]>
Commit | Line | Data |
---|---|---|
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); | |
8fc54f68 DB |
80 | |
81 | return reciprocal_scale(hash, q->flows_cnt); | |
4b549a2e ED |
82 | } |
83 | ||
84 | static unsigned int fq_codel_classify(struct sk_buff *skb, struct Qdisc *sch, | |
85 | int *qerr) | |
86 | { | |
87 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
88 | struct tcf_result res; | |
89 | int result; | |
90 | ||
91 | if (TC_H_MAJ(skb->priority) == sch->handle && | |
92 | TC_H_MIN(skb->priority) > 0 && | |
93 | TC_H_MIN(skb->priority) <= q->flows_cnt) | |
94 | return TC_H_MIN(skb->priority); | |
95 | ||
96 | if (!q->filter_list) | |
97 | return fq_codel_hash(q, skb) + 1; | |
98 | ||
99 | *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS; | |
100 | result = tc_classify(skb, q->filter_list, &res); | |
101 | if (result >= 0) { | |
102 | #ifdef CONFIG_NET_CLS_ACT | |
103 | switch (result) { | |
104 | case TC_ACT_STOLEN: | |
105 | case TC_ACT_QUEUED: | |
106 | *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN; | |
107 | case TC_ACT_SHOT: | |
108 | return 0; | |
109 | } | |
110 | #endif | |
111 | if (TC_H_MIN(res.classid) <= q->flows_cnt) | |
112 | return TC_H_MIN(res.classid); | |
113 | } | |
114 | return 0; | |
115 | } | |
116 | ||
117 | /* helper functions : might be changed when/if skb use a standard list_head */ | |
118 | ||
119 | /* remove one skb from head of slot queue */ | |
120 | static inline struct sk_buff *dequeue_head(struct fq_codel_flow *flow) | |
121 | { | |
122 | struct sk_buff *skb = flow->head; | |
123 | ||
124 | flow->head = skb->next; | |
125 | skb->next = NULL; | |
126 | return skb; | |
127 | } | |
128 | ||
129 | /* add skb to flow queue (tail add) */ | |
130 | static inline void flow_queue_add(struct fq_codel_flow *flow, | |
131 | struct sk_buff *skb) | |
132 | { | |
133 | if (flow->head == NULL) | |
134 | flow->head = skb; | |
135 | else | |
136 | flow->tail->next = skb; | |
137 | flow->tail = skb; | |
138 | skb->next = NULL; | |
139 | } | |
140 | ||
141 | static unsigned int fq_codel_drop(struct Qdisc *sch) | |
142 | { | |
143 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
144 | struct sk_buff *skb; | |
145 | unsigned int maxbacklog = 0, idx = 0, i, len; | |
146 | struct fq_codel_flow *flow; | |
147 | ||
148 | /* Queue is full! Find the fat flow and drop packet from it. | |
149 | * This might sound expensive, but with 1024 flows, we scan | |
150 | * 4KB of memory, and we dont need to handle a complex tree | |
151 | * in fast path (packet queue/enqueue) with many cache misses. | |
152 | */ | |
153 | for (i = 0; i < q->flows_cnt; i++) { | |
154 | if (q->backlogs[i] > maxbacklog) { | |
155 | maxbacklog = q->backlogs[i]; | |
156 | idx = i; | |
157 | } | |
158 | } | |
159 | flow = &q->flows[idx]; | |
160 | skb = dequeue_head(flow); | |
161 | len = qdisc_pkt_len(skb); | |
162 | q->backlogs[idx] -= len; | |
163 | kfree_skb(skb); | |
164 | sch->q.qlen--; | |
165 | sch->qstats.drops++; | |
166 | sch->qstats.backlog -= len; | |
167 | flow->dropped++; | |
168 | return idx; | |
169 | } | |
170 | ||
171 | static int fq_codel_enqueue(struct sk_buff *skb, struct Qdisc *sch) | |
172 | { | |
173 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
174 | unsigned int idx; | |
175 | struct fq_codel_flow *flow; | |
176 | int uninitialized_var(ret); | |
177 | ||
178 | idx = fq_codel_classify(skb, sch, &ret); | |
179 | if (idx == 0) { | |
180 | if (ret & __NET_XMIT_BYPASS) | |
181 | sch->qstats.drops++; | |
182 | kfree_skb(skb); | |
183 | return ret; | |
184 | } | |
185 | idx--; | |
186 | ||
187 | codel_set_enqueue_time(skb); | |
188 | flow = &q->flows[idx]; | |
189 | flow_queue_add(flow, skb); | |
190 | q->backlogs[idx] += qdisc_pkt_len(skb); | |
191 | sch->qstats.backlog += qdisc_pkt_len(skb); | |
192 | ||
193 | if (list_empty(&flow->flowchain)) { | |
194 | list_add_tail(&flow->flowchain, &q->new_flows); | |
4b549a2e ED |
195 | q->new_flow_count++; |
196 | flow->deficit = q->quantum; | |
197 | flow->dropped = 0; | |
198 | } | |
cd68ddd4 | 199 | if (++sch->q.qlen <= sch->limit) |
4b549a2e ED |
200 | return NET_XMIT_SUCCESS; |
201 | ||
202 | q->drop_overlimit++; | |
203 | /* Return Congestion Notification only if we dropped a packet | |
204 | * from this flow. | |
205 | */ | |
206 | if (fq_codel_drop(sch) == idx) | |
207 | return NET_XMIT_CN; | |
208 | ||
209 | /* As we dropped a packet, better let upper stack know this */ | |
210 | qdisc_tree_decrease_qlen(sch, 1); | |
211 | return NET_XMIT_SUCCESS; | |
212 | } | |
213 | ||
214 | /* This is the specific function called from codel_dequeue() | |
215 | * to dequeue a packet from queue. Note: backlog is handled in | |
216 | * codel, we dont need to reduce it here. | |
217 | */ | |
218 | static struct sk_buff *dequeue(struct codel_vars *vars, struct Qdisc *sch) | |
219 | { | |
865ec552 | 220 | struct fq_codel_sched_data *q = qdisc_priv(sch); |
4b549a2e ED |
221 | struct fq_codel_flow *flow; |
222 | struct sk_buff *skb = NULL; | |
223 | ||
224 | flow = container_of(vars, struct fq_codel_flow, cvars); | |
225 | if (flow->head) { | |
226 | skb = dequeue_head(flow); | |
865ec552 | 227 | q->backlogs[flow - q->flows] -= qdisc_pkt_len(skb); |
4b549a2e ED |
228 | sch->q.qlen--; |
229 | } | |
230 | return skb; | |
231 | } | |
232 | ||
233 | static struct sk_buff *fq_codel_dequeue(struct Qdisc *sch) | |
234 | { | |
235 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
236 | struct sk_buff *skb; | |
237 | struct fq_codel_flow *flow; | |
238 | struct list_head *head; | |
239 | u32 prev_drop_count, prev_ecn_mark; | |
240 | ||
241 | begin: | |
242 | head = &q->new_flows; | |
243 | if (list_empty(head)) { | |
244 | head = &q->old_flows; | |
245 | if (list_empty(head)) | |
246 | return NULL; | |
247 | } | |
248 | flow = list_first_entry(head, struct fq_codel_flow, flowchain); | |
249 | ||
250 | if (flow->deficit <= 0) { | |
251 | flow->deficit += q->quantum; | |
252 | list_move_tail(&flow->flowchain, &q->old_flows); | |
253 | goto begin; | |
254 | } | |
255 | ||
256 | prev_drop_count = q->cstats.drop_count; | |
257 | prev_ecn_mark = q->cstats.ecn_mark; | |
258 | ||
259 | skb = codel_dequeue(sch, &q->cparams, &flow->cvars, &q->cstats, | |
865ec552 | 260 | dequeue); |
4b549a2e ED |
261 | |
262 | flow->dropped += q->cstats.drop_count - prev_drop_count; | |
263 | flow->dropped += q->cstats.ecn_mark - prev_ecn_mark; | |
264 | ||
265 | if (!skb) { | |
266 | /* force a pass through old_flows to prevent starvation */ | |
267 | if ((head == &q->new_flows) && !list_empty(&q->old_flows)) | |
268 | list_move_tail(&flow->flowchain, &q->old_flows); | |
269 | else | |
270 | list_del_init(&flow->flowchain); | |
271 | goto begin; | |
272 | } | |
273 | qdisc_bstats_update(sch, skb); | |
274 | flow->deficit -= qdisc_pkt_len(skb); | |
275 | /* We cant call qdisc_tree_decrease_qlen() if our qlen is 0, | |
276 | * or HTB crashes. Defer it for next round. | |
277 | */ | |
278 | if (q->cstats.drop_count && sch->q.qlen) { | |
279 | qdisc_tree_decrease_qlen(sch, q->cstats.drop_count); | |
280 | q->cstats.drop_count = 0; | |
281 | } | |
282 | return skb; | |
283 | } | |
284 | ||
285 | static void fq_codel_reset(struct Qdisc *sch) | |
286 | { | |
287 | struct sk_buff *skb; | |
288 | ||
289 | while ((skb = fq_codel_dequeue(sch)) != NULL) | |
290 | kfree_skb(skb); | |
291 | } | |
292 | ||
293 | static const struct nla_policy fq_codel_policy[TCA_FQ_CODEL_MAX + 1] = { | |
294 | [TCA_FQ_CODEL_TARGET] = { .type = NLA_U32 }, | |
295 | [TCA_FQ_CODEL_LIMIT] = { .type = NLA_U32 }, | |
296 | [TCA_FQ_CODEL_INTERVAL] = { .type = NLA_U32 }, | |
297 | [TCA_FQ_CODEL_ECN] = { .type = NLA_U32 }, | |
298 | [TCA_FQ_CODEL_FLOWS] = { .type = NLA_U32 }, | |
299 | [TCA_FQ_CODEL_QUANTUM] = { .type = NLA_U32 }, | |
300 | }; | |
301 | ||
302 | static int fq_codel_change(struct Qdisc *sch, struct nlattr *opt) | |
303 | { | |
304 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
305 | struct nlattr *tb[TCA_FQ_CODEL_MAX + 1]; | |
306 | int err; | |
307 | ||
308 | if (!opt) | |
309 | return -EINVAL; | |
310 | ||
311 | err = nla_parse_nested(tb, TCA_FQ_CODEL_MAX, opt, fq_codel_policy); | |
312 | if (err < 0) | |
313 | return err; | |
314 | if (tb[TCA_FQ_CODEL_FLOWS]) { | |
315 | if (q->flows) | |
316 | return -EINVAL; | |
317 | q->flows_cnt = nla_get_u32(tb[TCA_FQ_CODEL_FLOWS]); | |
318 | if (!q->flows_cnt || | |
319 | q->flows_cnt > 65536) | |
320 | return -EINVAL; | |
321 | } | |
322 | sch_tree_lock(sch); | |
323 | ||
324 | if (tb[TCA_FQ_CODEL_TARGET]) { | |
325 | u64 target = nla_get_u32(tb[TCA_FQ_CODEL_TARGET]); | |
326 | ||
327 | q->cparams.target = (target * NSEC_PER_USEC) >> CODEL_SHIFT; | |
328 | } | |
329 | ||
330 | if (tb[TCA_FQ_CODEL_INTERVAL]) { | |
331 | u64 interval = nla_get_u32(tb[TCA_FQ_CODEL_INTERVAL]); | |
332 | ||
333 | q->cparams.interval = (interval * NSEC_PER_USEC) >> CODEL_SHIFT; | |
334 | } | |
335 | ||
336 | if (tb[TCA_FQ_CODEL_LIMIT]) | |
337 | sch->limit = nla_get_u32(tb[TCA_FQ_CODEL_LIMIT]); | |
338 | ||
339 | if (tb[TCA_FQ_CODEL_ECN]) | |
340 | q->cparams.ecn = !!nla_get_u32(tb[TCA_FQ_CODEL_ECN]); | |
341 | ||
342 | if (tb[TCA_FQ_CODEL_QUANTUM]) | |
343 | q->quantum = max(256U, nla_get_u32(tb[TCA_FQ_CODEL_QUANTUM])); | |
344 | ||
345 | while (sch->q.qlen > sch->limit) { | |
346 | struct sk_buff *skb = fq_codel_dequeue(sch); | |
347 | ||
348 | kfree_skb(skb); | |
349 | q->cstats.drop_count++; | |
350 | } | |
351 | qdisc_tree_decrease_qlen(sch, q->cstats.drop_count); | |
352 | q->cstats.drop_count = 0; | |
353 | ||
354 | sch_tree_unlock(sch); | |
355 | return 0; | |
356 | } | |
357 | ||
358 | static void *fq_codel_zalloc(size_t sz) | |
359 | { | |
360 | void *ptr = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN); | |
361 | ||
362 | if (!ptr) | |
363 | ptr = vzalloc(sz); | |
364 | return ptr; | |
365 | } | |
366 | ||
367 | static void fq_codel_free(void *addr) | |
368 | { | |
4cb28970 | 369 | kvfree(addr); |
4b549a2e ED |
370 | } |
371 | ||
372 | static void fq_codel_destroy(struct Qdisc *sch) | |
373 | { | |
374 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
375 | ||
376 | tcf_destroy_chain(&q->filter_list); | |
377 | fq_codel_free(q->backlogs); | |
378 | fq_codel_free(q->flows); | |
379 | } | |
380 | ||
381 | static int fq_codel_init(struct Qdisc *sch, struct nlattr *opt) | |
382 | { | |
383 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
384 | int i; | |
385 | ||
386 | sch->limit = 10*1024; | |
387 | q->flows_cnt = 1024; | |
388 | q->quantum = psched_mtu(qdisc_dev(sch)); | |
63862b5b | 389 | q->perturbation = prandom_u32(); |
4b549a2e ED |
390 | INIT_LIST_HEAD(&q->new_flows); |
391 | INIT_LIST_HEAD(&q->old_flows); | |
392 | codel_params_init(&q->cparams); | |
393 | codel_stats_init(&q->cstats); | |
394 | q->cparams.ecn = true; | |
395 | ||
396 | if (opt) { | |
397 | int err = fq_codel_change(sch, opt); | |
398 | if (err) | |
399 | return err; | |
400 | } | |
401 | ||
402 | if (!q->flows) { | |
403 | q->flows = fq_codel_zalloc(q->flows_cnt * | |
404 | sizeof(struct fq_codel_flow)); | |
405 | if (!q->flows) | |
406 | return -ENOMEM; | |
407 | q->backlogs = fq_codel_zalloc(q->flows_cnt * sizeof(u32)); | |
408 | if (!q->backlogs) { | |
409 | fq_codel_free(q->flows); | |
410 | return -ENOMEM; | |
411 | } | |
412 | for (i = 0; i < q->flows_cnt; i++) { | |
413 | struct fq_codel_flow *flow = q->flows + i; | |
414 | ||
415 | INIT_LIST_HEAD(&flow->flowchain); | |
b379135c | 416 | codel_vars_init(&flow->cvars); |
4b549a2e ED |
417 | } |
418 | } | |
419 | if (sch->limit >= 1) | |
420 | sch->flags |= TCQ_F_CAN_BYPASS; | |
421 | else | |
422 | sch->flags &= ~TCQ_F_CAN_BYPASS; | |
423 | return 0; | |
424 | } | |
425 | ||
426 | static int fq_codel_dump(struct Qdisc *sch, struct sk_buff *skb) | |
427 | { | |
428 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
429 | struct nlattr *opts; | |
430 | ||
431 | opts = nla_nest_start(skb, TCA_OPTIONS); | |
432 | if (opts == NULL) | |
433 | goto nla_put_failure; | |
434 | ||
435 | if (nla_put_u32(skb, TCA_FQ_CODEL_TARGET, | |
436 | codel_time_to_us(q->cparams.target)) || | |
437 | nla_put_u32(skb, TCA_FQ_CODEL_LIMIT, | |
438 | sch->limit) || | |
439 | nla_put_u32(skb, TCA_FQ_CODEL_INTERVAL, | |
440 | codel_time_to_us(q->cparams.interval)) || | |
441 | nla_put_u32(skb, TCA_FQ_CODEL_ECN, | |
442 | q->cparams.ecn) || | |
443 | nla_put_u32(skb, TCA_FQ_CODEL_QUANTUM, | |
444 | q->quantum) || | |
445 | nla_put_u32(skb, TCA_FQ_CODEL_FLOWS, | |
446 | q->flows_cnt)) | |
447 | goto nla_put_failure; | |
448 | ||
d59b7d80 | 449 | return nla_nest_end(skb, opts); |
4b549a2e ED |
450 | |
451 | nla_put_failure: | |
452 | return -1; | |
453 | } | |
454 | ||
455 | static int fq_codel_dump_stats(struct Qdisc *sch, struct gnet_dump *d) | |
456 | { | |
457 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
458 | struct tc_fq_codel_xstats st = { | |
459 | .type = TCA_FQ_CODEL_XSTATS_QDISC, | |
4b549a2e ED |
460 | }; |
461 | struct list_head *pos; | |
462 | ||
669d67bf SL |
463 | st.qdisc_stats.maxpacket = q->cstats.maxpacket; |
464 | st.qdisc_stats.drop_overlimit = q->drop_overlimit; | |
465 | st.qdisc_stats.ecn_mark = q->cstats.ecn_mark; | |
466 | st.qdisc_stats.new_flow_count = q->new_flow_count; | |
467 | ||
4b549a2e ED |
468 | list_for_each(pos, &q->new_flows) |
469 | st.qdisc_stats.new_flows_len++; | |
470 | ||
471 | list_for_each(pos, &q->old_flows) | |
472 | st.qdisc_stats.old_flows_len++; | |
473 | ||
474 | return gnet_stats_copy_app(d, &st, sizeof(st)); | |
475 | } | |
476 | ||
477 | static struct Qdisc *fq_codel_leaf(struct Qdisc *sch, unsigned long arg) | |
478 | { | |
479 | return NULL; | |
480 | } | |
481 | ||
482 | static unsigned long fq_codel_get(struct Qdisc *sch, u32 classid) | |
483 | { | |
484 | return 0; | |
485 | } | |
486 | ||
487 | static unsigned long fq_codel_bind(struct Qdisc *sch, unsigned long parent, | |
488 | u32 classid) | |
489 | { | |
490 | /* we cannot bypass queue discipline anymore */ | |
491 | sch->flags &= ~TCQ_F_CAN_BYPASS; | |
492 | return 0; | |
493 | } | |
494 | ||
495 | static void fq_codel_put(struct Qdisc *q, unsigned long cl) | |
496 | { | |
497 | } | |
498 | ||
499 | static struct tcf_proto **fq_codel_find_tcf(struct Qdisc *sch, unsigned long cl) | |
500 | { | |
501 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
502 | ||
503 | if (cl) | |
504 | return NULL; | |
505 | return &q->filter_list; | |
506 | } | |
507 | ||
508 | static int fq_codel_dump_class(struct Qdisc *sch, unsigned long cl, | |
509 | struct sk_buff *skb, struct tcmsg *tcm) | |
510 | { | |
511 | tcm->tcm_handle |= TC_H_MIN(cl); | |
512 | return 0; | |
513 | } | |
514 | ||
515 | static int fq_codel_dump_class_stats(struct Qdisc *sch, unsigned long cl, | |
516 | struct gnet_dump *d) | |
517 | { | |
518 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
519 | u32 idx = cl - 1; | |
520 | struct gnet_stats_queue qs = { 0 }; | |
521 | struct tc_fq_codel_xstats xstats; | |
522 | ||
523 | if (idx < q->flows_cnt) { | |
524 | const struct fq_codel_flow *flow = &q->flows[idx]; | |
525 | const struct sk_buff *skb = flow->head; | |
526 | ||
527 | memset(&xstats, 0, sizeof(xstats)); | |
528 | xstats.type = TCA_FQ_CODEL_XSTATS_CLASS; | |
529 | xstats.class_stats.deficit = flow->deficit; | |
530 | xstats.class_stats.ldelay = | |
531 | codel_time_to_us(flow->cvars.ldelay); | |
532 | xstats.class_stats.count = flow->cvars.count; | |
533 | xstats.class_stats.lastcount = flow->cvars.lastcount; | |
534 | xstats.class_stats.dropping = flow->cvars.dropping; | |
535 | if (flow->cvars.dropping) { | |
536 | codel_tdiff_t delta = flow->cvars.drop_next - | |
537 | codel_get_time(); | |
538 | ||
539 | xstats.class_stats.drop_next = (delta >= 0) ? | |
540 | codel_time_to_us(delta) : | |
541 | -codel_time_to_us(-delta); | |
542 | } | |
543 | while (skb) { | |
544 | qs.qlen++; | |
545 | skb = skb->next; | |
546 | } | |
547 | qs.backlog = q->backlogs[idx]; | |
548 | qs.drops = flow->dropped; | |
549 | } | |
550 | if (gnet_stats_copy_queue(d, &qs) < 0) | |
551 | return -1; | |
552 | if (idx < q->flows_cnt) | |
553 | return gnet_stats_copy_app(d, &xstats, sizeof(xstats)); | |
554 | return 0; | |
555 | } | |
556 | ||
557 | static void fq_codel_walk(struct Qdisc *sch, struct qdisc_walker *arg) | |
558 | { | |
559 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
560 | unsigned int i; | |
561 | ||
562 | if (arg->stop) | |
563 | return; | |
564 | ||
565 | for (i = 0; i < q->flows_cnt; i++) { | |
566 | if (list_empty(&q->flows[i].flowchain) || | |
567 | arg->count < arg->skip) { | |
568 | arg->count++; | |
569 | continue; | |
570 | } | |
571 | if (arg->fn(sch, i + 1, arg) < 0) { | |
572 | arg->stop = 1; | |
573 | break; | |
574 | } | |
575 | arg->count++; | |
576 | } | |
577 | } | |
578 | ||
579 | static const struct Qdisc_class_ops fq_codel_class_ops = { | |
580 | .leaf = fq_codel_leaf, | |
581 | .get = fq_codel_get, | |
582 | .put = fq_codel_put, | |
583 | .tcf_chain = fq_codel_find_tcf, | |
584 | .bind_tcf = fq_codel_bind, | |
585 | .unbind_tcf = fq_codel_put, | |
586 | .dump = fq_codel_dump_class, | |
587 | .dump_stats = fq_codel_dump_class_stats, | |
588 | .walk = fq_codel_walk, | |
589 | }; | |
590 | ||
591 | static struct Qdisc_ops fq_codel_qdisc_ops __read_mostly = { | |
592 | .cl_ops = &fq_codel_class_ops, | |
593 | .id = "fq_codel", | |
594 | .priv_size = sizeof(struct fq_codel_sched_data), | |
595 | .enqueue = fq_codel_enqueue, | |
596 | .dequeue = fq_codel_dequeue, | |
597 | .peek = qdisc_peek_dequeued, | |
598 | .drop = fq_codel_drop, | |
599 | .init = fq_codel_init, | |
600 | .reset = fq_codel_reset, | |
601 | .destroy = fq_codel_destroy, | |
602 | .change = fq_codel_change, | |
603 | .dump = fq_codel_dump, | |
604 | .dump_stats = fq_codel_dump_stats, | |
605 | .owner = THIS_MODULE, | |
606 | }; | |
607 | ||
608 | static int __init fq_codel_module_init(void) | |
609 | { | |
610 | return register_qdisc(&fq_codel_qdisc_ops); | |
611 | } | |
612 | ||
613 | static void __exit fq_codel_module_exit(void) | |
614 | { | |
615 | unregister_qdisc(&fq_codel_qdisc_ops); | |
616 | } | |
617 | ||
618 | module_init(fq_codel_module_init) | |
619 | module_exit(fq_codel_module_exit) | |
620 | MODULE_AUTHOR("Eric Dumazet"); | |
621 | MODULE_LICENSE("GPL"); |