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Commit | Line | Data |
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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 | * | |
80ba92fa | 9 | * Copyright (C) 2012,2015 Eric Dumazet <edumazet@google.com> |
4b549a2e ED |
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> | |
4b549a2e | 26 | #include <net/codel.h> |
d068ca2a MK |
27 | #include <net/codel_impl.h> |
28 | #include <net/codel_qdisc.h> | |
4b549a2e ED |
29 | |
30 | /* Fair Queue CoDel. | |
31 | * | |
32 | * Principles : | |
33 | * Packets are classified (internal classifier or external) on flows. | |
34 | * This is a Stochastic model (as we use a hash, several flows | |
35 | * might be hashed on same slot) | |
36 | * Each flow has a CoDel managed queue. | |
37 | * Flows are linked onto two (Round Robin) lists, | |
38 | * so that new flows have priority on old ones. | |
39 | * | |
40 | * For a given flow, packets are not reordered (CoDel uses a FIFO) | |
41 | * head drops only. | |
42 | * ECN capability is on by default. | |
43 | * Low memory footprint (64 bytes per flow) | |
44 | */ | |
45 | ||
46 | struct fq_codel_flow { | |
47 | struct sk_buff *head; | |
48 | struct sk_buff *tail; | |
49 | struct list_head flowchain; | |
50 | int deficit; | |
51 | u32 dropped; /* number of drops (or ECN marks) on this flow */ | |
52 | struct codel_vars cvars; | |
53 | }; /* please try to keep this structure <= 64 bytes */ | |
54 | ||
55 | struct fq_codel_sched_data { | |
25d8c0d5 | 56 | struct tcf_proto __rcu *filter_list; /* optional external classifier */ |
4b549a2e ED |
57 | struct fq_codel_flow *flows; /* Flows table [flows_cnt] */ |
58 | u32 *backlogs; /* backlog table [flows_cnt] */ | |
59 | u32 flows_cnt; /* number of flows */ | |
60 | u32 perturbation; /* hash perturbation */ | |
61 | u32 quantum; /* psched_mtu(qdisc_dev(sch)); */ | |
9d18562a | 62 | u32 drop_batch_size; |
95b58430 | 63 | u32 memory_limit; |
4b549a2e ED |
64 | struct codel_params cparams; |
65 | struct codel_stats cstats; | |
95b58430 ED |
66 | u32 memory_usage; |
67 | u32 drop_overmemory; | |
4b549a2e ED |
68 | u32 drop_overlimit; |
69 | u32 new_flow_count; | |
70 | ||
71 | struct list_head new_flows; /* list of new flows */ | |
72 | struct list_head old_flows; /* list of old flows */ | |
73 | }; | |
74 | ||
75 | static unsigned int fq_codel_hash(const struct fq_codel_sched_data *q, | |
342db221 | 76 | struct sk_buff *skb) |
4b549a2e | 77 | { |
342db221 | 78 | u32 hash = skb_get_hash_perturb(skb, q->perturbation); |
8fc54f68 DB |
79 | |
80 | return reciprocal_scale(hash, q->flows_cnt); | |
4b549a2e ED |
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); | |
25d8c0d5 | 87 | struct tcf_proto *filter; |
4b549a2e ED |
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 | ||
69204cf7 | 96 | filter = rcu_dereference_bh(q->filter_list); |
25d8c0d5 | 97 | if (!filter) |
4b549a2e ED |
98 | return fq_codel_hash(q, skb) + 1; |
99 | ||
100 | *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS; | |
3b3ae880 | 101 | result = tc_classify(skb, filter, &res, false); |
4b549a2e ED |
102 | if (result >= 0) { |
103 | #ifdef CONFIG_NET_CLS_ACT | |
104 | switch (result) { | |
105 | case TC_ACT_STOLEN: | |
106 | case TC_ACT_QUEUED: | |
107 | *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN; | |
108 | case TC_ACT_SHOT: | |
109 | return 0; | |
110 | } | |
111 | #endif | |
112 | if (TC_H_MIN(res.classid) <= q->flows_cnt) | |
113 | return TC_H_MIN(res.classid); | |
114 | } | |
115 | return 0; | |
116 | } | |
117 | ||
118 | /* helper functions : might be changed when/if skb use a standard list_head */ | |
119 | ||
120 | /* remove one skb from head of slot queue */ | |
121 | static inline struct sk_buff *dequeue_head(struct fq_codel_flow *flow) | |
122 | { | |
123 | struct sk_buff *skb = flow->head; | |
124 | ||
125 | flow->head = skb->next; | |
126 | skb->next = NULL; | |
127 | return skb; | |
128 | } | |
129 | ||
130 | /* add skb to flow queue (tail add) */ | |
131 | static inline void flow_queue_add(struct fq_codel_flow *flow, | |
132 | struct sk_buff *skb) | |
133 | { | |
134 | if (flow->head == NULL) | |
135 | flow->head = skb; | |
136 | else | |
137 | flow->tail->next = skb; | |
138 | flow->tail = skb; | |
139 | skb->next = NULL; | |
140 | } | |
141 | ||
9d18562a | 142 | static unsigned int fq_codel_drop(struct Qdisc *sch, unsigned int max_packets) |
4b549a2e ED |
143 | { |
144 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
145 | struct sk_buff *skb; | |
146 | unsigned int maxbacklog = 0, idx = 0, i, len; | |
147 | struct fq_codel_flow *flow; | |
9d18562a | 148 | unsigned int threshold; |
95b58430 | 149 | unsigned int mem = 0; |
4b549a2e | 150 | |
9d18562a | 151 | /* Queue is full! Find the fat flow and drop packet(s) from it. |
4b549a2e ED |
152 | * This might sound expensive, but with 1024 flows, we scan |
153 | * 4KB of memory, and we dont need to handle a complex tree | |
154 | * in fast path (packet queue/enqueue) with many cache misses. | |
9d18562a ED |
155 | * In stress mode, we'll try to drop 64 packets from the flow, |
156 | * amortizing this linear lookup to one cache line per drop. | |
4b549a2e ED |
157 | */ |
158 | for (i = 0; i < q->flows_cnt; i++) { | |
159 | if (q->backlogs[i] > maxbacklog) { | |
160 | maxbacklog = q->backlogs[i]; | |
161 | idx = i; | |
162 | } | |
163 | } | |
9d18562a ED |
164 | |
165 | /* Our goal is to drop half of this fat flow backlog */ | |
166 | threshold = maxbacklog >> 1; | |
167 | ||
4b549a2e | 168 | flow = &q->flows[idx]; |
9d18562a ED |
169 | len = 0; |
170 | i = 0; | |
171 | do { | |
172 | skb = dequeue_head(flow); | |
173 | len += qdisc_pkt_len(skb); | |
95b58430 | 174 | mem += skb->truesize; |
9d18562a ED |
175 | kfree_skb(skb); |
176 | } while (++i < max_packets && len < threshold); | |
177 | ||
178 | flow->dropped += i; | |
4b549a2e | 179 | q->backlogs[idx] -= len; |
95b58430 | 180 | q->memory_usage -= mem; |
9d18562a ED |
181 | sch->qstats.drops += i; |
182 | sch->qstats.backlog -= len; | |
183 | sch->q.qlen -= i; | |
4b549a2e ED |
184 | return idx; |
185 | } | |
186 | ||
c0afd9ce WC |
187 | static unsigned int fq_codel_qdisc_drop(struct Qdisc *sch) |
188 | { | |
189 | unsigned int prev_backlog; | |
190 | ||
191 | prev_backlog = sch->qstats.backlog; | |
9d18562a | 192 | fq_codel_drop(sch, 1U); |
c0afd9ce WC |
193 | return prev_backlog - sch->qstats.backlog; |
194 | } | |
195 | ||
4b549a2e ED |
196 | static int fq_codel_enqueue(struct sk_buff *skb, struct Qdisc *sch) |
197 | { | |
198 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
9d18562a | 199 | unsigned int idx, prev_backlog, prev_qlen; |
4b549a2e ED |
200 | struct fq_codel_flow *flow; |
201 | int uninitialized_var(ret); | |
80e509db | 202 | unsigned int pkt_len; |
95b58430 | 203 | bool memory_limited; |
4b549a2e ED |
204 | |
205 | idx = fq_codel_classify(skb, sch, &ret); | |
206 | if (idx == 0) { | |
207 | if (ret & __NET_XMIT_BYPASS) | |
25331d6c | 208 | qdisc_qstats_drop(sch); |
4b549a2e ED |
209 | kfree_skb(skb); |
210 | return ret; | |
211 | } | |
212 | idx--; | |
213 | ||
214 | codel_set_enqueue_time(skb); | |
215 | flow = &q->flows[idx]; | |
216 | flow_queue_add(flow, skb); | |
217 | q->backlogs[idx] += qdisc_pkt_len(skb); | |
25331d6c | 218 | qdisc_qstats_backlog_inc(sch, skb); |
4b549a2e ED |
219 | |
220 | if (list_empty(&flow->flowchain)) { | |
221 | list_add_tail(&flow->flowchain, &q->new_flows); | |
4b549a2e ED |
222 | q->new_flow_count++; |
223 | flow->deficit = q->quantum; | |
224 | flow->dropped = 0; | |
225 | } | |
95b58430 ED |
226 | q->memory_usage += skb->truesize; |
227 | memory_limited = q->memory_usage > q->memory_limit; | |
228 | if (++sch->q.qlen <= sch->limit && !memory_limited) | |
4b549a2e ED |
229 | return NET_XMIT_SUCCESS; |
230 | ||
2ccccf5f | 231 | prev_backlog = sch->qstats.backlog; |
9d18562a ED |
232 | prev_qlen = sch->q.qlen; |
233 | ||
80e509db ED |
234 | /* save this packet length as it might be dropped by fq_codel_drop() */ |
235 | pkt_len = qdisc_pkt_len(skb); | |
9d18562a ED |
236 | /* fq_codel_drop() is quite expensive, as it performs a linear search |
237 | * in q->backlogs[] to find a fat flow. | |
238 | * So instead of dropping a single packet, drop half of its backlog | |
239 | * with a 64 packets limit to not add a too big cpu spike here. | |
4b549a2e | 240 | */ |
9d18562a ED |
241 | ret = fq_codel_drop(sch, q->drop_batch_size); |
242 | ||
80e509db ED |
243 | prev_qlen -= sch->q.qlen; |
244 | prev_backlog -= sch->qstats.backlog; | |
245 | q->drop_overlimit += prev_qlen; | |
95b58430 | 246 | if (memory_limited) |
80e509db | 247 | q->drop_overmemory += prev_qlen; |
9d18562a | 248 | |
80e509db ED |
249 | /* As we dropped packet(s), better let upper stack know this. |
250 | * If we dropped a packet for this flow, return NET_XMIT_CN, | |
251 | * but in this case, our parents wont increase their backlogs. | |
252 | */ | |
253 | if (ret == idx) { | |
254 | qdisc_tree_reduce_backlog(sch, prev_qlen - 1, | |
255 | prev_backlog - pkt_len); | |
256 | return NET_XMIT_CN; | |
257 | } | |
258 | qdisc_tree_reduce_backlog(sch, prev_qlen, prev_backlog); | |
259 | return NET_XMIT_SUCCESS; | |
4b549a2e ED |
260 | } |
261 | ||
262 | /* This is the specific function called from codel_dequeue() | |
263 | * to dequeue a packet from queue. Note: backlog is handled in | |
264 | * codel, we dont need to reduce it here. | |
265 | */ | |
79bdc4c8 | 266 | static struct sk_buff *dequeue_func(struct codel_vars *vars, void *ctx) |
4b549a2e | 267 | { |
79bdc4c8 | 268 | struct Qdisc *sch = ctx; |
865ec552 | 269 | struct fq_codel_sched_data *q = qdisc_priv(sch); |
4b549a2e ED |
270 | struct fq_codel_flow *flow; |
271 | struct sk_buff *skb = NULL; | |
272 | ||
273 | flow = container_of(vars, struct fq_codel_flow, cvars); | |
274 | if (flow->head) { | |
275 | skb = dequeue_head(flow); | |
865ec552 | 276 | q->backlogs[flow - q->flows] -= qdisc_pkt_len(skb); |
77f57761 | 277 | q->memory_usage -= skb->truesize; |
4b549a2e | 278 | sch->q.qlen--; |
79bdc4c8 | 279 | sch->qstats.backlog -= qdisc_pkt_len(skb); |
4b549a2e ED |
280 | } |
281 | return skb; | |
282 | } | |
283 | ||
79bdc4c8 MK |
284 | static void drop_func(struct sk_buff *skb, void *ctx) |
285 | { | |
286 | struct Qdisc *sch = ctx; | |
287 | ||
288 | qdisc_drop(skb, sch); | |
289 | } | |
290 | ||
4b549a2e ED |
291 | static struct sk_buff *fq_codel_dequeue(struct Qdisc *sch) |
292 | { | |
293 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
294 | struct sk_buff *skb; | |
295 | struct fq_codel_flow *flow; | |
296 | struct list_head *head; | |
297 | u32 prev_drop_count, prev_ecn_mark; | |
2ccccf5f | 298 | unsigned int prev_backlog; |
4b549a2e ED |
299 | |
300 | begin: | |
301 | head = &q->new_flows; | |
302 | if (list_empty(head)) { | |
303 | head = &q->old_flows; | |
304 | if (list_empty(head)) | |
305 | return NULL; | |
306 | } | |
307 | flow = list_first_entry(head, struct fq_codel_flow, flowchain); | |
308 | ||
309 | if (flow->deficit <= 0) { | |
310 | flow->deficit += q->quantum; | |
311 | list_move_tail(&flow->flowchain, &q->old_flows); | |
312 | goto begin; | |
313 | } | |
314 | ||
315 | prev_drop_count = q->cstats.drop_count; | |
316 | prev_ecn_mark = q->cstats.ecn_mark; | |
2ccccf5f | 317 | prev_backlog = sch->qstats.backlog; |
4b549a2e | 318 | |
79bdc4c8 MK |
319 | skb = codel_dequeue(sch, &sch->qstats.backlog, &q->cparams, |
320 | &flow->cvars, &q->cstats, qdisc_pkt_len, | |
321 | codel_get_enqueue_time, drop_func, dequeue_func); | |
4b549a2e ED |
322 | |
323 | flow->dropped += q->cstats.drop_count - prev_drop_count; | |
324 | flow->dropped += q->cstats.ecn_mark - prev_ecn_mark; | |
325 | ||
326 | if (!skb) { | |
327 | /* force a pass through old_flows to prevent starvation */ | |
328 | if ((head == &q->new_flows) && !list_empty(&q->old_flows)) | |
329 | list_move_tail(&flow->flowchain, &q->old_flows); | |
330 | else | |
331 | list_del_init(&flow->flowchain); | |
332 | goto begin; | |
333 | } | |
334 | qdisc_bstats_update(sch, skb); | |
335 | flow->deficit -= qdisc_pkt_len(skb); | |
2ccccf5f | 336 | /* We cant call qdisc_tree_reduce_backlog() if our qlen is 0, |
4b549a2e ED |
337 | * or HTB crashes. Defer it for next round. |
338 | */ | |
339 | if (q->cstats.drop_count && sch->q.qlen) { | |
2ccccf5f WC |
340 | qdisc_tree_reduce_backlog(sch, q->cstats.drop_count, |
341 | q->cstats.drop_len); | |
4b549a2e | 342 | q->cstats.drop_count = 0; |
2ccccf5f | 343 | q->cstats.drop_len = 0; |
4b549a2e ED |
344 | } |
345 | return skb; | |
346 | } | |
347 | ||
348 | static void fq_codel_reset(struct Qdisc *sch) | |
349 | { | |
3d0e0af4 ED |
350 | struct fq_codel_sched_data *q = qdisc_priv(sch); |
351 | int i; | |
4b549a2e | 352 | |
3d0e0af4 ED |
353 | INIT_LIST_HEAD(&q->new_flows); |
354 | INIT_LIST_HEAD(&q->old_flows); | |
355 | for (i = 0; i < q->flows_cnt; i++) { | |
356 | struct fq_codel_flow *flow = q->flows + i; | |
357 | ||
358 | while (flow->head) { | |
359 | struct sk_buff *skb = dequeue_head(flow); | |
360 | ||
361 | qdisc_qstats_backlog_dec(sch, skb); | |
362 | kfree_skb(skb); | |
363 | } | |
364 | ||
365 | INIT_LIST_HEAD(&flow->flowchain); | |
366 | codel_vars_init(&flow->cvars); | |
367 | } | |
368 | memset(q->backlogs, 0, q->flows_cnt * sizeof(u32)); | |
369 | sch->q.qlen = 0; | |
77f57761 | 370 | q->memory_usage = 0; |
4b549a2e ED |
371 | } |
372 | ||
373 | static const struct nla_policy fq_codel_policy[TCA_FQ_CODEL_MAX + 1] = { | |
374 | [TCA_FQ_CODEL_TARGET] = { .type = NLA_U32 }, | |
375 | [TCA_FQ_CODEL_LIMIT] = { .type = NLA_U32 }, | |
376 | [TCA_FQ_CODEL_INTERVAL] = { .type = NLA_U32 }, | |
377 | [TCA_FQ_CODEL_ECN] = { .type = NLA_U32 }, | |
378 | [TCA_FQ_CODEL_FLOWS] = { .type = NLA_U32 }, | |
379 | [TCA_FQ_CODEL_QUANTUM] = { .type = NLA_U32 }, | |
80ba92fa | 380 | [TCA_FQ_CODEL_CE_THRESHOLD] = { .type = NLA_U32 }, |
9d18562a | 381 | [TCA_FQ_CODEL_DROP_BATCH_SIZE] = { .type = NLA_U32 }, |
95b58430 | 382 | [TCA_FQ_CODEL_MEMORY_LIMIT] = { .type = NLA_U32 }, |
4b549a2e ED |
383 | }; |
384 | ||
385 | static int fq_codel_change(struct Qdisc *sch, struct nlattr *opt) | |
386 | { | |
387 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
388 | struct nlattr *tb[TCA_FQ_CODEL_MAX + 1]; | |
389 | int err; | |
390 | ||
391 | if (!opt) | |
392 | return -EINVAL; | |
393 | ||
394 | err = nla_parse_nested(tb, TCA_FQ_CODEL_MAX, opt, fq_codel_policy); | |
395 | if (err < 0) | |
396 | return err; | |
397 | if (tb[TCA_FQ_CODEL_FLOWS]) { | |
398 | if (q->flows) | |
399 | return -EINVAL; | |
400 | q->flows_cnt = nla_get_u32(tb[TCA_FQ_CODEL_FLOWS]); | |
401 | if (!q->flows_cnt || | |
402 | q->flows_cnt > 65536) | |
403 | return -EINVAL; | |
404 | } | |
405 | sch_tree_lock(sch); | |
406 | ||
407 | if (tb[TCA_FQ_CODEL_TARGET]) { | |
408 | u64 target = nla_get_u32(tb[TCA_FQ_CODEL_TARGET]); | |
409 | ||
410 | q->cparams.target = (target * NSEC_PER_USEC) >> CODEL_SHIFT; | |
411 | } | |
412 | ||
80ba92fa ED |
413 | if (tb[TCA_FQ_CODEL_CE_THRESHOLD]) { |
414 | u64 val = nla_get_u32(tb[TCA_FQ_CODEL_CE_THRESHOLD]); | |
415 | ||
416 | q->cparams.ce_threshold = (val * NSEC_PER_USEC) >> CODEL_SHIFT; | |
417 | } | |
418 | ||
4b549a2e ED |
419 | if (tb[TCA_FQ_CODEL_INTERVAL]) { |
420 | u64 interval = nla_get_u32(tb[TCA_FQ_CODEL_INTERVAL]); | |
421 | ||
422 | q->cparams.interval = (interval * NSEC_PER_USEC) >> CODEL_SHIFT; | |
423 | } | |
424 | ||
425 | if (tb[TCA_FQ_CODEL_LIMIT]) | |
426 | sch->limit = nla_get_u32(tb[TCA_FQ_CODEL_LIMIT]); | |
427 | ||
428 | if (tb[TCA_FQ_CODEL_ECN]) | |
429 | q->cparams.ecn = !!nla_get_u32(tb[TCA_FQ_CODEL_ECN]); | |
430 | ||
431 | if (tb[TCA_FQ_CODEL_QUANTUM]) | |
432 | q->quantum = max(256U, nla_get_u32(tb[TCA_FQ_CODEL_QUANTUM])); | |
433 | ||
9d18562a ED |
434 | if (tb[TCA_FQ_CODEL_DROP_BATCH_SIZE]) |
435 | q->drop_batch_size = min(1U, nla_get_u32(tb[TCA_FQ_CODEL_DROP_BATCH_SIZE])); | |
436 | ||
95b58430 ED |
437 | if (tb[TCA_FQ_CODEL_MEMORY_LIMIT]) |
438 | q->memory_limit = min(1U << 31, nla_get_u32(tb[TCA_FQ_CODEL_MEMORY_LIMIT])); | |
439 | ||
440 | while (sch->q.qlen > sch->limit || | |
441 | q->memory_usage > q->memory_limit) { | |
4b549a2e ED |
442 | struct sk_buff *skb = fq_codel_dequeue(sch); |
443 | ||
2ccccf5f | 444 | q->cstats.drop_len += qdisc_pkt_len(skb); |
4b549a2e ED |
445 | kfree_skb(skb); |
446 | q->cstats.drop_count++; | |
447 | } | |
2ccccf5f | 448 | qdisc_tree_reduce_backlog(sch, q->cstats.drop_count, q->cstats.drop_len); |
4b549a2e | 449 | q->cstats.drop_count = 0; |
2ccccf5f | 450 | q->cstats.drop_len = 0; |
4b549a2e ED |
451 | |
452 | sch_tree_unlock(sch); | |
453 | return 0; | |
454 | } | |
455 | ||
456 | static void *fq_codel_zalloc(size_t sz) | |
457 | { | |
458 | void *ptr = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN); | |
459 | ||
460 | if (!ptr) | |
461 | ptr = vzalloc(sz); | |
462 | return ptr; | |
463 | } | |
464 | ||
465 | static void fq_codel_free(void *addr) | |
466 | { | |
4cb28970 | 467 | kvfree(addr); |
4b549a2e ED |
468 | } |
469 | ||
470 | static void fq_codel_destroy(struct Qdisc *sch) | |
471 | { | |
472 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
473 | ||
474 | tcf_destroy_chain(&q->filter_list); | |
475 | fq_codel_free(q->backlogs); | |
476 | fq_codel_free(q->flows); | |
477 | } | |
478 | ||
479 | static int fq_codel_init(struct Qdisc *sch, struct nlattr *opt) | |
480 | { | |
481 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
482 | int i; | |
483 | ||
484 | sch->limit = 10*1024; | |
485 | q->flows_cnt = 1024; | |
95b58430 | 486 | q->memory_limit = 32 << 20; /* 32 MBytes */ |
9d18562a | 487 | q->drop_batch_size = 64; |
4b549a2e | 488 | q->quantum = psched_mtu(qdisc_dev(sch)); |
63862b5b | 489 | q->perturbation = prandom_u32(); |
4b549a2e ED |
490 | INIT_LIST_HEAD(&q->new_flows); |
491 | INIT_LIST_HEAD(&q->old_flows); | |
79bdc4c8 | 492 | codel_params_init(&q->cparams); |
4b549a2e ED |
493 | codel_stats_init(&q->cstats); |
494 | q->cparams.ecn = true; | |
79bdc4c8 | 495 | q->cparams.mtu = psched_mtu(qdisc_dev(sch)); |
4b549a2e ED |
496 | |
497 | if (opt) { | |
498 | int err = fq_codel_change(sch, opt); | |
499 | if (err) | |
500 | return err; | |
501 | } | |
502 | ||
503 | if (!q->flows) { | |
504 | q->flows = fq_codel_zalloc(q->flows_cnt * | |
505 | sizeof(struct fq_codel_flow)); | |
506 | if (!q->flows) | |
507 | return -ENOMEM; | |
508 | q->backlogs = fq_codel_zalloc(q->flows_cnt * sizeof(u32)); | |
509 | if (!q->backlogs) { | |
510 | fq_codel_free(q->flows); | |
511 | return -ENOMEM; | |
512 | } | |
513 | for (i = 0; i < q->flows_cnt; i++) { | |
514 | struct fq_codel_flow *flow = q->flows + i; | |
515 | ||
516 | INIT_LIST_HEAD(&flow->flowchain); | |
b379135c | 517 | codel_vars_init(&flow->cvars); |
4b549a2e ED |
518 | } |
519 | } | |
520 | if (sch->limit >= 1) | |
521 | sch->flags |= TCQ_F_CAN_BYPASS; | |
522 | else | |
523 | sch->flags &= ~TCQ_F_CAN_BYPASS; | |
524 | return 0; | |
525 | } | |
526 | ||
527 | static int fq_codel_dump(struct Qdisc *sch, struct sk_buff *skb) | |
528 | { | |
529 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
530 | struct nlattr *opts; | |
531 | ||
532 | opts = nla_nest_start(skb, TCA_OPTIONS); | |
533 | if (opts == NULL) | |
534 | goto nla_put_failure; | |
535 | ||
536 | if (nla_put_u32(skb, TCA_FQ_CODEL_TARGET, | |
537 | codel_time_to_us(q->cparams.target)) || | |
538 | nla_put_u32(skb, TCA_FQ_CODEL_LIMIT, | |
539 | sch->limit) || | |
540 | nla_put_u32(skb, TCA_FQ_CODEL_INTERVAL, | |
541 | codel_time_to_us(q->cparams.interval)) || | |
542 | nla_put_u32(skb, TCA_FQ_CODEL_ECN, | |
543 | q->cparams.ecn) || | |
544 | nla_put_u32(skb, TCA_FQ_CODEL_QUANTUM, | |
545 | q->quantum) || | |
9d18562a ED |
546 | nla_put_u32(skb, TCA_FQ_CODEL_DROP_BATCH_SIZE, |
547 | q->drop_batch_size) || | |
95b58430 ED |
548 | nla_put_u32(skb, TCA_FQ_CODEL_MEMORY_LIMIT, |
549 | q->memory_limit) || | |
4b549a2e ED |
550 | nla_put_u32(skb, TCA_FQ_CODEL_FLOWS, |
551 | q->flows_cnt)) | |
552 | goto nla_put_failure; | |
553 | ||
80ba92fa ED |
554 | if (q->cparams.ce_threshold != CODEL_DISABLED_THRESHOLD && |
555 | nla_put_u32(skb, TCA_FQ_CODEL_CE_THRESHOLD, | |
556 | codel_time_to_us(q->cparams.ce_threshold))) | |
557 | goto nla_put_failure; | |
558 | ||
d59b7d80 | 559 | return nla_nest_end(skb, opts); |
4b549a2e ED |
560 | |
561 | nla_put_failure: | |
562 | return -1; | |
563 | } | |
564 | ||
565 | static int fq_codel_dump_stats(struct Qdisc *sch, struct gnet_dump *d) | |
566 | { | |
567 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
568 | struct tc_fq_codel_xstats st = { | |
569 | .type = TCA_FQ_CODEL_XSTATS_QDISC, | |
4b549a2e ED |
570 | }; |
571 | struct list_head *pos; | |
572 | ||
669d67bf SL |
573 | st.qdisc_stats.maxpacket = q->cstats.maxpacket; |
574 | st.qdisc_stats.drop_overlimit = q->drop_overlimit; | |
575 | st.qdisc_stats.ecn_mark = q->cstats.ecn_mark; | |
576 | st.qdisc_stats.new_flow_count = q->new_flow_count; | |
80ba92fa | 577 | st.qdisc_stats.ce_mark = q->cstats.ce_mark; |
95b58430 ED |
578 | st.qdisc_stats.memory_usage = q->memory_usage; |
579 | st.qdisc_stats.drop_overmemory = q->drop_overmemory; | |
669d67bf | 580 | |
4b549a2e ED |
581 | list_for_each(pos, &q->new_flows) |
582 | st.qdisc_stats.new_flows_len++; | |
583 | ||
584 | list_for_each(pos, &q->old_flows) | |
585 | st.qdisc_stats.old_flows_len++; | |
586 | ||
587 | return gnet_stats_copy_app(d, &st, sizeof(st)); | |
588 | } | |
589 | ||
590 | static struct Qdisc *fq_codel_leaf(struct Qdisc *sch, unsigned long arg) | |
591 | { | |
592 | return NULL; | |
593 | } | |
594 | ||
595 | static unsigned long fq_codel_get(struct Qdisc *sch, u32 classid) | |
596 | { | |
597 | return 0; | |
598 | } | |
599 | ||
600 | static unsigned long fq_codel_bind(struct Qdisc *sch, unsigned long parent, | |
601 | u32 classid) | |
602 | { | |
603 | /* we cannot bypass queue discipline anymore */ | |
604 | sch->flags &= ~TCQ_F_CAN_BYPASS; | |
605 | return 0; | |
606 | } | |
607 | ||
608 | static void fq_codel_put(struct Qdisc *q, unsigned long cl) | |
609 | { | |
610 | } | |
611 | ||
25d8c0d5 JF |
612 | static struct tcf_proto __rcu **fq_codel_find_tcf(struct Qdisc *sch, |
613 | unsigned long cl) | |
4b549a2e ED |
614 | { |
615 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
616 | ||
617 | if (cl) | |
618 | return NULL; | |
619 | return &q->filter_list; | |
620 | } | |
621 | ||
622 | static int fq_codel_dump_class(struct Qdisc *sch, unsigned long cl, | |
623 | struct sk_buff *skb, struct tcmsg *tcm) | |
624 | { | |
625 | tcm->tcm_handle |= TC_H_MIN(cl); | |
626 | return 0; | |
627 | } | |
628 | ||
629 | static int fq_codel_dump_class_stats(struct Qdisc *sch, unsigned long cl, | |
630 | struct gnet_dump *d) | |
631 | { | |
632 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
633 | u32 idx = cl - 1; | |
634 | struct gnet_stats_queue qs = { 0 }; | |
635 | struct tc_fq_codel_xstats xstats; | |
636 | ||
637 | if (idx < q->flows_cnt) { | |
638 | const struct fq_codel_flow *flow = &q->flows[idx]; | |
639 | const struct sk_buff *skb = flow->head; | |
640 | ||
641 | memset(&xstats, 0, sizeof(xstats)); | |
642 | xstats.type = TCA_FQ_CODEL_XSTATS_CLASS; | |
643 | xstats.class_stats.deficit = flow->deficit; | |
644 | xstats.class_stats.ldelay = | |
645 | codel_time_to_us(flow->cvars.ldelay); | |
646 | xstats.class_stats.count = flow->cvars.count; | |
647 | xstats.class_stats.lastcount = flow->cvars.lastcount; | |
648 | xstats.class_stats.dropping = flow->cvars.dropping; | |
649 | if (flow->cvars.dropping) { | |
650 | codel_tdiff_t delta = flow->cvars.drop_next - | |
651 | codel_get_time(); | |
652 | ||
653 | xstats.class_stats.drop_next = (delta >= 0) ? | |
654 | codel_time_to_us(delta) : | |
655 | -codel_time_to_us(-delta); | |
656 | } | |
657 | while (skb) { | |
658 | qs.qlen++; | |
659 | skb = skb->next; | |
660 | } | |
661 | qs.backlog = q->backlogs[idx]; | |
662 | qs.drops = flow->dropped; | |
663 | } | |
aafddbf0 | 664 | if (gnet_stats_copy_queue(d, NULL, &qs, qs.qlen) < 0) |
4b549a2e ED |
665 | return -1; |
666 | if (idx < q->flows_cnt) | |
667 | return gnet_stats_copy_app(d, &xstats, sizeof(xstats)); | |
668 | return 0; | |
669 | } | |
670 | ||
671 | static void fq_codel_walk(struct Qdisc *sch, struct qdisc_walker *arg) | |
672 | { | |
673 | struct fq_codel_sched_data *q = qdisc_priv(sch); | |
674 | unsigned int i; | |
675 | ||
676 | if (arg->stop) | |
677 | return; | |
678 | ||
679 | for (i = 0; i < q->flows_cnt; i++) { | |
680 | if (list_empty(&q->flows[i].flowchain) || | |
681 | arg->count < arg->skip) { | |
682 | arg->count++; | |
683 | continue; | |
684 | } | |
685 | if (arg->fn(sch, i + 1, arg) < 0) { | |
686 | arg->stop = 1; | |
687 | break; | |
688 | } | |
689 | arg->count++; | |
690 | } | |
691 | } | |
692 | ||
693 | static const struct Qdisc_class_ops fq_codel_class_ops = { | |
694 | .leaf = fq_codel_leaf, | |
695 | .get = fq_codel_get, | |
696 | .put = fq_codel_put, | |
697 | .tcf_chain = fq_codel_find_tcf, | |
698 | .bind_tcf = fq_codel_bind, | |
699 | .unbind_tcf = fq_codel_put, | |
700 | .dump = fq_codel_dump_class, | |
701 | .dump_stats = fq_codel_dump_class_stats, | |
702 | .walk = fq_codel_walk, | |
703 | }; | |
704 | ||
705 | static struct Qdisc_ops fq_codel_qdisc_ops __read_mostly = { | |
706 | .cl_ops = &fq_codel_class_ops, | |
707 | .id = "fq_codel", | |
708 | .priv_size = sizeof(struct fq_codel_sched_data), | |
709 | .enqueue = fq_codel_enqueue, | |
710 | .dequeue = fq_codel_dequeue, | |
711 | .peek = qdisc_peek_dequeued, | |
c0afd9ce | 712 | .drop = fq_codel_qdisc_drop, |
4b549a2e ED |
713 | .init = fq_codel_init, |
714 | .reset = fq_codel_reset, | |
715 | .destroy = fq_codel_destroy, | |
716 | .change = fq_codel_change, | |
717 | .dump = fq_codel_dump, | |
718 | .dump_stats = fq_codel_dump_stats, | |
719 | .owner = THIS_MODULE, | |
720 | }; | |
721 | ||
722 | static int __init fq_codel_module_init(void) | |
723 | { | |
724 | return register_qdisc(&fq_codel_qdisc_ops); | |
725 | } | |
726 | ||
727 | static void __exit fq_codel_module_exit(void) | |
728 | { | |
729 | unregister_qdisc(&fq_codel_qdisc_ops); | |
730 | } | |
731 | ||
732 | module_init(fq_codel_module_init) | |
733 | module_exit(fq_codel_module_exit) | |
734 | MODULE_AUTHOR("Eric Dumazet"); | |
735 | MODULE_LICENSE("GPL"); |