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4b549a2e ED |
1 | /* |
2 | * Fair Queue CoDel discipline | |
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 | * Copyright (C) 2012 Eric Dumazet <edumazet@google.com> | |
10 | */ | |
11 | ||
12 | #include <linux/module.h> | |
13 | #include <linux/types.h> | |
14 | #include <linux/kernel.h> | |
15 | #include <linux/jiffies.h> | |
16 | #include <linux/string.h> | |
17 | #include <linux/in.h> | |
18 | #include <linux/errno.h> | |
19 | #include <linux/init.h> | |
20 | #include <linux/skbuff.h> | |
21 | #include <linux/jhash.h> | |
22 | #include <linux/slab.h> | |
23 | #include <linux/vmalloc.h> | |
24 | #include <net/netlink.h> | |
25 | #include <net/pkt_sched.h> | |
26 | #include <net/flow_keys.h> | |
27 | #include <net/codel.h> | |
28 | ||
29 | /* Fair Queue CoDel. | |
30 | * | |
31 | * Principles : | |
32 | * Packets are classified (internal classifier or external) on flows. | |
33 | * This is a Stochastic model (as we use a hash, several flows | |
34 | * might be hashed on same slot) | |
35 | * Each flow has a CoDel managed queue. | |
36 | * Flows are linked onto two (Round Robin) lists, | |
37 | * so that new flows have priority on old ones. | |
38 | * | |
39 | * For a given flow, packets are not reordered (CoDel uses a FIFO) | |
40 | * head drops only. | |
41 | * ECN capability is on by default. | |
42 | * Low memory footprint (64 bytes per flow) | |
43 | */ | |
44 | ||
45 | struct fq_codel_flow { | |
46 | struct sk_buff *head; | |
47 | struct sk_buff *tail; | |
48 | struct list_head flowchain; | |
49 | int deficit; | |
50 | u32 dropped; /* number of drops (or ECN marks) on this flow */ | |
51 | struct codel_vars cvars; | |
52 | }; /* please try to keep this structure <= 64 bytes */ | |
53 | ||
54 | struct fq_codel_sched_data { | |
55 | struct tcf_proto *filter_list; /* optional external classifier */ | |
56 | struct fq_codel_flow *flows; /* Flows table [flows_cnt] */ | |
57 | u32 *backlogs; /* backlog table [flows_cnt] */ | |
58 | u32 flows_cnt; /* number of flows */ | |
59 | u32 perturbation; /* hash perturbation */ | |
60 | u32 quantum; /* psched_mtu(qdisc_dev(sch)); */ | |
61 | struct codel_params cparams; | |
62 | struct codel_stats cstats; | |
63 | u32 drop_overlimit; | |
64 | u32 new_flow_count; | |
65 | ||
66 | struct list_head new_flows; /* list of new flows */ | |
67 | struct list_head old_flows; /* list of old flows */ | |
68 | }; | |
69 | ||
70 | static unsigned int fq_codel_hash(const struct fq_codel_sched_data *q, | |
71 | const struct sk_buff *skb) | |
72 | { | |
73 | struct flow_keys keys; | |
74 | unsigned int hash; | |
75 | ||
76 | skb_flow_dissect(skb, &keys); | |
77 | hash = jhash_3words((__force u32)keys.dst, | |
78 | (__force u32)keys.src ^ keys.ip_proto, | |
79 | (__force u32)keys.ports, q->perturbation); | |
80 | return ((u64)hash * q->flows_cnt) >> 32; | |
81 | } | |
82 | ||
83 | static unsigned int fq_codel_classify(struct sk_buff *skb, struct Qdisc *sch, | |
84 | int *qerr) | |
85 | { | |
86 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
87 | struct tcf_result res; | |
88 | int result; | |
89 | ||
90 | if (TC_H_MAJ(skb->priority) == sch->handle && | |
91 | TC_H_MIN(skb->priority) > 0 && | |
92 | TC_H_MIN(skb->priority) <= q->flows_cnt) | |
93 | return TC_H_MIN(skb->priority); | |
94 | ||
95 | if (!q->filter_list) | |
96 | return fq_codel_hash(q, skb) + 1; | |
97 | ||
98 | *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS; | |
99 | result = tc_classify(skb, q->filter_list, &res); | |
100 | if (result >= 0) { | |
101 | #ifdef CONFIG_NET_CLS_ACT | |
102 | switch (result) { | |
103 | case TC_ACT_STOLEN: | |
104 | case TC_ACT_QUEUED: | |
105 | *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN; | |
106 | case TC_ACT_SHOT: | |
107 | return 0; | |
108 | } | |
109 | #endif | |
110 | if (TC_H_MIN(res.classid) <= q->flows_cnt) | |
111 | return TC_H_MIN(res.classid); | |
112 | } | |
113 | return 0; | |
114 | } | |
115 | ||
116 | /* helper functions : might be changed when/if skb use a standard list_head */ | |
117 | ||
118 | /* remove one skb from head of slot queue */ | |
119 | static inline struct sk_buff *dequeue_head(struct fq_codel_flow *flow) | |
120 | { | |
121 | struct sk_buff *skb = flow->head; | |
122 | ||
123 | flow->head = skb->next; | |
124 | skb->next = NULL; | |
125 | return skb; | |
126 | } | |
127 | ||
128 | /* add skb to flow queue (tail add) */ | |
129 | static inline void flow_queue_add(struct fq_codel_flow *flow, | |
130 | struct sk_buff *skb) | |
131 | { | |
132 | if (flow->head == NULL) | |
133 | flow->head = skb; | |
134 | else | |
135 | flow->tail->next = skb; | |
136 | flow->tail = skb; | |
137 | skb->next = NULL; | |
138 | } | |
139 | ||
140 | static unsigned int fq_codel_drop(struct Qdisc *sch) | |
141 | { | |
142 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
143 | struct sk_buff *skb; | |
144 | unsigned int maxbacklog = 0, idx = 0, i, len; | |
145 | struct fq_codel_flow *flow; | |
146 | ||
147 | /* Queue is full! Find the fat flow and drop packet from it. | |
148 | * This might sound expensive, but with 1024 flows, we scan | |
149 | * 4KB of memory, and we dont need to handle a complex tree | |
150 | * in fast path (packet queue/enqueue) with many cache misses. | |
151 | */ | |
152 | for (i = 0; i < q->flows_cnt; i++) { | |
153 | if (q->backlogs[i] > maxbacklog) { | |
154 | maxbacklog = q->backlogs[i]; | |
155 | idx = i; | |
156 | } | |
157 | } | |
158 | flow = &q->flows[idx]; | |
159 | skb = dequeue_head(flow); | |
160 | len = qdisc_pkt_len(skb); | |
161 | q->backlogs[idx] -= len; | |
162 | kfree_skb(skb); | |
163 | sch->q.qlen--; | |
164 | sch->qstats.drops++; | |
165 | sch->qstats.backlog -= len; | |
166 | flow->dropped++; | |
167 | return idx; | |
168 | } | |
169 | ||
170 | static int fq_codel_enqueue(struct sk_buff *skb, struct Qdisc *sch) | |
171 | { | |
172 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
173 | unsigned int idx; | |
174 | struct fq_codel_flow *flow; | |
175 | int uninitialized_var(ret); | |
176 | ||
177 | idx = fq_codel_classify(skb, sch, &ret); | |
178 | if (idx == 0) { | |
179 | if (ret & __NET_XMIT_BYPASS) | |
180 | sch->qstats.drops++; | |
181 | kfree_skb(skb); | |
182 | return ret; | |
183 | } | |
184 | idx--; | |
185 | ||
186 | codel_set_enqueue_time(skb); | |
187 | flow = &q->flows[idx]; | |
188 | flow_queue_add(flow, skb); | |
189 | q->backlogs[idx] += qdisc_pkt_len(skb); | |
190 | sch->qstats.backlog += qdisc_pkt_len(skb); | |
191 | ||
192 | if (list_empty(&flow->flowchain)) { | |
193 | list_add_tail(&flow->flowchain, &q->new_flows); | |
4b549a2e ED |
194 | q->new_flow_count++; |
195 | flow->deficit = q->quantum; | |
196 | flow->dropped = 0; | |
197 | } | |
cd68ddd4 | 198 | if (++sch->q.qlen <= sch->limit) |
4b549a2e ED |
199 | return NET_XMIT_SUCCESS; |
200 | ||
201 | q->drop_overlimit++; | |
202 | /* Return Congestion Notification only if we dropped a packet | |
203 | * from this flow. | |
204 | */ | |
205 | if (fq_codel_drop(sch) == idx) | |
206 | return NET_XMIT_CN; | |
207 | ||
208 | /* As we dropped a packet, better let upper stack know this */ | |
209 | qdisc_tree_decrease_qlen(sch, 1); | |
210 | return NET_XMIT_SUCCESS; | |
211 | } | |
212 | ||
213 | /* This is the specific function called from codel_dequeue() | |
214 | * to dequeue a packet from queue. Note: backlog is handled in | |
215 | * codel, we dont need to reduce it here. | |
216 | */ | |
217 | static struct sk_buff *dequeue(struct codel_vars *vars, struct Qdisc *sch) | |
218 | { | |
865ec552 | 219 | struct fq_codel_sched_data *q = qdisc_priv(sch); |
4b549a2e ED |
220 | struct fq_codel_flow *flow; |
221 | struct sk_buff *skb = NULL; | |
222 | ||
223 | flow = container_of(vars, struct fq_codel_flow, cvars); | |
224 | if (flow->head) { | |
225 | skb = dequeue_head(flow); | |
865ec552 | 226 | q->backlogs[flow - q->flows] -= qdisc_pkt_len(skb); |
4b549a2e ED |
227 | sch->q.qlen--; |
228 | } | |
229 | return skb; | |
230 | } | |
231 | ||
232 | static struct sk_buff *fq_codel_dequeue(struct Qdisc *sch) | |
233 | { | |
234 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
235 | struct sk_buff *skb; | |
236 | struct fq_codel_flow *flow; | |
237 | struct list_head *head; | |
238 | u32 prev_drop_count, prev_ecn_mark; | |
239 | ||
240 | begin: | |
241 | head = &q->new_flows; | |
242 | if (list_empty(head)) { | |
243 | head = &q->old_flows; | |
244 | if (list_empty(head)) | |
245 | return NULL; | |
246 | } | |
247 | flow = list_first_entry(head, struct fq_codel_flow, flowchain); | |
248 | ||
249 | if (flow->deficit <= 0) { | |
250 | flow->deficit += q->quantum; | |
251 | list_move_tail(&flow->flowchain, &q->old_flows); | |
252 | goto begin; | |
253 | } | |
254 | ||
255 | prev_drop_count = q->cstats.drop_count; | |
256 | prev_ecn_mark = q->cstats.ecn_mark; | |
257 | ||
258 | skb = codel_dequeue(sch, &q->cparams, &flow->cvars, &q->cstats, | |
865ec552 | 259 | dequeue); |
4b549a2e ED |
260 | |
261 | flow->dropped += q->cstats.drop_count - prev_drop_count; | |
262 | flow->dropped += q->cstats.ecn_mark - prev_ecn_mark; | |
263 | ||
264 | if (!skb) { | |
265 | /* force a pass through old_flows to prevent starvation */ | |
266 | if ((head == &q->new_flows) && !list_empty(&q->old_flows)) | |
267 | list_move_tail(&flow->flowchain, &q->old_flows); | |
268 | else | |
269 | list_del_init(&flow->flowchain); | |
270 | goto begin; | |
271 | } | |
272 | qdisc_bstats_update(sch, skb); | |
273 | flow->deficit -= qdisc_pkt_len(skb); | |
274 | /* We cant call qdisc_tree_decrease_qlen() if our qlen is 0, | |
275 | * or HTB crashes. Defer it for next round. | |
276 | */ | |
277 | if (q->cstats.drop_count && sch->q.qlen) { | |
278 | qdisc_tree_decrease_qlen(sch, q->cstats.drop_count); | |
279 | q->cstats.drop_count = 0; | |
280 | } | |
281 | return skb; | |
282 | } | |
283 | ||
284 | static void fq_codel_reset(struct Qdisc *sch) | |
285 | { | |
286 | struct sk_buff *skb; | |
287 | ||
288 | while ((skb = fq_codel_dequeue(sch)) != NULL) | |
289 | kfree_skb(skb); | |
290 | } | |
291 | ||
292 | static const struct nla_policy fq_codel_policy[TCA_FQ_CODEL_MAX + 1] = { | |
293 | [TCA_FQ_CODEL_TARGET] = { .type = NLA_U32 }, | |
294 | [TCA_FQ_CODEL_LIMIT] = { .type = NLA_U32 }, | |
295 | [TCA_FQ_CODEL_INTERVAL] = { .type = NLA_U32 }, | |
296 | [TCA_FQ_CODEL_ECN] = { .type = NLA_U32 }, | |
297 | [TCA_FQ_CODEL_FLOWS] = { .type = NLA_U32 }, | |
298 | [TCA_FQ_CODEL_QUANTUM] = { .type = NLA_U32 }, | |
299 | }; | |
300 | ||
301 | static int fq_codel_change(struct Qdisc *sch, struct nlattr *opt) | |
302 | { | |
303 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
304 | struct nlattr *tb[TCA_FQ_CODEL_MAX + 1]; | |
305 | int err; | |
306 | ||
307 | if (!opt) | |
308 | return -EINVAL; | |
309 | ||
310 | err = nla_parse_nested(tb, TCA_FQ_CODEL_MAX, opt, fq_codel_policy); | |
311 | if (err < 0) | |
312 | return err; | |
313 | if (tb[TCA_FQ_CODEL_FLOWS]) { | |
314 | if (q->flows) | |
315 | return -EINVAL; | |
316 | q->flows_cnt = nla_get_u32(tb[TCA_FQ_CODEL_FLOWS]); | |
317 | if (!q->flows_cnt || | |
318 | q->flows_cnt > 65536) | |
319 | return -EINVAL; | |
320 | } | |
321 | sch_tree_lock(sch); | |
322 | ||
323 | if (tb[TCA_FQ_CODEL_TARGET]) { | |
324 | u64 target = nla_get_u32(tb[TCA_FQ_CODEL_TARGET]); | |
325 | ||
326 | q->cparams.target = (target * NSEC_PER_USEC) >> CODEL_SHIFT; | |
327 | } | |
328 | ||
329 | if (tb[TCA_FQ_CODEL_INTERVAL]) { | |
330 | u64 interval = nla_get_u32(tb[TCA_FQ_CODEL_INTERVAL]); | |
331 | ||
332 | q->cparams.interval = (interval * NSEC_PER_USEC) >> CODEL_SHIFT; | |
333 | } | |
334 | ||
335 | if (tb[TCA_FQ_CODEL_LIMIT]) | |
336 | sch->limit = nla_get_u32(tb[TCA_FQ_CODEL_LIMIT]); | |
337 | ||
338 | if (tb[TCA_FQ_CODEL_ECN]) | |
339 | q->cparams.ecn = !!nla_get_u32(tb[TCA_FQ_CODEL_ECN]); | |
340 | ||
341 | if (tb[TCA_FQ_CODEL_QUANTUM]) | |
342 | q->quantum = max(256U, nla_get_u32(tb[TCA_FQ_CODEL_QUANTUM])); | |
343 | ||
344 | while (sch->q.qlen > sch->limit) { | |
345 | struct sk_buff *skb = fq_codel_dequeue(sch); | |
346 | ||
347 | kfree_skb(skb); | |
348 | q->cstats.drop_count++; | |
349 | } | |
350 | qdisc_tree_decrease_qlen(sch, q->cstats.drop_count); | |
351 | q->cstats.drop_count = 0; | |
352 | ||
353 | sch_tree_unlock(sch); | |
354 | return 0; | |
355 | } | |
356 | ||
357 | static void *fq_codel_zalloc(size_t sz) | |
358 | { | |
359 | void *ptr = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN); | |
360 | ||
361 | if (!ptr) | |
362 | ptr = vzalloc(sz); | |
363 | return ptr; | |
364 | } | |
365 | ||
366 | static void fq_codel_free(void *addr) | |
367 | { | |
368 | if (addr) { | |
369 | if (is_vmalloc_addr(addr)) | |
370 | vfree(addr); | |
371 | else | |
372 | kfree(addr); | |
373 | } | |
374 | } | |
375 | ||
376 | static void fq_codel_destroy(struct Qdisc *sch) | |
377 | { | |
378 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
379 | ||
380 | tcf_destroy_chain(&q->filter_list); | |
381 | fq_codel_free(q->backlogs); | |
382 | fq_codel_free(q->flows); | |
383 | } | |
384 | ||
385 | static int fq_codel_init(struct Qdisc *sch, struct nlattr *opt) | |
386 | { | |
387 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
388 | int i; | |
389 | ||
390 | sch->limit = 10*1024; | |
391 | q->flows_cnt = 1024; | |
392 | q->quantum = psched_mtu(qdisc_dev(sch)); | |
393 | q->perturbation = net_random(); | |
394 | INIT_LIST_HEAD(&q->new_flows); | |
395 | INIT_LIST_HEAD(&q->old_flows); | |
396 | codel_params_init(&q->cparams); | |
397 | codel_stats_init(&q->cstats); | |
398 | q->cparams.ecn = true; | |
399 | ||
400 | if (opt) { | |
401 | int err = fq_codel_change(sch, opt); | |
402 | if (err) | |
403 | return err; | |
404 | } | |
405 | ||
406 | if (!q->flows) { | |
407 | q->flows = fq_codel_zalloc(q->flows_cnt * | |
408 | sizeof(struct fq_codel_flow)); | |
409 | if (!q->flows) | |
410 | return -ENOMEM; | |
411 | q->backlogs = fq_codel_zalloc(q->flows_cnt * sizeof(u32)); | |
412 | if (!q->backlogs) { | |
413 | fq_codel_free(q->flows); | |
414 | return -ENOMEM; | |
415 | } | |
416 | for (i = 0; i < q->flows_cnt; i++) { | |
417 | struct fq_codel_flow *flow = q->flows + i; | |
418 | ||
419 | INIT_LIST_HEAD(&flow->flowchain); | |
b379135c | 420 | codel_vars_init(&flow->cvars); |
4b549a2e ED |
421 | } |
422 | } | |
423 | if (sch->limit >= 1) | |
424 | sch->flags |= TCQ_F_CAN_BYPASS; | |
425 | else | |
426 | sch->flags &= ~TCQ_F_CAN_BYPASS; | |
427 | return 0; | |
428 | } | |
429 | ||
430 | static int fq_codel_dump(struct Qdisc *sch, struct sk_buff *skb) | |
431 | { | |
432 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
433 | struct nlattr *opts; | |
434 | ||
435 | opts = nla_nest_start(skb, TCA_OPTIONS); | |
436 | if (opts == NULL) | |
437 | goto nla_put_failure; | |
438 | ||
439 | if (nla_put_u32(skb, TCA_FQ_CODEL_TARGET, | |
440 | codel_time_to_us(q->cparams.target)) || | |
441 | nla_put_u32(skb, TCA_FQ_CODEL_LIMIT, | |
442 | sch->limit) || | |
443 | nla_put_u32(skb, TCA_FQ_CODEL_INTERVAL, | |
444 | codel_time_to_us(q->cparams.interval)) || | |
445 | nla_put_u32(skb, TCA_FQ_CODEL_ECN, | |
446 | q->cparams.ecn) || | |
447 | nla_put_u32(skb, TCA_FQ_CODEL_QUANTUM, | |
448 | q->quantum) || | |
449 | nla_put_u32(skb, TCA_FQ_CODEL_FLOWS, | |
450 | q->flows_cnt)) | |
451 | goto nla_put_failure; | |
452 | ||
453 | nla_nest_end(skb, opts); | |
454 | return skb->len; | |
455 | ||
456 | nla_put_failure: | |
457 | return -1; | |
458 | } | |
459 | ||
460 | static int fq_codel_dump_stats(struct Qdisc *sch, struct gnet_dump *d) | |
461 | { | |
462 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
463 | struct tc_fq_codel_xstats st = { | |
464 | .type = TCA_FQ_CODEL_XSTATS_QDISC, | |
4b549a2e ED |
465 | }; |
466 | struct list_head *pos; | |
467 | ||
669d67bf SL |
468 | st.qdisc_stats.maxpacket = q->cstats.maxpacket; |
469 | st.qdisc_stats.drop_overlimit = q->drop_overlimit; | |
470 | st.qdisc_stats.ecn_mark = q->cstats.ecn_mark; | |
471 | st.qdisc_stats.new_flow_count = q->new_flow_count; | |
472 | ||
4b549a2e ED |
473 | list_for_each(pos, &q->new_flows) |
474 | st.qdisc_stats.new_flows_len++; | |
475 | ||
476 | list_for_each(pos, &q->old_flows) | |
477 | st.qdisc_stats.old_flows_len++; | |
478 | ||
479 | return gnet_stats_copy_app(d, &st, sizeof(st)); | |
480 | } | |
481 | ||
482 | static struct Qdisc *fq_codel_leaf(struct Qdisc *sch, unsigned long arg) | |
483 | { | |
484 | return NULL; | |
485 | } | |
486 | ||
487 | static unsigned long fq_codel_get(struct Qdisc *sch, u32 classid) | |
488 | { | |
489 | return 0; | |
490 | } | |
491 | ||
492 | static unsigned long fq_codel_bind(struct Qdisc *sch, unsigned long parent, | |
493 | u32 classid) | |
494 | { | |
495 | /* we cannot bypass queue discipline anymore */ | |
496 | sch->flags &= ~TCQ_F_CAN_BYPASS; | |
497 | return 0; | |
498 | } | |
499 | ||
500 | static void fq_codel_put(struct Qdisc *q, unsigned long cl) | |
501 | { | |
502 | } | |
503 | ||
504 | static struct tcf_proto **fq_codel_find_tcf(struct Qdisc *sch, unsigned long cl) | |
505 | { | |
506 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
507 | ||
508 | if (cl) | |
509 | return NULL; | |
510 | return &q->filter_list; | |
511 | } | |
512 | ||
513 | static int fq_codel_dump_class(struct Qdisc *sch, unsigned long cl, | |
514 | struct sk_buff *skb, struct tcmsg *tcm) | |
515 | { | |
516 | tcm->tcm_handle |= TC_H_MIN(cl); | |
517 | return 0; | |
518 | } | |
519 | ||
520 | static int fq_codel_dump_class_stats(struct Qdisc *sch, unsigned long cl, | |
521 | struct gnet_dump *d) | |
522 | { | |
523 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
524 | u32 idx = cl - 1; | |
525 | struct gnet_stats_queue qs = { 0 }; | |
526 | struct tc_fq_codel_xstats xstats; | |
527 | ||
528 | if (idx < q->flows_cnt) { | |
529 | const struct fq_codel_flow *flow = &q->flows[idx]; | |
530 | const struct sk_buff *skb = flow->head; | |
531 | ||
532 | memset(&xstats, 0, sizeof(xstats)); | |
533 | xstats.type = TCA_FQ_CODEL_XSTATS_CLASS; | |
534 | xstats.class_stats.deficit = flow->deficit; | |
535 | xstats.class_stats.ldelay = | |
536 | codel_time_to_us(flow->cvars.ldelay); | |
537 | xstats.class_stats.count = flow->cvars.count; | |
538 | xstats.class_stats.lastcount = flow->cvars.lastcount; | |
539 | xstats.class_stats.dropping = flow->cvars.dropping; | |
540 | if (flow->cvars.dropping) { | |
541 | codel_tdiff_t delta = flow->cvars.drop_next - | |
542 | codel_get_time(); | |
543 | ||
544 | xstats.class_stats.drop_next = (delta >= 0) ? | |
545 | codel_time_to_us(delta) : | |
546 | -codel_time_to_us(-delta); | |
547 | } | |
548 | while (skb) { | |
549 | qs.qlen++; | |
550 | skb = skb->next; | |
551 | } | |
552 | qs.backlog = q->backlogs[idx]; | |
553 | qs.drops = flow->dropped; | |
554 | } | |
555 | if (gnet_stats_copy_queue(d, &qs) < 0) | |
556 | return -1; | |
557 | if (idx < q->flows_cnt) | |
558 | return gnet_stats_copy_app(d, &xstats, sizeof(xstats)); | |
559 | return 0; | |
560 | } | |
561 | ||
562 | static void fq_codel_walk(struct Qdisc *sch, struct qdisc_walker *arg) | |
563 | { | |
564 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
565 | unsigned int i; | |
566 | ||
567 | if (arg->stop) | |
568 | return; | |
569 | ||
570 | for (i = 0; i < q->flows_cnt; i++) { | |
571 | if (list_empty(&q->flows[i].flowchain) || | |
572 | arg->count < arg->skip) { | |
573 | arg->count++; | |
574 | continue; | |
575 | } | |
576 | if (arg->fn(sch, i + 1, arg) < 0) { | |
577 | arg->stop = 1; | |
578 | break; | |
579 | } | |
580 | arg->count++; | |
581 | } | |
582 | } | |
583 | ||
584 | static const struct Qdisc_class_ops fq_codel_class_ops = { | |
585 | .leaf = fq_codel_leaf, | |
586 | .get = fq_codel_get, | |
587 | .put = fq_codel_put, | |
588 | .tcf_chain = fq_codel_find_tcf, | |
589 | .bind_tcf = fq_codel_bind, | |
590 | .unbind_tcf = fq_codel_put, | |
591 | .dump = fq_codel_dump_class, | |
592 | .dump_stats = fq_codel_dump_class_stats, | |
593 | .walk = fq_codel_walk, | |
594 | }; | |
595 | ||
596 | static struct Qdisc_ops fq_codel_qdisc_ops __read_mostly = { | |
597 | .cl_ops = &fq_codel_class_ops, | |
598 | .id = "fq_codel", | |
599 | .priv_size = sizeof(struct fq_codel_sched_data), | |
600 | .enqueue = fq_codel_enqueue, | |
601 | .dequeue = fq_codel_dequeue, | |
602 | .peek = qdisc_peek_dequeued, | |
603 | .drop = fq_codel_drop, | |
604 | .init = fq_codel_init, | |
605 | .reset = fq_codel_reset, | |
606 | .destroy = fq_codel_destroy, | |
607 | .change = fq_codel_change, | |
608 | .dump = fq_codel_dump, | |
609 | .dump_stats = fq_codel_dump_stats, | |
610 | .owner = THIS_MODULE, | |
611 | }; | |
612 | ||
613 | static int __init fq_codel_module_init(void) | |
614 | { | |
615 | return register_qdisc(&fq_codel_qdisc_ops); | |
616 | } | |
617 | ||
618 | static void __exit fq_codel_module_exit(void) | |
619 | { | |
620 | unregister_qdisc(&fq_codel_qdisc_ops); | |
621 | } | |
622 | ||
623 | module_init(fq_codel_module_init) | |
624 | module_exit(fq_codel_module_exit) | |
625 | MODULE_AUTHOR("Eric Dumazet"); | |
626 | MODULE_LICENSE("GPL"); |