]>
Commit | Line | Data |
---|---|---|
afe4fd06 ED |
1 | /* |
2 | * net/sched/sch_fq.c Fair Queue Packet Scheduler (per flow pacing) | |
3 | * | |
4 | * Copyright (C) 2013 Eric Dumazet <edumazet@google.com> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | * | |
11 | * Meant to be mostly used for localy generated traffic : | |
12 | * Fast classification depends on skb->sk being set before reaching us. | |
13 | * If not, (router workload), we use rxhash as fallback, with 32 bits wide hash. | |
14 | * All packets belonging to a socket are considered as a 'flow'. | |
15 | * | |
16 | * Flows are dynamically allocated and stored in a hash table of RB trees | |
17 | * They are also part of one Round Robin 'queues' (new or old flows) | |
18 | * | |
19 | * Burst avoidance (aka pacing) capability : | |
20 | * | |
21 | * Transport (eg TCP) can set in sk->sk_pacing_rate a rate, enqueue a | |
22 | * bunch of packets, and this packet scheduler adds delay between | |
23 | * packets to respect rate limitation. | |
24 | * | |
25 | * enqueue() : | |
26 | * - lookup one RB tree (out of 1024 or more) to find the flow. | |
27 | * If non existent flow, create it, add it to the tree. | |
28 | * Add skb to the per flow list of skb (fifo). | |
29 | * - Use a special fifo for high prio packets | |
30 | * | |
31 | * dequeue() : serves flows in Round Robin | |
32 | * Note : When a flow becomes empty, we do not immediately remove it from | |
33 | * rb trees, for performance reasons (its expected to send additional packets, | |
34 | * or SLAB cache will reuse socket for another flow) | |
35 | */ | |
36 | ||
37 | #include <linux/module.h> | |
38 | #include <linux/types.h> | |
39 | #include <linux/kernel.h> | |
40 | #include <linux/jiffies.h> | |
41 | #include <linux/string.h> | |
42 | #include <linux/in.h> | |
43 | #include <linux/errno.h> | |
44 | #include <linux/init.h> | |
45 | #include <linux/skbuff.h> | |
46 | #include <linux/slab.h> | |
47 | #include <linux/rbtree.h> | |
48 | #include <linux/hash.h> | |
08f89b98 | 49 | #include <linux/prefetch.h> |
afe4fd06 ED |
50 | #include <net/netlink.h> |
51 | #include <net/pkt_sched.h> | |
52 | #include <net/sock.h> | |
53 | #include <net/tcp_states.h> | |
54 | ||
55 | /* | |
56 | * Per flow structure, dynamically allocated | |
57 | */ | |
58 | struct fq_flow { | |
59 | struct sk_buff *head; /* list of skbs for this flow : first skb */ | |
60 | union { | |
61 | struct sk_buff *tail; /* last skb in the list */ | |
62 | unsigned long age; /* jiffies when flow was emptied, for gc */ | |
63 | }; | |
64 | struct rb_node fq_node; /* anchor in fq_root[] trees */ | |
65 | struct sock *sk; | |
66 | int qlen; /* number of packets in flow queue */ | |
67 | int credit; | |
68 | u32 socket_hash; /* sk_hash */ | |
69 | struct fq_flow *next; /* next pointer in RR lists, or &detached */ | |
70 | ||
71 | struct rb_node rate_node; /* anchor in q->delayed tree */ | |
72 | u64 time_next_packet; | |
73 | }; | |
74 | ||
75 | struct fq_flow_head { | |
76 | struct fq_flow *first; | |
77 | struct fq_flow *last; | |
78 | }; | |
79 | ||
80 | struct fq_sched_data { | |
81 | struct fq_flow_head new_flows; | |
82 | ||
83 | struct fq_flow_head old_flows; | |
84 | ||
85 | struct rb_root delayed; /* for rate limited flows */ | |
86 | u64 time_next_delayed_flow; | |
87 | ||
88 | struct fq_flow internal; /* for non classified or high prio packets */ | |
89 | u32 quantum; | |
90 | u32 initial_quantum; | |
f52ed899 | 91 | u32 flow_refill_delay; |
afe4fd06 ED |
92 | u32 flow_max_rate; /* optional max rate per flow */ |
93 | u32 flow_plimit; /* max packets per flow */ | |
94 | struct rb_root *fq_root; | |
95 | u8 rate_enable; | |
96 | u8 fq_trees_log; | |
97 | ||
98 | u32 flows; | |
99 | u32 inactive_flows; | |
100 | u32 throttled_flows; | |
101 | ||
102 | u64 stat_gc_flows; | |
103 | u64 stat_internal_packets; | |
104 | u64 stat_tcp_retrans; | |
105 | u64 stat_throttled; | |
106 | u64 stat_flows_plimit; | |
107 | u64 stat_pkts_too_long; | |
108 | u64 stat_allocation_errors; | |
109 | struct qdisc_watchdog watchdog; | |
110 | }; | |
111 | ||
112 | /* special value to mark a detached flow (not on old/new list) */ | |
113 | static struct fq_flow detached, throttled; | |
114 | ||
115 | static void fq_flow_set_detached(struct fq_flow *f) | |
116 | { | |
117 | f->next = &detached; | |
f52ed899 | 118 | f->age = jiffies; |
afe4fd06 ED |
119 | } |
120 | ||
121 | static bool fq_flow_is_detached(const struct fq_flow *f) | |
122 | { | |
123 | return f->next == &detached; | |
124 | } | |
125 | ||
126 | static void fq_flow_set_throttled(struct fq_sched_data *q, struct fq_flow *f) | |
127 | { | |
128 | struct rb_node **p = &q->delayed.rb_node, *parent = NULL; | |
129 | ||
130 | while (*p) { | |
131 | struct fq_flow *aux; | |
132 | ||
133 | parent = *p; | |
134 | aux = container_of(parent, struct fq_flow, rate_node); | |
135 | if (f->time_next_packet >= aux->time_next_packet) | |
136 | p = &parent->rb_right; | |
137 | else | |
138 | p = &parent->rb_left; | |
139 | } | |
140 | rb_link_node(&f->rate_node, parent, p); | |
141 | rb_insert_color(&f->rate_node, &q->delayed); | |
142 | q->throttled_flows++; | |
143 | q->stat_throttled++; | |
144 | ||
145 | f->next = &throttled; | |
146 | if (q->time_next_delayed_flow > f->time_next_packet) | |
147 | q->time_next_delayed_flow = f->time_next_packet; | |
148 | } | |
149 | ||
150 | ||
151 | static struct kmem_cache *fq_flow_cachep __read_mostly; | |
152 | ||
153 | static void fq_flow_add_tail(struct fq_flow_head *head, struct fq_flow *flow) | |
154 | { | |
155 | if (head->first) | |
156 | head->last->next = flow; | |
157 | else | |
158 | head->first = flow; | |
159 | head->last = flow; | |
160 | flow->next = NULL; | |
161 | } | |
162 | ||
163 | /* limit number of collected flows per round */ | |
164 | #define FQ_GC_MAX 8 | |
165 | #define FQ_GC_AGE (3*HZ) | |
166 | ||
167 | static bool fq_gc_candidate(const struct fq_flow *f) | |
168 | { | |
169 | return fq_flow_is_detached(f) && | |
170 | time_after(jiffies, f->age + FQ_GC_AGE); | |
171 | } | |
172 | ||
173 | static void fq_gc(struct fq_sched_data *q, | |
174 | struct rb_root *root, | |
175 | struct sock *sk) | |
176 | { | |
177 | struct fq_flow *f, *tofree[FQ_GC_MAX]; | |
178 | struct rb_node **p, *parent; | |
179 | int fcnt = 0; | |
180 | ||
181 | p = &root->rb_node; | |
182 | parent = NULL; | |
183 | while (*p) { | |
184 | parent = *p; | |
185 | ||
186 | f = container_of(parent, struct fq_flow, fq_node); | |
187 | if (f->sk == sk) | |
188 | break; | |
189 | ||
190 | if (fq_gc_candidate(f)) { | |
191 | tofree[fcnt++] = f; | |
192 | if (fcnt == FQ_GC_MAX) | |
193 | break; | |
194 | } | |
195 | ||
196 | if (f->sk > sk) | |
197 | p = &parent->rb_right; | |
198 | else | |
199 | p = &parent->rb_left; | |
200 | } | |
201 | ||
202 | q->flows -= fcnt; | |
203 | q->inactive_flows -= fcnt; | |
204 | q->stat_gc_flows += fcnt; | |
205 | while (fcnt) { | |
206 | struct fq_flow *f = tofree[--fcnt]; | |
207 | ||
208 | rb_erase(&f->fq_node, root); | |
209 | kmem_cache_free(fq_flow_cachep, f); | |
210 | } | |
211 | } | |
212 | ||
afe4fd06 ED |
213 | static struct fq_flow *fq_classify(struct sk_buff *skb, struct fq_sched_data *q) |
214 | { | |
215 | struct rb_node **p, *parent; | |
216 | struct sock *sk = skb->sk; | |
217 | struct rb_root *root; | |
218 | struct fq_flow *f; | |
afe4fd06 ED |
219 | |
220 | /* warning: no starvation prevention... */ | |
2abc2f07 | 221 | if (unlikely((skb->priority & TC_PRIO_MAX) == TC_PRIO_CONTROL)) |
afe4fd06 ED |
222 | return &q->internal; |
223 | ||
224 | if (unlikely(!sk)) { | |
225 | /* By forcing low order bit to 1, we make sure to not | |
226 | * collide with a local flow (socket pointers are word aligned) | |
227 | */ | |
228 | sk = (struct sock *)(skb_get_rxhash(skb) | 1L); | |
229 | } | |
230 | ||
231 | root = &q->fq_root[hash_32((u32)(long)sk, q->fq_trees_log)]; | |
232 | ||
233 | if (q->flows >= (2U << q->fq_trees_log) && | |
234 | q->inactive_flows > q->flows/2) | |
235 | fq_gc(q, root, sk); | |
236 | ||
237 | p = &root->rb_node; | |
238 | parent = NULL; | |
239 | while (*p) { | |
240 | parent = *p; | |
241 | ||
242 | f = container_of(parent, struct fq_flow, fq_node); | |
243 | if (f->sk == sk) { | |
244 | /* socket might have been reallocated, so check | |
245 | * if its sk_hash is the same. | |
246 | * It not, we need to refill credit with | |
247 | * initial quantum | |
248 | */ | |
249 | if (unlikely(skb->sk && | |
250 | f->socket_hash != sk->sk_hash)) { | |
251 | f->credit = q->initial_quantum; | |
252 | f->socket_hash = sk->sk_hash; | |
fc59d5bd | 253 | f->time_next_packet = 0ULL; |
afe4fd06 ED |
254 | } |
255 | return f; | |
256 | } | |
257 | if (f->sk > sk) | |
258 | p = &parent->rb_right; | |
259 | else | |
260 | p = &parent->rb_left; | |
261 | } | |
262 | ||
263 | f = kmem_cache_zalloc(fq_flow_cachep, GFP_ATOMIC | __GFP_NOWARN); | |
264 | if (unlikely(!f)) { | |
265 | q->stat_allocation_errors++; | |
266 | return &q->internal; | |
267 | } | |
268 | fq_flow_set_detached(f); | |
269 | f->sk = sk; | |
270 | if (skb->sk) | |
271 | f->socket_hash = sk->sk_hash; | |
272 | f->credit = q->initial_quantum; | |
273 | ||
274 | rb_link_node(&f->fq_node, parent, p); | |
275 | rb_insert_color(&f->fq_node, root); | |
276 | ||
277 | q->flows++; | |
278 | q->inactive_flows++; | |
279 | return f; | |
280 | } | |
281 | ||
282 | ||
283 | /* remove one skb from head of flow queue */ | |
8d34ce10 | 284 | static struct sk_buff *fq_dequeue_head(struct Qdisc *sch, struct fq_flow *flow) |
afe4fd06 ED |
285 | { |
286 | struct sk_buff *skb = flow->head; | |
287 | ||
288 | if (skb) { | |
289 | flow->head = skb->next; | |
290 | skb->next = NULL; | |
291 | flow->qlen--; | |
8d34ce10 ED |
292 | sch->qstats.backlog -= qdisc_pkt_len(skb); |
293 | sch->q.qlen--; | |
afe4fd06 ED |
294 | } |
295 | return skb; | |
296 | } | |
297 | ||
298 | /* We might add in the future detection of retransmits | |
299 | * For the time being, just return false | |
300 | */ | |
301 | static bool skb_is_retransmit(struct sk_buff *skb) | |
302 | { | |
303 | return false; | |
304 | } | |
305 | ||
306 | /* add skb to flow queue | |
307 | * flow queue is a linked list, kind of FIFO, except for TCP retransmits | |
308 | * We special case tcp retransmits to be transmitted before other packets. | |
309 | * We rely on fact that TCP retransmits are unlikely, so we do not waste | |
310 | * a separate queue or a pointer. | |
311 | * head-> [retrans pkt 1] | |
312 | * [retrans pkt 2] | |
313 | * [ normal pkt 1] | |
314 | * [ normal pkt 2] | |
315 | * [ normal pkt 3] | |
316 | * tail-> [ normal pkt 4] | |
317 | */ | |
318 | static void flow_queue_add(struct fq_flow *flow, struct sk_buff *skb) | |
319 | { | |
320 | struct sk_buff *prev, *head = flow->head; | |
321 | ||
322 | skb->next = NULL; | |
323 | if (!head) { | |
324 | flow->head = skb; | |
325 | flow->tail = skb; | |
326 | return; | |
327 | } | |
328 | if (likely(!skb_is_retransmit(skb))) { | |
329 | flow->tail->next = skb; | |
330 | flow->tail = skb; | |
331 | return; | |
332 | } | |
333 | ||
334 | /* This skb is a tcp retransmit, | |
335 | * find the last retrans packet in the queue | |
336 | */ | |
337 | prev = NULL; | |
338 | while (skb_is_retransmit(head)) { | |
339 | prev = head; | |
340 | head = head->next; | |
341 | if (!head) | |
342 | break; | |
343 | } | |
344 | if (!prev) { /* no rtx packet in queue, become the new head */ | |
345 | skb->next = flow->head; | |
346 | flow->head = skb; | |
347 | } else { | |
348 | if (prev == flow->tail) | |
349 | flow->tail = skb; | |
350 | else | |
351 | skb->next = prev->next; | |
352 | prev->next = skb; | |
353 | } | |
354 | } | |
355 | ||
356 | static int fq_enqueue(struct sk_buff *skb, struct Qdisc *sch) | |
357 | { | |
358 | struct fq_sched_data *q = qdisc_priv(sch); | |
359 | struct fq_flow *f; | |
360 | ||
361 | if (unlikely(sch->q.qlen >= sch->limit)) | |
362 | return qdisc_drop(skb, sch); | |
363 | ||
364 | f = fq_classify(skb, q); | |
365 | if (unlikely(f->qlen >= q->flow_plimit && f != &q->internal)) { | |
366 | q->stat_flows_plimit++; | |
367 | return qdisc_drop(skb, sch); | |
368 | } | |
369 | ||
370 | f->qlen++; | |
afe4fd06 ED |
371 | if (skb_is_retransmit(skb)) |
372 | q->stat_tcp_retrans++; | |
373 | sch->qstats.backlog += qdisc_pkt_len(skb); | |
374 | if (fq_flow_is_detached(f)) { | |
375 | fq_flow_add_tail(&q->new_flows, f); | |
f52ed899 ED |
376 | if (time_after(jiffies, f->age + q->flow_refill_delay)) |
377 | f->credit = max_t(u32, f->credit, q->quantum); | |
afe4fd06 ED |
378 | q->inactive_flows--; |
379 | qdisc_unthrottled(sch); | |
380 | } | |
f52ed899 ED |
381 | |
382 | /* Note: this overwrites f->age */ | |
383 | flow_queue_add(f, skb); | |
384 | ||
afe4fd06 ED |
385 | if (unlikely(f == &q->internal)) { |
386 | q->stat_internal_packets++; | |
387 | qdisc_unthrottled(sch); | |
388 | } | |
389 | sch->q.qlen++; | |
390 | ||
391 | return NET_XMIT_SUCCESS; | |
392 | } | |
393 | ||
394 | static void fq_check_throttled(struct fq_sched_data *q, u64 now) | |
395 | { | |
396 | struct rb_node *p; | |
397 | ||
398 | if (q->time_next_delayed_flow > now) | |
399 | return; | |
400 | ||
401 | q->time_next_delayed_flow = ~0ULL; | |
402 | while ((p = rb_first(&q->delayed)) != NULL) { | |
403 | struct fq_flow *f = container_of(p, struct fq_flow, rate_node); | |
404 | ||
405 | if (f->time_next_packet > now) { | |
406 | q->time_next_delayed_flow = f->time_next_packet; | |
407 | break; | |
408 | } | |
409 | rb_erase(p, &q->delayed); | |
410 | q->throttled_flows--; | |
411 | fq_flow_add_tail(&q->old_flows, f); | |
412 | } | |
413 | } | |
414 | ||
415 | static struct sk_buff *fq_dequeue(struct Qdisc *sch) | |
416 | { | |
417 | struct fq_sched_data *q = qdisc_priv(sch); | |
418 | u64 now = ktime_to_ns(ktime_get()); | |
419 | struct fq_flow_head *head; | |
420 | struct sk_buff *skb; | |
421 | struct fq_flow *f; | |
0eab5eb7 | 422 | u32 rate; |
afe4fd06 | 423 | |
8d34ce10 | 424 | skb = fq_dequeue_head(sch, &q->internal); |
afe4fd06 ED |
425 | if (skb) |
426 | goto out; | |
427 | fq_check_throttled(q, now); | |
428 | begin: | |
429 | head = &q->new_flows; | |
430 | if (!head->first) { | |
431 | head = &q->old_flows; | |
432 | if (!head->first) { | |
433 | if (q->time_next_delayed_flow != ~0ULL) | |
434 | qdisc_watchdog_schedule_ns(&q->watchdog, | |
435 | q->time_next_delayed_flow); | |
436 | return NULL; | |
437 | } | |
438 | } | |
439 | f = head->first; | |
440 | ||
441 | if (f->credit <= 0) { | |
442 | f->credit += q->quantum; | |
443 | head->first = f->next; | |
444 | fq_flow_add_tail(&q->old_flows, f); | |
445 | goto begin; | |
446 | } | |
447 | ||
448 | if (unlikely(f->head && now < f->time_next_packet)) { | |
449 | head->first = f->next; | |
450 | fq_flow_set_throttled(q, f); | |
451 | goto begin; | |
452 | } | |
453 | ||
8d34ce10 | 454 | skb = fq_dequeue_head(sch, f); |
afe4fd06 ED |
455 | if (!skb) { |
456 | head->first = f->next; | |
457 | /* force a pass through old_flows to prevent starvation */ | |
458 | if ((head == &q->new_flows) && q->old_flows.first) { | |
459 | fq_flow_add_tail(&q->old_flows, f); | |
460 | } else { | |
461 | fq_flow_set_detached(f); | |
afe4fd06 ED |
462 | q->inactive_flows++; |
463 | } | |
464 | goto begin; | |
465 | } | |
08f89b98 | 466 | prefetch(&skb->end); |
afe4fd06 ED |
467 | f->time_next_packet = now; |
468 | f->credit -= qdisc_pkt_len(skb); | |
469 | ||
0eab5eb7 ED |
470 | if (f->credit > 0 || !q->rate_enable) |
471 | goto out; | |
afe4fd06 | 472 | |
7eec4174 ED |
473 | rate = q->flow_max_rate; |
474 | if (skb->sk && skb->sk->sk_state != TCP_TIME_WAIT) | |
475 | rate = min(skb->sk->sk_pacing_rate, rate); | |
afe4fd06 | 476 | |
7eec4174 | 477 | if (rate != ~0U) { |
0eab5eb7 ED |
478 | u32 plen = max(qdisc_pkt_len(skb), q->quantum); |
479 | u64 len = (u64)plen * NSEC_PER_SEC; | |
480 | ||
7eec4174 ED |
481 | if (likely(rate)) |
482 | do_div(len, rate); | |
0eab5eb7 ED |
483 | /* Since socket rate can change later, |
484 | * clamp the delay to 125 ms. | |
485 | * TODO: maybe segment the too big skb, as in commit | |
486 | * e43ac79a4bc ("sch_tbf: segment too big GSO packets") | |
487 | */ | |
488 | if (unlikely(len > 125 * NSEC_PER_MSEC)) { | |
489 | len = 125 * NSEC_PER_MSEC; | |
490 | q->stat_pkts_too_long++; | |
afe4fd06 | 491 | } |
0eab5eb7 ED |
492 | |
493 | f->time_next_packet = now + len; | |
afe4fd06 ED |
494 | } |
495 | out: | |
afe4fd06 | 496 | qdisc_bstats_update(sch, skb); |
afe4fd06 ED |
497 | qdisc_unthrottled(sch); |
498 | return skb; | |
499 | } | |
500 | ||
501 | static void fq_reset(struct Qdisc *sch) | |
502 | { | |
8d34ce10 ED |
503 | struct fq_sched_data *q = qdisc_priv(sch); |
504 | struct rb_root *root; | |
afe4fd06 | 505 | struct sk_buff *skb; |
8d34ce10 ED |
506 | struct rb_node *p; |
507 | struct fq_flow *f; | |
508 | unsigned int idx; | |
afe4fd06 | 509 | |
8d34ce10 | 510 | while ((skb = fq_dequeue_head(sch, &q->internal)) != NULL) |
afe4fd06 | 511 | kfree_skb(skb); |
8d34ce10 ED |
512 | |
513 | if (!q->fq_root) | |
514 | return; | |
515 | ||
516 | for (idx = 0; idx < (1U << q->fq_trees_log); idx++) { | |
517 | root = &q->fq_root[idx]; | |
518 | while ((p = rb_first(root)) != NULL) { | |
519 | f = container_of(p, struct fq_flow, fq_node); | |
520 | rb_erase(p, root); | |
521 | ||
522 | while ((skb = fq_dequeue_head(sch, f)) != NULL) | |
523 | kfree_skb(skb); | |
524 | ||
525 | kmem_cache_free(fq_flow_cachep, f); | |
526 | } | |
527 | } | |
528 | q->new_flows.first = NULL; | |
529 | q->old_flows.first = NULL; | |
530 | q->delayed = RB_ROOT; | |
531 | q->flows = 0; | |
532 | q->inactive_flows = 0; | |
533 | q->throttled_flows = 0; | |
afe4fd06 ED |
534 | } |
535 | ||
536 | static void fq_rehash(struct fq_sched_data *q, | |
537 | struct rb_root *old_array, u32 old_log, | |
538 | struct rb_root *new_array, u32 new_log) | |
539 | { | |
540 | struct rb_node *op, **np, *parent; | |
541 | struct rb_root *oroot, *nroot; | |
542 | struct fq_flow *of, *nf; | |
543 | int fcnt = 0; | |
544 | u32 idx; | |
545 | ||
546 | for (idx = 0; idx < (1U << old_log); idx++) { | |
547 | oroot = &old_array[idx]; | |
548 | while ((op = rb_first(oroot)) != NULL) { | |
549 | rb_erase(op, oroot); | |
550 | of = container_of(op, struct fq_flow, fq_node); | |
551 | if (fq_gc_candidate(of)) { | |
552 | fcnt++; | |
553 | kmem_cache_free(fq_flow_cachep, of); | |
554 | continue; | |
555 | } | |
556 | nroot = &new_array[hash_32((u32)(long)of->sk, new_log)]; | |
557 | ||
558 | np = &nroot->rb_node; | |
559 | parent = NULL; | |
560 | while (*np) { | |
561 | parent = *np; | |
562 | ||
563 | nf = container_of(parent, struct fq_flow, fq_node); | |
564 | BUG_ON(nf->sk == of->sk); | |
565 | ||
566 | if (nf->sk > of->sk) | |
567 | np = &parent->rb_right; | |
568 | else | |
569 | np = &parent->rb_left; | |
570 | } | |
571 | ||
572 | rb_link_node(&of->fq_node, parent, np); | |
573 | rb_insert_color(&of->fq_node, nroot); | |
574 | } | |
575 | } | |
576 | q->flows -= fcnt; | |
577 | q->inactive_flows -= fcnt; | |
578 | q->stat_gc_flows += fcnt; | |
579 | } | |
580 | ||
581 | static int fq_resize(struct fq_sched_data *q, u32 log) | |
582 | { | |
583 | struct rb_root *array; | |
584 | u32 idx; | |
585 | ||
586 | if (q->fq_root && log == q->fq_trees_log) | |
587 | return 0; | |
588 | ||
589 | array = kmalloc(sizeof(struct rb_root) << log, GFP_KERNEL); | |
590 | if (!array) | |
591 | return -ENOMEM; | |
592 | ||
593 | for (idx = 0; idx < (1U << log); idx++) | |
594 | array[idx] = RB_ROOT; | |
595 | ||
596 | if (q->fq_root) { | |
597 | fq_rehash(q, q->fq_root, q->fq_trees_log, array, log); | |
598 | kfree(q->fq_root); | |
599 | } | |
600 | q->fq_root = array; | |
601 | q->fq_trees_log = log; | |
602 | ||
603 | return 0; | |
604 | } | |
605 | ||
606 | static const struct nla_policy fq_policy[TCA_FQ_MAX + 1] = { | |
607 | [TCA_FQ_PLIMIT] = { .type = NLA_U32 }, | |
608 | [TCA_FQ_FLOW_PLIMIT] = { .type = NLA_U32 }, | |
609 | [TCA_FQ_QUANTUM] = { .type = NLA_U32 }, | |
610 | [TCA_FQ_INITIAL_QUANTUM] = { .type = NLA_U32 }, | |
611 | [TCA_FQ_RATE_ENABLE] = { .type = NLA_U32 }, | |
612 | [TCA_FQ_FLOW_DEFAULT_RATE] = { .type = NLA_U32 }, | |
613 | [TCA_FQ_FLOW_MAX_RATE] = { .type = NLA_U32 }, | |
614 | [TCA_FQ_BUCKETS_LOG] = { .type = NLA_U32 }, | |
f52ed899 | 615 | [TCA_FQ_FLOW_REFILL_DELAY] = { .type = NLA_U32 }, |
afe4fd06 ED |
616 | }; |
617 | ||
618 | static int fq_change(struct Qdisc *sch, struct nlattr *opt) | |
619 | { | |
620 | struct fq_sched_data *q = qdisc_priv(sch); | |
621 | struct nlattr *tb[TCA_FQ_MAX + 1]; | |
622 | int err, drop_count = 0; | |
623 | u32 fq_log; | |
624 | ||
625 | if (!opt) | |
626 | return -EINVAL; | |
627 | ||
628 | err = nla_parse_nested(tb, TCA_FQ_MAX, opt, fq_policy); | |
629 | if (err < 0) | |
630 | return err; | |
631 | ||
632 | sch_tree_lock(sch); | |
633 | ||
634 | fq_log = q->fq_trees_log; | |
635 | ||
636 | if (tb[TCA_FQ_BUCKETS_LOG]) { | |
637 | u32 nval = nla_get_u32(tb[TCA_FQ_BUCKETS_LOG]); | |
638 | ||
639 | if (nval >= 1 && nval <= ilog2(256*1024)) | |
640 | fq_log = nval; | |
641 | else | |
642 | err = -EINVAL; | |
643 | } | |
644 | if (tb[TCA_FQ_PLIMIT]) | |
645 | sch->limit = nla_get_u32(tb[TCA_FQ_PLIMIT]); | |
646 | ||
647 | if (tb[TCA_FQ_FLOW_PLIMIT]) | |
648 | q->flow_plimit = nla_get_u32(tb[TCA_FQ_FLOW_PLIMIT]); | |
649 | ||
650 | if (tb[TCA_FQ_QUANTUM]) | |
651 | q->quantum = nla_get_u32(tb[TCA_FQ_QUANTUM]); | |
652 | ||
653 | if (tb[TCA_FQ_INITIAL_QUANTUM]) | |
ede869cd | 654 | q->initial_quantum = nla_get_u32(tb[TCA_FQ_INITIAL_QUANTUM]); |
afe4fd06 ED |
655 | |
656 | if (tb[TCA_FQ_FLOW_DEFAULT_RATE]) | |
65c5189a ED |
657 | pr_warn_ratelimited("sch_fq: defrate %u ignored.\n", |
658 | nla_get_u32(tb[TCA_FQ_FLOW_DEFAULT_RATE])); | |
afe4fd06 ED |
659 | |
660 | if (tb[TCA_FQ_FLOW_MAX_RATE]) | |
661 | q->flow_max_rate = nla_get_u32(tb[TCA_FQ_FLOW_MAX_RATE]); | |
662 | ||
663 | if (tb[TCA_FQ_RATE_ENABLE]) { | |
664 | u32 enable = nla_get_u32(tb[TCA_FQ_RATE_ENABLE]); | |
665 | ||
666 | if (enable <= 1) | |
667 | q->rate_enable = enable; | |
668 | else | |
669 | err = -EINVAL; | |
670 | } | |
671 | ||
f52ed899 ED |
672 | if (tb[TCA_FQ_FLOW_REFILL_DELAY]) { |
673 | u32 usecs_delay = nla_get_u32(tb[TCA_FQ_FLOW_REFILL_DELAY]) ; | |
674 | ||
675 | q->flow_refill_delay = usecs_to_jiffies(usecs_delay); | |
676 | } | |
677 | ||
afe4fd06 ED |
678 | if (!err) |
679 | err = fq_resize(q, fq_log); | |
680 | ||
681 | while (sch->q.qlen > sch->limit) { | |
682 | struct sk_buff *skb = fq_dequeue(sch); | |
683 | ||
8d34ce10 ED |
684 | if (!skb) |
685 | break; | |
afe4fd06 ED |
686 | kfree_skb(skb); |
687 | drop_count++; | |
688 | } | |
689 | qdisc_tree_decrease_qlen(sch, drop_count); | |
690 | ||
691 | sch_tree_unlock(sch); | |
692 | return err; | |
693 | } | |
694 | ||
695 | static void fq_destroy(struct Qdisc *sch) | |
696 | { | |
697 | struct fq_sched_data *q = qdisc_priv(sch); | |
afe4fd06 | 698 | |
8d34ce10 ED |
699 | fq_reset(sch); |
700 | kfree(q->fq_root); | |
afe4fd06 ED |
701 | qdisc_watchdog_cancel(&q->watchdog); |
702 | } | |
703 | ||
704 | static int fq_init(struct Qdisc *sch, struct nlattr *opt) | |
705 | { | |
706 | struct fq_sched_data *q = qdisc_priv(sch); | |
707 | int err; | |
708 | ||
709 | sch->limit = 10000; | |
710 | q->flow_plimit = 100; | |
711 | q->quantum = 2 * psched_mtu(qdisc_dev(sch)); | |
712 | q->initial_quantum = 10 * psched_mtu(qdisc_dev(sch)); | |
f52ed899 | 713 | q->flow_refill_delay = msecs_to_jiffies(40); |
afe4fd06 ED |
714 | q->flow_max_rate = ~0U; |
715 | q->rate_enable = 1; | |
716 | q->new_flows.first = NULL; | |
717 | q->old_flows.first = NULL; | |
718 | q->delayed = RB_ROOT; | |
719 | q->fq_root = NULL; | |
720 | q->fq_trees_log = ilog2(1024); | |
721 | qdisc_watchdog_init(&q->watchdog, sch); | |
722 | ||
723 | if (opt) | |
724 | err = fq_change(sch, opt); | |
725 | else | |
726 | err = fq_resize(q, q->fq_trees_log); | |
727 | ||
728 | return err; | |
729 | } | |
730 | ||
731 | static int fq_dump(struct Qdisc *sch, struct sk_buff *skb) | |
732 | { | |
733 | struct fq_sched_data *q = qdisc_priv(sch); | |
734 | struct nlattr *opts; | |
735 | ||
736 | opts = nla_nest_start(skb, TCA_OPTIONS); | |
737 | if (opts == NULL) | |
738 | goto nla_put_failure; | |
739 | ||
65c5189a ED |
740 | /* TCA_FQ_FLOW_DEFAULT_RATE is not used anymore */ |
741 | ||
afe4fd06 ED |
742 | if (nla_put_u32(skb, TCA_FQ_PLIMIT, sch->limit) || |
743 | nla_put_u32(skb, TCA_FQ_FLOW_PLIMIT, q->flow_plimit) || | |
744 | nla_put_u32(skb, TCA_FQ_QUANTUM, q->quantum) || | |
745 | nla_put_u32(skb, TCA_FQ_INITIAL_QUANTUM, q->initial_quantum) || | |
746 | nla_put_u32(skb, TCA_FQ_RATE_ENABLE, q->rate_enable) || | |
afe4fd06 | 747 | nla_put_u32(skb, TCA_FQ_FLOW_MAX_RATE, q->flow_max_rate) || |
f52ed899 ED |
748 | nla_put_u32(skb, TCA_FQ_FLOW_REFILL_DELAY, |
749 | jiffies_to_usecs(q->flow_refill_delay)) || | |
afe4fd06 ED |
750 | nla_put_u32(skb, TCA_FQ_BUCKETS_LOG, q->fq_trees_log)) |
751 | goto nla_put_failure; | |
752 | ||
753 | nla_nest_end(skb, opts); | |
754 | return skb->len; | |
755 | ||
756 | nla_put_failure: | |
757 | return -1; | |
758 | } | |
759 | ||
760 | static int fq_dump_stats(struct Qdisc *sch, struct gnet_dump *d) | |
761 | { | |
762 | struct fq_sched_data *q = qdisc_priv(sch); | |
763 | u64 now = ktime_to_ns(ktime_get()); | |
764 | struct tc_fq_qd_stats st = { | |
765 | .gc_flows = q->stat_gc_flows, | |
766 | .highprio_packets = q->stat_internal_packets, | |
767 | .tcp_retrans = q->stat_tcp_retrans, | |
768 | .throttled = q->stat_throttled, | |
769 | .flows_plimit = q->stat_flows_plimit, | |
770 | .pkts_too_long = q->stat_pkts_too_long, | |
771 | .allocation_errors = q->stat_allocation_errors, | |
772 | .flows = q->flows, | |
773 | .inactive_flows = q->inactive_flows, | |
774 | .throttled_flows = q->throttled_flows, | |
775 | .time_next_delayed_flow = q->time_next_delayed_flow - now, | |
776 | }; | |
777 | ||
778 | return gnet_stats_copy_app(d, &st, sizeof(st)); | |
779 | } | |
780 | ||
781 | static struct Qdisc_ops fq_qdisc_ops __read_mostly = { | |
782 | .id = "fq", | |
783 | .priv_size = sizeof(struct fq_sched_data), | |
784 | ||
785 | .enqueue = fq_enqueue, | |
786 | .dequeue = fq_dequeue, | |
787 | .peek = qdisc_peek_dequeued, | |
788 | .init = fq_init, | |
789 | .reset = fq_reset, | |
790 | .destroy = fq_destroy, | |
791 | .change = fq_change, | |
792 | .dump = fq_dump, | |
793 | .dump_stats = fq_dump_stats, | |
794 | .owner = THIS_MODULE, | |
795 | }; | |
796 | ||
797 | static int __init fq_module_init(void) | |
798 | { | |
799 | int ret; | |
800 | ||
801 | fq_flow_cachep = kmem_cache_create("fq_flow_cache", | |
802 | sizeof(struct fq_flow), | |
803 | 0, 0, NULL); | |
804 | if (!fq_flow_cachep) | |
805 | return -ENOMEM; | |
806 | ||
807 | ret = register_qdisc(&fq_qdisc_ops); | |
808 | if (ret) | |
809 | kmem_cache_destroy(fq_flow_cachep); | |
810 | return ret; | |
811 | } | |
812 | ||
813 | static void __exit fq_module_exit(void) | |
814 | { | |
815 | unregister_qdisc(&fq_qdisc_ops); | |
816 | kmem_cache_destroy(fq_flow_cachep); | |
817 | } | |
818 | ||
819 | module_init(fq_module_init) | |
820 | module_exit(fq_module_exit) | |
821 | MODULE_AUTHOR("Eric Dumazet"); | |
822 | MODULE_LICENSE("GPL"); |