth_max = q->parms.qth_max >> q->parms.Wlog,
308 .Wlog = q->parms.Wlog,
309 .Plog = q->parms.Plog,
310 .Scell_log = q->parms.Scell_log,
311 };
312 int err;
313
314 err = red_dump_offload_stats(sch);
315 if (err)
316 goto nla_put_failure;
317
318 opts = nla_nest_start_noflag(skb, TCA_OPTIONS);
319 if (opts == NULL)
320 goto nla_put_failure;
321 if (nla_put(skb, TCA_RED_PARMS, sizeof(opt), &opt) ||
322 nla_put_u32(skb, TCA_RED_MAX_P, q->parms.max_P))
323 goto nla_put_failure;
324 return nla_nest_end(skb, opts);
325
326nla_put_failure:
327 nla_nest_cancel(skb, opts);
328 return -EMSGSIZE;
329}
330
331static int red_dump_stats(struct Qdisc *sch, struct gnet_dump *d)
332{
333 struct red_sched_data *q = qdisc_priv(sch);
334 struct net_device *dev = qdisc_dev(sch);
335 struct tc_red_xstats st = {0};
336
337 if (sch->flags & TCQ_F_OFFLOADED) {
338 struct tc_red_qopt_offload hw_stats_request = {
339 .command = TC_RED_XSTATS,
340 .handle = sch->handle,
341 .parent = sch->parent,
342 {
343 .xstats = &q->stats,
344 },
345 };
346 dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_RED,
347 &hw_stats_request);
348 }
349 st.early = q->stats.prob_drop + q->stats.forced_drop;
350 st.pdrop = q->stats.pdrop;
351 st.other = q->stats.other;
352 st.marked = q->stats.prob_mark + q->stats.forced_mark;
353
354 return gnet_stats_copy_app(d, &st, sizeof(st));
355}
356
357static int red_dump_class(struct Qdisc *sch, unsigned long cl,
358 struct sk_buff *skb, struct tcmsg *tcm)
359{
360 struct red_sched_data *q = qdisc_priv(sch);
361
362 tcm->tcm_handle |= TC_H_MIN(1);
363 tcm->tcm_info = q->qdisc->handle;
364 return 0;
365}
366
367static void red_graft_offload(struct Qdisc *sch,
368 struct Qdisc *new, struct Qdisc *old,
369 struct netlink_ext_ack *extack)
370{
371 struct tc_red_qopt_offload graft_offload = {
372 .handle = sch->handle,
373 .parent = sch->parent,
374 .child_handle = new->handle,
375 .command = TC_RED_GRAFT,
376 };
377
378 qdisc_offload_graft_helper(qdisc_dev(sch), sch, new, old,
379 TC_SETUP_QDISC_RED, &graft_offload, extack);
380}
381
382static int red_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
383 struct Qdisc **old, struct netlink_ext_ack *extack)
384{
385 struct red_sched_data *q = qdisc_priv(sch);
386
387 if (new == NULL)
388 new = &noop_qdisc;
389
390 *old = qdisc_replace(sch, new, &q->qdisc);
391
392 red_graft_offload(sch, new, *old, extack);
393 return 0;
394}
395
396static struct Qdisc *red_leaf(struct Qdisc *sch, unsigned long arg)
397{
398 struct red_sched_data *q = qdisc_priv(sch);
399 return q->qdisc;
400}
401
402static unsigned long red_find(struct Qdisc *sch, u32 classid)
403{
404 return 1;
405}
406
407static void red_walk(struct Qdisc *sch, struct qdisc_walker *walker)
408{
409 if (!walker->stop) {
410 if (walker->count >= walker->skip)
411 if (walker->fn(sch, 1, walker) < 0) {
412 walker->stop = 1;
413 return;
414 }
415 walker->count++;
416 }
417}
418
419static const struct Qdisc_class_ops red_class_ops = {
420 .graft = red_graft,
421 .leaf = red_leaf,
422 .find = red_find,
423 .walk = red_walk,
424 .dump = red_dump_class,
425};
426
427static struct Qdisc_ops red_qdisc_ops __read_mostly = {
428 .id = "red",
429 .priv_size = sizeof(struct red_sched_data),
430 .cl_ops = &red_class_ops,
431 .enqueue = red_enqueue,
432 .dequeue = red_dequeue,
433 .peek = red_peek,
434 .init = red_init,
435 .reset = red_reset,
436 .destroy = red_destroy,
437 .change = red_change,
438 .dump = red_dump,
439 .dump_stats = red_dump_stats,
440 .owner = THIS_MODULE,
441};
442
443static int __init red_module_init(void)
444{
445 return register_qdisc(&red_qdisc_ops);
446}
447
448static void __exit red_module_exit(void)
449{
450 unregister_qdisc(&red_qdisc_ops);
451}
452
453module_init(red_module_init)
454module_exit(red_module_exit)
455
456MODULE_LICENSE("GPL");