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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> |
c3bd8549 | 50 | #include <linux/vmalloc.h> |
afe4fd06 ED |
51 | #include <net/netlink.h> |
52 | #include <net/pkt_sched.h> | |
53 | #include <net/sock.h> | |
54 | #include <net/tcp_states.h> | |
55 | ||
56 | /* | |
57 | * Per flow structure, dynamically allocated | |
58 | */ | |
59 | struct fq_flow { | |
60 | struct sk_buff *head; /* list of skbs for this flow : first skb */ | |
61 | union { | |
62 | struct sk_buff *tail; /* last skb in the list */ | |
63 | unsigned long age; /* jiffies when flow was emptied, for gc */ | |
64 | }; | |
65 | struct rb_node fq_node; /* anchor in fq_root[] trees */ | |
66 | struct sock *sk; | |
67 | int qlen; /* number of packets in flow queue */ | |
68 | int credit; | |
69 | u32 socket_hash; /* sk_hash */ | |
70 | struct fq_flow *next; /* next pointer in RR lists, or &detached */ | |
71 | ||
72 | struct rb_node rate_node; /* anchor in q->delayed tree */ | |
73 | u64 time_next_packet; | |
74 | }; | |
75 | ||
76 | struct fq_flow_head { | |
77 | struct fq_flow *first; | |
78 | struct fq_flow *last; | |
79 | }; | |
80 | ||
81 | struct fq_sched_data { | |
82 | struct fq_flow_head new_flows; | |
83 | ||
84 | struct fq_flow_head old_flows; | |
85 | ||
86 | struct rb_root delayed; /* for rate limited flows */ | |
87 | u64 time_next_delayed_flow; | |
88 | ||
89 | struct fq_flow internal; /* for non classified or high prio packets */ | |
90 | u32 quantum; | |
91 | u32 initial_quantum; | |
f52ed899 | 92 | u32 flow_refill_delay; |
afe4fd06 ED |
93 | u32 flow_max_rate; /* optional max rate per flow */ |
94 | u32 flow_plimit; /* max packets per flow */ | |
95 | struct rb_root *fq_root; | |
96 | u8 rate_enable; | |
97 | u8 fq_trees_log; | |
98 | ||
99 | u32 flows; | |
100 | u32 inactive_flows; | |
101 | u32 throttled_flows; | |
102 | ||
103 | u64 stat_gc_flows; | |
104 | u64 stat_internal_packets; | |
105 | u64 stat_tcp_retrans; | |
106 | u64 stat_throttled; | |
107 | u64 stat_flows_plimit; | |
108 | u64 stat_pkts_too_long; | |
109 | u64 stat_allocation_errors; | |
110 | struct qdisc_watchdog watchdog; | |
111 | }; | |
112 | ||
113 | /* special value to mark a detached flow (not on old/new list) */ | |
114 | static struct fq_flow detached, throttled; | |
115 | ||
116 | static void fq_flow_set_detached(struct fq_flow *f) | |
117 | { | |
118 | f->next = &detached; | |
f52ed899 | 119 | f->age = jiffies; |
afe4fd06 ED |
120 | } |
121 | ||
122 | static bool fq_flow_is_detached(const struct fq_flow *f) | |
123 | { | |
124 | return f->next == &detached; | |
125 | } | |
126 | ||
127 | static void fq_flow_set_throttled(struct fq_sched_data *q, struct fq_flow *f) | |
128 | { | |
129 | struct rb_node **p = &q->delayed.rb_node, *parent = NULL; | |
130 | ||
131 | while (*p) { | |
132 | struct fq_flow *aux; | |
133 | ||
134 | parent = *p; | |
135 | aux = container_of(parent, struct fq_flow, rate_node); | |
136 | if (f->time_next_packet >= aux->time_next_packet) | |
137 | p = &parent->rb_right; | |
138 | else | |
139 | p = &parent->rb_left; | |
140 | } | |
141 | rb_link_node(&f->rate_node, parent, p); | |
142 | rb_insert_color(&f->rate_node, &q->delayed); | |
143 | q->throttled_flows++; | |
144 | q->stat_throttled++; | |
145 | ||
146 | f->next = &throttled; | |
147 | if (q->time_next_delayed_flow > f->time_next_packet) | |
148 | q->time_next_delayed_flow = f->time_next_packet; | |
149 | } | |
150 | ||
151 | ||
152 | static struct kmem_cache *fq_flow_cachep __read_mostly; | |
153 | ||
154 | static void fq_flow_add_tail(struct fq_flow_head *head, struct fq_flow *flow) | |
155 | { | |
156 | if (head->first) | |
157 | head->last->next = flow; | |
158 | else | |
159 | head->first = flow; | |
160 | head->last = flow; | |
161 | flow->next = NULL; | |
162 | } | |
163 | ||
164 | /* limit number of collected flows per round */ | |
165 | #define FQ_GC_MAX 8 | |
166 | #define FQ_GC_AGE (3*HZ) | |
167 | ||
168 | static bool fq_gc_candidate(const struct fq_flow *f) | |
169 | { | |
170 | return fq_flow_is_detached(f) && | |
171 | time_after(jiffies, f->age + FQ_GC_AGE); | |
172 | } | |
173 | ||
174 | static void fq_gc(struct fq_sched_data *q, | |
175 | struct rb_root *root, | |
176 | struct sock *sk) | |
177 | { | |
178 | struct fq_flow *f, *tofree[FQ_GC_MAX]; | |
179 | struct rb_node **p, *parent; | |
180 | int fcnt = 0; | |
181 | ||
182 | p = &root->rb_node; | |
183 | parent = NULL; | |
184 | while (*p) { | |
185 | parent = *p; | |
186 | ||
187 | f = container_of(parent, struct fq_flow, fq_node); | |
188 | if (f->sk == sk) | |
189 | break; | |
190 | ||
191 | if (fq_gc_candidate(f)) { | |
192 | tofree[fcnt++] = f; | |
193 | if (fcnt == FQ_GC_MAX) | |
194 | break; | |
195 | } | |
196 | ||
197 | if (f->sk > sk) | |
198 | p = &parent->rb_right; | |
199 | else | |
200 | p = &parent->rb_left; | |
201 | } | |
202 | ||
203 | q->flows -= fcnt; | |
204 | q->inactive_flows -= fcnt; | |
205 | q->stat_gc_flows += fcnt; | |
206 | while (fcnt) { | |
207 | struct fq_flow *f = tofree[--fcnt]; | |
208 | ||
209 | rb_erase(&f->fq_node, root); | |
210 | kmem_cache_free(fq_flow_cachep, f); | |
211 | } | |
212 | } | |
213 | ||
afe4fd06 ED |
214 | static struct fq_flow *fq_classify(struct sk_buff *skb, struct fq_sched_data *q) |
215 | { | |
216 | struct rb_node **p, *parent; | |
217 | struct sock *sk = skb->sk; | |
218 | struct rb_root *root; | |
219 | struct fq_flow *f; | |
afe4fd06 ED |
220 | |
221 | /* warning: no starvation prevention... */ | |
2abc2f07 | 222 | if (unlikely((skb->priority & TC_PRIO_MAX) == TC_PRIO_CONTROL)) |
afe4fd06 ED |
223 | return &q->internal; |
224 | ||
225 | if (unlikely(!sk)) { | |
226 | /* By forcing low order bit to 1, we make sure to not | |
227 | * collide with a local flow (socket pointers are word aligned) | |
228 | */ | |
3958afa1 | 229 | sk = (struct sock *)(skb_get_hash(skb) | 1L); |
afe4fd06 ED |
230 | } |
231 | ||
232 | root = &q->fq_root[hash_32((u32)(long)sk, q->fq_trees_log)]; | |
233 | ||
234 | if (q->flows >= (2U << q->fq_trees_log) && | |
235 | q->inactive_flows > q->flows/2) | |
236 | fq_gc(q, root, sk); | |
237 | ||
238 | p = &root->rb_node; | |
239 | parent = NULL; | |
240 | while (*p) { | |
241 | parent = *p; | |
242 | ||
243 | f = container_of(parent, struct fq_flow, fq_node); | |
244 | if (f->sk == sk) { | |
245 | /* socket might have been reallocated, so check | |
246 | * if its sk_hash is the same. | |
247 | * It not, we need to refill credit with | |
248 | * initial quantum | |
249 | */ | |
250 | if (unlikely(skb->sk && | |
251 | f->socket_hash != sk->sk_hash)) { | |
252 | f->credit = q->initial_quantum; | |
253 | f->socket_hash = sk->sk_hash; | |
fc59d5bd | 254 | f->time_next_packet = 0ULL; |
afe4fd06 ED |
255 | } |
256 | return f; | |
257 | } | |
258 | if (f->sk > sk) | |
259 | p = &parent->rb_right; | |
260 | else | |
261 | p = &parent->rb_left; | |
262 | } | |
263 | ||
264 | f = kmem_cache_zalloc(fq_flow_cachep, GFP_ATOMIC | __GFP_NOWARN); | |
265 | if (unlikely(!f)) { | |
266 | q->stat_allocation_errors++; | |
267 | return &q->internal; | |
268 | } | |
269 | fq_flow_set_detached(f); | |
270 | f->sk = sk; | |
271 | if (skb->sk) | |
272 | f->socket_hash = sk->sk_hash; | |
273 | f->credit = q->initial_quantum; | |
274 | ||
275 | rb_link_node(&f->fq_node, parent, p); | |
276 | rb_insert_color(&f->fq_node, root); | |
277 | ||
278 | q->flows++; | |
279 | q->inactive_flows++; | |
280 | return f; | |
281 | } | |
282 | ||
283 | ||
284 | /* remove one skb from head of flow queue */ | |
8d34ce10 | 285 | static struct sk_buff *fq_dequeue_head(struct Qdisc *sch, struct fq_flow *flow) |
afe4fd06 ED |
286 | { |
287 | struct sk_buff *skb = flow->head; | |
288 | ||
289 | if (skb) { | |
290 | flow->head = skb->next; | |
291 | skb->next = NULL; | |
292 | flow->qlen--; | |
8d34ce10 ED |
293 | sch->qstats.backlog -= qdisc_pkt_len(skb); |
294 | sch->q.qlen--; | |
afe4fd06 ED |
295 | } |
296 | return skb; | |
297 | } | |
298 | ||
299 | /* We might add in the future detection of retransmits | |
300 | * For the time being, just return false | |
301 | */ | |
302 | static bool skb_is_retransmit(struct sk_buff *skb) | |
303 | { | |
304 | return false; | |
305 | } | |
306 | ||
307 | /* add skb to flow queue | |
308 | * flow queue is a linked list, kind of FIFO, except for TCP retransmits | |
309 | * We special case tcp retransmits to be transmitted before other packets. | |
310 | * We rely on fact that TCP retransmits are unlikely, so we do not waste | |
311 | * a separate queue or a pointer. | |
312 | * head-> [retrans pkt 1] | |
313 | * [retrans pkt 2] | |
314 | * [ normal pkt 1] | |
315 | * [ normal pkt 2] | |
316 | * [ normal pkt 3] | |
317 | * tail-> [ normal pkt 4] | |
318 | */ | |
319 | static void flow_queue_add(struct fq_flow *flow, struct sk_buff *skb) | |
320 | { | |
321 | struct sk_buff *prev, *head = flow->head; | |
322 | ||
323 | skb->next = NULL; | |
324 | if (!head) { | |
325 | flow->head = skb; | |
326 | flow->tail = skb; | |
327 | return; | |
328 | } | |
329 | if (likely(!skb_is_retransmit(skb))) { | |
330 | flow->tail->next = skb; | |
331 | flow->tail = skb; | |
332 | return; | |
333 | } | |
334 | ||
335 | /* This skb is a tcp retransmit, | |
336 | * find the last retrans packet in the queue | |
337 | */ | |
338 | prev = NULL; | |
339 | while (skb_is_retransmit(head)) { | |
340 | prev = head; | |
341 | head = head->next; | |
342 | if (!head) | |
343 | break; | |
344 | } | |
345 | if (!prev) { /* no rtx packet in queue, become the new head */ | |
346 | skb->next = flow->head; | |
347 | flow->head = skb; | |
348 | } else { | |
349 | if (prev == flow->tail) | |
350 | flow->tail = skb; | |
351 | else | |
352 | skb->next = prev->next; | |
353 | prev->next = skb; | |
354 | } | |
355 | } | |
356 | ||
357 | static int fq_enqueue(struct sk_buff *skb, struct Qdisc *sch) | |
358 | { | |
359 | struct fq_sched_data *q = qdisc_priv(sch); | |
360 | struct fq_flow *f; | |
361 | ||
362 | if (unlikely(sch->q.qlen >= sch->limit)) | |
363 | return qdisc_drop(skb, sch); | |
364 | ||
365 | f = fq_classify(skb, q); | |
366 | if (unlikely(f->qlen >= q->flow_plimit && f != &q->internal)) { | |
367 | q->stat_flows_plimit++; | |
368 | return qdisc_drop(skb, sch); | |
369 | } | |
370 | ||
371 | f->qlen++; | |
afe4fd06 ED |
372 | if (skb_is_retransmit(skb)) |
373 | q->stat_tcp_retrans++; | |
374 | sch->qstats.backlog += qdisc_pkt_len(skb); | |
375 | if (fq_flow_is_detached(f)) { | |
376 | fq_flow_add_tail(&q->new_flows, f); | |
f52ed899 ED |
377 | if (time_after(jiffies, f->age + q->flow_refill_delay)) |
378 | f->credit = max_t(u32, f->credit, q->quantum); | |
afe4fd06 ED |
379 | q->inactive_flows--; |
380 | qdisc_unthrottled(sch); | |
381 | } | |
f52ed899 ED |
382 | |
383 | /* Note: this overwrites f->age */ | |
384 | flow_queue_add(f, skb); | |
385 | ||
afe4fd06 ED |
386 | if (unlikely(f == &q->internal)) { |
387 | q->stat_internal_packets++; | |
388 | qdisc_unthrottled(sch); | |
389 | } | |
390 | sch->q.qlen++; | |
391 | ||
392 | return NET_XMIT_SUCCESS; | |
393 | } | |
394 | ||
395 | static void fq_check_throttled(struct fq_sched_data *q, u64 now) | |
396 | { | |
397 | struct rb_node *p; | |
398 | ||
399 | if (q->time_next_delayed_flow > now) | |
400 | return; | |
401 | ||
402 | q->time_next_delayed_flow = ~0ULL; | |
403 | while ((p = rb_first(&q->delayed)) != NULL) { | |
404 | struct fq_flow *f = container_of(p, struct fq_flow, rate_node); | |
405 | ||
406 | if (f->time_next_packet > now) { | |
407 | q->time_next_delayed_flow = f->time_next_packet; | |
408 | break; | |
409 | } | |
410 | rb_erase(p, &q->delayed); | |
411 | q->throttled_flows--; | |
412 | fq_flow_add_tail(&q->old_flows, f); | |
413 | } | |
414 | } | |
415 | ||
416 | static struct sk_buff *fq_dequeue(struct Qdisc *sch) | |
417 | { | |
418 | struct fq_sched_data *q = qdisc_priv(sch); | |
419 | u64 now = ktime_to_ns(ktime_get()); | |
420 | struct fq_flow_head *head; | |
421 | struct sk_buff *skb; | |
422 | struct fq_flow *f; | |
0eab5eb7 | 423 | u32 rate; |
afe4fd06 | 424 | |
8d34ce10 | 425 | skb = fq_dequeue_head(sch, &q->internal); |
afe4fd06 ED |
426 | if (skb) |
427 | goto out; | |
428 | fq_check_throttled(q, now); | |
429 | begin: | |
430 | head = &q->new_flows; | |
431 | if (!head->first) { | |
432 | head = &q->old_flows; | |
433 | if (!head->first) { | |
434 | if (q->time_next_delayed_flow != ~0ULL) | |
435 | qdisc_watchdog_schedule_ns(&q->watchdog, | |
436 | q->time_next_delayed_flow); | |
437 | return NULL; | |
438 | } | |
439 | } | |
440 | f = head->first; | |
441 | ||
442 | if (f->credit <= 0) { | |
443 | f->credit += q->quantum; | |
444 | head->first = f->next; | |
445 | fq_flow_add_tail(&q->old_flows, f); | |
446 | goto begin; | |
447 | } | |
448 | ||
449 | if (unlikely(f->head && now < f->time_next_packet)) { | |
450 | head->first = f->next; | |
451 | fq_flow_set_throttled(q, f); | |
452 | goto begin; | |
453 | } | |
454 | ||
8d34ce10 | 455 | skb = fq_dequeue_head(sch, f); |
afe4fd06 ED |
456 | if (!skb) { |
457 | head->first = f->next; | |
458 | /* force a pass through old_flows to prevent starvation */ | |
459 | if ((head == &q->new_flows) && q->old_flows.first) { | |
460 | fq_flow_add_tail(&q->old_flows, f); | |
461 | } else { | |
462 | fq_flow_set_detached(f); | |
afe4fd06 ED |
463 | q->inactive_flows++; |
464 | } | |
465 | goto begin; | |
466 | } | |
08f89b98 | 467 | prefetch(&skb->end); |
afe4fd06 ED |
468 | f->time_next_packet = now; |
469 | f->credit -= qdisc_pkt_len(skb); | |
470 | ||
0eab5eb7 ED |
471 | if (f->credit > 0 || !q->rate_enable) |
472 | goto out; | |
afe4fd06 | 473 | |
7eec4174 ED |
474 | rate = q->flow_max_rate; |
475 | if (skb->sk && skb->sk->sk_state != TCP_TIME_WAIT) | |
476 | rate = min(skb->sk->sk_pacing_rate, rate); | |
afe4fd06 | 477 | |
7eec4174 | 478 | if (rate != ~0U) { |
0eab5eb7 ED |
479 | u32 plen = max(qdisc_pkt_len(skb), q->quantum); |
480 | u64 len = (u64)plen * NSEC_PER_SEC; | |
481 | ||
7eec4174 ED |
482 | if (likely(rate)) |
483 | do_div(len, rate); | |
0eab5eb7 ED |
484 | /* Since socket rate can change later, |
485 | * clamp the delay to 125 ms. | |
486 | * TODO: maybe segment the too big skb, as in commit | |
487 | * e43ac79a4bc ("sch_tbf: segment too big GSO packets") | |
488 | */ | |
489 | if (unlikely(len > 125 * NSEC_PER_MSEC)) { | |
490 | len = 125 * NSEC_PER_MSEC; | |
491 | q->stat_pkts_too_long++; | |
afe4fd06 | 492 | } |
0eab5eb7 ED |
493 | |
494 | f->time_next_packet = now + len; | |
afe4fd06 ED |
495 | } |
496 | out: | |
afe4fd06 | 497 | qdisc_bstats_update(sch, skb); |
afe4fd06 ED |
498 | qdisc_unthrottled(sch); |
499 | return skb; | |
500 | } | |
501 | ||
502 | static void fq_reset(struct Qdisc *sch) | |
503 | { | |
8d34ce10 ED |
504 | struct fq_sched_data *q = qdisc_priv(sch); |
505 | struct rb_root *root; | |
afe4fd06 | 506 | struct sk_buff *skb; |
8d34ce10 ED |
507 | struct rb_node *p; |
508 | struct fq_flow *f; | |
509 | unsigned int idx; | |
afe4fd06 | 510 | |
8d34ce10 | 511 | while ((skb = fq_dequeue_head(sch, &q->internal)) != NULL) |
afe4fd06 | 512 | kfree_skb(skb); |
8d34ce10 ED |
513 | |
514 | if (!q->fq_root) | |
515 | return; | |
516 | ||
517 | for (idx = 0; idx < (1U << q->fq_trees_log); idx++) { | |
518 | root = &q->fq_root[idx]; | |
519 | while ((p = rb_first(root)) != NULL) { | |
520 | f = container_of(p, struct fq_flow, fq_node); | |
521 | rb_erase(p, root); | |
522 | ||
523 | while ((skb = fq_dequeue_head(sch, f)) != NULL) | |
524 | kfree_skb(skb); | |
525 | ||
526 | kmem_cache_free(fq_flow_cachep, f); | |
527 | } | |
528 | } | |
529 | q->new_flows.first = NULL; | |
530 | q->old_flows.first = NULL; | |
531 | q->delayed = RB_ROOT; | |
532 | q->flows = 0; | |
533 | q->inactive_flows = 0; | |
534 | q->throttled_flows = 0; | |
afe4fd06 ED |
535 | } |
536 | ||
537 | static void fq_rehash(struct fq_sched_data *q, | |
538 | struct rb_root *old_array, u32 old_log, | |
539 | struct rb_root *new_array, u32 new_log) | |
540 | { | |
541 | struct rb_node *op, **np, *parent; | |
542 | struct rb_root *oroot, *nroot; | |
543 | struct fq_flow *of, *nf; | |
544 | int fcnt = 0; | |
545 | u32 idx; | |
546 | ||
547 | for (idx = 0; idx < (1U << old_log); idx++) { | |
548 | oroot = &old_array[idx]; | |
549 | while ((op = rb_first(oroot)) != NULL) { | |
550 | rb_erase(op, oroot); | |
551 | of = container_of(op, struct fq_flow, fq_node); | |
552 | if (fq_gc_candidate(of)) { | |
553 | fcnt++; | |
554 | kmem_cache_free(fq_flow_cachep, of); | |
555 | continue; | |
556 | } | |
557 | nroot = &new_array[hash_32((u32)(long)of->sk, new_log)]; | |
558 | ||
559 | np = &nroot->rb_node; | |
560 | parent = NULL; | |
561 | while (*np) { | |
562 | parent = *np; | |
563 | ||
564 | nf = container_of(parent, struct fq_flow, fq_node); | |
565 | BUG_ON(nf->sk == of->sk); | |
566 | ||
567 | if (nf->sk > of->sk) | |
568 | np = &parent->rb_right; | |
569 | else | |
570 | np = &parent->rb_left; | |
571 | } | |
572 | ||
573 | rb_link_node(&of->fq_node, parent, np); | |
574 | rb_insert_color(&of->fq_node, nroot); | |
575 | } | |
576 | } | |
577 | q->flows -= fcnt; | |
578 | q->inactive_flows -= fcnt; | |
579 | q->stat_gc_flows += fcnt; | |
580 | } | |
581 | ||
c3bd8549 | 582 | static void *fq_alloc_node(size_t sz, int node) |
afe4fd06 | 583 | { |
c3bd8549 ED |
584 | void *ptr; |
585 | ||
586 | ptr = kmalloc_node(sz, GFP_KERNEL | __GFP_REPEAT | __GFP_NOWARN, node); | |
587 | if (!ptr) | |
588 | ptr = vmalloc_node(sz, node); | |
589 | return ptr; | |
590 | } | |
591 | ||
592 | static void fq_free(void *addr) | |
593 | { | |
594 | if (addr && is_vmalloc_addr(addr)) | |
595 | vfree(addr); | |
596 | else | |
597 | kfree(addr); | |
598 | } | |
599 | ||
600 | static int fq_resize(struct Qdisc *sch, u32 log) | |
601 | { | |
602 | struct fq_sched_data *q = qdisc_priv(sch); | |
afe4fd06 | 603 | struct rb_root *array; |
2818fa0f | 604 | void *old_fq_root; |
afe4fd06 ED |
605 | u32 idx; |
606 | ||
607 | if (q->fq_root && log == q->fq_trees_log) | |
608 | return 0; | |
609 | ||
c3bd8549 ED |
610 | /* If XPS was setup, we can allocate memory on right NUMA node */ |
611 | array = fq_alloc_node(sizeof(struct rb_root) << log, | |
612 | netdev_queue_numa_node_read(sch->dev_queue)); | |
afe4fd06 ED |
613 | if (!array) |
614 | return -ENOMEM; | |
615 | ||
616 | for (idx = 0; idx < (1U << log); idx++) | |
617 | array[idx] = RB_ROOT; | |
618 | ||
2818fa0f ED |
619 | sch_tree_lock(sch); |
620 | ||
621 | old_fq_root = q->fq_root; | |
622 | if (old_fq_root) | |
623 | fq_rehash(q, old_fq_root, q->fq_trees_log, array, log); | |
624 | ||
afe4fd06 ED |
625 | q->fq_root = array; |
626 | q->fq_trees_log = log; | |
627 | ||
2818fa0f ED |
628 | sch_tree_unlock(sch); |
629 | ||
630 | fq_free(old_fq_root); | |
631 | ||
afe4fd06 ED |
632 | return 0; |
633 | } | |
634 | ||
635 | static const struct nla_policy fq_policy[TCA_FQ_MAX + 1] = { | |
636 | [TCA_FQ_PLIMIT] = { .type = NLA_U32 }, | |
637 | [TCA_FQ_FLOW_PLIMIT] = { .type = NLA_U32 }, | |
638 | [TCA_FQ_QUANTUM] = { .type = NLA_U32 }, | |
639 | [TCA_FQ_INITIAL_QUANTUM] = { .type = NLA_U32 }, | |
640 | [TCA_FQ_RATE_ENABLE] = { .type = NLA_U32 }, | |
641 | [TCA_FQ_FLOW_DEFAULT_RATE] = { .type = NLA_U32 }, | |
642 | [TCA_FQ_FLOW_MAX_RATE] = { .type = NLA_U32 }, | |
643 | [TCA_FQ_BUCKETS_LOG] = { .type = NLA_U32 }, | |
f52ed899 | 644 | [TCA_FQ_FLOW_REFILL_DELAY] = { .type = NLA_U32 }, |
afe4fd06 ED |
645 | }; |
646 | ||
647 | static int fq_change(struct Qdisc *sch, struct nlattr *opt) | |
648 | { | |
649 | struct fq_sched_data *q = qdisc_priv(sch); | |
650 | struct nlattr *tb[TCA_FQ_MAX + 1]; | |
651 | int err, drop_count = 0; | |
652 | u32 fq_log; | |
653 | ||
654 | if (!opt) | |
655 | return -EINVAL; | |
656 | ||
657 | err = nla_parse_nested(tb, TCA_FQ_MAX, opt, fq_policy); | |
658 | if (err < 0) | |
659 | return err; | |
660 | ||
661 | sch_tree_lock(sch); | |
662 | ||
663 | fq_log = q->fq_trees_log; | |
664 | ||
665 | if (tb[TCA_FQ_BUCKETS_LOG]) { | |
666 | u32 nval = nla_get_u32(tb[TCA_FQ_BUCKETS_LOG]); | |
667 | ||
668 | if (nval >= 1 && nval <= ilog2(256*1024)) | |
669 | fq_log = nval; | |
670 | else | |
671 | err = -EINVAL; | |
672 | } | |
673 | if (tb[TCA_FQ_PLIMIT]) | |
674 | sch->limit = nla_get_u32(tb[TCA_FQ_PLIMIT]); | |
675 | ||
676 | if (tb[TCA_FQ_FLOW_PLIMIT]) | |
677 | q->flow_plimit = nla_get_u32(tb[TCA_FQ_FLOW_PLIMIT]); | |
678 | ||
679 | if (tb[TCA_FQ_QUANTUM]) | |
680 | q->quantum = nla_get_u32(tb[TCA_FQ_QUANTUM]); | |
681 | ||
682 | if (tb[TCA_FQ_INITIAL_QUANTUM]) | |
ede869cd | 683 | q->initial_quantum = nla_get_u32(tb[TCA_FQ_INITIAL_QUANTUM]); |
afe4fd06 ED |
684 | |
685 | if (tb[TCA_FQ_FLOW_DEFAULT_RATE]) | |
65c5189a ED |
686 | pr_warn_ratelimited("sch_fq: defrate %u ignored.\n", |
687 | nla_get_u32(tb[TCA_FQ_FLOW_DEFAULT_RATE])); | |
afe4fd06 ED |
688 | |
689 | if (tb[TCA_FQ_FLOW_MAX_RATE]) | |
690 | q->flow_max_rate = nla_get_u32(tb[TCA_FQ_FLOW_MAX_RATE]); | |
691 | ||
692 | if (tb[TCA_FQ_RATE_ENABLE]) { | |
693 | u32 enable = nla_get_u32(tb[TCA_FQ_RATE_ENABLE]); | |
694 | ||
695 | if (enable <= 1) | |
696 | q->rate_enable = enable; | |
697 | else | |
698 | err = -EINVAL; | |
699 | } | |
700 | ||
f52ed899 ED |
701 | if (tb[TCA_FQ_FLOW_REFILL_DELAY]) { |
702 | u32 usecs_delay = nla_get_u32(tb[TCA_FQ_FLOW_REFILL_DELAY]) ; | |
703 | ||
704 | q->flow_refill_delay = usecs_to_jiffies(usecs_delay); | |
705 | } | |
706 | ||
2818fa0f ED |
707 | if (!err) { |
708 | sch_tree_unlock(sch); | |
c3bd8549 | 709 | err = fq_resize(sch, fq_log); |
2818fa0f ED |
710 | sch_tree_lock(sch); |
711 | } | |
afe4fd06 ED |
712 | while (sch->q.qlen > sch->limit) { |
713 | struct sk_buff *skb = fq_dequeue(sch); | |
714 | ||
8d34ce10 ED |
715 | if (!skb) |
716 | break; | |
afe4fd06 ED |
717 | kfree_skb(skb); |
718 | drop_count++; | |
719 | } | |
720 | qdisc_tree_decrease_qlen(sch, drop_count); | |
721 | ||
722 | sch_tree_unlock(sch); | |
723 | return err; | |
724 | } | |
725 | ||
726 | static void fq_destroy(struct Qdisc *sch) | |
727 | { | |
728 | struct fq_sched_data *q = qdisc_priv(sch); | |
afe4fd06 | 729 | |
8d34ce10 | 730 | fq_reset(sch); |
c3bd8549 | 731 | fq_free(q->fq_root); |
afe4fd06 ED |
732 | qdisc_watchdog_cancel(&q->watchdog); |
733 | } | |
734 | ||
735 | static int fq_init(struct Qdisc *sch, struct nlattr *opt) | |
736 | { | |
737 | struct fq_sched_data *q = qdisc_priv(sch); | |
738 | int err; | |
739 | ||
740 | sch->limit = 10000; | |
741 | q->flow_plimit = 100; | |
742 | q->quantum = 2 * psched_mtu(qdisc_dev(sch)); | |
743 | q->initial_quantum = 10 * psched_mtu(qdisc_dev(sch)); | |
f52ed899 | 744 | q->flow_refill_delay = msecs_to_jiffies(40); |
afe4fd06 ED |
745 | q->flow_max_rate = ~0U; |
746 | q->rate_enable = 1; | |
747 | q->new_flows.first = NULL; | |
748 | q->old_flows.first = NULL; | |
749 | q->delayed = RB_ROOT; | |
750 | q->fq_root = NULL; | |
751 | q->fq_trees_log = ilog2(1024); | |
752 | qdisc_watchdog_init(&q->watchdog, sch); | |
753 | ||
754 | if (opt) | |
755 | err = fq_change(sch, opt); | |
756 | else | |
c3bd8549 | 757 | err = fq_resize(sch, q->fq_trees_log); |
afe4fd06 ED |
758 | |
759 | return err; | |
760 | } | |
761 | ||
762 | static int fq_dump(struct Qdisc *sch, struct sk_buff *skb) | |
763 | { | |
764 | struct fq_sched_data *q = qdisc_priv(sch); | |
765 | struct nlattr *opts; | |
766 | ||
767 | opts = nla_nest_start(skb, TCA_OPTIONS); | |
768 | if (opts == NULL) | |
769 | goto nla_put_failure; | |
770 | ||
65c5189a ED |
771 | /* TCA_FQ_FLOW_DEFAULT_RATE is not used anymore */ |
772 | ||
afe4fd06 ED |
773 | if (nla_put_u32(skb, TCA_FQ_PLIMIT, sch->limit) || |
774 | nla_put_u32(skb, TCA_FQ_FLOW_PLIMIT, q->flow_plimit) || | |
775 | nla_put_u32(skb, TCA_FQ_QUANTUM, q->quantum) || | |
776 | nla_put_u32(skb, TCA_FQ_INITIAL_QUANTUM, q->initial_quantum) || | |
777 | nla_put_u32(skb, TCA_FQ_RATE_ENABLE, q->rate_enable) || | |
afe4fd06 | 778 | nla_put_u32(skb, TCA_FQ_FLOW_MAX_RATE, q->flow_max_rate) || |
f52ed899 ED |
779 | nla_put_u32(skb, TCA_FQ_FLOW_REFILL_DELAY, |
780 | jiffies_to_usecs(q->flow_refill_delay)) || | |
afe4fd06 ED |
781 | nla_put_u32(skb, TCA_FQ_BUCKETS_LOG, q->fq_trees_log)) |
782 | goto nla_put_failure; | |
783 | ||
784 | nla_nest_end(skb, opts); | |
785 | return skb->len; | |
786 | ||
787 | nla_put_failure: | |
788 | return -1; | |
789 | } | |
790 | ||
791 | static int fq_dump_stats(struct Qdisc *sch, struct gnet_dump *d) | |
792 | { | |
793 | struct fq_sched_data *q = qdisc_priv(sch); | |
794 | u64 now = ktime_to_ns(ktime_get()); | |
795 | struct tc_fq_qd_stats st = { | |
796 | .gc_flows = q->stat_gc_flows, | |
797 | .highprio_packets = q->stat_internal_packets, | |
798 | .tcp_retrans = q->stat_tcp_retrans, | |
799 | .throttled = q->stat_throttled, | |
800 | .flows_plimit = q->stat_flows_plimit, | |
801 | .pkts_too_long = q->stat_pkts_too_long, | |
802 | .allocation_errors = q->stat_allocation_errors, | |
803 | .flows = q->flows, | |
804 | .inactive_flows = q->inactive_flows, | |
805 | .throttled_flows = q->throttled_flows, | |
806 | .time_next_delayed_flow = q->time_next_delayed_flow - now, | |
807 | }; | |
808 | ||
809 | return gnet_stats_copy_app(d, &st, sizeof(st)); | |
810 | } | |
811 | ||
812 | static struct Qdisc_ops fq_qdisc_ops __read_mostly = { | |
813 | .id = "fq", | |
814 | .priv_size = sizeof(struct fq_sched_data), | |
815 | ||
816 | .enqueue = fq_enqueue, | |
817 | .dequeue = fq_dequeue, | |
818 | .peek = qdisc_peek_dequeued, | |
819 | .init = fq_init, | |
820 | .reset = fq_reset, | |
821 | .destroy = fq_destroy, | |
822 | .change = fq_change, | |
823 | .dump = fq_dump, | |
824 | .dump_stats = fq_dump_stats, | |
825 | .owner = THIS_MODULE, | |
826 | }; | |
827 | ||
828 | static int __init fq_module_init(void) | |
829 | { | |
830 | int ret; | |
831 | ||
832 | fq_flow_cachep = kmem_cache_create("fq_flow_cache", | |
833 | sizeof(struct fq_flow), | |
834 | 0, 0, NULL); | |
835 | if (!fq_flow_cachep) | |
836 | return -ENOMEM; | |
837 | ||
838 | ret = register_qdisc(&fq_qdisc_ops); | |
839 | if (ret) | |
840 | kmem_cache_destroy(fq_flow_cachep); | |
841 | return ret; | |
842 | } | |
843 | ||
844 | static void __exit fq_module_exit(void) | |
845 | { | |
846 | unregister_qdisc(&fq_qdisc_ops); | |
847 | kmem_cache_destroy(fq_flow_cachep); | |
848 | } | |
849 | ||
850 | module_init(fq_module_init) | |
851 | module_exit(fq_module_exit) | |
852 | MODULE_AUTHOR("Eric Dumazet"); | |
853 | MODULE_LICENSE("GPL"); |