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-rw-r--r--include/linux/pkt_sched.h26
-rw-r--r--include/net/codel.h332
-rw-r--r--net/sched/Kconfig11
-rw-r--r--net/sched/Makefile1
-rw-r--r--net/sched/sch_codel.c275
5 files changed, 645 insertions, 0 deletions
diff --git a/include/linux/pkt_sched.h b/include/linux/pkt_sched.h
index ffe975c3f1d8..cde56c22bdab 100644
--- a/include/linux/pkt_sched.h
+++ b/include/linux/pkt_sched.h
@@ -655,4 +655,30 @@ struct tc_qfq_stats {
655 __u32 lmax; 655 __u32 lmax;
656}; 656};
657 657
658/* CODEL */
659
660enum {
661 TCA_CODEL_UNSPEC,
662 TCA_CODEL_TARGET,
663 TCA_CODEL_LIMIT,
664 TCA_CODEL_INTERVAL,
665 TCA_CODEL_ECN,
666 __TCA_CODEL_MAX
667};
668
669#define TCA_CODEL_MAX (__TCA_CODEL_MAX - 1)
670
671struct tc_codel_xstats {
672 __u32 maxpacket; /* largest packet we've seen so far */
673 __u32 count; /* how many drops we've done since the last time we
674 * entered dropping state
675 */
676 __u32 lastcount; /* count at entry to dropping state */
677 __u32 ldelay; /* in-queue delay seen by most recently dequeued packet */
678 __s32 drop_next; /* time to drop next packet */
679 __u32 drop_overlimit; /* number of time max qdisc packet limit was hit */
680 __u32 ecn_mark; /* number of packets we ECN marked instead of dropped */
681 __u32 dropping; /* are we in dropping state ? */
682};
683
658#endif 684#endif
diff --git a/include/net/codel.h b/include/net/codel.h
new file mode 100644
index 000000000000..bce2cefa8c94
--- /dev/null
+++ b/include/net/codel.h
@@ -0,0 +1,332 @@
1#ifndef __NET_SCHED_CODEL_H
2#define __NET_SCHED_CODEL_H
3
4/*
5 * Codel - The Controlled-Delay Active Queue Management algorithm
6 *
7 * Copyright (C) 2011-2012 Kathleen Nichols <nichols@pollere.com>
8 * Copyright (C) 2011-2012 Van Jacobson <van@pollere.net>
9 * Copyright (C) 2012 Michael D. Taht <dave.taht@bufferbloat.net>
10 * Copyright (C) 2012 Eric Dumazet <edumazet@google.com>
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions, and the following disclaimer,
17 * without modification.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. The names of the authors may not be used to endorse or promote products
22 * derived from this software without specific prior written permission.
23 *
24 * Alternatively, provided that this notice is retained in full, this
25 * software may be distributed under the terms of the GNU General
26 * Public License ("GPL") version 2, in which case the provisions of the
27 * GPL apply INSTEAD OF those given above.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
30 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
31 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
32 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
33 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
34 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
40 * DAMAGE.
41 *
42 */
43
44#include <linux/types.h>
45#include <linux/ktime.h>
46#include <linux/skbuff.h>
47#include <net/pkt_sched.h>
48#include <net/inet_ecn.h>
49
50/* Controlling Queue Delay (CoDel) algorithm
51 * =========================================
52 * Source : Kathleen Nichols and Van Jacobson
53 * http://queue.acm.org/detail.cfm?id=2209336
54 *
55 * Implemented on linux by Dave Taht and Eric Dumazet
56 */
57
58
59/* CoDel uses a 1024 nsec clock, encoded in u32
60 * This gives a range of 2199 seconds, because of signed compares
61 */
62typedef u32 codel_time_t;
63typedef s32 codel_tdiff_t;
64#define CODEL_SHIFT 10
65#define MS2TIME(a) ((a * NSEC_PER_MSEC) >> CODEL_SHIFT)
66
67static inline codel_time_t codel_get_time(void)
68{
69 u64 ns = ktime_to_ns(ktime_get());
70
71 return ns >> CODEL_SHIFT;
72}
73
74#define codel_time_after(a, b) ((s32)(a) - (s32)(b) > 0)
75#define codel_time_after_eq(a, b) ((s32)(a) - (s32)(b) >= 0)
76#define codel_time_before(a, b) ((s32)(a) - (s32)(b) < 0)
77#define codel_time_before_eq(a, b) ((s32)(a) - (s32)(b) <= 0)
78
79/* Qdiscs using codel plugin must use codel_skb_cb in their own cb[] */
80struct codel_skb_cb {
81 codel_time_t enqueue_time;
82};
83
84static struct codel_skb_cb *get_codel_cb(const struct sk_buff *skb)
85{
86 qdisc_cb_private_validate(skb, sizeof(struct codel_skb_cb));
87 return (struct codel_skb_cb *)qdisc_skb_cb(skb)->data;
88}
89
90static codel_time_t codel_get_enqueue_time(const struct sk_buff *skb)
91{
92 return get_codel_cb(skb)->enqueue_time;
93}
94
95static void codel_set_enqueue_time(struct sk_buff *skb)
96{
97 get_codel_cb(skb)->enqueue_time = codel_get_time();
98}
99
100static inline u32 codel_time_to_us(codel_time_t val)
101{
102 u64 valns = ((u64)val << CODEL_SHIFT);
103
104 do_div(valns, NSEC_PER_USEC);
105 return (u32)valns;
106}
107
108/**
109 * struct codel_params - contains codel parameters
110 * @target: target queue size (in time units)
111 * @interval: width of moving time window
112 * @ecn: is Explicit Congestion Notification enabled
113 */
114struct codel_params {
115 codel_time_t target;
116 codel_time_t interval;
117 bool ecn;
118};
119
120/**
121 * struct codel_vars - contains codel variables
122 * @count: how many drops we've done since the last time we
123 * entered dropping state
124 * @lastcount: count at entry to dropping state
125 * @dropping: set to true if in dropping state
126 * @first_above_time: when we went (or will go) continuously above target
127 * for interval
128 * @drop_next: time to drop next packet, or when we dropped last
129 * @ldelay: sojourn time of last dequeued packet
130 */
131struct codel_vars {
132 u32 count;
133 u32 lastcount;
134 bool dropping;
135 codel_time_t first_above_time;
136 codel_time_t drop_next;
137 codel_time_t ldelay;
138};
139
140/**
141 * struct codel_stats - contains codel shared variables and stats
142 * @maxpacket: largest packet we've seen so far
143 * @drop_count: temp count of dropped packets in dequeue()
144 * ecn_mark: number of packets we ECN marked instead of dropping
145 */
146struct codel_stats {
147 u32 maxpacket;
148 u32 drop_count;
149 u32 ecn_mark;
150};
151
152static void codel_params_init(struct codel_params *params)
153{
154 params->interval = MS2TIME(100);
155 params->target = MS2TIME(5);
156 params->ecn = false;
157}
158
159static void codel_vars_init(struct codel_vars *vars)
160{
161 vars->drop_next = 0;
162 vars->first_above_time = 0;
163 vars->dropping = false; /* exit dropping state */
164 vars->count = 0;
165 vars->lastcount = 0;
166}
167
168static void codel_stats_init(struct codel_stats *stats)
169{
170 stats->maxpacket = 256;
171}
172
173/* return interval/sqrt(x) with good precision
174 * relies on int_sqrt(unsigned long x) kernel implementation
175 */
176static u32 codel_inv_sqrt(u32 _interval, u32 _x)
177{
178 u64 interval = _interval;
179 unsigned long x = _x;
180
181 /* Scale operands for max precision */
182
183#if BITS_PER_LONG == 64
184 x <<= 32; /* On 64bit arches, we can prescale x by 32bits */
185 interval <<= 16;
186#endif
187
188 while (x < (1UL << (BITS_PER_LONG - 2))) {
189 x <<= 2;
190 interval <<= 1;
191 }
192 do_div(interval, int_sqrt(x));
193 return (u32)interval;
194}
195
196static codel_time_t codel_control_law(codel_time_t t,
197 codel_time_t interval,
198 u32 count)
199{
200 return t + codel_inv_sqrt(interval, count);
201}
202
203
204static bool codel_should_drop(struct sk_buff *skb,
205 unsigned int *backlog,
206 struct codel_vars *vars,
207 struct codel_params *params,
208 struct codel_stats *stats,
209 codel_time_t now)
210{
211 bool ok_to_drop;
212
213 if (!skb) {
214 vars->first_above_time = 0;
215 return false;
216 }
217
218 vars->ldelay = now - codel_get_enqueue_time(skb);
219 *backlog -= qdisc_pkt_len(skb);
220
221 if (unlikely(qdisc_pkt_len(skb) > stats->maxpacket))
222 stats->maxpacket = qdisc_pkt_len(skb);
223
224 if (codel_time_before(vars->ldelay, params->target) ||
225 *backlog <= stats->maxpacket) {
226 /* went below - stay below for at least interval */
227 vars->first_above_time = 0;
228 return false;
229 }
230 ok_to_drop = false;
231 if (vars->first_above_time == 0) {
232 /* just went above from below. If we stay above
233 * for at least interval we'll say it's ok to drop
234 */
235 vars->first_above_time = now + params->interval;
236 } else if (codel_time_after(now, vars->first_above_time)) {
237 ok_to_drop = true;
238 }
239 return ok_to_drop;
240}
241
242typedef struct sk_buff * (*codel_skb_dequeue_t)(struct codel_vars *vars,
243 struct Qdisc *sch);
244
245static struct sk_buff *codel_dequeue(struct Qdisc *sch,
246 struct codel_params *params,
247 struct codel_vars *vars,
248 struct codel_stats *stats,
249 codel_skb_dequeue_t dequeue_func,
250 u32 *backlog)
251{
252 struct sk_buff *skb = dequeue_func(vars, sch);
253 codel_time_t now;
254 bool drop;
255
256 if (!skb) {
257 vars->dropping = false;
258 return skb;
259 }
260 now = codel_get_time();
261 drop = codel_should_drop(skb, backlog, vars, params, stats, now);
262 if (vars->dropping) {
263 if (!drop) {
264 /* sojourn time below target - leave dropping state */
265 vars->dropping = false;
266 } else if (codel_time_after_eq(now, vars->drop_next)) {
267 /* It's time for the next drop. Drop the current
268 * packet and dequeue the next. The dequeue might
269 * take us out of dropping state.
270 * If not, schedule the next drop.
271 * A large backlog might result in drop rates so high
272 * that the next drop should happen now,
273 * hence the while loop.
274 */
275 while (vars->dropping &&
276 codel_time_after_eq(now, vars->drop_next)) {
277 if (++vars->count == 0) /* avoid zero divides */
278 vars->count = ~0U;
279 if (params->ecn && INET_ECN_set_ce(skb)) {
280 stats->ecn_mark++;
281 vars->drop_next =
282 codel_control_law(vars->drop_next,
283 params->interval,
284 vars->count);
285 goto end;
286 }
287 qdisc_drop(skb, sch);
288 stats->drop_count++;
289 skb = dequeue_func(vars, sch);
290 if (!codel_should_drop(skb, backlog,
291 vars, params, stats, now)) {
292 /* leave dropping state */
293 vars->dropping = false;
294 } else {
295 /* and schedule the next drop */
296 vars->drop_next =
297 codel_control_law(vars->drop_next,
298 params->interval,
299 vars->count);
300 }
301 }
302 }
303 } else if (drop) {
304 if (params->ecn && INET_ECN_set_ce(skb)) {
305 stats->ecn_mark++;
306 } else {
307 qdisc_drop(skb, sch);
308 stats->drop_count++;
309
310 skb = dequeue_func(vars, sch);
311 drop = codel_should_drop(skb, backlog, vars, params,
312 stats, now);
313 }
314 vars->dropping = true;
315 /* if min went above target close to when we last went below it
316 * assume that the drop rate that controlled the queue on the
317 * last cycle is a good starting point to control it now.
318 */
319 if (codel_time_before(now - vars->drop_next,
320 16 * params->interval)) {
321 vars->count = (vars->count - vars->lastcount) | 1;
322 } else {
323 vars->count = 1;
324 }
325 vars->lastcount = vars->count;
326 vars->drop_next = codel_control_law(now, params->interval,
327 vars->count);
328 }
329end:
330 return skb;
331}
332#endif
diff --git a/net/sched/Kconfig b/net/sched/Kconfig
index 75b58f81d53d..fadd2522053d 100644
--- a/net/sched/Kconfig
+++ b/net/sched/Kconfig
@@ -250,6 +250,17 @@ config NET_SCH_QFQ
250 250
251 If unsure, say N. 251 If unsure, say N.
252 252
253config NET_SCH_CODEL
254 tristate "Controlled Delay AQM (CODEL)"
255 help
256 Say Y here if you want to use the Controlled Delay (CODEL)
257 packet scheduling algorithm.
258
259 To compile this driver as a module, choose M here: the module
260 will be called sch_codel.
261
262 If unsure, say N.
263
253config NET_SCH_INGRESS 264config NET_SCH_INGRESS
254 tristate "Ingress Qdisc" 265 tristate "Ingress Qdisc"
255 depends on NET_CLS_ACT 266 depends on NET_CLS_ACT
diff --git a/net/sched/Makefile b/net/sched/Makefile
index 8cdf4e2b51d3..30fab03b8516 100644
--- a/net/sched/Makefile
+++ b/net/sched/Makefile
@@ -37,6 +37,7 @@ obj-$(CONFIG_NET_SCH_PLUG) += sch_plug.o
37obj-$(CONFIG_NET_SCH_MQPRIO) += sch_mqprio.o 37obj-$(CONFIG_NET_SCH_MQPRIO) += sch_mqprio.o
38obj-$(CONFIG_NET_SCH_CHOKE) += sch_choke.o 38obj-$(CONFIG_NET_SCH_CHOKE) += sch_choke.o
39obj-$(CONFIG_NET_SCH_QFQ) += sch_qfq.o 39obj-$(CONFIG_NET_SCH_QFQ) += sch_qfq.o
40obj-$(CONFIG_NET_SCH_CODEL) += sch_codel.o
40 41
41obj-$(CONFIG_NET_CLS_U32) += cls_u32.o 42obj-$(CONFIG_NET_CLS_U32) += cls_u32.o
42obj-$(CONFIG_NET_CLS_ROUTE4) += cls_route.o 43obj-$(CONFIG_NET_CLS_ROUTE4) += cls_route.o
diff --git a/net/sched/sch_codel.c b/net/sched/sch_codel.c
new file mode 100644
index 000000000000..b4a1a81e757e
--- /dev/null
+++ b/net/sched/sch_codel.c
@@ -0,0 +1,275 @@
1/*
2 * Codel - The Controlled-Delay Active Queue Management algorithm
3 *
4 * Copyright (C) 2011-2012 Kathleen Nichols <nichols@pollere.com>
5 * Copyright (C) 2011-2012 Van Jacobson <van@pollere.net>
6 *
7 * Implemented on linux by :
8 * Copyright (C) 2012 Michael D. Taht <dave.taht@bufferbloat.net>
9 * Copyright (C) 2012 Eric Dumazet <edumazet@google.com>
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions, and the following disclaimer,
16 * without modification.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. The names of the authors may not be used to endorse or promote products
21 * derived from this software without specific prior written permission.
22 *
23 * Alternatively, provided that this notice is retained in full, this
24 * software may be distributed under the terms of the GNU General
25 * Public License ("GPL") version 2, in which case the provisions of the
26 * GPL apply INSTEAD OF those given above.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
39 * DAMAGE.
40 *
41 */
42
43#include <linux/module.h>
44#include <linux/slab.h>
45#include <linux/types.h>
46#include <linux/kernel.h>
47#include <linux/errno.h>
48#include <linux/skbuff.h>
49#include <net/pkt_sched.h>
50#include <net/codel.h>
51
52
53#define DEFAULT_CODEL_LIMIT 1000
54
55struct codel_sched_data {
56 struct codel_params params;
57 struct codel_vars vars;
58 struct codel_stats stats;
59 u32 drop_overlimit;
60};
61
62/* This is the specific function called from codel_dequeue()
63 * to dequeue a packet from queue. Note: backlog is handled in
64 * codel, we dont need to reduce it here.
65 */
66static struct sk_buff *dequeue(struct codel_vars *vars, struct Qdisc *sch)
67{
68 struct sk_buff *skb = __skb_dequeue(&sch->q);
69
70 prefetch(&skb->end); /* we'll need skb_shinfo() */
71 return skb;
72}
73
74static struct sk_buff *codel_qdisc_dequeue(struct Qdisc *sch)
75{
76 struct codel_sched_data *q = qdisc_priv(sch);
77 struct sk_buff *skb;
78
79 skb = codel_dequeue(sch, &q->params, &q->vars, &q->stats,
80 dequeue, &sch->qstats.backlog);
81 /* We cant call qdisc_tree_decrease_qlen() if our qlen is 0,
82 * or HTB crashes. Defer it for next round.
83 */
84 if (q->stats.drop_count && sch->q.qlen) {
85 qdisc_tree_decrease_qlen(sch, q->stats.drop_count);
86 q->stats.drop_count = 0;
87 }
88 if (skb)
89 qdisc_bstats_update(sch, skb);
90 return skb;
91}
92
93static int codel_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
94{
95 struct codel_sched_data *q;
96
97 if (likely(qdisc_qlen(sch) < sch->limit)) {
98 codel_set_enqueue_time(skb);
99 return qdisc_enqueue_tail(skb, sch);
100 }
101 q = qdisc_priv(sch);
102 q->drop_overlimit++;
103 return qdisc_drop(skb, sch);
104}
105
106static const struct nla_policy codel_policy[TCA_CODEL_MAX + 1] = {
107 [TCA_CODEL_TARGET] = { .type = NLA_U32 },
108 [TCA_CODEL_LIMIT] = { .type = NLA_U32 },
109 [TCA_CODEL_INTERVAL] = { .type = NLA_U32 },
110 [TCA_CODEL_ECN] = { .type = NLA_U32 },
111};
112
113static int codel_change(struct Qdisc *sch, struct nlattr *opt)
114{
115 struct codel_sched_data *q = qdisc_priv(sch);
116 struct nlattr *tb[TCA_CODEL_MAX + 1];
117 unsigned int qlen;
118 int err;
119
120 if (!opt)
121 return -EINVAL;
122
123 err = nla_parse_nested(tb, TCA_CODEL_MAX, opt, codel_policy);
124 if (err < 0)
125 return err;
126
127 sch_tree_lock(sch);
128
129 if (tb[TCA_CODEL_TARGET]) {
130 u32 target = nla_get_u32(tb[TCA_CODEL_TARGET]);
131
132 q->params.target = ((u64)target * NSEC_PER_USEC) >> CODEL_SHIFT;
133 }
134
135 if (tb[TCA_CODEL_INTERVAL]) {
136 u32 interval = nla_get_u32(tb[TCA_CODEL_INTERVAL]);
137
138 q->params.interval = ((u64)interval * NSEC_PER_USEC) >> CODEL_SHIFT;
139 }
140
141 if (tb[TCA_CODEL_LIMIT])
142 sch->limit = nla_get_u32(tb[TCA_CODEL_LIMIT]);
143
144 if (tb[TCA_CODEL_ECN])
145 q->params.ecn = !!nla_get_u32(tb[TCA_CODEL_ECN]);
146
147 qlen = sch->q.qlen;
148 while (sch->q.qlen > sch->limit) {
149 struct sk_buff *skb = __skb_dequeue(&sch->q);
150
151 sch->qstats.backlog -= qdisc_pkt_len(skb);
152 qdisc_drop(skb, sch);
153 }
154 qdisc_tree_decrease_qlen(sch, qlen - sch->q.qlen);
155
156 sch_tree_unlock(sch);
157 return 0;
158}
159
160static int codel_init(struct Qdisc *sch, struct nlattr *opt)
161{
162 struct codel_sched_data *q = qdisc_priv(sch);
163
164 sch->limit = DEFAULT_CODEL_LIMIT;
165
166 codel_params_init(&q->params);
167 codel_vars_init(&q->vars);
168 codel_stats_init(&q->stats);
169
170 if (opt) {
171 int err = codel_change(sch, opt);
172
173 if (err)
174 return err;
175 }
176
177 if (sch->limit >= 1)
178 sch->flags |= TCQ_F_CAN_BYPASS;
179 else
180 sch->flags &= ~TCQ_F_CAN_BYPASS;
181
182 return 0;
183}
184
185static int codel_dump(struct Qdisc *sch, struct sk_buff *skb)
186{
187 struct codel_sched_data *q = qdisc_priv(sch);
188 struct nlattr *opts;
189
190 opts = nla_nest_start(skb, TCA_OPTIONS);
191 if (opts == NULL)
192 goto nla_put_failure;
193
194 if (nla_put_u32(skb, TCA_CODEL_TARGET,
195 codel_time_to_us(q->params.target)) ||
196 nla_put_u32(skb, TCA_CODEL_LIMIT,
197 sch->limit) ||
198 nla_put_u32(skb, TCA_CODEL_INTERVAL,
199 codel_time_to_us(q->params.interval)) ||
200 nla_put_u32(skb, TCA_CODEL_ECN,
201 q->params.ecn))
202 goto nla_put_failure;
203
204 return nla_nest_end(skb, opts);
205
206nla_put_failure:
207 nla_nest_cancel(skb, opts);
208 return -1;
209}
210
211static int codel_dump_stats(struct Qdisc *sch, struct gnet_dump *d)
212{
213 const struct codel_sched_data *q = qdisc_priv(sch);
214 struct tc_codel_xstats st = {
215 .maxpacket = q->stats.maxpacket,
216 .count = q->vars.count,
217 .lastcount = q->vars.lastcount,
218 .drop_overlimit = q->drop_overlimit,
219 .ldelay = codel_time_to_us(q->vars.ldelay),
220 .dropping = q->vars.dropping,
221 .ecn_mark = q->stats.ecn_mark,
222 };
223
224 if (q->vars.dropping) {
225 codel_tdiff_t delta = q->vars.drop_next - codel_get_time();
226
227 if (delta >= 0)
228 st.drop_next = codel_time_to_us(delta);
229 else
230 st.drop_next = -codel_time_to_us(-delta);
231 }
232
233 return gnet_stats_copy_app(d, &st, sizeof(st));
234}
235
236static void codel_reset(struct Qdisc *sch)
237{
238 struct codel_sched_data *q = qdisc_priv(sch);
239
240 qdisc_reset_queue(sch);
241 codel_vars_init(&q->vars);
242}
243
244static struct Qdisc_ops codel_qdisc_ops __read_mostly = {
245 .id = "codel",
246 .priv_size = sizeof(struct codel_sched_data),
247
248 .enqueue = codel_qdisc_enqueue,
249 .dequeue = codel_qdisc_dequeue,
250 .peek = qdisc_peek_dequeued,
251 .init = codel_init,
252 .reset = codel_reset,
253 .change = codel_change,
254 .dump = codel_dump,
255 .dump_stats = codel_dump_stats,
256 .owner = THIS_MODULE,
257};
258
259static int __init codel_module_init(void)
260{
261 return register_qdisc(&codel_qdisc_ops);
262}
263
264static void __exit codel_module_exit(void)
265{
266 unregister_qdisc(&codel_qdisc_ops);
267}
268
269module_init(codel_module_init)
270module_exit(codel_module_exit)
271
272MODULE_DESCRIPTION("Controlled Delay queue discipline");
273MODULE_AUTHOR("Dave Taht");
274MODULE_AUTHOR("Eric Dumazet");
275MODULE_LICENSE("Dual BSD/GPL");
generated by cgit v1.2.2 (git 2.25.0) at 2025-01-17 22:20:23 -0500