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1da177e4 LT |
1 | /* vim: ts=8 sw=8 |
2 | * net/sched/sch_htb.c Hierarchical token bucket, feed tree version | |
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 | * Authors: Martin Devera, <devik@cdi.cz> | |
10 | * | |
11 | * Credits (in time order) for older HTB versions: | |
12 | * Stef Coene <stef.coene@docum.org> | |
13 | * HTB support at LARTC mailing list | |
14 | * Ondrej Kraus, <krauso@barr.cz> | |
15 | * found missing INIT_QDISC(htb) | |
16 | * Vladimir Smelhaus, Aamer Akhter, Bert Hubert | |
17 | * helped a lot to locate nasty class stall bug | |
18 | * Andi Kleen, Jamal Hadi, Bert Hubert | |
19 | * code review and helpful comments on shaping | |
20 | * Tomasz Wrona, <tw@eter.tym.pl> | |
21 | * created test case so that I was able to fix nasty bug | |
22 | * Wilfried Weissmann | |
23 | * spotted bug in dequeue code and helped with fix | |
24 | * Jiri Fojtasek | |
25 | * fixed requeue routine | |
26 | * and many others. thanks. | |
27 | * | |
28 | * $Id: sch_htb.c,v 1.25 2003/12/07 11:08:25 devik Exp devik $ | |
29 | */ | |
1da177e4 LT |
30 | #include <linux/module.h> |
31 | #include <asm/uaccess.h> | |
32 | #include <asm/system.h> | |
33 | #include <linux/bitops.h> | |
34 | #include <linux/types.h> | |
35 | #include <linux/kernel.h> | |
36 | #include <linux/sched.h> | |
37 | #include <linux/string.h> | |
38 | #include <linux/mm.h> | |
39 | #include <linux/socket.h> | |
40 | #include <linux/sockios.h> | |
41 | #include <linux/in.h> | |
42 | #include <linux/errno.h> | |
43 | #include <linux/interrupt.h> | |
44 | #include <linux/if_ether.h> | |
45 | #include <linux/inet.h> | |
46 | #include <linux/netdevice.h> | |
47 | #include <linux/etherdevice.h> | |
48 | #include <linux/notifier.h> | |
49 | #include <net/ip.h> | |
50 | #include <net/route.h> | |
51 | #include <linux/skbuff.h> | |
52 | #include <linux/list.h> | |
53 | #include <linux/compiler.h> | |
54 | #include <net/sock.h> | |
55 | #include <net/pkt_sched.h> | |
56 | #include <linux/rbtree.h> | |
57 | ||
58 | /* HTB algorithm. | |
59 | Author: devik@cdi.cz | |
60 | ======================================================================== | |
61 | HTB is like TBF with multiple classes. It is also similar to CBQ because | |
62 | it allows to assign priority to each class in hierarchy. | |
63 | In fact it is another implementation of Floyd's formal sharing. | |
64 | ||
65 | Levels: | |
66 | Each class is assigned level. Leaf has ALWAYS level 0 and root | |
67 | classes have level TC_HTB_MAXDEPTH-1. Interior nodes has level | |
68 | one less than their parent. | |
69 | */ | |
70 | ||
71 | #define HTB_HSIZE 16 /* classid hash size */ | |
72 | #define HTB_EWMAC 2 /* rate average over HTB_EWMAC*HTB_HSIZE sec */ | |
1da177e4 LT |
73 | #define HTB_RATECM 1 /* whether to use rate computer */ |
74 | #define HTB_HYSTERESIS 1/* whether to use mode hysteresis for speedup */ | |
1da177e4 LT |
75 | #define HTB_VER 0x30011 /* major must be matched with number suplied by TC as version */ |
76 | ||
77 | #if HTB_VER >> 16 != TC_HTB_PROTOVER | |
78 | #error "Mismatched sch_htb.c and pkt_sch.h" | |
79 | #endif | |
80 | ||
1da177e4 LT |
81 | /* used internaly to keep status of single class */ |
82 | enum htb_cmode { | |
83 | HTB_CANT_SEND, /* class can't send and can't borrow */ | |
84 | HTB_MAY_BORROW, /* class can't send but may borrow */ | |
85 | HTB_CAN_SEND /* class can send */ | |
86 | }; | |
87 | ||
88 | /* interior & leaf nodes; props specific to leaves are marked L: */ | |
89 | struct htb_class | |
90 | { | |
1da177e4 LT |
91 | /* general class parameters */ |
92 | u32 classid; | |
93 | struct gnet_stats_basic bstats; | |
94 | struct gnet_stats_queue qstats; | |
95 | struct gnet_stats_rate_est rate_est; | |
96 | struct tc_htb_xstats xstats;/* our special stats */ | |
97 | int refcnt; /* usage count of this class */ | |
98 | ||
99 | #ifdef HTB_RATECM | |
100 | /* rate measurement counters */ | |
101 | unsigned long rate_bytes,sum_bytes; | |
102 | unsigned long rate_packets,sum_packets; | |
103 | #endif | |
104 | ||
105 | /* topology */ | |
106 | int level; /* our level (see above) */ | |
107 | struct htb_class *parent; /* parent class */ | |
108 | struct list_head hlist; /* classid hash list item */ | |
109 | struct list_head sibling; /* sibling list item */ | |
110 | struct list_head children; /* children list */ | |
111 | ||
112 | union { | |
113 | struct htb_class_leaf { | |
114 | struct Qdisc *q; | |
115 | int prio; | |
116 | int aprio; | |
117 | int quantum; | |
118 | int deficit[TC_HTB_MAXDEPTH]; | |
119 | struct list_head drop_list; | |
120 | } leaf; | |
121 | struct htb_class_inner { | |
122 | struct rb_root feed[TC_HTB_NUMPRIO]; /* feed trees */ | |
123 | struct rb_node *ptr[TC_HTB_NUMPRIO]; /* current class ptr */ | |
124 | /* When class changes from state 1->2 and disconnects from | |
125 | parent's feed then we lost ptr value and start from the | |
126 | first child again. Here we store classid of the | |
127 | last valid ptr (used when ptr is NULL). */ | |
128 | u32 last_ptr_id[TC_HTB_NUMPRIO]; | |
129 | } inner; | |
130 | } un; | |
131 | struct rb_node node[TC_HTB_NUMPRIO]; /* node for self or feed tree */ | |
132 | struct rb_node pq_node; /* node for event queue */ | |
133 | unsigned long pq_key; /* the same type as jiffies global */ | |
134 | ||
135 | int prio_activity; /* for which prios are we active */ | |
136 | enum htb_cmode cmode; /* current mode of the class */ | |
137 | ||
138 | /* class attached filters */ | |
139 | struct tcf_proto *filter_list; | |
140 | int filter_cnt; | |
141 | ||
142 | int warned; /* only one warning about non work conserving .. */ | |
143 | ||
144 | /* token bucket parameters */ | |
145 | struct qdisc_rate_table *rate; /* rate table of the class itself */ | |
146 | struct qdisc_rate_table *ceil; /* ceiling rate (limits borrows too) */ | |
147 | long buffer,cbuffer; /* token bucket depth/rate */ | |
b3a62519 | 148 | psched_tdiff_t mbuffer; /* max wait time */ |
1da177e4 LT |
149 | long tokens,ctokens; /* current number of tokens */ |
150 | psched_time_t t_c; /* checkpoint time */ | |
151 | }; | |
152 | ||
153 | /* TODO: maybe compute rate when size is too large .. or drop ? */ | |
154 | static __inline__ long L2T(struct htb_class *cl,struct qdisc_rate_table *rate, | |
155 | int size) | |
156 | { | |
157 | int slot = size >> rate->rate.cell_log; | |
158 | if (slot > 255) { | |
159 | cl->xstats.giants++; | |
160 | slot = 255; | |
161 | } | |
162 | return rate->data[slot]; | |
163 | } | |
164 | ||
165 | struct htb_sched | |
166 | { | |
167 | struct list_head root; /* root classes list */ | |
168 | struct list_head hash[HTB_HSIZE]; /* hashed by classid */ | |
169 | struct list_head drops[TC_HTB_NUMPRIO]; /* active leaves (for drops) */ | |
170 | ||
171 | /* self list - roots of self generating tree */ | |
172 | struct rb_root row[TC_HTB_MAXDEPTH][TC_HTB_NUMPRIO]; | |
173 | int row_mask[TC_HTB_MAXDEPTH]; | |
174 | struct rb_node *ptr[TC_HTB_MAXDEPTH][TC_HTB_NUMPRIO]; | |
175 | u32 last_ptr_id[TC_HTB_MAXDEPTH][TC_HTB_NUMPRIO]; | |
176 | ||
177 | /* self wait list - roots of wait PQs per row */ | |
178 | struct rb_root wait_pq[TC_HTB_MAXDEPTH]; | |
179 | ||
180 | /* time of nearest event per level (row) */ | |
181 | unsigned long near_ev_cache[TC_HTB_MAXDEPTH]; | |
182 | ||
183 | /* cached value of jiffies in dequeue */ | |
184 | unsigned long jiffies; | |
185 | ||
186 | /* whether we hit non-work conserving class during this dequeue; we use */ | |
187 | int nwc_hit; /* this to disable mindelay complaint in dequeue */ | |
188 | ||
189 | int defcls; /* class where unclassified flows go to */ | |
1da177e4 LT |
190 | |
191 | /* filters for qdisc itself */ | |
192 | struct tcf_proto *filter_list; | |
193 | int filter_cnt; | |
194 | ||
195 | int rate2quantum; /* quant = rate / rate2quantum */ | |
196 | psched_time_t now; /* cached dequeue time */ | |
197 | struct timer_list timer; /* send delay timer */ | |
198 | #ifdef HTB_RATECM | |
199 | struct timer_list rttim; /* rate computer timer */ | |
200 | int recmp_bucket; /* which hash bucket to recompute next */ | |
201 | #endif | |
202 | ||
203 | /* non shaped skbs; let them go directly thru */ | |
204 | struct sk_buff_head direct_queue; | |
205 | int direct_qlen; /* max qlen of above */ | |
206 | ||
207 | long direct_pkts; | |
208 | }; | |
209 | ||
210 | /* compute hash of size HTB_HSIZE for given handle */ | |
211 | static __inline__ int htb_hash(u32 h) | |
212 | { | |
213 | #if HTB_HSIZE != 16 | |
214 | #error "Declare new hash for your HTB_HSIZE" | |
215 | #endif | |
216 | h ^= h>>8; /* stolen from cbq_hash */ | |
217 | h ^= h>>4; | |
218 | return h & 0xf; | |
219 | } | |
220 | ||
221 | /* find class in global hash table using given handle */ | |
222 | static __inline__ struct htb_class *htb_find(u32 handle, struct Qdisc *sch) | |
223 | { | |
224 | struct htb_sched *q = qdisc_priv(sch); | |
225 | struct list_head *p; | |
226 | if (TC_H_MAJ(handle) != sch->handle) | |
227 | return NULL; | |
228 | ||
229 | list_for_each (p,q->hash+htb_hash(handle)) { | |
230 | struct htb_class *cl = list_entry(p,struct htb_class,hlist); | |
231 | if (cl->classid == handle) | |
232 | return cl; | |
233 | } | |
234 | return NULL; | |
235 | } | |
236 | ||
237 | /** | |
238 | * htb_classify - classify a packet into class | |
239 | * | |
240 | * It returns NULL if the packet should be dropped or -1 if the packet | |
241 | * should be passed directly thru. In all other cases leaf class is returned. | |
242 | * We allow direct class selection by classid in priority. The we examine | |
243 | * filters in qdisc and in inner nodes (if higher filter points to the inner | |
244 | * node). If we end up with classid MAJOR:0 we enqueue the skb into special | |
245 | * internal fifo (direct). These packets then go directly thru. If we still | |
246 | * have no valid leaf we try to use MAJOR:default leaf. It still unsuccessfull | |
247 | * then finish and return direct queue. | |
248 | */ | |
249 | #define HTB_DIRECT (struct htb_class*)-1 | |
250 | static inline u32 htb_classid(struct htb_class *cl) | |
251 | { | |
252 | return (cl && cl != HTB_DIRECT) ? cl->classid : TC_H_UNSPEC; | |
253 | } | |
254 | ||
255 | static struct htb_class *htb_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr) | |
256 | { | |
257 | struct htb_sched *q = qdisc_priv(sch); | |
258 | struct htb_class *cl; | |
259 | struct tcf_result res; | |
260 | struct tcf_proto *tcf; | |
261 | int result; | |
262 | ||
263 | /* allow to select class by setting skb->priority to valid classid; | |
264 | note that nfmark can be used too by attaching filter fw with no | |
265 | rules in it */ | |
266 | if (skb->priority == sch->handle) | |
267 | return HTB_DIRECT; /* X:0 (direct flow) selected */ | |
268 | if ((cl = htb_find(skb->priority,sch)) != NULL && cl->level == 0) | |
269 | return cl; | |
270 | ||
29f1df6c | 271 | *qerr = NET_XMIT_BYPASS; |
1da177e4 LT |
272 | tcf = q->filter_list; |
273 | while (tcf && (result = tc_classify(skb, tcf, &res)) >= 0) { | |
274 | #ifdef CONFIG_NET_CLS_ACT | |
275 | switch (result) { | |
276 | case TC_ACT_QUEUED: | |
277 | case TC_ACT_STOLEN: | |
278 | *qerr = NET_XMIT_SUCCESS; | |
279 | case TC_ACT_SHOT: | |
280 | return NULL; | |
281 | } | |
282 | #elif defined(CONFIG_NET_CLS_POLICE) | |
283 | if (result == TC_POLICE_SHOT) | |
284 | return HTB_DIRECT; | |
285 | #endif | |
286 | if ((cl = (void*)res.class) == NULL) { | |
287 | if (res.classid == sch->handle) | |
288 | return HTB_DIRECT; /* X:0 (direct flow) */ | |
289 | if ((cl = htb_find(res.classid,sch)) == NULL) | |
290 | break; /* filter selected invalid classid */ | |
291 | } | |
292 | if (!cl->level) | |
293 | return cl; /* we hit leaf; return it */ | |
294 | ||
295 | /* we have got inner class; apply inner filter chain */ | |
296 | tcf = cl->filter_list; | |
297 | } | |
298 | /* classification failed; try to use default class */ | |
299 | cl = htb_find(TC_H_MAKE(TC_H_MAJ(sch->handle),q->defcls),sch); | |
300 | if (!cl || cl->level) | |
301 | return HTB_DIRECT; /* bad default .. this is safe bet */ | |
302 | return cl; | |
303 | } | |
304 | ||
1da177e4 LT |
305 | /** |
306 | * htb_add_to_id_tree - adds class to the round robin list | |
307 | * | |
308 | * Routine adds class to the list (actually tree) sorted by classid. | |
309 | * Make sure that class is not already on such list for given prio. | |
310 | */ | |
3bf72957 | 311 | static void htb_add_to_id_tree (struct rb_root *root, |
1da177e4 LT |
312 | struct htb_class *cl,int prio) |
313 | { | |
314 | struct rb_node **p = &root->rb_node, *parent = NULL; | |
3bf72957 | 315 | |
1da177e4 LT |
316 | while (*p) { |
317 | struct htb_class *c; parent = *p; | |
318 | c = rb_entry(parent, struct htb_class, node[prio]); | |
3bf72957 | 319 | |
1da177e4 LT |
320 | if (cl->classid > c->classid) |
321 | p = &parent->rb_right; | |
322 | else | |
323 | p = &parent->rb_left; | |
324 | } | |
325 | rb_link_node(&cl->node[prio], parent, p); | |
326 | rb_insert_color(&cl->node[prio], root); | |
327 | } | |
328 | ||
329 | /** | |
330 | * htb_add_to_wait_tree - adds class to the event queue with delay | |
331 | * | |
332 | * The class is added to priority event queue to indicate that class will | |
333 | * change its mode in cl->pq_key microseconds. Make sure that class is not | |
334 | * already in the queue. | |
335 | */ | |
336 | static void htb_add_to_wait_tree (struct htb_sched *q, | |
3bf72957 | 337 | struct htb_class *cl,long delay) |
1da177e4 LT |
338 | { |
339 | struct rb_node **p = &q->wait_pq[cl->level].rb_node, *parent = NULL; | |
3bf72957 | 340 | |
1da177e4 LT |
341 | cl->pq_key = q->jiffies + PSCHED_US2JIFFIE(delay); |
342 | if (cl->pq_key == q->jiffies) | |
343 | cl->pq_key++; | |
344 | ||
345 | /* update the nearest event cache */ | |
346 | if (time_after(q->near_ev_cache[cl->level], cl->pq_key)) | |
347 | q->near_ev_cache[cl->level] = cl->pq_key; | |
348 | ||
349 | while (*p) { | |
350 | struct htb_class *c; parent = *p; | |
351 | c = rb_entry(parent, struct htb_class, pq_node); | |
352 | if (time_after_eq(cl->pq_key, c->pq_key)) | |
353 | p = &parent->rb_right; | |
354 | else | |
355 | p = &parent->rb_left; | |
356 | } | |
357 | rb_link_node(&cl->pq_node, parent, p); | |
358 | rb_insert_color(&cl->pq_node, &q->wait_pq[cl->level]); | |
359 | } | |
360 | ||
361 | /** | |
362 | * htb_next_rb_node - finds next node in binary tree | |
363 | * | |
364 | * When we are past last key we return NULL. | |
365 | * Average complexity is 2 steps per call. | |
366 | */ | |
367 | static void htb_next_rb_node(struct rb_node **n) | |
368 | { | |
369 | *n = rb_next(*n); | |
370 | } | |
371 | ||
372 | /** | |
373 | * htb_add_class_to_row - add class to its row | |
374 | * | |
375 | * The class is added to row at priorities marked in mask. | |
376 | * It does nothing if mask == 0. | |
377 | */ | |
378 | static inline void htb_add_class_to_row(struct htb_sched *q, | |
379 | struct htb_class *cl,int mask) | |
380 | { | |
1da177e4 LT |
381 | q->row_mask[cl->level] |= mask; |
382 | while (mask) { | |
383 | int prio = ffz(~mask); | |
384 | mask &= ~(1 << prio); | |
3bf72957 | 385 | htb_add_to_id_tree(q->row[cl->level]+prio,cl,prio); |
1da177e4 LT |
386 | } |
387 | } | |
388 | ||
389 | /** | |
390 | * htb_remove_class_from_row - removes class from its row | |
391 | * | |
392 | * The class is removed from row at priorities marked in mask. | |
393 | * It does nothing if mask == 0. | |
394 | */ | |
395 | static __inline__ void htb_remove_class_from_row(struct htb_sched *q, | |
396 | struct htb_class *cl,int mask) | |
397 | { | |
398 | int m = 0; | |
3bf72957 | 399 | |
1da177e4 LT |
400 | while (mask) { |
401 | int prio = ffz(~mask); | |
402 | mask &= ~(1 << prio); | |
403 | if (q->ptr[cl->level][prio] == cl->node+prio) | |
404 | htb_next_rb_node(q->ptr[cl->level]+prio); | |
3bf72957 | 405 | rb_erase(cl->node + prio,q->row[cl->level]+prio); |
1da177e4 LT |
406 | if (!q->row[cl->level][prio].rb_node) |
407 | m |= 1 << prio; | |
408 | } | |
1da177e4 LT |
409 | q->row_mask[cl->level] &= ~m; |
410 | } | |
411 | ||
412 | /** | |
413 | * htb_activate_prios - creates active classe's feed chain | |
414 | * | |
415 | * The class is connected to ancestors and/or appropriate rows | |
416 | * for priorities it is participating on. cl->cmode must be new | |
417 | * (activated) mode. It does nothing if cl->prio_activity == 0. | |
418 | */ | |
419 | static void htb_activate_prios(struct htb_sched *q,struct htb_class *cl) | |
420 | { | |
421 | struct htb_class *p = cl->parent; | |
422 | long m,mask = cl->prio_activity; | |
1da177e4 LT |
423 | |
424 | while (cl->cmode == HTB_MAY_BORROW && p && mask) { | |
3bf72957 | 425 | |
1da177e4 LT |
426 | m = mask; while (m) { |
427 | int prio = ffz(~m); | |
428 | m &= ~(1 << prio); | |
429 | ||
430 | if (p->un.inner.feed[prio].rb_node) | |
431 | /* parent already has its feed in use so that | |
432 | reset bit in mask as parent is already ok */ | |
433 | mask &= ~(1 << prio); | |
434 | ||
3bf72957 | 435 | htb_add_to_id_tree(p->un.inner.feed+prio,cl,prio); |
1da177e4 | 436 | } |
1da177e4 LT |
437 | p->prio_activity |= mask; |
438 | cl = p; p = cl->parent; | |
3bf72957 | 439 | |
1da177e4 LT |
440 | } |
441 | if (cl->cmode == HTB_CAN_SEND && mask) | |
442 | htb_add_class_to_row(q,cl,mask); | |
443 | } | |
444 | ||
445 | /** | |
446 | * htb_deactivate_prios - remove class from feed chain | |
447 | * | |
448 | * cl->cmode must represent old mode (before deactivation). It does | |
449 | * nothing if cl->prio_activity == 0. Class is removed from all feed | |
450 | * chains and rows. | |
451 | */ | |
452 | static void htb_deactivate_prios(struct htb_sched *q, struct htb_class *cl) | |
453 | { | |
454 | struct htb_class *p = cl->parent; | |
455 | long m,mask = cl->prio_activity; | |
3bf72957 | 456 | |
1da177e4 LT |
457 | |
458 | while (cl->cmode == HTB_MAY_BORROW && p && mask) { | |
459 | m = mask; mask = 0; | |
460 | while (m) { | |
461 | int prio = ffz(~m); | |
462 | m &= ~(1 << prio); | |
463 | ||
464 | if (p->un.inner.ptr[prio] == cl->node+prio) { | |
465 | /* we are removing child which is pointed to from | |
466 | parent feed - forget the pointer but remember | |
467 | classid */ | |
468 | p->un.inner.last_ptr_id[prio] = cl->classid; | |
469 | p->un.inner.ptr[prio] = NULL; | |
470 | } | |
471 | ||
3bf72957 | 472 | rb_erase(cl->node + prio,p->un.inner.feed + prio); |
1da177e4 LT |
473 | |
474 | if (!p->un.inner.feed[prio].rb_node) | |
475 | mask |= 1 << prio; | |
476 | } | |
3bf72957 | 477 | |
1da177e4 LT |
478 | p->prio_activity &= ~mask; |
479 | cl = p; p = cl->parent; | |
3bf72957 | 480 | |
1da177e4 LT |
481 | } |
482 | if (cl->cmode == HTB_CAN_SEND && mask) | |
483 | htb_remove_class_from_row(q,cl,mask); | |
484 | } | |
485 | ||
486 | /** | |
487 | * htb_class_mode - computes and returns current class mode | |
488 | * | |
489 | * It computes cl's mode at time cl->t_c+diff and returns it. If mode | |
490 | * is not HTB_CAN_SEND then cl->pq_key is updated to time difference | |
491 | * from now to time when cl will change its state. | |
492 | * Also it is worth to note that class mode doesn't change simply | |
493 | * at cl->{c,}tokens == 0 but there can rather be hysteresis of | |
494 | * 0 .. -cl->{c,}buffer range. It is meant to limit number of | |
495 | * mode transitions per time unit. The speed gain is about 1/6. | |
496 | */ | |
497 | static __inline__ enum htb_cmode | |
498 | htb_class_mode(struct htb_class *cl,long *diff) | |
499 | { | |
500 | long toks; | |
501 | ||
502 | if ((toks = (cl->ctokens + *diff)) < ( | |
503 | #if HTB_HYSTERESIS | |
504 | cl->cmode != HTB_CANT_SEND ? -cl->cbuffer : | |
505 | #endif | |
506 | 0)) { | |
507 | *diff = -toks; | |
508 | return HTB_CANT_SEND; | |
509 | } | |
510 | if ((toks = (cl->tokens + *diff)) >= ( | |
511 | #if HTB_HYSTERESIS | |
512 | cl->cmode == HTB_CAN_SEND ? -cl->buffer : | |
513 | #endif | |
514 | 0)) | |
515 | return HTB_CAN_SEND; | |
516 | ||
517 | *diff = -toks; | |
518 | return HTB_MAY_BORROW; | |
519 | } | |
520 | ||
521 | /** | |
522 | * htb_change_class_mode - changes classe's mode | |
523 | * | |
524 | * This should be the only way how to change classe's mode under normal | |
525 | * cirsumstances. Routine will update feed lists linkage, change mode | |
526 | * and add class to the wait event queue if appropriate. New mode should | |
527 | * be different from old one and cl->pq_key has to be valid if changing | |
528 | * to mode other than HTB_CAN_SEND (see htb_add_to_wait_tree). | |
529 | */ | |
530 | static void | |
531 | htb_change_class_mode(struct htb_sched *q, struct htb_class *cl, long *diff) | |
532 | { | |
533 | enum htb_cmode new_mode = htb_class_mode(cl,diff); | |
534 | ||
1da177e4 LT |
535 | |
536 | if (new_mode == cl->cmode) | |
537 | return; | |
538 | ||
539 | if (cl->prio_activity) { /* not necessary: speed optimization */ | |
540 | if (cl->cmode != HTB_CANT_SEND) | |
541 | htb_deactivate_prios(q,cl); | |
542 | cl->cmode = new_mode; | |
543 | if (new_mode != HTB_CANT_SEND) | |
544 | htb_activate_prios(q,cl); | |
545 | } else | |
546 | cl->cmode = new_mode; | |
547 | } | |
548 | ||
549 | /** | |
550 | * htb_activate - inserts leaf cl into appropriate active feeds | |
551 | * | |
552 | * Routine learns (new) priority of leaf and activates feed chain | |
553 | * for the prio. It can be called on already active leaf safely. | |
554 | * It also adds leaf into droplist. | |
555 | */ | |
556 | static __inline__ void htb_activate(struct htb_sched *q,struct htb_class *cl) | |
557 | { | |
558 | BUG_TRAP(!cl->level && cl->un.leaf.q && cl->un.leaf.q->q.qlen); | |
3bf72957 | 559 | |
1da177e4 LT |
560 | if (!cl->prio_activity) { |
561 | cl->prio_activity = 1 << (cl->un.leaf.aprio = cl->un.leaf.prio); | |
562 | htb_activate_prios(q,cl); | |
563 | list_add_tail(&cl->un.leaf.drop_list,q->drops+cl->un.leaf.aprio); | |
564 | } | |
565 | } | |
566 | ||
567 | /** | |
568 | * htb_deactivate - remove leaf cl from active feeds | |
569 | * | |
570 | * Make sure that leaf is active. In the other words it can't be called | |
571 | * with non-active leaf. It also removes class from the drop list. | |
572 | */ | |
573 | static __inline__ void | |
574 | htb_deactivate(struct htb_sched *q,struct htb_class *cl) | |
575 | { | |
576 | BUG_TRAP(cl->prio_activity); | |
3bf72957 | 577 | |
1da177e4 LT |
578 | htb_deactivate_prios(q,cl); |
579 | cl->prio_activity = 0; | |
580 | list_del_init(&cl->un.leaf.drop_list); | |
581 | } | |
582 | ||
583 | static int htb_enqueue(struct sk_buff *skb, struct Qdisc *sch) | |
584 | { | |
585 | int ret; | |
586 | struct htb_sched *q = qdisc_priv(sch); | |
587 | struct htb_class *cl = htb_classify(skb,sch,&ret); | |
588 | ||
589 | if (cl == HTB_DIRECT) { | |
590 | /* enqueue to helper queue */ | |
591 | if (q->direct_queue.qlen < q->direct_qlen) { | |
592 | __skb_queue_tail(&q->direct_queue, skb); | |
593 | q->direct_pkts++; | |
033d8999 AS |
594 | } else { |
595 | kfree_skb(skb); | |
596 | sch->qstats.drops++; | |
597 | return NET_XMIT_DROP; | |
1da177e4 LT |
598 | } |
599 | #ifdef CONFIG_NET_CLS_ACT | |
600 | } else if (!cl) { | |
29f1df6c | 601 | if (ret == NET_XMIT_BYPASS) |
1da177e4 LT |
602 | sch->qstats.drops++; |
603 | kfree_skb (skb); | |
604 | return ret; | |
605 | #endif | |
606 | } else if (cl->un.leaf.q->enqueue(skb, cl->un.leaf.q) != NET_XMIT_SUCCESS) { | |
607 | sch->qstats.drops++; | |
608 | cl->qstats.drops++; | |
609 | return NET_XMIT_DROP; | |
610 | } else { | |
611 | cl->bstats.packets++; cl->bstats.bytes += skb->len; | |
612 | htb_activate (q,cl); | |
613 | } | |
614 | ||
615 | sch->q.qlen++; | |
616 | sch->bstats.packets++; sch->bstats.bytes += skb->len; | |
1da177e4 LT |
617 | return NET_XMIT_SUCCESS; |
618 | } | |
619 | ||
620 | /* TODO: requeuing packet charges it to policers again !! */ | |
621 | static int htb_requeue(struct sk_buff *skb, struct Qdisc *sch) | |
622 | { | |
623 | struct htb_sched *q = qdisc_priv(sch); | |
624 | int ret = NET_XMIT_SUCCESS; | |
625 | struct htb_class *cl = htb_classify(skb,sch, &ret); | |
626 | struct sk_buff *tskb; | |
627 | ||
628 | if (cl == HTB_DIRECT || !cl) { | |
629 | /* enqueue to helper queue */ | |
630 | if (q->direct_queue.qlen < q->direct_qlen && cl) { | |
631 | __skb_queue_head(&q->direct_queue, skb); | |
632 | } else { | |
633 | __skb_queue_head(&q->direct_queue, skb); | |
634 | tskb = __skb_dequeue_tail(&q->direct_queue); | |
635 | kfree_skb (tskb); | |
636 | sch->qstats.drops++; | |
637 | return NET_XMIT_CN; | |
638 | } | |
639 | } else if (cl->un.leaf.q->ops->requeue(skb, cl->un.leaf.q) != NET_XMIT_SUCCESS) { | |
640 | sch->qstats.drops++; | |
641 | cl->qstats.drops++; | |
642 | return NET_XMIT_DROP; | |
643 | } else | |
644 | htb_activate (q,cl); | |
645 | ||
646 | sch->q.qlen++; | |
647 | sch->qstats.requeues++; | |
1da177e4 LT |
648 | return NET_XMIT_SUCCESS; |
649 | } | |
650 | ||
651 | static void htb_timer(unsigned long arg) | |
652 | { | |
653 | struct Qdisc *sch = (struct Qdisc*)arg; | |
654 | sch->flags &= ~TCQ_F_THROTTLED; | |
655 | wmb(); | |
656 | netif_schedule(sch->dev); | |
657 | } | |
658 | ||
659 | #ifdef HTB_RATECM | |
660 | #define RT_GEN(D,R) R+=D-(R/HTB_EWMAC);D=0 | |
661 | static void htb_rate_timer(unsigned long arg) | |
662 | { | |
663 | struct Qdisc *sch = (struct Qdisc*)arg; | |
664 | struct htb_sched *q = qdisc_priv(sch); | |
665 | struct list_head *p; | |
666 | ||
667 | /* lock queue so that we can muck with it */ | |
9ac961ee | 668 | spin_lock_bh(&sch->dev->queue_lock); |
1da177e4 LT |
669 | |
670 | q->rttim.expires = jiffies + HZ; | |
671 | add_timer(&q->rttim); | |
672 | ||
673 | /* scan and recompute one bucket at time */ | |
674 | if (++q->recmp_bucket >= HTB_HSIZE) | |
675 | q->recmp_bucket = 0; | |
676 | list_for_each (p,q->hash+q->recmp_bucket) { | |
677 | struct htb_class *cl = list_entry(p,struct htb_class,hlist); | |
3bf72957 | 678 | |
1da177e4 LT |
679 | RT_GEN (cl->sum_bytes,cl->rate_bytes); |
680 | RT_GEN (cl->sum_packets,cl->rate_packets); | |
681 | } | |
9ac961ee | 682 | spin_unlock_bh(&sch->dev->queue_lock); |
1da177e4 LT |
683 | } |
684 | #endif | |
685 | ||
686 | /** | |
687 | * htb_charge_class - charges amount "bytes" to leaf and ancestors | |
688 | * | |
689 | * Routine assumes that packet "bytes" long was dequeued from leaf cl | |
690 | * borrowing from "level". It accounts bytes to ceil leaky bucket for | |
691 | * leaf and all ancestors and to rate bucket for ancestors at levels | |
692 | * "level" and higher. It also handles possible change of mode resulting | |
693 | * from the update. Note that mode can also increase here (MAY_BORROW to | |
694 | * CAN_SEND) because we can use more precise clock that event queue here. | |
695 | * In such case we remove class from event queue first. | |
696 | */ | |
697 | static void htb_charge_class(struct htb_sched *q,struct htb_class *cl, | |
698 | int level,int bytes) | |
699 | { | |
700 | long toks,diff; | |
701 | enum htb_cmode old_mode; | |
1da177e4 LT |
702 | |
703 | #define HTB_ACCNT(T,B,R) toks = diff + cl->T; \ | |
704 | if (toks > cl->B) toks = cl->B; \ | |
705 | toks -= L2T(cl, cl->R, bytes); \ | |
706 | if (toks <= -cl->mbuffer) toks = 1-cl->mbuffer; \ | |
707 | cl->T = toks | |
708 | ||
709 | while (cl) { | |
1da177e4 | 710 | diff = PSCHED_TDIFF_SAFE(q->now, cl->t_c, (u32)cl->mbuffer); |
1da177e4 LT |
711 | if (cl->level >= level) { |
712 | if (cl->level == level) cl->xstats.lends++; | |
713 | HTB_ACCNT (tokens,buffer,rate); | |
714 | } else { | |
715 | cl->xstats.borrows++; | |
716 | cl->tokens += diff; /* we moved t_c; update tokens */ | |
717 | } | |
718 | HTB_ACCNT (ctokens,cbuffer,ceil); | |
719 | cl->t_c = q->now; | |
1da177e4 LT |
720 | |
721 | old_mode = cl->cmode; diff = 0; | |
722 | htb_change_class_mode(q,cl,&diff); | |
723 | if (old_mode != cl->cmode) { | |
724 | if (old_mode != HTB_CAN_SEND) | |
3bf72957 | 725 | rb_erase(&cl->pq_node,q->wait_pq+cl->level); |
1da177e4 | 726 | if (cl->cmode != HTB_CAN_SEND) |
3bf72957 | 727 | htb_add_to_wait_tree (q,cl,diff); |
1da177e4 LT |
728 | } |
729 | ||
730 | #ifdef HTB_RATECM | |
731 | /* update rate counters */ | |
732 | cl->sum_bytes += bytes; cl->sum_packets++; | |
733 | #endif | |
734 | ||
735 | /* update byte stats except for leaves which are already updated */ | |
736 | if (cl->level) { | |
737 | cl->bstats.bytes += bytes; | |
738 | cl->bstats.packets++; | |
739 | } | |
740 | cl = cl->parent; | |
741 | } | |
742 | } | |
743 | ||
744 | /** | |
745 | * htb_do_events - make mode changes to classes at the level | |
746 | * | |
747 | * Scans event queue for pending events and applies them. Returns jiffies to | |
748 | * next pending event (0 for no event in pq). | |
749 | * Note: Aplied are events whose have cl->pq_key <= jiffies. | |
750 | */ | |
751 | static long htb_do_events(struct htb_sched *q,int level) | |
752 | { | |
753 | int i; | |
3bf72957 | 754 | |
1da177e4 LT |
755 | for (i = 0; i < 500; i++) { |
756 | struct htb_class *cl; | |
757 | long diff; | |
758 | struct rb_node *p = q->wait_pq[level].rb_node; | |
759 | if (!p) return 0; | |
760 | while (p->rb_left) p = p->rb_left; | |
761 | ||
762 | cl = rb_entry(p, struct htb_class, pq_node); | |
763 | if (time_after(cl->pq_key, q->jiffies)) { | |
1da177e4 LT |
764 | return cl->pq_key - q->jiffies; |
765 | } | |
3bf72957 | 766 | rb_erase(p,q->wait_pq+level); |
1da177e4 | 767 | diff = PSCHED_TDIFF_SAFE(q->now, cl->t_c, (u32)cl->mbuffer); |
1da177e4 LT |
768 | htb_change_class_mode(q,cl,&diff); |
769 | if (cl->cmode != HTB_CAN_SEND) | |
3bf72957 | 770 | htb_add_to_wait_tree (q,cl,diff); |
1da177e4 LT |
771 | } |
772 | if (net_ratelimit()) | |
773 | printk(KERN_WARNING "htb: too many events !\n"); | |
774 | return HZ/10; | |
775 | } | |
776 | ||
777 | /* Returns class->node+prio from id-tree where classe's id is >= id. NULL | |
778 | is no such one exists. */ | |
779 | static struct rb_node * | |
780 | htb_id_find_next_upper(int prio,struct rb_node *n,u32 id) | |
781 | { | |
782 | struct rb_node *r = NULL; | |
783 | while (n) { | |
784 | struct htb_class *cl = rb_entry(n,struct htb_class,node[prio]); | |
785 | if (id == cl->classid) return n; | |
786 | ||
787 | if (id > cl->classid) { | |
788 | n = n->rb_right; | |
789 | } else { | |
790 | r = n; | |
791 | n = n->rb_left; | |
792 | } | |
793 | } | |
794 | return r; | |
795 | } | |
796 | ||
797 | /** | |
798 | * htb_lookup_leaf - returns next leaf class in DRR order | |
799 | * | |
800 | * Find leaf where current feed pointers points to. | |
801 | */ | |
802 | static struct htb_class * | |
3bf72957 | 803 | htb_lookup_leaf(struct rb_root *tree,int prio,struct rb_node **pptr,u32 *pid) |
1da177e4 LT |
804 | { |
805 | int i; | |
806 | struct { | |
807 | struct rb_node *root; | |
808 | struct rb_node **pptr; | |
809 | u32 *pid; | |
810 | } stk[TC_HTB_MAXDEPTH],*sp = stk; | |
811 | ||
812 | BUG_TRAP(tree->rb_node); | |
813 | sp->root = tree->rb_node; | |
814 | sp->pptr = pptr; | |
815 | sp->pid = pid; | |
816 | ||
817 | for (i = 0; i < 65535; i++) { | |
1da177e4 LT |
818 | if (!*sp->pptr && *sp->pid) { |
819 | /* ptr was invalidated but id is valid - try to recover | |
820 | the original or next ptr */ | |
821 | *sp->pptr = htb_id_find_next_upper(prio,sp->root,*sp->pid); | |
822 | } | |
823 | *sp->pid = 0; /* ptr is valid now so that remove this hint as it | |
824 | can become out of date quickly */ | |
825 | if (!*sp->pptr) { /* we are at right end; rewind & go up */ | |
826 | *sp->pptr = sp->root; | |
827 | while ((*sp->pptr)->rb_left) | |
828 | *sp->pptr = (*sp->pptr)->rb_left; | |
829 | if (sp > stk) { | |
830 | sp--; | |
831 | BUG_TRAP(*sp->pptr); if(!*sp->pptr) return NULL; | |
832 | htb_next_rb_node (sp->pptr); | |
833 | } | |
834 | } else { | |
835 | struct htb_class *cl; | |
836 | cl = rb_entry(*sp->pptr,struct htb_class,node[prio]); | |
1da177e4 LT |
837 | if (!cl->level) |
838 | return cl; | |
839 | (++sp)->root = cl->un.inner.feed[prio].rb_node; | |
840 | sp->pptr = cl->un.inner.ptr+prio; | |
841 | sp->pid = cl->un.inner.last_ptr_id+prio; | |
842 | } | |
843 | } | |
844 | BUG_TRAP(0); | |
845 | return NULL; | |
846 | } | |
847 | ||
848 | /* dequeues packet at given priority and level; call only if | |
849 | you are sure that there is active class at prio/level */ | |
850 | static struct sk_buff * | |
851 | htb_dequeue_tree(struct htb_sched *q,int prio,int level) | |
852 | { | |
853 | struct sk_buff *skb = NULL; | |
854 | struct htb_class *cl,*start; | |
855 | /* look initial class up in the row */ | |
3bf72957 | 856 | start = cl = htb_lookup_leaf (q->row[level]+prio,prio, |
1da177e4 LT |
857 | q->ptr[level]+prio,q->last_ptr_id[level]+prio); |
858 | ||
859 | do { | |
860 | next: | |
861 | BUG_TRAP(cl); | |
862 | if (!cl) return NULL; | |
1da177e4 LT |
863 | |
864 | /* class can be empty - it is unlikely but can be true if leaf | |
865 | qdisc drops packets in enqueue routine or if someone used | |
866 | graft operation on the leaf since last dequeue; | |
867 | simply deactivate and skip such class */ | |
868 | if (unlikely(cl->un.leaf.q->q.qlen == 0)) { | |
869 | struct htb_class *next; | |
870 | htb_deactivate(q,cl); | |
871 | ||
872 | /* row/level might become empty */ | |
873 | if ((q->row_mask[level] & (1 << prio)) == 0) | |
874 | return NULL; | |
875 | ||
3bf72957 | 876 | next = htb_lookup_leaf (q->row[level]+prio, |
1da177e4 LT |
877 | prio,q->ptr[level]+prio,q->last_ptr_id[level]+prio); |
878 | ||
879 | if (cl == start) /* fix start if we just deleted it */ | |
880 | start = next; | |
881 | cl = next; | |
882 | goto next; | |
883 | } | |
884 | ||
885 | if (likely((skb = cl->un.leaf.q->dequeue(cl->un.leaf.q)) != NULL)) | |
886 | break; | |
887 | if (!cl->warned) { | |
888 | printk(KERN_WARNING "htb: class %X isn't work conserving ?!\n",cl->classid); | |
889 | cl->warned = 1; | |
890 | } | |
891 | q->nwc_hit++; | |
892 | htb_next_rb_node((level?cl->parent->un.inner.ptr:q->ptr[0])+prio); | |
3bf72957 | 893 | cl = htb_lookup_leaf (q->row[level]+prio,prio,q->ptr[level]+prio, |
1da177e4 LT |
894 | q->last_ptr_id[level]+prio); |
895 | ||
896 | } while (cl != start); | |
897 | ||
898 | if (likely(skb != NULL)) { | |
899 | if ((cl->un.leaf.deficit[level] -= skb->len) < 0) { | |
1da177e4 LT |
900 | cl->un.leaf.deficit[level] += cl->un.leaf.quantum; |
901 | htb_next_rb_node((level?cl->parent->un.inner.ptr:q->ptr[0])+prio); | |
902 | } | |
903 | /* this used to be after charge_class but this constelation | |
904 | gives us slightly better performance */ | |
905 | if (!cl->un.leaf.q->q.qlen) | |
906 | htb_deactivate (q,cl); | |
907 | htb_charge_class (q,cl,level,skb->len); | |
908 | } | |
909 | return skb; | |
910 | } | |
911 | ||
912 | static void htb_delay_by(struct Qdisc *sch,long delay) | |
913 | { | |
914 | struct htb_sched *q = qdisc_priv(sch); | |
915 | if (delay <= 0) delay = 1; | |
916 | if (unlikely(delay > 5*HZ)) { | |
917 | if (net_ratelimit()) | |
918 | printk(KERN_INFO "HTB delay %ld > 5sec\n", delay); | |
919 | delay = 5*HZ; | |
920 | } | |
921 | /* why don't use jiffies here ? because expires can be in past */ | |
922 | mod_timer(&q->timer, q->jiffies + delay); | |
923 | sch->flags |= TCQ_F_THROTTLED; | |
924 | sch->qstats.overlimits++; | |
1da177e4 LT |
925 | } |
926 | ||
927 | static struct sk_buff *htb_dequeue(struct Qdisc *sch) | |
928 | { | |
929 | struct sk_buff *skb = NULL; | |
930 | struct htb_sched *q = qdisc_priv(sch); | |
931 | int level; | |
932 | long min_delay; | |
1da177e4 LT |
933 | |
934 | q->jiffies = jiffies; | |
1da177e4 LT |
935 | |
936 | /* try to dequeue direct packets as high prio (!) to minimize cpu work */ | |
937 | if ((skb = __skb_dequeue(&q->direct_queue)) != NULL) { | |
938 | sch->flags &= ~TCQ_F_THROTTLED; | |
939 | sch->q.qlen--; | |
940 | return skb; | |
941 | } | |
942 | ||
943 | if (!sch->q.qlen) goto fin; | |
944 | PSCHED_GET_TIME(q->now); | |
945 | ||
946 | min_delay = LONG_MAX; | |
947 | q->nwc_hit = 0; | |
948 | for (level = 0; level < TC_HTB_MAXDEPTH; level++) { | |
949 | /* common case optimization - skip event handler quickly */ | |
950 | int m; | |
951 | long delay; | |
952 | if (time_after_eq(q->jiffies, q->near_ev_cache[level])) { | |
953 | delay = htb_do_events(q,level); | |
954 | q->near_ev_cache[level] = q->jiffies + (delay ? delay : HZ); | |
1da177e4 LT |
955 | } else |
956 | delay = q->near_ev_cache[level] - q->jiffies; | |
957 | ||
958 | if (delay && min_delay > delay) | |
959 | min_delay = delay; | |
960 | m = ~q->row_mask[level]; | |
961 | while (m != (int)(-1)) { | |
962 | int prio = ffz (m); | |
963 | m |= 1 << prio; | |
964 | skb = htb_dequeue_tree(q,prio,level); | |
965 | if (likely(skb != NULL)) { | |
966 | sch->q.qlen--; | |
967 | sch->flags &= ~TCQ_F_THROTTLED; | |
968 | goto fin; | |
969 | } | |
970 | } | |
971 | } | |
1da177e4 LT |
972 | htb_delay_by (sch,min_delay > 5*HZ ? 5*HZ : min_delay); |
973 | fin: | |
1da177e4 LT |
974 | return skb; |
975 | } | |
976 | ||
977 | /* try to drop from each class (by prio) until one succeed */ | |
978 | static unsigned int htb_drop(struct Qdisc* sch) | |
979 | { | |
980 | struct htb_sched *q = qdisc_priv(sch); | |
981 | int prio; | |
982 | ||
983 | for (prio = TC_HTB_NUMPRIO - 1; prio >= 0; prio--) { | |
984 | struct list_head *p; | |
985 | list_for_each (p,q->drops+prio) { | |
986 | struct htb_class *cl = list_entry(p, struct htb_class, | |
987 | un.leaf.drop_list); | |
988 | unsigned int len; | |
989 | if (cl->un.leaf.q->ops->drop && | |
990 | (len = cl->un.leaf.q->ops->drop(cl->un.leaf.q))) { | |
991 | sch->q.qlen--; | |
992 | if (!cl->un.leaf.q->q.qlen) | |
993 | htb_deactivate (q,cl); | |
994 | return len; | |
995 | } | |
996 | } | |
997 | } | |
998 | return 0; | |
999 | } | |
1000 | ||
1001 | /* reset all classes */ | |
1002 | /* always caled under BH & queue lock */ | |
1003 | static void htb_reset(struct Qdisc* sch) | |
1004 | { | |
1005 | struct htb_sched *q = qdisc_priv(sch); | |
1006 | int i; | |
1da177e4 LT |
1007 | |
1008 | for (i = 0; i < HTB_HSIZE; i++) { | |
1009 | struct list_head *p; | |
1010 | list_for_each (p,q->hash+i) { | |
1011 | struct htb_class *cl = list_entry(p,struct htb_class,hlist); | |
1012 | if (cl->level) | |
1013 | memset(&cl->un.inner,0,sizeof(cl->un.inner)); | |
1014 | else { | |
1015 | if (cl->un.leaf.q) | |
1016 | qdisc_reset(cl->un.leaf.q); | |
1017 | INIT_LIST_HEAD(&cl->un.leaf.drop_list); | |
1018 | } | |
1019 | cl->prio_activity = 0; | |
1020 | cl->cmode = HTB_CAN_SEND; | |
1da177e4 LT |
1021 | |
1022 | } | |
1023 | } | |
1024 | sch->flags &= ~TCQ_F_THROTTLED; | |
1025 | del_timer(&q->timer); | |
1026 | __skb_queue_purge(&q->direct_queue); | |
1027 | sch->q.qlen = 0; | |
1028 | memset(q->row,0,sizeof(q->row)); | |
1029 | memset(q->row_mask,0,sizeof(q->row_mask)); | |
1030 | memset(q->wait_pq,0,sizeof(q->wait_pq)); | |
1031 | memset(q->ptr,0,sizeof(q->ptr)); | |
1032 | for (i = 0; i < TC_HTB_NUMPRIO; i++) | |
1033 | INIT_LIST_HEAD(q->drops+i); | |
1034 | } | |
1035 | ||
1036 | static int htb_init(struct Qdisc *sch, struct rtattr *opt) | |
1037 | { | |
1038 | struct htb_sched *q = qdisc_priv(sch); | |
1039 | struct rtattr *tb[TCA_HTB_INIT]; | |
1040 | struct tc_htb_glob *gopt; | |
1041 | int i; | |
1da177e4 LT |
1042 | if (!opt || rtattr_parse_nested(tb, TCA_HTB_INIT, opt) || |
1043 | tb[TCA_HTB_INIT-1] == NULL || | |
1044 | RTA_PAYLOAD(tb[TCA_HTB_INIT-1]) < sizeof(*gopt)) { | |
1045 | printk(KERN_ERR "HTB: hey probably you have bad tc tool ?\n"); | |
1046 | return -EINVAL; | |
1047 | } | |
1048 | gopt = RTA_DATA(tb[TCA_HTB_INIT-1]); | |
1049 | if (gopt->version != HTB_VER >> 16) { | |
1050 | printk(KERN_ERR "HTB: need tc/htb version %d (minor is %d), you have %d\n", | |
1051 | HTB_VER >> 16,HTB_VER & 0xffff,gopt->version); | |
1052 | return -EINVAL; | |
1053 | } | |
1da177e4 LT |
1054 | |
1055 | INIT_LIST_HEAD(&q->root); | |
1056 | for (i = 0; i < HTB_HSIZE; i++) | |
1057 | INIT_LIST_HEAD(q->hash+i); | |
1058 | for (i = 0; i < TC_HTB_NUMPRIO; i++) | |
1059 | INIT_LIST_HEAD(q->drops+i); | |
1060 | ||
1061 | init_timer(&q->timer); | |
1062 | skb_queue_head_init(&q->direct_queue); | |
1063 | ||
1064 | q->direct_qlen = sch->dev->tx_queue_len; | |
1065 | if (q->direct_qlen < 2) /* some devices have zero tx_queue_len */ | |
1066 | q->direct_qlen = 2; | |
1067 | q->timer.function = htb_timer; | |
1068 | q->timer.data = (unsigned long)sch; | |
1069 | ||
1070 | #ifdef HTB_RATECM | |
1071 | init_timer(&q->rttim); | |
1072 | q->rttim.function = htb_rate_timer; | |
1073 | q->rttim.data = (unsigned long)sch; | |
1074 | q->rttim.expires = jiffies + HZ; | |
1075 | add_timer(&q->rttim); | |
1076 | #endif | |
1077 | if ((q->rate2quantum = gopt->rate2quantum) < 1) | |
1078 | q->rate2quantum = 1; | |
1079 | q->defcls = gopt->defcls; | |
1080 | ||
1081 | return 0; | |
1082 | } | |
1083 | ||
1084 | static int htb_dump(struct Qdisc *sch, struct sk_buff *skb) | |
1085 | { | |
1086 | struct htb_sched *q = qdisc_priv(sch); | |
1087 | unsigned char *b = skb->tail; | |
1088 | struct rtattr *rta; | |
1089 | struct tc_htb_glob gopt; | |
9ac961ee | 1090 | spin_lock_bh(&sch->dev->queue_lock); |
1da177e4 LT |
1091 | gopt.direct_pkts = q->direct_pkts; |
1092 | ||
1da177e4 LT |
1093 | gopt.version = HTB_VER; |
1094 | gopt.rate2quantum = q->rate2quantum; | |
1095 | gopt.defcls = q->defcls; | |
3bf72957 | 1096 | gopt.debug = 0; |
1da177e4 LT |
1097 | rta = (struct rtattr*)b; |
1098 | RTA_PUT(skb, TCA_OPTIONS, 0, NULL); | |
1099 | RTA_PUT(skb, TCA_HTB_INIT, sizeof(gopt), &gopt); | |
1100 | rta->rta_len = skb->tail - b; | |
9ac961ee | 1101 | spin_unlock_bh(&sch->dev->queue_lock); |
1da177e4 LT |
1102 | return skb->len; |
1103 | rtattr_failure: | |
9ac961ee | 1104 | spin_unlock_bh(&sch->dev->queue_lock); |
1da177e4 LT |
1105 | skb_trim(skb, skb->tail - skb->data); |
1106 | return -1; | |
1107 | } | |
1108 | ||
1109 | static int htb_dump_class(struct Qdisc *sch, unsigned long arg, | |
1110 | struct sk_buff *skb, struct tcmsg *tcm) | |
1111 | { | |
1da177e4 LT |
1112 | struct htb_class *cl = (struct htb_class*)arg; |
1113 | unsigned char *b = skb->tail; | |
1114 | struct rtattr *rta; | |
1115 | struct tc_htb_opt opt; | |
1116 | ||
9ac961ee | 1117 | spin_lock_bh(&sch->dev->queue_lock); |
1da177e4 LT |
1118 | tcm->tcm_parent = cl->parent ? cl->parent->classid : TC_H_ROOT; |
1119 | tcm->tcm_handle = cl->classid; | |
1120 | if (!cl->level && cl->un.leaf.q) | |
1121 | tcm->tcm_info = cl->un.leaf.q->handle; | |
1122 | ||
1123 | rta = (struct rtattr*)b; | |
1124 | RTA_PUT(skb, TCA_OPTIONS, 0, NULL); | |
1125 | ||
1126 | memset (&opt,0,sizeof(opt)); | |
1127 | ||
1128 | opt.rate = cl->rate->rate; opt.buffer = cl->buffer; | |
1129 | opt.ceil = cl->ceil->rate; opt.cbuffer = cl->cbuffer; | |
1130 | opt.quantum = cl->un.leaf.quantum; opt.prio = cl->un.leaf.prio; | |
1131 | opt.level = cl->level; | |
1132 | RTA_PUT(skb, TCA_HTB_PARMS, sizeof(opt), &opt); | |
1133 | rta->rta_len = skb->tail - b; | |
9ac961ee | 1134 | spin_unlock_bh(&sch->dev->queue_lock); |
1da177e4 LT |
1135 | return skb->len; |
1136 | rtattr_failure: | |
9ac961ee | 1137 | spin_unlock_bh(&sch->dev->queue_lock); |
1da177e4 LT |
1138 | skb_trim(skb, b - skb->data); |
1139 | return -1; | |
1140 | } | |
1141 | ||
1142 | static int | |
1143 | htb_dump_class_stats(struct Qdisc *sch, unsigned long arg, | |
1144 | struct gnet_dump *d) | |
1145 | { | |
1146 | struct htb_class *cl = (struct htb_class*)arg; | |
1147 | ||
1148 | #ifdef HTB_RATECM | |
1149 | cl->rate_est.bps = cl->rate_bytes/(HTB_EWMAC*HTB_HSIZE); | |
1150 | cl->rate_est.pps = cl->rate_packets/(HTB_EWMAC*HTB_HSIZE); | |
1151 | #endif | |
1152 | ||
1153 | if (!cl->level && cl->un.leaf.q) | |
1154 | cl->qstats.qlen = cl->un.leaf.q->q.qlen; | |
1155 | cl->xstats.tokens = cl->tokens; | |
1156 | cl->xstats.ctokens = cl->ctokens; | |
1157 | ||
1158 | if (gnet_stats_copy_basic(d, &cl->bstats) < 0 || | |
1159 | gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 || | |
1160 | gnet_stats_copy_queue(d, &cl->qstats) < 0) | |
1161 | return -1; | |
1162 | ||
1163 | return gnet_stats_copy_app(d, &cl->xstats, sizeof(cl->xstats)); | |
1164 | } | |
1165 | ||
1166 | static int htb_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new, | |
1167 | struct Qdisc **old) | |
1168 | { | |
1169 | struct htb_class *cl = (struct htb_class*)arg; | |
1170 | ||
1171 | if (cl && !cl->level) { | |
1172 | if (new == NULL && (new = qdisc_create_dflt(sch->dev, | |
1173 | &pfifo_qdisc_ops)) == NULL) | |
1174 | return -ENOBUFS; | |
1175 | sch_tree_lock(sch); | |
1176 | if ((*old = xchg(&cl->un.leaf.q, new)) != NULL) { | |
1177 | if (cl->prio_activity) | |
1178 | htb_deactivate (qdisc_priv(sch),cl); | |
1179 | ||
1180 | /* TODO: is it correct ? Why CBQ doesn't do it ? */ | |
1181 | sch->q.qlen -= (*old)->q.qlen; | |
1182 | qdisc_reset(*old); | |
1183 | } | |
1184 | sch_tree_unlock(sch); | |
1185 | return 0; | |
1186 | } | |
1187 | return -ENOENT; | |
1188 | } | |
1189 | ||
1190 | static struct Qdisc * htb_leaf(struct Qdisc *sch, unsigned long arg) | |
1191 | { | |
1192 | struct htb_class *cl = (struct htb_class*)arg; | |
1193 | return (cl && !cl->level) ? cl->un.leaf.q : NULL; | |
1194 | } | |
1195 | ||
1196 | static unsigned long htb_get(struct Qdisc *sch, u32 classid) | |
1197 | { | |
1da177e4 | 1198 | struct htb_class *cl = htb_find(classid,sch); |
1da177e4 LT |
1199 | if (cl) |
1200 | cl->refcnt++; | |
1201 | return (unsigned long)cl; | |
1202 | } | |
1203 | ||
1204 | static void htb_destroy_filters(struct tcf_proto **fl) | |
1205 | { | |
1206 | struct tcf_proto *tp; | |
1207 | ||
1208 | while ((tp = *fl) != NULL) { | |
1209 | *fl = tp->next; | |
1210 | tcf_destroy(tp); | |
1211 | } | |
1212 | } | |
1213 | ||
1214 | static void htb_destroy_class(struct Qdisc* sch,struct htb_class *cl) | |
1215 | { | |
1216 | struct htb_sched *q = qdisc_priv(sch); | |
1da177e4 LT |
1217 | if (!cl->level) { |
1218 | BUG_TRAP(cl->un.leaf.q); | |
1219 | sch->q.qlen -= cl->un.leaf.q->q.qlen; | |
1220 | qdisc_destroy(cl->un.leaf.q); | |
1221 | } | |
1222 | qdisc_put_rtab(cl->rate); | |
1223 | qdisc_put_rtab(cl->ceil); | |
1224 | ||
1225 | htb_destroy_filters (&cl->filter_list); | |
1226 | ||
1227 | while (!list_empty(&cl->children)) | |
1228 | htb_destroy_class (sch,list_entry(cl->children.next, | |
1229 | struct htb_class,sibling)); | |
1230 | ||
1231 | /* note: this delete may happen twice (see htb_delete) */ | |
1232 | list_del(&cl->hlist); | |
1233 | list_del(&cl->sibling); | |
1234 | ||
1235 | if (cl->prio_activity) | |
1236 | htb_deactivate (q,cl); | |
1237 | ||
1238 | if (cl->cmode != HTB_CAN_SEND) | |
3bf72957 | 1239 | rb_erase(&cl->pq_node,q->wait_pq+cl->level); |
1da177e4 LT |
1240 | |
1241 | kfree(cl); | |
1242 | } | |
1243 | ||
1244 | /* always caled under BH & queue lock */ | |
1245 | static void htb_destroy(struct Qdisc* sch) | |
1246 | { | |
1247 | struct htb_sched *q = qdisc_priv(sch); | |
1da177e4 LT |
1248 | |
1249 | del_timer_sync (&q->timer); | |
1250 | #ifdef HTB_RATECM | |
1251 | del_timer_sync (&q->rttim); | |
1252 | #endif | |
1253 | /* This line used to be after htb_destroy_class call below | |
1254 | and surprisingly it worked in 2.4. But it must precede it | |
1255 | because filter need its target class alive to be able to call | |
1256 | unbind_filter on it (without Oops). */ | |
1257 | htb_destroy_filters(&q->filter_list); | |
1258 | ||
1259 | while (!list_empty(&q->root)) | |
1260 | htb_destroy_class (sch,list_entry(q->root.next, | |
1261 | struct htb_class,sibling)); | |
1262 | ||
1263 | __skb_queue_purge(&q->direct_queue); | |
1264 | } | |
1265 | ||
1266 | static int htb_delete(struct Qdisc *sch, unsigned long arg) | |
1267 | { | |
1268 | struct htb_sched *q = qdisc_priv(sch); | |
1269 | struct htb_class *cl = (struct htb_class*)arg; | |
1da177e4 LT |
1270 | |
1271 | // TODO: why don't allow to delete subtree ? references ? does | |
1272 | // tc subsys quarantee us that in htb_destroy it holds no class | |
1273 | // refs so that we can remove children safely there ? | |
1274 | if (!list_empty(&cl->children) || cl->filter_cnt) | |
1275 | return -EBUSY; | |
1276 | ||
1277 | sch_tree_lock(sch); | |
1278 | ||
1279 | /* delete from hash and active; remainder in destroy_class */ | |
1280 | list_del_init(&cl->hlist); | |
1281 | if (cl->prio_activity) | |
1282 | htb_deactivate (q,cl); | |
1283 | ||
1284 | if (--cl->refcnt == 0) | |
1285 | htb_destroy_class(sch,cl); | |
1286 | ||
1287 | sch_tree_unlock(sch); | |
1288 | return 0; | |
1289 | } | |
1290 | ||
1291 | static void htb_put(struct Qdisc *sch, unsigned long arg) | |
1292 | { | |
1da177e4 | 1293 | struct htb_class *cl = (struct htb_class*)arg; |
1da177e4 LT |
1294 | |
1295 | if (--cl->refcnt == 0) | |
1296 | htb_destroy_class(sch,cl); | |
1297 | } | |
1298 | ||
1299 | static int htb_change_class(struct Qdisc *sch, u32 classid, | |
1300 | u32 parentid, struct rtattr **tca, unsigned long *arg) | |
1301 | { | |
1302 | int err = -EINVAL; | |
1303 | struct htb_sched *q = qdisc_priv(sch); | |
1304 | struct htb_class *cl = (struct htb_class*)*arg,*parent; | |
1305 | struct rtattr *opt = tca[TCA_OPTIONS-1]; | |
1306 | struct qdisc_rate_table *rtab = NULL, *ctab = NULL; | |
1307 | struct rtattr *tb[TCA_HTB_RTAB]; | |
1308 | struct tc_htb_opt *hopt; | |
1309 | ||
1310 | /* extract all subattrs from opt attr */ | |
1311 | if (!opt || rtattr_parse_nested(tb, TCA_HTB_RTAB, opt) || | |
1312 | tb[TCA_HTB_PARMS-1] == NULL || | |
1313 | RTA_PAYLOAD(tb[TCA_HTB_PARMS-1]) < sizeof(*hopt)) | |
1314 | goto failure; | |
1315 | ||
1316 | parent = parentid == TC_H_ROOT ? NULL : htb_find (parentid,sch); | |
1317 | ||
1318 | hopt = RTA_DATA(tb[TCA_HTB_PARMS-1]); | |
3bf72957 | 1319 | |
1da177e4 LT |
1320 | rtab = qdisc_get_rtab(&hopt->rate, tb[TCA_HTB_RTAB-1]); |
1321 | ctab = qdisc_get_rtab(&hopt->ceil, tb[TCA_HTB_CTAB-1]); | |
1322 | if (!rtab || !ctab) goto failure; | |
1323 | ||
1324 | if (!cl) { /* new class */ | |
1325 | struct Qdisc *new_q; | |
1326 | /* check for valid classid */ | |
1327 | if (!classid || TC_H_MAJ(classid^sch->handle) || htb_find(classid,sch)) | |
1328 | goto failure; | |
1329 | ||
1330 | /* check maximal depth */ | |
1331 | if (parent && parent->parent && parent->parent->level < 2) { | |
1332 | printk(KERN_ERR "htb: tree is too deep\n"); | |
1333 | goto failure; | |
1334 | } | |
1335 | err = -ENOBUFS; | |
0da974f4 | 1336 | if ((cl = kzalloc(sizeof(*cl), GFP_KERNEL)) == NULL) |
1da177e4 LT |
1337 | goto failure; |
1338 | ||
1da177e4 LT |
1339 | cl->refcnt = 1; |
1340 | INIT_LIST_HEAD(&cl->sibling); | |
1341 | INIT_LIST_HEAD(&cl->hlist); | |
1342 | INIT_LIST_HEAD(&cl->children); | |
1343 | INIT_LIST_HEAD(&cl->un.leaf.drop_list); | |
1da177e4 LT |
1344 | |
1345 | /* create leaf qdisc early because it uses kmalloc(GFP_KERNEL) | |
1346 | so that can't be used inside of sch_tree_lock | |
1347 | -- thanks to Karlis Peisenieks */ | |
1348 | new_q = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops); | |
1349 | sch_tree_lock(sch); | |
1350 | if (parent && !parent->level) { | |
1351 | /* turn parent into inner node */ | |
1352 | sch->q.qlen -= parent->un.leaf.q->q.qlen; | |
1353 | qdisc_destroy (parent->un.leaf.q); | |
1354 | if (parent->prio_activity) | |
1355 | htb_deactivate (q,parent); | |
1356 | ||
1357 | /* remove from evt list because of level change */ | |
1358 | if (parent->cmode != HTB_CAN_SEND) { | |
3bf72957 | 1359 | rb_erase(&parent->pq_node,q->wait_pq); |
1da177e4 LT |
1360 | parent->cmode = HTB_CAN_SEND; |
1361 | } | |
1362 | parent->level = (parent->parent ? parent->parent->level | |
1363 | : TC_HTB_MAXDEPTH) - 1; | |
1364 | memset (&parent->un.inner,0,sizeof(parent->un.inner)); | |
1365 | } | |
1366 | /* leaf (we) needs elementary qdisc */ | |
1367 | cl->un.leaf.q = new_q ? new_q : &noop_qdisc; | |
1368 | ||
1369 | cl->classid = classid; cl->parent = parent; | |
1370 | ||
1371 | /* set class to be in HTB_CAN_SEND state */ | |
1372 | cl->tokens = hopt->buffer; | |
1373 | cl->ctokens = hopt->cbuffer; | |
2724a1a5 | 1374 | cl->mbuffer = PSCHED_JIFFIE2US(HZ*60); /* 1min */ |
1da177e4 LT |
1375 | PSCHED_GET_TIME(cl->t_c); |
1376 | cl->cmode = HTB_CAN_SEND; | |
1377 | ||
1378 | /* attach to the hash list and parent's family */ | |
1379 | list_add_tail(&cl->hlist, q->hash+htb_hash(classid)); | |
1380 | list_add_tail(&cl->sibling, parent ? &parent->children : &q->root); | |
1da177e4 LT |
1381 | } else sch_tree_lock(sch); |
1382 | ||
1383 | /* it used to be a nasty bug here, we have to check that node | |
1384 | is really leaf before changing cl->un.leaf ! */ | |
1385 | if (!cl->level) { | |
1386 | cl->un.leaf.quantum = rtab->rate.rate / q->rate2quantum; | |
1387 | if (!hopt->quantum && cl->un.leaf.quantum < 1000) { | |
1388 | printk(KERN_WARNING "HTB: quantum of class %X is small. Consider r2q change.\n", cl->classid); | |
1389 | cl->un.leaf.quantum = 1000; | |
1390 | } | |
1391 | if (!hopt->quantum && cl->un.leaf.quantum > 200000) { | |
1392 | printk(KERN_WARNING "HTB: quantum of class %X is big. Consider r2q change.\n", cl->classid); | |
1393 | cl->un.leaf.quantum = 200000; | |
1394 | } | |
1395 | if (hopt->quantum) | |
1396 | cl->un.leaf.quantum = hopt->quantum; | |
1397 | if ((cl->un.leaf.prio = hopt->prio) >= TC_HTB_NUMPRIO) | |
1398 | cl->un.leaf.prio = TC_HTB_NUMPRIO - 1; | |
1399 | } | |
1400 | ||
1401 | cl->buffer = hopt->buffer; | |
1402 | cl->cbuffer = hopt->cbuffer; | |
1403 | if (cl->rate) qdisc_put_rtab(cl->rate); cl->rate = rtab; | |
1404 | if (cl->ceil) qdisc_put_rtab(cl->ceil); cl->ceil = ctab; | |
1405 | sch_tree_unlock(sch); | |
1406 | ||
1407 | *arg = (unsigned long)cl; | |
1408 | return 0; | |
1409 | ||
1410 | failure: | |
1411 | if (rtab) qdisc_put_rtab(rtab); | |
1412 | if (ctab) qdisc_put_rtab(ctab); | |
1413 | return err; | |
1414 | } | |
1415 | ||
1416 | static struct tcf_proto **htb_find_tcf(struct Qdisc *sch, unsigned long arg) | |
1417 | { | |
1418 | struct htb_sched *q = qdisc_priv(sch); | |
1419 | struct htb_class *cl = (struct htb_class *)arg; | |
1420 | struct tcf_proto **fl = cl ? &cl->filter_list : &q->filter_list; | |
3bf72957 | 1421 | |
1da177e4 LT |
1422 | return fl; |
1423 | } | |
1424 | ||
1425 | static unsigned long htb_bind_filter(struct Qdisc *sch, unsigned long parent, | |
1426 | u32 classid) | |
1427 | { | |
1428 | struct htb_sched *q = qdisc_priv(sch); | |
1429 | struct htb_class *cl = htb_find (classid,sch); | |
3bf72957 | 1430 | |
1da177e4 LT |
1431 | /*if (cl && !cl->level) return 0; |
1432 | The line above used to be there to prevent attaching filters to | |
1433 | leaves. But at least tc_index filter uses this just to get class | |
1434 | for other reasons so that we have to allow for it. | |
1435 | ---- | |
1436 | 19.6.2002 As Werner explained it is ok - bind filter is just | |
1437 | another way to "lock" the class - unlike "get" this lock can | |
1438 | be broken by class during destroy IIUC. | |
1439 | */ | |
1440 | if (cl) | |
1441 | cl->filter_cnt++; | |
1442 | else | |
1443 | q->filter_cnt++; | |
1444 | return (unsigned long)cl; | |
1445 | } | |
1446 | ||
1447 | static void htb_unbind_filter(struct Qdisc *sch, unsigned long arg) | |
1448 | { | |
1449 | struct htb_sched *q = qdisc_priv(sch); | |
1450 | struct htb_class *cl = (struct htb_class *)arg; | |
3bf72957 | 1451 | |
1da177e4 LT |
1452 | if (cl) |
1453 | cl->filter_cnt--; | |
1454 | else | |
1455 | q->filter_cnt--; | |
1456 | } | |
1457 | ||
1458 | static void htb_walk(struct Qdisc *sch, struct qdisc_walker *arg) | |
1459 | { | |
1460 | struct htb_sched *q = qdisc_priv(sch); | |
1461 | int i; | |
1462 | ||
1463 | if (arg->stop) | |
1464 | return; | |
1465 | ||
1466 | for (i = 0; i < HTB_HSIZE; i++) { | |
1467 | struct list_head *p; | |
1468 | list_for_each (p,q->hash+i) { | |
1469 | struct htb_class *cl = list_entry(p,struct htb_class,hlist); | |
1470 | if (arg->count < arg->skip) { | |
1471 | arg->count++; | |
1472 | continue; | |
1473 | } | |
1474 | if (arg->fn(sch, (unsigned long)cl, arg) < 0) { | |
1475 | arg->stop = 1; | |
1476 | return; | |
1477 | } | |
1478 | arg->count++; | |
1479 | } | |
1480 | } | |
1481 | } | |
1482 | ||
1483 | static struct Qdisc_class_ops htb_class_ops = { | |
1484 | .graft = htb_graft, | |
1485 | .leaf = htb_leaf, | |
1486 | .get = htb_get, | |
1487 | .put = htb_put, | |
1488 | .change = htb_change_class, | |
1489 | .delete = htb_delete, | |
1490 | .walk = htb_walk, | |
1491 | .tcf_chain = htb_find_tcf, | |
1492 | .bind_tcf = htb_bind_filter, | |
1493 | .unbind_tcf = htb_unbind_filter, | |
1494 | .dump = htb_dump_class, | |
1495 | .dump_stats = htb_dump_class_stats, | |
1496 | }; | |
1497 | ||
1498 | static struct Qdisc_ops htb_qdisc_ops = { | |
1499 | .next = NULL, | |
1500 | .cl_ops = &htb_class_ops, | |
1501 | .id = "htb", | |
1502 | .priv_size = sizeof(struct htb_sched), | |
1503 | .enqueue = htb_enqueue, | |
1504 | .dequeue = htb_dequeue, | |
1505 | .requeue = htb_requeue, | |
1506 | .drop = htb_drop, | |
1507 | .init = htb_init, | |
1508 | .reset = htb_reset, | |
1509 | .destroy = htb_destroy, | |
1510 | .change = NULL /* htb_change */, | |
1511 | .dump = htb_dump, | |
1512 | .owner = THIS_MODULE, | |
1513 | }; | |
1514 | ||
1515 | static int __init htb_module_init(void) | |
1516 | { | |
1517 | return register_qdisc(&htb_qdisc_ops); | |
1518 | } | |
1519 | static void __exit htb_module_exit(void) | |
1520 | { | |
1521 | unregister_qdisc(&htb_qdisc_ops); | |
1522 | } | |
1523 | module_init(htb_module_init) | |
1524 | module_exit(htb_module_exit) | |
1525 | MODULE_LICENSE("GPL"); |