blob: 558cc087e6023f687b616494a12768f6bebf7171 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* 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 */
30#include <linux/config.h>
31#include <linux/module.h>
32#include <asm/uaccess.h>
33#include <asm/system.h>
34#include <linux/bitops.h>
35#include <linux/types.h>
36#include <linux/kernel.h>
37#include <linux/sched.h>
38#include <linux/string.h>
39#include <linux/mm.h>
40#include <linux/socket.h>
41#include <linux/sockios.h>
42#include <linux/in.h>
43#include <linux/errno.h>
44#include <linux/interrupt.h>
45#include <linux/if_ether.h>
46#include <linux/inet.h>
47#include <linux/netdevice.h>
48#include <linux/etherdevice.h>
49#include <linux/notifier.h>
50#include <net/ip.h>
51#include <net/route.h>
52#include <linux/skbuff.h>
53#include <linux/list.h>
54#include <linux/compiler.h>
55#include <net/sock.h>
56#include <net/pkt_sched.h>
57#include <linux/rbtree.h>
58
59/* HTB algorithm.
60 Author: devik@cdi.cz
61 ========================================================================
62 HTB is like TBF with multiple classes. It is also similar to CBQ because
63 it allows to assign priority to each class in hierarchy.
64 In fact it is another implementation of Floyd's formal sharing.
65
66 Levels:
67 Each class is assigned level. Leaf has ALWAYS level 0 and root
68 classes have level TC_HTB_MAXDEPTH-1. Interior nodes has level
69 one less than their parent.
70*/
71
72#define HTB_HSIZE 16 /* classid hash size */
73#define HTB_EWMAC 2 /* rate average over HTB_EWMAC*HTB_HSIZE sec */
74#undef HTB_DEBUG /* compile debugging support (activated by tc tool) */
75#define HTB_RATECM 1 /* whether to use rate computer */
76#define HTB_HYSTERESIS 1/* whether to use mode hysteresis for speedup */
77#define HTB_QLOCK(S) spin_lock_bh(&(S)->dev->queue_lock)
78#define HTB_QUNLOCK(S) spin_unlock_bh(&(S)->dev->queue_lock)
79#define HTB_VER 0x30011 /* major must be matched with number suplied by TC as version */
80
81#if HTB_VER >> 16 != TC_HTB_PROTOVER
82#error "Mismatched sch_htb.c and pkt_sch.h"
83#endif
84
85/* debugging support; S is subsystem, these are defined:
86 0 - netlink messages
87 1 - enqueue
88 2 - drop & requeue
89 3 - dequeue main
90 4 - dequeue one prio DRR part
91 5 - dequeue class accounting
92 6 - class overlimit status computation
93 7 - hint tree
94 8 - event queue
95 10 - rate estimator
96 11 - classifier
97 12 - fast dequeue cache
98
99 L is level; 0 = none, 1 = basic info, 2 = detailed, 3 = full
100 q->debug uint32 contains 16 2-bit fields one for subsystem starting
101 from LSB
102 */
103#ifdef HTB_DEBUG
104#define HTB_DBG_COND(S,L) (((q->debug>>(2*S))&3) >= L)
105#define HTB_DBG(S,L,FMT,ARG...) if (HTB_DBG_COND(S,L)) \
106 printk(KERN_DEBUG FMT,##ARG)
107#define HTB_CHCL(cl) BUG_TRAP((cl)->magic == HTB_CMAGIC)
108#define HTB_PASSQ q,
109#define HTB_ARGQ struct htb_sched *q,
110#define static
111#undef __inline__
112#define __inline__
113#undef inline
114#define inline
115#define HTB_CMAGIC 0xFEFAFEF1
116#define htb_safe_rb_erase(N,R) do { BUG_TRAP((N)->rb_color != -1); \
117 if ((N)->rb_color == -1) break; \
118 rb_erase(N,R); \
119 (N)->rb_color = -1; } while (0)
120#else
121#define HTB_DBG_COND(S,L) (0)
122#define HTB_DBG(S,L,FMT,ARG...)
123#define HTB_PASSQ
124#define HTB_ARGQ
125#define HTB_CHCL(cl)
126#define htb_safe_rb_erase(N,R) rb_erase(N,R)
127#endif
128
129
130/* used internaly to keep status of single class */
131enum htb_cmode {
132 HTB_CANT_SEND, /* class can't send and can't borrow */
133 HTB_MAY_BORROW, /* class can't send but may borrow */
134 HTB_CAN_SEND /* class can send */
135};
136
137/* interior & leaf nodes; props specific to leaves are marked L: */
138struct htb_class
139{
140#ifdef HTB_DEBUG
141 unsigned magic;
142#endif
143 /* general class parameters */
144 u32 classid;
145 struct gnet_stats_basic bstats;
146 struct gnet_stats_queue qstats;
147 struct gnet_stats_rate_est rate_est;
148 struct tc_htb_xstats xstats;/* our special stats */
149 int refcnt; /* usage count of this class */
150
151#ifdef HTB_RATECM
152 /* rate measurement counters */
153 unsigned long rate_bytes,sum_bytes;
154 unsigned long rate_packets,sum_packets;
155#endif
156
157 /* topology */
158 int level; /* our level (see above) */
159 struct htb_class *parent; /* parent class */
160 struct list_head hlist; /* classid hash list item */
161 struct list_head sibling; /* sibling list item */
162 struct list_head children; /* children list */
163
164 union {
165 struct htb_class_leaf {
166 struct Qdisc *q;
167 int prio;
168 int aprio;
169 int quantum;
170 int deficit[TC_HTB_MAXDEPTH];
171 struct list_head drop_list;
172 } leaf;
173 struct htb_class_inner {
174 struct rb_root feed[TC_HTB_NUMPRIO]; /* feed trees */
175 struct rb_node *ptr[TC_HTB_NUMPRIO]; /* current class ptr */
176 /* When class changes from state 1->2 and disconnects from
177 parent's feed then we lost ptr value and start from the
178 first child again. Here we store classid of the
179 last valid ptr (used when ptr is NULL). */
180 u32 last_ptr_id[TC_HTB_NUMPRIO];
181 } inner;
182 } un;
183 struct rb_node node[TC_HTB_NUMPRIO]; /* node for self or feed tree */
184 struct rb_node pq_node; /* node for event queue */
185 unsigned long pq_key; /* the same type as jiffies global */
186
187 int prio_activity; /* for which prios are we active */
188 enum htb_cmode cmode; /* current mode of the class */
189
190 /* class attached filters */
191 struct tcf_proto *filter_list;
192 int filter_cnt;
193
194 int warned; /* only one warning about non work conserving .. */
195
196 /* token bucket parameters */
197 struct qdisc_rate_table *rate; /* rate table of the class itself */
198 struct qdisc_rate_table *ceil; /* ceiling rate (limits borrows too) */
199 long buffer,cbuffer; /* token bucket depth/rate */
200 long mbuffer; /* max wait time */
201 long tokens,ctokens; /* current number of tokens */
202 psched_time_t t_c; /* checkpoint time */
203};
204
205/* TODO: maybe compute rate when size is too large .. or drop ? */
206static __inline__ long L2T(struct htb_class *cl,struct qdisc_rate_table *rate,
207 int size)
208{
209 int slot = size >> rate->rate.cell_log;
210 if (slot > 255) {
211 cl->xstats.giants++;
212 slot = 255;
213 }
214 return rate->data[slot];
215}
216
217struct htb_sched
218{
219 struct list_head root; /* root classes list */
220 struct list_head hash[HTB_HSIZE]; /* hashed by classid */
221 struct list_head drops[TC_HTB_NUMPRIO]; /* active leaves (for drops) */
222
223 /* self list - roots of self generating tree */
224 struct rb_root row[TC_HTB_MAXDEPTH][TC_HTB_NUMPRIO];
225 int row_mask[TC_HTB_MAXDEPTH];
226 struct rb_node *ptr[TC_HTB_MAXDEPTH][TC_HTB_NUMPRIO];
227 u32 last_ptr_id[TC_HTB_MAXDEPTH][TC_HTB_NUMPRIO];
228
229 /* self wait list - roots of wait PQs per row */
230 struct rb_root wait_pq[TC_HTB_MAXDEPTH];
231
232 /* time of nearest event per level (row) */
233 unsigned long near_ev_cache[TC_HTB_MAXDEPTH];
234
235 /* cached value of jiffies in dequeue */
236 unsigned long jiffies;
237
238 /* whether we hit non-work conserving class during this dequeue; we use */
239 int nwc_hit; /* this to disable mindelay complaint in dequeue */
240
241 int defcls; /* class where unclassified flows go to */
242 u32 debug; /* subsystem debug levels */
243
244 /* filters for qdisc itself */
245 struct tcf_proto *filter_list;
246 int filter_cnt;
247
248 int rate2quantum; /* quant = rate / rate2quantum */
249 psched_time_t now; /* cached dequeue time */
250 struct timer_list timer; /* send delay timer */
251#ifdef HTB_RATECM
252 struct timer_list rttim; /* rate computer timer */
253 int recmp_bucket; /* which hash bucket to recompute next */
254#endif
255
256 /* non shaped skbs; let them go directly thru */
257 struct sk_buff_head direct_queue;
258 int direct_qlen; /* max qlen of above */
259
260 long direct_pkts;
261};
262
263/* compute hash of size HTB_HSIZE for given handle */
264static __inline__ int htb_hash(u32 h)
265{
266#if HTB_HSIZE != 16
267 #error "Declare new hash for your HTB_HSIZE"
268#endif
269 h ^= h>>8; /* stolen from cbq_hash */
270 h ^= h>>4;
271 return h & 0xf;
272}
273
274/* find class in global hash table using given handle */
275static __inline__ struct htb_class *htb_find(u32 handle, struct Qdisc *sch)
276{
277 struct htb_sched *q = qdisc_priv(sch);
278 struct list_head *p;
279 if (TC_H_MAJ(handle) != sch->handle)
280 return NULL;
281
282 list_for_each (p,q->hash+htb_hash(handle)) {
283 struct htb_class *cl = list_entry(p,struct htb_class,hlist);
284 if (cl->classid == handle)
285 return cl;
286 }
287 return NULL;
288}
289
290/**
291 * htb_classify - classify a packet into class
292 *
293 * It returns NULL if the packet should be dropped or -1 if the packet
294 * should be passed directly thru. In all other cases leaf class is returned.
295 * We allow direct class selection by classid in priority. The we examine
296 * filters in qdisc and in inner nodes (if higher filter points to the inner
297 * node). If we end up with classid MAJOR:0 we enqueue the skb into special
298 * internal fifo (direct). These packets then go directly thru. If we still
299 * have no valid leaf we try to use MAJOR:default leaf. It still unsuccessfull
300 * then finish and return direct queue.
301 */
302#define HTB_DIRECT (struct htb_class*)-1
303static inline u32 htb_classid(struct htb_class *cl)
304{
305 return (cl && cl != HTB_DIRECT) ? cl->classid : TC_H_UNSPEC;
306}
307
308static struct htb_class *htb_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
309{
310 struct htb_sched *q = qdisc_priv(sch);
311 struct htb_class *cl;
312 struct tcf_result res;
313 struct tcf_proto *tcf;
314 int result;
315
316 /* allow to select class by setting skb->priority to valid classid;
317 note that nfmark can be used too by attaching filter fw with no
318 rules in it */
319 if (skb->priority == sch->handle)
320 return HTB_DIRECT; /* X:0 (direct flow) selected */
321 if ((cl = htb_find(skb->priority,sch)) != NULL && cl->level == 0)
322 return cl;
323
324 *qerr = NET_XMIT_DROP;
325 tcf = q->filter_list;
326 while (tcf && (result = tc_classify(skb, tcf, &res)) >= 0) {
327#ifdef CONFIG_NET_CLS_ACT
328 switch (result) {
329 case TC_ACT_QUEUED:
330 case TC_ACT_STOLEN:
331 *qerr = NET_XMIT_SUCCESS;
332 case TC_ACT_SHOT:
333 return NULL;
334 }
335#elif defined(CONFIG_NET_CLS_POLICE)
336 if (result == TC_POLICE_SHOT)
337 return HTB_DIRECT;
338#endif
339 if ((cl = (void*)res.class) == NULL) {
340 if (res.classid == sch->handle)
341 return HTB_DIRECT; /* X:0 (direct flow) */
342 if ((cl = htb_find(res.classid,sch)) == NULL)
343 break; /* filter selected invalid classid */
344 }
345 if (!cl->level)
346 return cl; /* we hit leaf; return it */
347
348 /* we have got inner class; apply inner filter chain */
349 tcf = cl->filter_list;
350 }
351 /* classification failed; try to use default class */
352 cl = htb_find(TC_H_MAKE(TC_H_MAJ(sch->handle),q->defcls),sch);
353 if (!cl || cl->level)
354 return HTB_DIRECT; /* bad default .. this is safe bet */
355 return cl;
356}
357
358#ifdef HTB_DEBUG
359static void htb_next_rb_node(struct rb_node **n);
360#define HTB_DUMTREE(root,memb) if(root) { \
361 struct rb_node *n = (root)->rb_node; \
362 while (n->rb_left) n = n->rb_left; \
363 while (n) { \
364 struct htb_class *cl = rb_entry(n, struct htb_class, memb); \
365 printk(" %x",cl->classid); htb_next_rb_node (&n); \
366 } }
367
368static void htb_debug_dump (struct htb_sched *q)
369{
370 int i,p;
371 printk(KERN_DEBUG "htb*g j=%lu lj=%lu\n",jiffies,q->jiffies);
372 /* rows */
373 for (i=TC_HTB_MAXDEPTH-1;i>=0;i--) {
374 printk(KERN_DEBUG "htb*r%d m=%x",i,q->row_mask[i]);
375 for (p=0;p<TC_HTB_NUMPRIO;p++) {
376 if (!q->row[i][p].rb_node) continue;
377 printk(" p%d:",p);
378 HTB_DUMTREE(q->row[i]+p,node[p]);
379 }
380 printk("\n");
381 }
382 /* classes */
383 for (i = 0; i < HTB_HSIZE; i++) {
384 struct list_head *l;
385 list_for_each (l,q->hash+i) {
386 struct htb_class *cl = list_entry(l,struct htb_class,hlist);
387 long diff = PSCHED_TDIFF_SAFE(q->now, cl->t_c, (u32)cl->mbuffer);
388 printk(KERN_DEBUG "htb*c%x m=%d t=%ld c=%ld pq=%lu df=%ld ql=%d "
389 "pa=%x f:",
390 cl->classid,cl->cmode,cl->tokens,cl->ctokens,
391 cl->pq_node.rb_color==-1?0:cl->pq_key,diff,
392 cl->level?0:cl->un.leaf.q->q.qlen,cl->prio_activity);
393 if (cl->level)
394 for (p=0;p<TC_HTB_NUMPRIO;p++) {
395 if (!cl->un.inner.feed[p].rb_node) continue;
396 printk(" p%d a=%x:",p,cl->un.inner.ptr[p]?rb_entry(cl->un.inner.ptr[p], struct htb_class,node[p])->classid:0);
397 HTB_DUMTREE(cl->un.inner.feed+p,node[p]);
398 }
399 printk("\n");
400 }
401 }
402}
403#endif
404/**
405 * htb_add_to_id_tree - adds class to the round robin list
406 *
407 * Routine adds class to the list (actually tree) sorted by classid.
408 * Make sure that class is not already on such list for given prio.
409 */
410static void htb_add_to_id_tree (HTB_ARGQ struct rb_root *root,
411 struct htb_class *cl,int prio)
412{
413 struct rb_node **p = &root->rb_node, *parent = NULL;
414 HTB_DBG(7,3,"htb_add_id_tree cl=%X prio=%d\n",cl->classid,prio);
415#ifdef HTB_DEBUG
416 if (cl->node[prio].rb_color != -1) { BUG_TRAP(0); return; }
417 HTB_CHCL(cl);
418 if (*p) {
419 struct htb_class *x = rb_entry(*p,struct htb_class,node[prio]);
420 HTB_CHCL(x);
421 }
422#endif
423 while (*p) {
424 struct htb_class *c; parent = *p;
425 c = rb_entry(parent, struct htb_class, node[prio]);
426 HTB_CHCL(c);
427 if (cl->classid > c->classid)
428 p = &parent->rb_right;
429 else
430 p = &parent->rb_left;
431 }
432 rb_link_node(&cl->node[prio], parent, p);
433 rb_insert_color(&cl->node[prio], root);
434}
435
436/**
437 * htb_add_to_wait_tree - adds class to the event queue with delay
438 *
439 * The class is added to priority event queue to indicate that class will
440 * change its mode in cl->pq_key microseconds. Make sure that class is not
441 * already in the queue.
442 */
443static void htb_add_to_wait_tree (struct htb_sched *q,
444 struct htb_class *cl,long delay,int debug_hint)
445{
446 struct rb_node **p = &q->wait_pq[cl->level].rb_node, *parent = NULL;
447 HTB_DBG(7,3,"htb_add_wt cl=%X key=%lu\n",cl->classid,cl->pq_key);
448#ifdef HTB_DEBUG
449 if (cl->pq_node.rb_color != -1) { BUG_TRAP(0); return; }
450 HTB_CHCL(cl);
451 if ((delay <= 0 || delay > cl->mbuffer) && net_ratelimit())
452 printk(KERN_ERR "HTB: suspicious delay in wait_tree d=%ld cl=%X h=%d\n",delay,cl->classid,debug_hint);
453#endif
454 cl->pq_key = q->jiffies + PSCHED_US2JIFFIE(delay);
455 if (cl->pq_key == q->jiffies)
456 cl->pq_key++;
457
458 /* update the nearest event cache */
459 if (time_after(q->near_ev_cache[cl->level], cl->pq_key))
460 q->near_ev_cache[cl->level] = cl->pq_key;
461
462 while (*p) {
463 struct htb_class *c; parent = *p;
464 c = rb_entry(parent, struct htb_class, pq_node);
465 if (time_after_eq(cl->pq_key, c->pq_key))
466 p = &parent->rb_right;
467 else
468 p = &parent->rb_left;
469 }
470 rb_link_node(&cl->pq_node, parent, p);
471 rb_insert_color(&cl->pq_node, &q->wait_pq[cl->level]);
472}
473
474/**
475 * htb_next_rb_node - finds next node in binary tree
476 *
477 * When we are past last key we return NULL.
478 * Average complexity is 2 steps per call.
479 */
480static void htb_next_rb_node(struct rb_node **n)
481{
482 *n = rb_next(*n);
483}
484
485/**
486 * htb_add_class_to_row - add class to its row
487 *
488 * The class is added to row at priorities marked in mask.
489 * It does nothing if mask == 0.
490 */
491static inline void htb_add_class_to_row(struct htb_sched *q,
492 struct htb_class *cl,int mask)
493{
494 HTB_DBG(7,2,"htb_addrow cl=%X mask=%X rmask=%X\n",
495 cl->classid,mask,q->row_mask[cl->level]);
496 HTB_CHCL(cl);
497 q->row_mask[cl->level] |= mask;
498 while (mask) {
499 int prio = ffz(~mask);
500 mask &= ~(1 << prio);
501 htb_add_to_id_tree(HTB_PASSQ q->row[cl->level]+prio,cl,prio);
502 }
503}
504
505/**
506 * htb_remove_class_from_row - removes class from its row
507 *
508 * The class is removed from row at priorities marked in mask.
509 * It does nothing if mask == 0.
510 */
511static __inline__ void htb_remove_class_from_row(struct htb_sched *q,
512 struct htb_class *cl,int mask)
513{
514 int m = 0;
515 HTB_CHCL(cl);
516 while (mask) {
517 int prio = ffz(~mask);
518 mask &= ~(1 << prio);
519 if (q->ptr[cl->level][prio] == cl->node+prio)
520 htb_next_rb_node(q->ptr[cl->level]+prio);
521 htb_safe_rb_erase(cl->node + prio,q->row[cl->level]+prio);
522 if (!q->row[cl->level][prio].rb_node)
523 m |= 1 << prio;
524 }
525 HTB_DBG(7,2,"htb_delrow cl=%X mask=%X rmask=%X maskdel=%X\n",
526 cl->classid,mask,q->row_mask[cl->level],m);
527 q->row_mask[cl->level] &= ~m;
528}
529
530/**
531 * htb_activate_prios - creates active classe's feed chain
532 *
533 * The class is connected to ancestors and/or appropriate rows
534 * for priorities it is participating on. cl->cmode must be new
535 * (activated) mode. It does nothing if cl->prio_activity == 0.
536 */
537static void htb_activate_prios(struct htb_sched *q,struct htb_class *cl)
538{
539 struct htb_class *p = cl->parent;
540 long m,mask = cl->prio_activity;
541 HTB_DBG(7,2,"htb_act_prios cl=%X mask=%lX cmode=%d\n",cl->classid,mask,cl->cmode);
542 HTB_CHCL(cl);
543
544 while (cl->cmode == HTB_MAY_BORROW && p && mask) {
545 HTB_CHCL(p);
546 m = mask; while (m) {
547 int prio = ffz(~m);
548 m &= ~(1 << prio);
549
550 if (p->un.inner.feed[prio].rb_node)
551 /* parent already has its feed in use so that
552 reset bit in mask as parent is already ok */
553 mask &= ~(1 << prio);
554
555 htb_add_to_id_tree(HTB_PASSQ p->un.inner.feed+prio,cl,prio);
556 }
557 HTB_DBG(7,3,"htb_act_pr_aft p=%X pact=%X mask=%lX pmode=%d\n",
558 p->classid,p->prio_activity,mask,p->cmode);
559 p->prio_activity |= mask;
560 cl = p; p = cl->parent;
561 HTB_CHCL(cl);
562 }
563 if (cl->cmode == HTB_CAN_SEND && mask)
564 htb_add_class_to_row(q,cl,mask);
565}
566
567/**
568 * htb_deactivate_prios - remove class from feed chain
569 *
570 * cl->cmode must represent old mode (before deactivation). It does
571 * nothing if cl->prio_activity == 0. Class is removed from all feed
572 * chains and rows.
573 */
574static void htb_deactivate_prios(struct htb_sched *q, struct htb_class *cl)
575{
576 struct htb_class *p = cl->parent;
577 long m,mask = cl->prio_activity;
578 HTB_DBG(7,2,"htb_deact_prios cl=%X mask=%lX cmode=%d\n",cl->classid,mask,cl->cmode);
579 HTB_CHCL(cl);
580
581 while (cl->cmode == HTB_MAY_BORROW && p && mask) {
582 m = mask; mask = 0;
583 while (m) {
584 int prio = ffz(~m);
585 m &= ~(1 << prio);
586
587 if (p->un.inner.ptr[prio] == cl->node+prio) {
588 /* we are removing child which is pointed to from
589 parent feed - forget the pointer but remember
590 classid */
591 p->un.inner.last_ptr_id[prio] = cl->classid;
592 p->un.inner.ptr[prio] = NULL;
593 }
594
595 htb_safe_rb_erase(cl->node + prio,p->un.inner.feed + prio);
596
597 if (!p->un.inner.feed[prio].rb_node)
598 mask |= 1 << prio;
599 }
600 HTB_DBG(7,3,"htb_deact_pr_aft p=%X pact=%X mask=%lX pmode=%d\n",
601 p->classid,p->prio_activity,mask,p->cmode);
602 p->prio_activity &= ~mask;
603 cl = p; p = cl->parent;
604 HTB_CHCL(cl);
605 }
606 if (cl->cmode == HTB_CAN_SEND && mask)
607 htb_remove_class_from_row(q,cl,mask);
608}
609
610/**
611 * htb_class_mode - computes and returns current class mode
612 *
613 * It computes cl's mode at time cl->t_c+diff and returns it. If mode
614 * is not HTB_CAN_SEND then cl->pq_key is updated to time difference
615 * from now to time when cl will change its state.
616 * Also it is worth to note that class mode doesn't change simply
617 * at cl->{c,}tokens == 0 but there can rather be hysteresis of
618 * 0 .. -cl->{c,}buffer range. It is meant to limit number of
619 * mode transitions per time unit. The speed gain is about 1/6.
620 */
621static __inline__ enum htb_cmode
622htb_class_mode(struct htb_class *cl,long *diff)
623{
624 long toks;
625
626 if ((toks = (cl->ctokens + *diff)) < (
627#if HTB_HYSTERESIS
628 cl->cmode != HTB_CANT_SEND ? -cl->cbuffer :
629#endif
630 0)) {
631 *diff = -toks;
632 return HTB_CANT_SEND;
633 }
634 if ((toks = (cl->tokens + *diff)) >= (
635#if HTB_HYSTERESIS
636 cl->cmode == HTB_CAN_SEND ? -cl->buffer :
637#endif
638 0))
639 return HTB_CAN_SEND;
640
641 *diff = -toks;
642 return HTB_MAY_BORROW;
643}
644
645/**
646 * htb_change_class_mode - changes classe's mode
647 *
648 * This should be the only way how to change classe's mode under normal
649 * cirsumstances. Routine will update feed lists linkage, change mode
650 * and add class to the wait event queue if appropriate. New mode should
651 * be different from old one and cl->pq_key has to be valid if changing
652 * to mode other than HTB_CAN_SEND (see htb_add_to_wait_tree).
653 */
654static void
655htb_change_class_mode(struct htb_sched *q, struct htb_class *cl, long *diff)
656{
657 enum htb_cmode new_mode = htb_class_mode(cl,diff);
658
659 HTB_CHCL(cl);
660 HTB_DBG(7,1,"htb_chging_clmode %d->%d cl=%X\n",cl->cmode,new_mode,cl->classid);
661
662 if (new_mode == cl->cmode)
663 return;
664
665 if (cl->prio_activity) { /* not necessary: speed optimization */
666 if (cl->cmode != HTB_CANT_SEND)
667 htb_deactivate_prios(q,cl);
668 cl->cmode = new_mode;
669 if (new_mode != HTB_CANT_SEND)
670 htb_activate_prios(q,cl);
671 } else
672 cl->cmode = new_mode;
673}
674
675/**
676 * htb_activate - inserts leaf cl into appropriate active feeds
677 *
678 * Routine learns (new) priority of leaf and activates feed chain
679 * for the prio. It can be called on already active leaf safely.
680 * It also adds leaf into droplist.
681 */
682static __inline__ void htb_activate(struct htb_sched *q,struct htb_class *cl)
683{
684 BUG_TRAP(!cl->level && cl->un.leaf.q && cl->un.leaf.q->q.qlen);
685 HTB_CHCL(cl);
686 if (!cl->prio_activity) {
687 cl->prio_activity = 1 << (cl->un.leaf.aprio = cl->un.leaf.prio);
688 htb_activate_prios(q,cl);
689 list_add_tail(&cl->un.leaf.drop_list,q->drops+cl->un.leaf.aprio);
690 }
691}
692
693/**
694 * htb_deactivate - remove leaf cl from active feeds
695 *
696 * Make sure that leaf is active. In the other words it can't be called
697 * with non-active leaf. It also removes class from the drop list.
698 */
699static __inline__ void
700htb_deactivate(struct htb_sched *q,struct htb_class *cl)
701{
702 BUG_TRAP(cl->prio_activity);
703 HTB_CHCL(cl);
704 htb_deactivate_prios(q,cl);
705 cl->prio_activity = 0;
706 list_del_init(&cl->un.leaf.drop_list);
707}
708
709static int htb_enqueue(struct sk_buff *skb, struct Qdisc *sch)
710{
711 int ret;
712 struct htb_sched *q = qdisc_priv(sch);
713 struct htb_class *cl = htb_classify(skb,sch,&ret);
714
715 if (cl == HTB_DIRECT) {
716 /* enqueue to helper queue */
717 if (q->direct_queue.qlen < q->direct_qlen) {
718 __skb_queue_tail(&q->direct_queue, skb);
719 q->direct_pkts++;
Asim Shankar033d8992005-05-03 14:39:33 -0700720 } else {
721 kfree_skb(skb);
722 sch->qstats.drops++;
723 return NET_XMIT_DROP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724 }
725#ifdef CONFIG_NET_CLS_ACT
726 } else if (!cl) {
727 if (ret == NET_XMIT_DROP)
728 sch->qstats.drops++;
729 kfree_skb (skb);
730 return ret;
731#endif
732 } else if (cl->un.leaf.q->enqueue(skb, cl->un.leaf.q) != NET_XMIT_SUCCESS) {
733 sch->qstats.drops++;
734 cl->qstats.drops++;
735 return NET_XMIT_DROP;
736 } else {
737 cl->bstats.packets++; cl->bstats.bytes += skb->len;
738 htb_activate (q,cl);
739 }
740
741 sch->q.qlen++;
742 sch->bstats.packets++; sch->bstats.bytes += skb->len;
743 HTB_DBG(1,1,"htb_enq_ok cl=%X skb=%p\n",(cl && cl != HTB_DIRECT)?cl->classid:0,skb);
744 return NET_XMIT_SUCCESS;
745}
746
747/* TODO: requeuing packet charges it to policers again !! */
748static int htb_requeue(struct sk_buff *skb, struct Qdisc *sch)
749{
750 struct htb_sched *q = qdisc_priv(sch);
751 int ret = NET_XMIT_SUCCESS;
752 struct htb_class *cl = htb_classify(skb,sch, &ret);
753 struct sk_buff *tskb;
754
755 if (cl == HTB_DIRECT || !cl) {
756 /* enqueue to helper queue */
757 if (q->direct_queue.qlen < q->direct_qlen && cl) {
758 __skb_queue_head(&q->direct_queue, skb);
759 } else {
760 __skb_queue_head(&q->direct_queue, skb);
761 tskb = __skb_dequeue_tail(&q->direct_queue);
762 kfree_skb (tskb);
763 sch->qstats.drops++;
764 return NET_XMIT_CN;
765 }
766 } else if (cl->un.leaf.q->ops->requeue(skb, cl->un.leaf.q) != NET_XMIT_SUCCESS) {
767 sch->qstats.drops++;
768 cl->qstats.drops++;
769 return NET_XMIT_DROP;
770 } else
771 htb_activate (q,cl);
772
773 sch->q.qlen++;
774 sch->qstats.requeues++;
775 HTB_DBG(1,1,"htb_req_ok cl=%X skb=%p\n",(cl && cl != HTB_DIRECT)?cl->classid:0,skb);
776 return NET_XMIT_SUCCESS;
777}
778
779static void htb_timer(unsigned long arg)
780{
781 struct Qdisc *sch = (struct Qdisc*)arg;
782 sch->flags &= ~TCQ_F_THROTTLED;
783 wmb();
784 netif_schedule(sch->dev);
785}
786
787#ifdef HTB_RATECM
788#define RT_GEN(D,R) R+=D-(R/HTB_EWMAC);D=0
789static void htb_rate_timer(unsigned long arg)
790{
791 struct Qdisc *sch = (struct Qdisc*)arg;
792 struct htb_sched *q = qdisc_priv(sch);
793 struct list_head *p;
794
795 /* lock queue so that we can muck with it */
796 HTB_QLOCK(sch);
797 HTB_DBG(10,1,"htb_rttmr j=%ld\n",jiffies);
798
799 q->rttim.expires = jiffies + HZ;
800 add_timer(&q->rttim);
801
802 /* scan and recompute one bucket at time */
803 if (++q->recmp_bucket >= HTB_HSIZE)
804 q->recmp_bucket = 0;
805 list_for_each (p,q->hash+q->recmp_bucket) {
806 struct htb_class *cl = list_entry(p,struct htb_class,hlist);
807 HTB_DBG(10,2,"htb_rttmr_cl cl=%X sbyte=%lu spkt=%lu\n",
808 cl->classid,cl->sum_bytes,cl->sum_packets);
809 RT_GEN (cl->sum_bytes,cl->rate_bytes);
810 RT_GEN (cl->sum_packets,cl->rate_packets);
811 }
812 HTB_QUNLOCK(sch);
813}
814#endif
815
816/**
817 * htb_charge_class - charges amount "bytes" to leaf and ancestors
818 *
819 * Routine assumes that packet "bytes" long was dequeued from leaf cl
820 * borrowing from "level". It accounts bytes to ceil leaky bucket for
821 * leaf and all ancestors and to rate bucket for ancestors at levels
822 * "level" and higher. It also handles possible change of mode resulting
823 * from the update. Note that mode can also increase here (MAY_BORROW to
824 * CAN_SEND) because we can use more precise clock that event queue here.
825 * In such case we remove class from event queue first.
826 */
827static void htb_charge_class(struct htb_sched *q,struct htb_class *cl,
828 int level,int bytes)
829{
830 long toks,diff;
831 enum htb_cmode old_mode;
832 HTB_DBG(5,1,"htb_chrg_cl cl=%X lev=%d len=%d\n",cl->classid,level,bytes);
833
834#define HTB_ACCNT(T,B,R) toks = diff + cl->T; \
835 if (toks > cl->B) toks = cl->B; \
836 toks -= L2T(cl, cl->R, bytes); \
837 if (toks <= -cl->mbuffer) toks = 1-cl->mbuffer; \
838 cl->T = toks
839
840 while (cl) {
841 HTB_CHCL(cl);
842 diff = PSCHED_TDIFF_SAFE(q->now, cl->t_c, (u32)cl->mbuffer);
843#ifdef HTB_DEBUG
844 if (diff > cl->mbuffer || diff < 0 || PSCHED_TLESS(q->now, cl->t_c)) {
845 if (net_ratelimit())
846 printk(KERN_ERR "HTB: bad diff in charge, cl=%X diff=%lX now=%Lu then=%Lu j=%lu\n",
847 cl->classid, diff,
848#ifdef CONFIG_NET_SCH_CLK_GETTIMEOFDAY
849 q->now.tv_sec * 1000000ULL + q->now.tv_usec,
850 cl->t_c.tv_sec * 1000000ULL + cl->t_c.tv_usec,
851#else
852 (unsigned long long) q->now,
853 (unsigned long long) cl->t_c,
854#endif
855 q->jiffies);
856 diff = 1000;
857 }
858#endif
859 if (cl->level >= level) {
860 if (cl->level == level) cl->xstats.lends++;
861 HTB_ACCNT (tokens,buffer,rate);
862 } else {
863 cl->xstats.borrows++;
864 cl->tokens += diff; /* we moved t_c; update tokens */
865 }
866 HTB_ACCNT (ctokens,cbuffer,ceil);
867 cl->t_c = q->now;
868 HTB_DBG(5,2,"htb_chrg_clp cl=%X diff=%ld tok=%ld ctok=%ld\n",cl->classid,diff,cl->tokens,cl->ctokens);
869
870 old_mode = cl->cmode; diff = 0;
871 htb_change_class_mode(q,cl,&diff);
872 if (old_mode != cl->cmode) {
873 if (old_mode != HTB_CAN_SEND)
874 htb_safe_rb_erase(&cl->pq_node,q->wait_pq+cl->level);
875 if (cl->cmode != HTB_CAN_SEND)
876 htb_add_to_wait_tree (q,cl,diff,1);
877 }
878
879#ifdef HTB_RATECM
880 /* update rate counters */
881 cl->sum_bytes += bytes; cl->sum_packets++;
882#endif
883
884 /* update byte stats except for leaves which are already updated */
885 if (cl->level) {
886 cl->bstats.bytes += bytes;
887 cl->bstats.packets++;
888 }
889 cl = cl->parent;
890 }
891}
892
893/**
894 * htb_do_events - make mode changes to classes at the level
895 *
896 * Scans event queue for pending events and applies them. Returns jiffies to
897 * next pending event (0 for no event in pq).
898 * Note: Aplied are events whose have cl->pq_key <= jiffies.
899 */
900static long htb_do_events(struct htb_sched *q,int level)
901{
902 int i;
903 HTB_DBG(8,1,"htb_do_events l=%d root=%p rmask=%X\n",
904 level,q->wait_pq[level].rb_node,q->row_mask[level]);
905 for (i = 0; i < 500; i++) {
906 struct htb_class *cl;
907 long diff;
908 struct rb_node *p = q->wait_pq[level].rb_node;
909 if (!p) return 0;
910 while (p->rb_left) p = p->rb_left;
911
912 cl = rb_entry(p, struct htb_class, pq_node);
913 if (time_after(cl->pq_key, q->jiffies)) {
914 HTB_DBG(8,3,"htb_do_ev_ret delay=%ld\n",cl->pq_key - q->jiffies);
915 return cl->pq_key - q->jiffies;
916 }
917 htb_safe_rb_erase(p,q->wait_pq+level);
918 diff = PSCHED_TDIFF_SAFE(q->now, cl->t_c, (u32)cl->mbuffer);
919#ifdef HTB_DEBUG
920 if (diff > cl->mbuffer || diff < 0 || PSCHED_TLESS(q->now, cl->t_c)) {
921 if (net_ratelimit())
922 printk(KERN_ERR "HTB: bad diff in events, cl=%X diff=%lX now=%Lu then=%Lu j=%lu\n",
923 cl->classid, diff,
924#ifdef CONFIG_NET_SCH_CLK_GETTIMEOFDAY
925 q->now.tv_sec * 1000000ULL + q->now.tv_usec,
926 cl->t_c.tv_sec * 1000000ULL + cl->t_c.tv_usec,
927#else
928 (unsigned long long) q->now,
929 (unsigned long long) cl->t_c,
930#endif
931 q->jiffies);
932 diff = 1000;
933 }
934#endif
935 htb_change_class_mode(q,cl,&diff);
936 if (cl->cmode != HTB_CAN_SEND)
937 htb_add_to_wait_tree (q,cl,diff,2);
938 }
939 if (net_ratelimit())
940 printk(KERN_WARNING "htb: too many events !\n");
941 return HZ/10;
942}
943
944/* Returns class->node+prio from id-tree where classe's id is >= id. NULL
945 is no such one exists. */
946static struct rb_node *
947htb_id_find_next_upper(int prio,struct rb_node *n,u32 id)
948{
949 struct rb_node *r = NULL;
950 while (n) {
951 struct htb_class *cl = rb_entry(n,struct htb_class,node[prio]);
952 if (id == cl->classid) return n;
953
954 if (id > cl->classid) {
955 n = n->rb_right;
956 } else {
957 r = n;
958 n = n->rb_left;
959 }
960 }
961 return r;
962}
963
964/**
965 * htb_lookup_leaf - returns next leaf class in DRR order
966 *
967 * Find leaf where current feed pointers points to.
968 */
969static struct htb_class *
970htb_lookup_leaf(HTB_ARGQ struct rb_root *tree,int prio,struct rb_node **pptr,u32 *pid)
971{
972 int i;
973 struct {
974 struct rb_node *root;
975 struct rb_node **pptr;
976 u32 *pid;
977 } stk[TC_HTB_MAXDEPTH],*sp = stk;
978
979 BUG_TRAP(tree->rb_node);
980 sp->root = tree->rb_node;
981 sp->pptr = pptr;
982 sp->pid = pid;
983
984 for (i = 0; i < 65535; i++) {
985 HTB_DBG(4,2,"htb_lleaf ptr=%p pid=%X\n",*sp->pptr,*sp->pid);
986
987 if (!*sp->pptr && *sp->pid) {
988 /* ptr was invalidated but id is valid - try to recover
989 the original or next ptr */
990 *sp->pptr = htb_id_find_next_upper(prio,sp->root,*sp->pid);
991 }
992 *sp->pid = 0; /* ptr is valid now so that remove this hint as it
993 can become out of date quickly */
994 if (!*sp->pptr) { /* we are at right end; rewind & go up */
995 *sp->pptr = sp->root;
996 while ((*sp->pptr)->rb_left)
997 *sp->pptr = (*sp->pptr)->rb_left;
998 if (sp > stk) {
999 sp--;
1000 BUG_TRAP(*sp->pptr); if(!*sp->pptr) return NULL;
1001 htb_next_rb_node (sp->pptr);
1002 }
1003 } else {
1004 struct htb_class *cl;
1005 cl = rb_entry(*sp->pptr,struct htb_class,node[prio]);
1006 HTB_CHCL(cl);
1007 if (!cl->level)
1008 return cl;
1009 (++sp)->root = cl->un.inner.feed[prio].rb_node;
1010 sp->pptr = cl->un.inner.ptr+prio;
1011 sp->pid = cl->un.inner.last_ptr_id+prio;
1012 }
1013 }
1014 BUG_TRAP(0);
1015 return NULL;
1016}
1017
1018/* dequeues packet at given priority and level; call only if
1019 you are sure that there is active class at prio/level */
1020static struct sk_buff *
1021htb_dequeue_tree(struct htb_sched *q,int prio,int level)
1022{
1023 struct sk_buff *skb = NULL;
1024 struct htb_class *cl,*start;
1025 /* look initial class up in the row */
1026 start = cl = htb_lookup_leaf (HTB_PASSQ q->row[level]+prio,prio,
1027 q->ptr[level]+prio,q->last_ptr_id[level]+prio);
1028
1029 do {
1030next:
1031 BUG_TRAP(cl);
1032 if (!cl) return NULL;
1033 HTB_DBG(4,1,"htb_deq_tr prio=%d lev=%d cl=%X defic=%d\n",
1034 prio,level,cl->classid,cl->un.leaf.deficit[level]);
1035
1036 /* class can be empty - it is unlikely but can be true if leaf
1037 qdisc drops packets in enqueue routine or if someone used
1038 graft operation on the leaf since last dequeue;
1039 simply deactivate and skip such class */
1040 if (unlikely(cl->un.leaf.q->q.qlen == 0)) {
1041 struct htb_class *next;
1042 htb_deactivate(q,cl);
1043
1044 /* row/level might become empty */
1045 if ((q->row_mask[level] & (1 << prio)) == 0)
1046 return NULL;
1047
1048 next = htb_lookup_leaf (HTB_PASSQ q->row[level]+prio,
1049 prio,q->ptr[level]+prio,q->last_ptr_id[level]+prio);
1050
1051 if (cl == start) /* fix start if we just deleted it */
1052 start = next;
1053 cl = next;
1054 goto next;
1055 }
1056
1057 if (likely((skb = cl->un.leaf.q->dequeue(cl->un.leaf.q)) != NULL))
1058 break;
1059 if (!cl->warned) {
1060 printk(KERN_WARNING "htb: class %X isn't work conserving ?!\n",cl->classid);
1061 cl->warned = 1;
1062 }
1063 q->nwc_hit++;
1064 htb_next_rb_node((level?cl->parent->un.inner.ptr:q->ptr[0])+prio);
1065 cl = htb_lookup_leaf (HTB_PASSQ q->row[level]+prio,prio,q->ptr[level]+prio,
1066 q->last_ptr_id[level]+prio);
1067
1068 } while (cl != start);
1069
1070 if (likely(skb != NULL)) {
1071 if ((cl->un.leaf.deficit[level] -= skb->len) < 0) {
1072 HTB_DBG(4,2,"htb_next_cl oldptr=%p quant_add=%d\n",
1073 level?cl->parent->un.inner.ptr[prio]:q->ptr[0][prio],cl->un.leaf.quantum);
1074 cl->un.leaf.deficit[level] += cl->un.leaf.quantum;
1075 htb_next_rb_node((level?cl->parent->un.inner.ptr:q->ptr[0])+prio);
1076 }
1077 /* this used to be after charge_class but this constelation
1078 gives us slightly better performance */
1079 if (!cl->un.leaf.q->q.qlen)
1080 htb_deactivate (q,cl);
1081 htb_charge_class (q,cl,level,skb->len);
1082 }
1083 return skb;
1084}
1085
1086static void htb_delay_by(struct Qdisc *sch,long delay)
1087{
1088 struct htb_sched *q = qdisc_priv(sch);
1089 if (delay <= 0) delay = 1;
1090 if (unlikely(delay > 5*HZ)) {
1091 if (net_ratelimit())
1092 printk(KERN_INFO "HTB delay %ld > 5sec\n", delay);
1093 delay = 5*HZ;
1094 }
1095 /* why don't use jiffies here ? because expires can be in past */
1096 mod_timer(&q->timer, q->jiffies + delay);
1097 sch->flags |= TCQ_F_THROTTLED;
1098 sch->qstats.overlimits++;
1099 HTB_DBG(3,1,"htb_deq t_delay=%ld\n",delay);
1100}
1101
1102static struct sk_buff *htb_dequeue(struct Qdisc *sch)
1103{
1104 struct sk_buff *skb = NULL;
1105 struct htb_sched *q = qdisc_priv(sch);
1106 int level;
1107 long min_delay;
1108#ifdef HTB_DEBUG
1109 int evs_used = 0;
1110#endif
1111
1112 q->jiffies = jiffies;
1113 HTB_DBG(3,1,"htb_deq dircnt=%d qlen=%d\n",skb_queue_len(&q->direct_queue),
1114 sch->q.qlen);
1115
1116 /* try to dequeue direct packets as high prio (!) to minimize cpu work */
1117 if ((skb = __skb_dequeue(&q->direct_queue)) != NULL) {
1118 sch->flags &= ~TCQ_F_THROTTLED;
1119 sch->q.qlen--;
1120 return skb;
1121 }
1122
1123 if (!sch->q.qlen) goto fin;
1124 PSCHED_GET_TIME(q->now);
1125
1126 min_delay = LONG_MAX;
1127 q->nwc_hit = 0;
1128 for (level = 0; level < TC_HTB_MAXDEPTH; level++) {
1129 /* common case optimization - skip event handler quickly */
1130 int m;
1131 long delay;
1132 if (time_after_eq(q->jiffies, q->near_ev_cache[level])) {
1133 delay = htb_do_events(q,level);
1134 q->near_ev_cache[level] = q->jiffies + (delay ? delay : HZ);
1135#ifdef HTB_DEBUG
1136 evs_used++;
1137#endif
1138 } else
1139 delay = q->near_ev_cache[level] - q->jiffies;
1140
1141 if (delay && min_delay > delay)
1142 min_delay = delay;
1143 m = ~q->row_mask[level];
1144 while (m != (int)(-1)) {
1145 int prio = ffz (m);
1146 m |= 1 << prio;
1147 skb = htb_dequeue_tree(q,prio,level);
1148 if (likely(skb != NULL)) {
1149 sch->q.qlen--;
1150 sch->flags &= ~TCQ_F_THROTTLED;
1151 goto fin;
1152 }
1153 }
1154 }
1155#ifdef HTB_DEBUG
1156 if (!q->nwc_hit && min_delay >= 10*HZ && net_ratelimit()) {
1157 if (min_delay == LONG_MAX) {
1158 printk(KERN_ERR "HTB: dequeue bug (%d,%lu,%lu), report it please !\n",
1159 evs_used,q->jiffies,jiffies);
1160 htb_debug_dump(q);
1161 } else
1162 printk(KERN_WARNING "HTB: mindelay=%ld, some class has "
1163 "too small rate\n",min_delay);
1164 }
1165#endif
1166 htb_delay_by (sch,min_delay > 5*HZ ? 5*HZ : min_delay);
1167fin:
1168 HTB_DBG(3,1,"htb_deq_end %s j=%lu skb=%p\n",sch->dev->name,q->jiffies,skb);
1169 return skb;
1170}
1171
1172/* try to drop from each class (by prio) until one succeed */
1173static unsigned int htb_drop(struct Qdisc* sch)
1174{
1175 struct htb_sched *q = qdisc_priv(sch);
1176 int prio;
1177
1178 for (prio = TC_HTB_NUMPRIO - 1; prio >= 0; prio--) {
1179 struct list_head *p;
1180 list_for_each (p,q->drops+prio) {
1181 struct htb_class *cl = list_entry(p, struct htb_class,
1182 un.leaf.drop_list);
1183 unsigned int len;
1184 if (cl->un.leaf.q->ops->drop &&
1185 (len = cl->un.leaf.q->ops->drop(cl->un.leaf.q))) {
1186 sch->q.qlen--;
1187 if (!cl->un.leaf.q->q.qlen)
1188 htb_deactivate (q,cl);
1189 return len;
1190 }
1191 }
1192 }
1193 return 0;
1194}
1195
1196/* reset all classes */
1197/* always caled under BH & queue lock */
1198static void htb_reset(struct Qdisc* sch)
1199{
1200 struct htb_sched *q = qdisc_priv(sch);
1201 int i;
1202 HTB_DBG(0,1,"htb_reset sch=%p, handle=%X\n",sch,sch->handle);
1203
1204 for (i = 0; i < HTB_HSIZE; i++) {
1205 struct list_head *p;
1206 list_for_each (p,q->hash+i) {
1207 struct htb_class *cl = list_entry(p,struct htb_class,hlist);
1208 if (cl->level)
1209 memset(&cl->un.inner,0,sizeof(cl->un.inner));
1210 else {
1211 if (cl->un.leaf.q)
1212 qdisc_reset(cl->un.leaf.q);
1213 INIT_LIST_HEAD(&cl->un.leaf.drop_list);
1214 }
1215 cl->prio_activity = 0;
1216 cl->cmode = HTB_CAN_SEND;
1217#ifdef HTB_DEBUG
1218 cl->pq_node.rb_color = -1;
1219 memset(cl->node,255,sizeof(cl->node));
1220#endif
1221
1222 }
1223 }
1224 sch->flags &= ~TCQ_F_THROTTLED;
1225 del_timer(&q->timer);
1226 __skb_queue_purge(&q->direct_queue);
1227 sch->q.qlen = 0;
1228 memset(q->row,0,sizeof(q->row));
1229 memset(q->row_mask,0,sizeof(q->row_mask));
1230 memset(q->wait_pq,0,sizeof(q->wait_pq));
1231 memset(q->ptr,0,sizeof(q->ptr));
1232 for (i = 0; i < TC_HTB_NUMPRIO; i++)
1233 INIT_LIST_HEAD(q->drops+i);
1234}
1235
1236static int htb_init(struct Qdisc *sch, struct rtattr *opt)
1237{
1238 struct htb_sched *q = qdisc_priv(sch);
1239 struct rtattr *tb[TCA_HTB_INIT];
1240 struct tc_htb_glob *gopt;
1241 int i;
1242#ifdef HTB_DEBUG
1243 printk(KERN_INFO "HTB init, kernel part version %d.%d\n",
1244 HTB_VER >> 16,HTB_VER & 0xffff);
1245#endif
1246 if (!opt || rtattr_parse_nested(tb, TCA_HTB_INIT, opt) ||
1247 tb[TCA_HTB_INIT-1] == NULL ||
1248 RTA_PAYLOAD(tb[TCA_HTB_INIT-1]) < sizeof(*gopt)) {
1249 printk(KERN_ERR "HTB: hey probably you have bad tc tool ?\n");
1250 return -EINVAL;
1251 }
1252 gopt = RTA_DATA(tb[TCA_HTB_INIT-1]);
1253 if (gopt->version != HTB_VER >> 16) {
1254 printk(KERN_ERR "HTB: need tc/htb version %d (minor is %d), you have %d\n",
1255 HTB_VER >> 16,HTB_VER & 0xffff,gopt->version);
1256 return -EINVAL;
1257 }
1258 q->debug = gopt->debug;
1259 HTB_DBG(0,1,"htb_init sch=%p handle=%X r2q=%d\n",sch,sch->handle,gopt->rate2quantum);
1260
1261 INIT_LIST_HEAD(&q->root);
1262 for (i = 0; i < HTB_HSIZE; i++)
1263 INIT_LIST_HEAD(q->hash+i);
1264 for (i = 0; i < TC_HTB_NUMPRIO; i++)
1265 INIT_LIST_HEAD(q->drops+i);
1266
1267 init_timer(&q->timer);
1268 skb_queue_head_init(&q->direct_queue);
1269
1270 q->direct_qlen = sch->dev->tx_queue_len;
1271 if (q->direct_qlen < 2) /* some devices have zero tx_queue_len */
1272 q->direct_qlen = 2;
1273 q->timer.function = htb_timer;
1274 q->timer.data = (unsigned long)sch;
1275
1276#ifdef HTB_RATECM
1277 init_timer(&q->rttim);
1278 q->rttim.function = htb_rate_timer;
1279 q->rttim.data = (unsigned long)sch;
1280 q->rttim.expires = jiffies + HZ;
1281 add_timer(&q->rttim);
1282#endif
1283 if ((q->rate2quantum = gopt->rate2quantum) < 1)
1284 q->rate2quantum = 1;
1285 q->defcls = gopt->defcls;
1286
1287 return 0;
1288}
1289
1290static int htb_dump(struct Qdisc *sch, struct sk_buff *skb)
1291{
1292 struct htb_sched *q = qdisc_priv(sch);
1293 unsigned char *b = skb->tail;
1294 struct rtattr *rta;
1295 struct tc_htb_glob gopt;
1296 HTB_DBG(0,1,"htb_dump sch=%p, handle=%X\n",sch,sch->handle);
1297 HTB_QLOCK(sch);
1298 gopt.direct_pkts = q->direct_pkts;
1299
1300#ifdef HTB_DEBUG
1301 if (HTB_DBG_COND(0,2))
1302 htb_debug_dump(q);
1303#endif
1304 gopt.version = HTB_VER;
1305 gopt.rate2quantum = q->rate2quantum;
1306 gopt.defcls = q->defcls;
1307 gopt.debug = q->debug;
1308 rta = (struct rtattr*)b;
1309 RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
1310 RTA_PUT(skb, TCA_HTB_INIT, sizeof(gopt), &gopt);
1311 rta->rta_len = skb->tail - b;
1312 HTB_QUNLOCK(sch);
1313 return skb->len;
1314rtattr_failure:
1315 HTB_QUNLOCK(sch);
1316 skb_trim(skb, skb->tail - skb->data);
1317 return -1;
1318}
1319
1320static int htb_dump_class(struct Qdisc *sch, unsigned long arg,
1321 struct sk_buff *skb, struct tcmsg *tcm)
1322{
1323#ifdef HTB_DEBUG
1324 struct htb_sched *q = qdisc_priv(sch);
1325#endif
1326 struct htb_class *cl = (struct htb_class*)arg;
1327 unsigned char *b = skb->tail;
1328 struct rtattr *rta;
1329 struct tc_htb_opt opt;
1330
1331 HTB_DBG(0,1,"htb_dump_class handle=%X clid=%X\n",sch->handle,cl->classid);
1332
1333 HTB_QLOCK(sch);
1334 tcm->tcm_parent = cl->parent ? cl->parent->classid : TC_H_ROOT;
1335 tcm->tcm_handle = cl->classid;
1336 if (!cl->level && cl->un.leaf.q)
1337 tcm->tcm_info = cl->un.leaf.q->handle;
1338
1339 rta = (struct rtattr*)b;
1340 RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
1341
1342 memset (&opt,0,sizeof(opt));
1343
1344 opt.rate = cl->rate->rate; opt.buffer = cl->buffer;
1345 opt.ceil = cl->ceil->rate; opt.cbuffer = cl->cbuffer;
1346 opt.quantum = cl->un.leaf.quantum; opt.prio = cl->un.leaf.prio;
1347 opt.level = cl->level;
1348 RTA_PUT(skb, TCA_HTB_PARMS, sizeof(opt), &opt);
1349 rta->rta_len = skb->tail - b;
1350 HTB_QUNLOCK(sch);
1351 return skb->len;
1352rtattr_failure:
1353 HTB_QUNLOCK(sch);
1354 skb_trim(skb, b - skb->data);
1355 return -1;
1356}
1357
1358static int
1359htb_dump_class_stats(struct Qdisc *sch, unsigned long arg,
1360 struct gnet_dump *d)
1361{
1362 struct htb_class *cl = (struct htb_class*)arg;
1363
1364#ifdef HTB_RATECM
1365 cl->rate_est.bps = cl->rate_bytes/(HTB_EWMAC*HTB_HSIZE);
1366 cl->rate_est.pps = cl->rate_packets/(HTB_EWMAC*HTB_HSIZE);
1367#endif
1368
1369 if (!cl->level && cl->un.leaf.q)
1370 cl->qstats.qlen = cl->un.leaf.q->q.qlen;
1371 cl->xstats.tokens = cl->tokens;
1372 cl->xstats.ctokens = cl->ctokens;
1373
1374 if (gnet_stats_copy_basic(d, &cl->bstats) < 0 ||
1375 gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 ||
1376 gnet_stats_copy_queue(d, &cl->qstats) < 0)
1377 return -1;
1378
1379 return gnet_stats_copy_app(d, &cl->xstats, sizeof(cl->xstats));
1380}
1381
1382static int htb_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
1383 struct Qdisc **old)
1384{
1385 struct htb_class *cl = (struct htb_class*)arg;
1386
1387 if (cl && !cl->level) {
1388 if (new == NULL && (new = qdisc_create_dflt(sch->dev,
1389 &pfifo_qdisc_ops)) == NULL)
1390 return -ENOBUFS;
1391 sch_tree_lock(sch);
1392 if ((*old = xchg(&cl->un.leaf.q, new)) != NULL) {
1393 if (cl->prio_activity)
1394 htb_deactivate (qdisc_priv(sch),cl);
1395
1396 /* TODO: is it correct ? Why CBQ doesn't do it ? */
1397 sch->q.qlen -= (*old)->q.qlen;
1398 qdisc_reset(*old);
1399 }
1400 sch_tree_unlock(sch);
1401 return 0;
1402 }
1403 return -ENOENT;
1404}
1405
1406static struct Qdisc * htb_leaf(struct Qdisc *sch, unsigned long arg)
1407{
1408 struct htb_class *cl = (struct htb_class*)arg;
1409 return (cl && !cl->level) ? cl->un.leaf.q : NULL;
1410}
1411
1412static unsigned long htb_get(struct Qdisc *sch, u32 classid)
1413{
1414#ifdef HTB_DEBUG
1415 struct htb_sched *q = qdisc_priv(sch);
1416#endif
1417 struct htb_class *cl = htb_find(classid,sch);
1418 HTB_DBG(0,1,"htb_get clid=%X q=%p cl=%p ref=%d\n",classid,q,cl,cl?cl->refcnt:0);
1419 if (cl)
1420 cl->refcnt++;
1421 return (unsigned long)cl;
1422}
1423
1424static void htb_destroy_filters(struct tcf_proto **fl)
1425{
1426 struct tcf_proto *tp;
1427
1428 while ((tp = *fl) != NULL) {
1429 *fl = tp->next;
1430 tcf_destroy(tp);
1431 }
1432}
1433
1434static void htb_destroy_class(struct Qdisc* sch,struct htb_class *cl)
1435{
1436 struct htb_sched *q = qdisc_priv(sch);
1437 HTB_DBG(0,1,"htb_destrycls clid=%X ref=%d\n", cl?cl->classid:0,cl?cl->refcnt:0);
1438 if (!cl->level) {
1439 BUG_TRAP(cl->un.leaf.q);
1440 sch->q.qlen -= cl->un.leaf.q->q.qlen;
1441 qdisc_destroy(cl->un.leaf.q);
1442 }
1443 qdisc_put_rtab(cl->rate);
1444 qdisc_put_rtab(cl->ceil);
1445
1446 htb_destroy_filters (&cl->filter_list);
1447
1448 while (!list_empty(&cl->children))
1449 htb_destroy_class (sch,list_entry(cl->children.next,
1450 struct htb_class,sibling));
1451
1452 /* note: this delete may happen twice (see htb_delete) */
1453 list_del(&cl->hlist);
1454 list_del(&cl->sibling);
1455
1456 if (cl->prio_activity)
1457 htb_deactivate (q,cl);
1458
1459 if (cl->cmode != HTB_CAN_SEND)
1460 htb_safe_rb_erase(&cl->pq_node,q->wait_pq+cl->level);
1461
1462 kfree(cl);
1463}
1464
1465/* always caled under BH & queue lock */
1466static void htb_destroy(struct Qdisc* sch)
1467{
1468 struct htb_sched *q = qdisc_priv(sch);
1469 HTB_DBG(0,1,"htb_destroy q=%p\n",q);
1470
1471 del_timer_sync (&q->timer);
1472#ifdef HTB_RATECM
1473 del_timer_sync (&q->rttim);
1474#endif
1475 /* This line used to be after htb_destroy_class call below
1476 and surprisingly it worked in 2.4. But it must precede it
1477 because filter need its target class alive to be able to call
1478 unbind_filter on it (without Oops). */
1479 htb_destroy_filters(&q->filter_list);
1480
1481 while (!list_empty(&q->root))
1482 htb_destroy_class (sch,list_entry(q->root.next,
1483 struct htb_class,sibling));
1484
1485 __skb_queue_purge(&q->direct_queue);
1486}
1487
1488static int htb_delete(struct Qdisc *sch, unsigned long arg)
1489{
1490 struct htb_sched *q = qdisc_priv(sch);
1491 struct htb_class *cl = (struct htb_class*)arg;
1492 HTB_DBG(0,1,"htb_delete q=%p cl=%X ref=%d\n",q,cl?cl->classid:0,cl?cl->refcnt:0);
1493
1494 // TODO: why don't allow to delete subtree ? references ? does
1495 // tc subsys quarantee us that in htb_destroy it holds no class
1496 // refs so that we can remove children safely there ?
1497 if (!list_empty(&cl->children) || cl->filter_cnt)
1498 return -EBUSY;
1499
1500 sch_tree_lock(sch);
1501
1502 /* delete from hash and active; remainder in destroy_class */
1503 list_del_init(&cl->hlist);
1504 if (cl->prio_activity)
1505 htb_deactivate (q,cl);
1506
1507 if (--cl->refcnt == 0)
1508 htb_destroy_class(sch,cl);
1509
1510 sch_tree_unlock(sch);
1511 return 0;
1512}
1513
1514static void htb_put(struct Qdisc *sch, unsigned long arg)
1515{
1516#ifdef HTB_DEBUG
1517 struct htb_sched *q = qdisc_priv(sch);
1518#endif
1519 struct htb_class *cl = (struct htb_class*)arg;
1520 HTB_DBG(0,1,"htb_put q=%p cl=%X ref=%d\n",q,cl?cl->classid:0,cl?cl->refcnt:0);
1521
1522 if (--cl->refcnt == 0)
1523 htb_destroy_class(sch,cl);
1524}
1525
1526static int htb_change_class(struct Qdisc *sch, u32 classid,
1527 u32 parentid, struct rtattr **tca, unsigned long *arg)
1528{
1529 int err = -EINVAL;
1530 struct htb_sched *q = qdisc_priv(sch);
1531 struct htb_class *cl = (struct htb_class*)*arg,*parent;
1532 struct rtattr *opt = tca[TCA_OPTIONS-1];
1533 struct qdisc_rate_table *rtab = NULL, *ctab = NULL;
1534 struct rtattr *tb[TCA_HTB_RTAB];
1535 struct tc_htb_opt *hopt;
1536
1537 /* extract all subattrs from opt attr */
1538 if (!opt || rtattr_parse_nested(tb, TCA_HTB_RTAB, opt) ||
1539 tb[TCA_HTB_PARMS-1] == NULL ||
1540 RTA_PAYLOAD(tb[TCA_HTB_PARMS-1]) < sizeof(*hopt))
1541 goto failure;
1542
1543 parent = parentid == TC_H_ROOT ? NULL : htb_find (parentid,sch);
1544
1545 hopt = RTA_DATA(tb[TCA_HTB_PARMS-1]);
1546 HTB_DBG(0,1,"htb_chg cl=%p(%X), clid=%X, parid=%X, opt/prio=%d, rate=%u, buff=%d, quant=%d\n", cl,cl?cl->classid:0,classid,parentid,(int)hopt->prio,hopt->rate.rate,hopt->buffer,hopt->quantum);
1547 rtab = qdisc_get_rtab(&hopt->rate, tb[TCA_HTB_RTAB-1]);
1548 ctab = qdisc_get_rtab(&hopt->ceil, tb[TCA_HTB_CTAB-1]);
1549 if (!rtab || !ctab) goto failure;
1550
1551 if (!cl) { /* new class */
1552 struct Qdisc *new_q;
1553 /* check for valid classid */
1554 if (!classid || TC_H_MAJ(classid^sch->handle) || htb_find(classid,sch))
1555 goto failure;
1556
1557 /* check maximal depth */
1558 if (parent && parent->parent && parent->parent->level < 2) {
1559 printk(KERN_ERR "htb: tree is too deep\n");
1560 goto failure;
1561 }
1562 err = -ENOBUFS;
1563 if ((cl = kmalloc(sizeof(*cl), GFP_KERNEL)) == NULL)
1564 goto failure;
1565
1566 memset(cl, 0, sizeof(*cl));
1567 cl->refcnt = 1;
1568 INIT_LIST_HEAD(&cl->sibling);
1569 INIT_LIST_HEAD(&cl->hlist);
1570 INIT_LIST_HEAD(&cl->children);
1571 INIT_LIST_HEAD(&cl->un.leaf.drop_list);
1572#ifdef HTB_DEBUG
1573 cl->magic = HTB_CMAGIC;
1574#endif
1575
1576 /* create leaf qdisc early because it uses kmalloc(GFP_KERNEL)
1577 so that can't be used inside of sch_tree_lock
1578 -- thanks to Karlis Peisenieks */
1579 new_q = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops);
1580 sch_tree_lock(sch);
1581 if (parent && !parent->level) {
1582 /* turn parent into inner node */
1583 sch->q.qlen -= parent->un.leaf.q->q.qlen;
1584 qdisc_destroy (parent->un.leaf.q);
1585 if (parent->prio_activity)
1586 htb_deactivate (q,parent);
1587
1588 /* remove from evt list because of level change */
1589 if (parent->cmode != HTB_CAN_SEND) {
1590 htb_safe_rb_erase(&parent->pq_node,q->wait_pq /*+0*/);
1591 parent->cmode = HTB_CAN_SEND;
1592 }
1593 parent->level = (parent->parent ? parent->parent->level
1594 : TC_HTB_MAXDEPTH) - 1;
1595 memset (&parent->un.inner,0,sizeof(parent->un.inner));
1596 }
1597 /* leaf (we) needs elementary qdisc */
1598 cl->un.leaf.q = new_q ? new_q : &noop_qdisc;
1599
1600 cl->classid = classid; cl->parent = parent;
1601
1602 /* set class to be in HTB_CAN_SEND state */
1603 cl->tokens = hopt->buffer;
1604 cl->ctokens = hopt->cbuffer;
1605 cl->mbuffer = 60000000; /* 1min */
1606 PSCHED_GET_TIME(cl->t_c);
1607 cl->cmode = HTB_CAN_SEND;
1608
1609 /* attach to the hash list and parent's family */
1610 list_add_tail(&cl->hlist, q->hash+htb_hash(classid));
1611 list_add_tail(&cl->sibling, parent ? &parent->children : &q->root);
1612#ifdef HTB_DEBUG
1613 {
1614 int i;
1615 for (i = 0; i < TC_HTB_NUMPRIO; i++) cl->node[i].rb_color = -1;
1616 cl->pq_node.rb_color = -1;
1617 }
1618#endif
1619 } else sch_tree_lock(sch);
1620
1621 /* it used to be a nasty bug here, we have to check that node
1622 is really leaf before changing cl->un.leaf ! */
1623 if (!cl->level) {
1624 cl->un.leaf.quantum = rtab->rate.rate / q->rate2quantum;
1625 if (!hopt->quantum && cl->un.leaf.quantum < 1000) {
1626 printk(KERN_WARNING "HTB: quantum of class %X is small. Consider r2q change.\n", cl->classid);
1627 cl->un.leaf.quantum = 1000;
1628 }
1629 if (!hopt->quantum && cl->un.leaf.quantum > 200000) {
1630 printk(KERN_WARNING "HTB: quantum of class %X is big. Consider r2q change.\n", cl->classid);
1631 cl->un.leaf.quantum = 200000;
1632 }
1633 if (hopt->quantum)
1634 cl->un.leaf.quantum = hopt->quantum;
1635 if ((cl->un.leaf.prio = hopt->prio) >= TC_HTB_NUMPRIO)
1636 cl->un.leaf.prio = TC_HTB_NUMPRIO - 1;
1637 }
1638
1639 cl->buffer = hopt->buffer;
1640 cl->cbuffer = hopt->cbuffer;
1641 if (cl->rate) qdisc_put_rtab(cl->rate); cl->rate = rtab;
1642 if (cl->ceil) qdisc_put_rtab(cl->ceil); cl->ceil = ctab;
1643 sch_tree_unlock(sch);
1644
1645 *arg = (unsigned long)cl;
1646 return 0;
1647
1648failure:
1649 if (rtab) qdisc_put_rtab(rtab);
1650 if (ctab) qdisc_put_rtab(ctab);
1651 return err;
1652}
1653
1654static struct tcf_proto **htb_find_tcf(struct Qdisc *sch, unsigned long arg)
1655{
1656 struct htb_sched *q = qdisc_priv(sch);
1657 struct htb_class *cl = (struct htb_class *)arg;
1658 struct tcf_proto **fl = cl ? &cl->filter_list : &q->filter_list;
1659 HTB_DBG(0,2,"htb_tcf q=%p clid=%X fref=%d fl=%p\n",q,cl?cl->classid:0,cl?cl->filter_cnt:q->filter_cnt,*fl);
1660 return fl;
1661}
1662
1663static unsigned long htb_bind_filter(struct Qdisc *sch, unsigned long parent,
1664 u32 classid)
1665{
1666 struct htb_sched *q = qdisc_priv(sch);
1667 struct htb_class *cl = htb_find (classid,sch);
1668 HTB_DBG(0,2,"htb_bind q=%p clid=%X cl=%p fref=%d\n",q,classid,cl,cl?cl->filter_cnt:q->filter_cnt);
1669 /*if (cl && !cl->level) return 0;
1670 The line above used to be there to prevent attaching filters to
1671 leaves. But at least tc_index filter uses this just to get class
1672 for other reasons so that we have to allow for it.
1673 ----
1674 19.6.2002 As Werner explained it is ok - bind filter is just
1675 another way to "lock" the class - unlike "get" this lock can
1676 be broken by class during destroy IIUC.
1677 */
1678 if (cl)
1679 cl->filter_cnt++;
1680 else
1681 q->filter_cnt++;
1682 return (unsigned long)cl;
1683}
1684
1685static void htb_unbind_filter(struct Qdisc *sch, unsigned long arg)
1686{
1687 struct htb_sched *q = qdisc_priv(sch);
1688 struct htb_class *cl = (struct htb_class *)arg;
1689 HTB_DBG(0,2,"htb_unbind q=%p cl=%p fref=%d\n",q,cl,cl?cl->filter_cnt:q->filter_cnt);
1690 if (cl)
1691 cl->filter_cnt--;
1692 else
1693 q->filter_cnt--;
1694}
1695
1696static void htb_walk(struct Qdisc *sch, struct qdisc_walker *arg)
1697{
1698 struct htb_sched *q = qdisc_priv(sch);
1699 int i;
1700
1701 if (arg->stop)
1702 return;
1703
1704 for (i = 0; i < HTB_HSIZE; i++) {
1705 struct list_head *p;
1706 list_for_each (p,q->hash+i) {
1707 struct htb_class *cl = list_entry(p,struct htb_class,hlist);
1708 if (arg->count < arg->skip) {
1709 arg->count++;
1710 continue;
1711 }
1712 if (arg->fn(sch, (unsigned long)cl, arg) < 0) {
1713 arg->stop = 1;
1714 return;
1715 }
1716 arg->count++;
1717 }
1718 }
1719}
1720
1721static struct Qdisc_class_ops htb_class_ops = {
1722 .graft = htb_graft,
1723 .leaf = htb_leaf,
1724 .get = htb_get,
1725 .put = htb_put,
1726 .change = htb_change_class,
1727 .delete = htb_delete,
1728 .walk = htb_walk,
1729 .tcf_chain = htb_find_tcf,
1730 .bind_tcf = htb_bind_filter,
1731 .unbind_tcf = htb_unbind_filter,
1732 .dump = htb_dump_class,
1733 .dump_stats = htb_dump_class_stats,
1734};
1735
1736static struct Qdisc_ops htb_qdisc_ops = {
1737 .next = NULL,
1738 .cl_ops = &htb_class_ops,
1739 .id = "htb",
1740 .priv_size = sizeof(struct htb_sched),
1741 .enqueue = htb_enqueue,
1742 .dequeue = htb_dequeue,
1743 .requeue = htb_requeue,
1744 .drop = htb_drop,
1745 .init = htb_init,
1746 .reset = htb_reset,
1747 .destroy = htb_destroy,
1748 .change = NULL /* htb_change */,
1749 .dump = htb_dump,
1750 .owner = THIS_MODULE,
1751};
1752
1753static int __init htb_module_init(void)
1754{
1755 return register_qdisc(&htb_qdisc_ops);
1756}
1757static void __exit htb_module_exit(void)
1758{
1759 unregister_qdisc(&htb_qdisc_ops);
1760}
1761module_init(htb_module_init)
1762module_exit(htb_module_exit)
1763MODULE_LICENSE("GPL");