2 * net/sched/sch_htb.c Hierarchical token bucket, feed tree version
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.
9 * Authors: Martin Devera, <devik@cdi.cz>
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
23 * spotted bug in dequeue code and helped with fix
25 * fixed requeue routine
26 * and many others. thanks.
28 * $Id: sch_htb.c,v 1.25 2003/12/07 11:08:25 devik Exp devik $
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>
39 #include <linux/socket.h>
40 #include <linux/sockios.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>
50 #include <net/route.h>
51 #include <linux/skbuff.h>
52 #include <linux/list.h>
53 #include <linux/compiler.h>
55 #include <net/pkt_sched.h>
56 #include <linux/rbtree.h>
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.
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.
71 #define HTB_HSIZE 16 /* classid hash size */
72 #define HTB_EWMAC 2 /* rate average over HTB_EWMAC*HTB_HSIZE sec */
73 #define HTB_RATECM 1 /* whether to use rate computer */
74 #define HTB_HYSTERESIS 1 /* whether to use mode hysteresis for speedup */
75 #define HTB_VER 0x30011 /* major must be matched with number suplied by TC as version */
77 #if HTB_VER >> 16 != TC_HTB_PROTOVER
78 #error "Mismatched sch_htb.c and pkt_sch.h"
81 /* used internaly to keep status of single class */
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 */
88 /* interior & leaf nodes; props specific to leaves are marked L: */
90 /* general class parameters */
92 struct gnet_stats_basic bstats
;
93 struct gnet_stats_queue qstats
;
94 struct gnet_stats_rate_est rate_est
;
95 struct tc_htb_xstats xstats
; /* our special stats */
96 int refcnt
; /* usage count of this class */
99 /* rate measurement counters */
100 unsigned long rate_bytes
, sum_bytes
;
101 unsigned long rate_packets
, sum_packets
;
105 int level
; /* our level (see above) */
106 struct htb_class
*parent
; /* parent class */
107 struct hlist_node hlist
; /* classid hash list item */
108 struct list_head sibling
; /* sibling list item */
109 struct list_head children
; /* children list */
112 struct htb_class_leaf
{
117 int deficit
[TC_HTB_MAXDEPTH
];
118 struct list_head drop_list
;
120 struct htb_class_inner
{
121 struct rb_root feed
[TC_HTB_NUMPRIO
]; /* feed trees */
122 struct rb_node
*ptr
[TC_HTB_NUMPRIO
]; /* current class ptr */
123 /* When class changes from state 1->2 and disconnects from
124 parent's feed then we lost ptr value and start from the
125 first child again. Here we store classid of the
126 last valid ptr (used when ptr is NULL). */
127 u32 last_ptr_id
[TC_HTB_NUMPRIO
];
130 struct rb_node node
[TC_HTB_NUMPRIO
]; /* node for self or feed tree */
131 struct rb_node pq_node
; /* node for event queue */
132 unsigned long pq_key
; /* the same type as jiffies global */
134 int prio_activity
; /* for which prios are we active */
135 enum htb_cmode cmode
; /* current mode of the class */
137 /* class attached filters */
138 struct tcf_proto
*filter_list
;
141 int warned
; /* only one warning about non work conserving .. */
143 /* token bucket parameters */
144 struct qdisc_rate_table
*rate
; /* rate table of the class itself */
145 struct qdisc_rate_table
*ceil
; /* ceiling rate (limits borrows too) */
146 long buffer
, cbuffer
; /* token bucket depth/rate */
147 psched_tdiff_t mbuffer
; /* max wait time */
148 long tokens
, ctokens
; /* current number of tokens */
149 psched_time_t t_c
; /* checkpoint time */
152 /* TODO: maybe compute rate when size is too large .. or drop ? */
153 static inline long L2T(struct htb_class
*cl
, struct qdisc_rate_table
*rate
,
156 int slot
= size
>> rate
->rate
.cell_log
;
161 return rate
->data
[slot
];
165 struct list_head root
; /* root classes list */
166 struct hlist_head hash
[HTB_HSIZE
]; /* hashed by classid */
167 struct list_head drops
[TC_HTB_NUMPRIO
];/* active leaves (for drops) */
169 /* self list - roots of self generating tree */
170 struct rb_root row
[TC_HTB_MAXDEPTH
][TC_HTB_NUMPRIO
];
171 int row_mask
[TC_HTB_MAXDEPTH
];
172 struct rb_node
*ptr
[TC_HTB_MAXDEPTH
][TC_HTB_NUMPRIO
];
173 u32 last_ptr_id
[TC_HTB_MAXDEPTH
][TC_HTB_NUMPRIO
];
175 /* self wait list - roots of wait PQs per row */
176 struct rb_root wait_pq
[TC_HTB_MAXDEPTH
];
178 /* time of nearest event per level (row) */
179 unsigned long near_ev_cache
[TC_HTB_MAXDEPTH
];
181 /* cached value of jiffies in dequeue */
182 unsigned long jiffies
;
184 /* whether we hit non-work conserving class during this dequeue; we use */
185 int nwc_hit
; /* this to disable mindelay complaint in dequeue */
187 int defcls
; /* class where unclassified flows go to */
189 /* filters for qdisc itself */
190 struct tcf_proto
*filter_list
;
193 int rate2quantum
; /* quant = rate / rate2quantum */
194 psched_time_t now
; /* cached dequeue time */
195 struct timer_list timer
; /* send delay timer */
197 struct timer_list rttim
; /* rate computer timer */
198 int recmp_bucket
; /* which hash bucket to recompute next */
201 /* non shaped skbs; let them go directly thru */
202 struct sk_buff_head direct_queue
;
203 int direct_qlen
; /* max qlen of above */
208 /* compute hash of size HTB_HSIZE for given handle */
209 static inline int htb_hash(u32 h
)
212 #error "Declare new hash for your HTB_HSIZE"
214 h
^= h
>> 8; /* stolen from cbq_hash */
219 /* find class in global hash table using given handle */
220 static inline struct htb_class
*htb_find(u32 handle
, struct Qdisc
*sch
)
222 struct htb_sched
*q
= qdisc_priv(sch
);
223 struct hlist_node
*p
;
224 struct htb_class
*cl
;
226 if (TC_H_MAJ(handle
) != sch
->handle
)
229 hlist_for_each_entry(cl
, p
, q
->hash
+ htb_hash(handle
), hlist
) {
230 if (cl
->classid
== handle
)
237 * htb_classify - classify a packet into class
239 * It returns NULL if the packet should be dropped or -1 if the packet
240 * should be passed directly thru. In all other cases leaf class is returned.
241 * We allow direct class selection by classid in priority. The we examine
242 * filters in qdisc and in inner nodes (if higher filter points to the inner
243 * node). If we end up with classid MAJOR:0 we enqueue the skb into special
244 * internal fifo (direct). These packets then go directly thru. If we still
245 * have no valid leaf we try to use MAJOR:default leaf. It still unsuccessfull
246 * then finish and return direct queue.
248 #define HTB_DIRECT (struct htb_class*)-1
249 static inline u32
htb_classid(struct htb_class
*cl
)
251 return (cl
&& cl
!= HTB_DIRECT
) ? cl
->classid
: TC_H_UNSPEC
;
254 static struct htb_class
*htb_classify(struct sk_buff
*skb
, struct Qdisc
*sch
,
257 struct htb_sched
*q
= qdisc_priv(sch
);
258 struct htb_class
*cl
;
259 struct tcf_result res
;
260 struct tcf_proto
*tcf
;
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
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)
271 *qerr
= NET_XMIT_BYPASS
;
272 tcf
= q
->filter_list
;
273 while (tcf
&& (result
= tc_classify(skb
, tcf
, &res
)) >= 0) {
274 #ifdef CONFIG_NET_CLS_ACT
278 *qerr
= NET_XMIT_SUCCESS
;
282 #elif defined(CONFIG_NET_CLS_POLICE)
283 if (result
== TC_POLICE_SHOT
)
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 */
293 return cl
; /* we hit leaf; return it */
295 /* we have got inner class; apply inner filter chain */
296 tcf
= cl
->filter_list
;
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 */
306 * htb_add_to_id_tree - adds class to the round robin list
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.
311 static void htb_add_to_id_tree(struct rb_root
*root
,
312 struct htb_class
*cl
, int prio
)
314 struct rb_node
**p
= &root
->rb_node
, *parent
= NULL
;
319 c
= rb_entry(parent
, struct htb_class
, node
[prio
]);
321 if (cl
->classid
> c
->classid
)
322 p
= &parent
->rb_right
;
324 p
= &parent
->rb_left
;
326 rb_link_node(&cl
->node
[prio
], parent
, p
);
327 rb_insert_color(&cl
->node
[prio
], root
);
331 * htb_add_to_wait_tree - adds class to the event queue with delay
333 * The class is added to priority event queue to indicate that class will
334 * change its mode in cl->pq_key microseconds. Make sure that class is not
335 * already in the queue.
337 static void htb_add_to_wait_tree(struct htb_sched
*q
,
338 struct htb_class
*cl
, long delay
)
340 struct rb_node
**p
= &q
->wait_pq
[cl
->level
].rb_node
, *parent
= NULL
;
342 cl
->pq_key
= q
->jiffies
+ PSCHED_US2JIFFIE(delay
);
343 if (cl
->pq_key
== q
->jiffies
)
346 /* update the nearest event cache */
347 if (time_after(q
->near_ev_cache
[cl
->level
], cl
->pq_key
))
348 q
->near_ev_cache
[cl
->level
] = cl
->pq_key
;
353 c
= rb_entry(parent
, struct htb_class
, pq_node
);
354 if (time_after_eq(cl
->pq_key
, c
->pq_key
))
355 p
= &parent
->rb_right
;
357 p
= &parent
->rb_left
;
359 rb_link_node(&cl
->pq_node
, parent
, p
);
360 rb_insert_color(&cl
->pq_node
, &q
->wait_pq
[cl
->level
]);
364 * htb_next_rb_node - finds next node in binary tree
366 * When we are past last key we return NULL.
367 * Average complexity is 2 steps per call.
369 static inline void htb_next_rb_node(struct rb_node
**n
)
375 * htb_add_class_to_row - add class to its row
377 * The class is added to row at priorities marked in mask.
378 * It does nothing if mask == 0.
380 static inline void htb_add_class_to_row(struct htb_sched
*q
,
381 struct htb_class
*cl
, int mask
)
383 q
->row_mask
[cl
->level
] |= mask
;
385 int prio
= ffz(~mask
);
386 mask
&= ~(1 << prio
);
387 htb_add_to_id_tree(q
->row
[cl
->level
] + prio
, cl
, prio
);
391 /* If this triggers, it is a bug in this code, but it need not be fatal */
392 static void htb_safe_rb_erase(struct rb_node
*rb
, struct rb_root
*root
)
394 if (RB_EMPTY_NODE(rb
)) {
404 * htb_remove_class_from_row - removes class from its row
406 * The class is removed from row at priorities marked in mask.
407 * It does nothing if mask == 0.
409 static inline void htb_remove_class_from_row(struct htb_sched
*q
,
410 struct htb_class
*cl
, int mask
)
415 int prio
= ffz(~mask
);
417 mask
&= ~(1 << prio
);
418 if (q
->ptr
[cl
->level
][prio
] == cl
->node
+ prio
)
419 htb_next_rb_node(q
->ptr
[cl
->level
] + prio
);
421 htb_safe_rb_erase(cl
->node
+ prio
, q
->row
[cl
->level
] + prio
);
422 if (!q
->row
[cl
->level
][prio
].rb_node
)
425 q
->row_mask
[cl
->level
] &= ~m
;
429 * htb_activate_prios - creates active classe's feed chain
431 * The class is connected to ancestors and/or appropriate rows
432 * for priorities it is participating on. cl->cmode must be new
433 * (activated) mode. It does nothing if cl->prio_activity == 0.
435 static void htb_activate_prios(struct htb_sched
*q
, struct htb_class
*cl
)
437 struct htb_class
*p
= cl
->parent
;
438 long m
, mask
= cl
->prio_activity
;
440 while (cl
->cmode
== HTB_MAY_BORROW
&& p
&& mask
) {
446 if (p
->un
.inner
.feed
[prio
].rb_node
)
447 /* parent already has its feed in use so that
448 reset bit in mask as parent is already ok */
449 mask
&= ~(1 << prio
);
451 htb_add_to_id_tree(p
->un
.inner
.feed
+ prio
, cl
, prio
);
453 p
->prio_activity
|= mask
;
458 if (cl
->cmode
== HTB_CAN_SEND
&& mask
)
459 htb_add_class_to_row(q
, cl
, mask
);
463 * htb_deactivate_prios - remove class from feed chain
465 * cl->cmode must represent old mode (before deactivation). It does
466 * nothing if cl->prio_activity == 0. Class is removed from all feed
469 static void htb_deactivate_prios(struct htb_sched
*q
, struct htb_class
*cl
)
471 struct htb_class
*p
= cl
->parent
;
472 long m
, mask
= cl
->prio_activity
;
474 while (cl
->cmode
== HTB_MAY_BORROW
&& p
&& mask
) {
481 if (p
->un
.inner
.ptr
[prio
] == cl
->node
+ prio
) {
482 /* we are removing child which is pointed to from
483 parent feed - forget the pointer but remember
485 p
->un
.inner
.last_ptr_id
[prio
] = cl
->classid
;
486 p
->un
.inner
.ptr
[prio
] = NULL
;
489 htb_safe_rb_erase(cl
->node
+ prio
, p
->un
.inner
.feed
+ prio
);
491 if (!p
->un
.inner
.feed
[prio
].rb_node
)
495 p
->prio_activity
&= ~mask
;
500 if (cl
->cmode
== HTB_CAN_SEND
&& mask
)
501 htb_remove_class_from_row(q
, cl
, mask
);
505 static inline long htb_lowater(const struct htb_class
*cl
)
507 return cl
->cmode
!= HTB_CANT_SEND
? -cl
->cbuffer
: 0;
509 static inline long htb_hiwater(const struct htb_class
*cl
)
511 return cl
->cmode
== HTB_CAN_SEND
? -cl
->buffer
: 0;
514 #define htb_lowater(cl) (0)
515 #define htb_hiwater(cl) (0)
519 * htb_class_mode - computes and returns current class mode
521 * It computes cl's mode at time cl->t_c+diff and returns it. If mode
522 * is not HTB_CAN_SEND then cl->pq_key is updated to time difference
523 * from now to time when cl will change its state.
524 * Also it is worth to note that class mode doesn't change simply
525 * at cl->{c,}tokens == 0 but there can rather be hysteresis of
526 * 0 .. -cl->{c,}buffer range. It is meant to limit number of
527 * mode transitions per time unit. The speed gain is about 1/6.
529 static inline enum htb_cmode
530 htb_class_mode(struct htb_class
*cl
, long *diff
)
534 if ((toks
= (cl
->ctokens
+ *diff
)) < htb_lowater(cl
)) {
536 return HTB_CANT_SEND
;
539 if ((toks
= (cl
->tokens
+ *diff
)) >= htb_hiwater(cl
))
543 return HTB_MAY_BORROW
;
547 * htb_change_class_mode - changes classe's mode
549 * This should be the only way how to change classe's mode under normal
550 * cirsumstances. Routine will update feed lists linkage, change mode
551 * and add class to the wait event queue if appropriate. New mode should
552 * be different from old one and cl->pq_key has to be valid if changing
553 * to mode other than HTB_CAN_SEND (see htb_add_to_wait_tree).
556 htb_change_class_mode(struct htb_sched
*q
, struct htb_class
*cl
, long *diff
)
558 enum htb_cmode new_mode
= htb_class_mode(cl
, diff
);
560 if (new_mode
== cl
->cmode
)
563 if (cl
->prio_activity
) { /* not necessary: speed optimization */
564 if (cl
->cmode
!= HTB_CANT_SEND
)
565 htb_deactivate_prios(q
, cl
);
566 cl
->cmode
= new_mode
;
567 if (new_mode
!= HTB_CANT_SEND
)
568 htb_activate_prios(q
, cl
);
570 cl
->cmode
= new_mode
;
574 * htb_activate - inserts leaf cl into appropriate active feeds
576 * Routine learns (new) priority of leaf and activates feed chain
577 * for the prio. It can be called on already active leaf safely.
578 * It also adds leaf into droplist.
580 static inline void htb_activate(struct htb_sched
*q
, struct htb_class
*cl
)
582 BUG_TRAP(!cl
->level
&& cl
->un
.leaf
.q
&& cl
->un
.leaf
.q
->q
.qlen
);
584 if (!cl
->prio_activity
) {
585 cl
->prio_activity
= 1 << (cl
->un
.leaf
.aprio
= cl
->un
.leaf
.prio
);
586 htb_activate_prios(q
, cl
);
587 list_add_tail(&cl
->un
.leaf
.drop_list
,
588 q
->drops
+ cl
->un
.leaf
.aprio
);
593 * htb_deactivate - remove leaf cl from active feeds
595 * Make sure that leaf is active. In the other words it can't be called
596 * with non-active leaf. It also removes class from the drop list.
598 static inline void htb_deactivate(struct htb_sched
*q
, struct htb_class
*cl
)
600 BUG_TRAP(cl
->prio_activity
);
602 htb_deactivate_prios(q
, cl
);
603 cl
->prio_activity
= 0;
604 list_del_init(&cl
->un
.leaf
.drop_list
);
607 static int htb_enqueue(struct sk_buff
*skb
, struct Qdisc
*sch
)
610 struct htb_sched
*q
= qdisc_priv(sch
);
611 struct htb_class
*cl
= htb_classify(skb
, sch
, &ret
);
613 if (cl
== HTB_DIRECT
) {
614 /* enqueue to helper queue */
615 if (q
->direct_queue
.qlen
< q
->direct_qlen
) {
616 __skb_queue_tail(&q
->direct_queue
, skb
);
621 return NET_XMIT_DROP
;
623 #ifdef CONFIG_NET_CLS_ACT
625 if (ret
== NET_XMIT_BYPASS
)
630 } else if (cl
->un
.leaf
.q
->enqueue(skb
, cl
->un
.leaf
.q
) !=
634 return NET_XMIT_DROP
;
636 cl
->bstats
.packets
++;
637 cl
->bstats
.bytes
+= skb
->len
;
642 sch
->bstats
.packets
++;
643 sch
->bstats
.bytes
+= skb
->len
;
644 return NET_XMIT_SUCCESS
;
647 /* TODO: requeuing packet charges it to policers again !! */
648 static int htb_requeue(struct sk_buff
*skb
, struct Qdisc
*sch
)
650 struct htb_sched
*q
= qdisc_priv(sch
);
651 int ret
= NET_XMIT_SUCCESS
;
652 struct htb_class
*cl
= htb_classify(skb
, sch
, &ret
);
653 struct sk_buff
*tskb
;
655 if (cl
== HTB_DIRECT
|| !cl
) {
656 /* enqueue to helper queue */
657 if (q
->direct_queue
.qlen
< q
->direct_qlen
&& cl
) {
658 __skb_queue_head(&q
->direct_queue
, skb
);
660 __skb_queue_head(&q
->direct_queue
, skb
);
661 tskb
= __skb_dequeue_tail(&q
->direct_queue
);
666 } else if (cl
->un
.leaf
.q
->ops
->requeue(skb
, cl
->un
.leaf
.q
) !=
670 return NET_XMIT_DROP
;
675 sch
->qstats
.requeues
++;
676 return NET_XMIT_SUCCESS
;
679 static void htb_timer(unsigned long arg
)
681 struct Qdisc
*sch
= (struct Qdisc
*)arg
;
682 sch
->flags
&= ~TCQ_F_THROTTLED
;
684 netif_schedule(sch
->dev
);
688 #define RT_GEN(D,R) R+=D-(R/HTB_EWMAC);D=0
689 static void htb_rate_timer(unsigned long arg
)
691 struct Qdisc
*sch
= (struct Qdisc
*)arg
;
692 struct htb_sched
*q
= qdisc_priv(sch
);
693 struct hlist_node
*p
;
694 struct htb_class
*cl
;
697 /* lock queue so that we can muck with it */
698 spin_lock_bh(&sch
->dev
->queue_lock
);
700 q
->rttim
.expires
= jiffies
+ HZ
;
701 add_timer(&q
->rttim
);
703 /* scan and recompute one bucket at time */
704 if (++q
->recmp_bucket
>= HTB_HSIZE
)
707 hlist_for_each_entry(cl
,p
, q
->hash
+ q
->recmp_bucket
, hlist
) {
708 RT_GEN(cl
->sum_bytes
, cl
->rate_bytes
);
709 RT_GEN(cl
->sum_packets
, cl
->rate_packets
);
711 spin_unlock_bh(&sch
->dev
->queue_lock
);
716 * htb_charge_class - charges amount "bytes" to leaf and ancestors
718 * Routine assumes that packet "bytes" long was dequeued from leaf cl
719 * borrowing from "level". It accounts bytes to ceil leaky bucket for
720 * leaf and all ancestors and to rate bucket for ancestors at levels
721 * "level" and higher. It also handles possible change of mode resulting
722 * from the update. Note that mode can also increase here (MAY_BORROW to
723 * CAN_SEND) because we can use more precise clock that event queue here.
724 * In such case we remove class from event queue first.
726 static void htb_charge_class(struct htb_sched
*q
, struct htb_class
*cl
,
727 int level
, int bytes
)
730 enum htb_cmode old_mode
;
732 #define HTB_ACCNT(T,B,R) toks = diff + cl->T; \
733 if (toks > cl->B) toks = cl->B; \
734 toks -= L2T(cl, cl->R, bytes); \
735 if (toks <= -cl->mbuffer) toks = 1-cl->mbuffer; \
739 diff
= PSCHED_TDIFF_SAFE(q
->now
, cl
->t_c
, (u32
) cl
->mbuffer
);
740 if (cl
->level
>= level
) {
741 if (cl
->level
== level
)
743 HTB_ACCNT(tokens
, buffer
, rate
);
745 cl
->xstats
.borrows
++;
746 cl
->tokens
+= diff
; /* we moved t_c; update tokens */
748 HTB_ACCNT(ctokens
, cbuffer
, ceil
);
751 old_mode
= cl
->cmode
;
753 htb_change_class_mode(q
, cl
, &diff
);
754 if (old_mode
!= cl
->cmode
) {
755 if (old_mode
!= HTB_CAN_SEND
)
756 htb_safe_rb_erase(&cl
->pq_node
, q
->wait_pq
+ cl
->level
);
757 if (cl
->cmode
!= HTB_CAN_SEND
)
758 htb_add_to_wait_tree(q
, cl
, diff
);
761 /* update rate counters */
762 cl
->sum_bytes
+= bytes
;
766 /* update byte stats except for leaves which are already updated */
768 cl
->bstats
.bytes
+= bytes
;
769 cl
->bstats
.packets
++;
776 * htb_do_events - make mode changes to classes at the level
778 * Scans event queue for pending events and applies them. Returns jiffies to
779 * next pending event (0 for no event in pq).
780 * Note: Aplied are events whose have cl->pq_key <= jiffies.
782 static long htb_do_events(struct htb_sched
*q
, int level
)
786 for (i
= 0; i
< 500; i
++) {
787 struct htb_class
*cl
;
789 struct rb_node
*p
= rb_first(&q
->wait_pq
[level
]);
794 cl
= rb_entry(p
, struct htb_class
, pq_node
);
795 if (time_after(cl
->pq_key
, q
->jiffies
)) {
796 return cl
->pq_key
- q
->jiffies
;
798 htb_safe_rb_erase(p
, q
->wait_pq
+ level
);
799 diff
= PSCHED_TDIFF_SAFE(q
->now
, cl
->t_c
, (u32
) cl
->mbuffer
);
800 htb_change_class_mode(q
, cl
, &diff
);
801 if (cl
->cmode
!= HTB_CAN_SEND
)
802 htb_add_to_wait_tree(q
, cl
, diff
);
805 printk(KERN_WARNING
"htb: too many events !\n");
809 /* Returns class->node+prio from id-tree where classe's id is >= id. NULL
810 is no such one exists. */
811 static struct rb_node
*htb_id_find_next_upper(int prio
, struct rb_node
*n
,
814 struct rb_node
*r
= NULL
;
816 struct htb_class
*cl
=
817 rb_entry(n
, struct htb_class
, node
[prio
]);
818 if (id
== cl
->classid
)
821 if (id
> cl
->classid
) {
832 * htb_lookup_leaf - returns next leaf class in DRR order
834 * Find leaf where current feed pointers points to.
836 static struct htb_class
*htb_lookup_leaf(struct rb_root
*tree
, int prio
,
837 struct rb_node
**pptr
, u32
* pid
)
841 struct rb_node
*root
;
842 struct rb_node
**pptr
;
844 } stk
[TC_HTB_MAXDEPTH
], *sp
= stk
;
846 BUG_TRAP(tree
->rb_node
);
847 sp
->root
= tree
->rb_node
;
851 for (i
= 0; i
< 65535; i
++) {
852 if (!*sp
->pptr
&& *sp
->pid
) {
853 /* ptr was invalidated but id is valid - try to recover
854 the original or next ptr */
856 htb_id_find_next_upper(prio
, sp
->root
, *sp
->pid
);
858 *sp
->pid
= 0; /* ptr is valid now so that remove this hint as it
859 can become out of date quickly */
860 if (!*sp
->pptr
) { /* we are at right end; rewind & go up */
861 *sp
->pptr
= sp
->root
;
862 while ((*sp
->pptr
)->rb_left
)
863 *sp
->pptr
= (*sp
->pptr
)->rb_left
;
869 htb_next_rb_node(sp
->pptr
);
872 struct htb_class
*cl
;
873 cl
= rb_entry(*sp
->pptr
, struct htb_class
, node
[prio
]);
876 (++sp
)->root
= cl
->un
.inner
.feed
[prio
].rb_node
;
877 sp
->pptr
= cl
->un
.inner
.ptr
+ prio
;
878 sp
->pid
= cl
->un
.inner
.last_ptr_id
+ prio
;
885 /* dequeues packet at given priority and level; call only if
886 you are sure that there is active class at prio/level */
887 static struct sk_buff
*htb_dequeue_tree(struct htb_sched
*q
, int prio
,
890 struct sk_buff
*skb
= NULL
;
891 struct htb_class
*cl
, *start
;
892 /* look initial class up in the row */
893 start
= cl
= htb_lookup_leaf(q
->row
[level
] + prio
, prio
,
894 q
->ptr
[level
] + prio
,
895 q
->last_ptr_id
[level
] + prio
);
903 /* class can be empty - it is unlikely but can be true if leaf
904 qdisc drops packets in enqueue routine or if someone used
905 graft operation on the leaf since last dequeue;
906 simply deactivate and skip such class */
907 if (unlikely(cl
->un
.leaf
.q
->q
.qlen
== 0)) {
908 struct htb_class
*next
;
909 htb_deactivate(q
, cl
);
911 /* row/level might become empty */
912 if ((q
->row_mask
[level
] & (1 << prio
)) == 0)
915 next
= htb_lookup_leaf(q
->row
[level
] + prio
,
916 prio
, q
->ptr
[level
] + prio
,
917 q
->last_ptr_id
[level
] + prio
);
919 if (cl
== start
) /* fix start if we just deleted it */
925 skb
= cl
->un
.leaf
.q
->dequeue(cl
->un
.leaf
.q
);
926 if (likely(skb
!= NULL
))
930 "htb: class %X isn't work conserving ?!\n",
935 htb_next_rb_node((level
? cl
->parent
->un
.inner
.ptr
: q
->
937 cl
= htb_lookup_leaf(q
->row
[level
] + prio
, prio
,
938 q
->ptr
[level
] + prio
,
939 q
->last_ptr_id
[level
] + prio
);
941 } while (cl
!= start
);
943 if (likely(skb
!= NULL
)) {
944 if ((cl
->un
.leaf
.deficit
[level
] -= skb
->len
) < 0) {
945 cl
->un
.leaf
.deficit
[level
] += cl
->un
.leaf
.quantum
;
946 htb_next_rb_node((level
? cl
->parent
->un
.inner
.ptr
: q
->
949 /* this used to be after charge_class but this constelation
950 gives us slightly better performance */
951 if (!cl
->un
.leaf
.q
->q
.qlen
)
952 htb_deactivate(q
, cl
);
953 htb_charge_class(q
, cl
, level
, skb
->len
);
958 static void htb_delay_by(struct Qdisc
*sch
, long delay
)
960 struct htb_sched
*q
= qdisc_priv(sch
);
963 if (unlikely(delay
> 5 * HZ
)) {
965 printk(KERN_INFO
"HTB delay %ld > 5sec\n", delay
);
968 /* why don't use jiffies here ? because expires can be in past */
969 mod_timer(&q
->timer
, q
->jiffies
+ delay
);
970 sch
->flags
|= TCQ_F_THROTTLED
;
971 sch
->qstats
.overlimits
++;
974 static struct sk_buff
*htb_dequeue(struct Qdisc
*sch
)
976 struct sk_buff
*skb
= NULL
;
977 struct htb_sched
*q
= qdisc_priv(sch
);
981 q
->jiffies
= jiffies
;
983 /* try to dequeue direct packets as high prio (!) to minimize cpu work */
984 skb
= __skb_dequeue(&q
->direct_queue
);
986 sch
->flags
&= ~TCQ_F_THROTTLED
;
993 PSCHED_GET_TIME(q
->now
);
995 min_delay
= LONG_MAX
;
997 for (level
= 0; level
< TC_HTB_MAXDEPTH
; level
++) {
998 /* common case optimization - skip event handler quickly */
1001 if (time_after_eq(q
->jiffies
, q
->near_ev_cache
[level
])) {
1002 delay
= htb_do_events(q
, level
);
1003 q
->near_ev_cache
[level
] =
1004 q
->jiffies
+ (delay
? delay
: HZ
);
1006 delay
= q
->near_ev_cache
[level
] - q
->jiffies
;
1008 if (delay
&& min_delay
> delay
)
1010 m
= ~q
->row_mask
[level
];
1011 while (m
!= (int)(-1)) {
1014 skb
= htb_dequeue_tree(q
, prio
, level
);
1015 if (likely(skb
!= NULL
)) {
1017 sch
->flags
&= ~TCQ_F_THROTTLED
;
1022 htb_delay_by(sch
, min_delay
> 5 * HZ
? 5 * HZ
: min_delay
);
1027 /* try to drop from each class (by prio) until one succeed */
1028 static unsigned int htb_drop(struct Qdisc
*sch
)
1030 struct htb_sched
*q
= qdisc_priv(sch
);
1033 for (prio
= TC_HTB_NUMPRIO
- 1; prio
>= 0; prio
--) {
1034 struct list_head
*p
;
1035 list_for_each(p
, q
->drops
+ prio
) {
1036 struct htb_class
*cl
= list_entry(p
, struct htb_class
,
1039 if (cl
->un
.leaf
.q
->ops
->drop
&&
1040 (len
= cl
->un
.leaf
.q
->ops
->drop(cl
->un
.leaf
.q
))) {
1042 if (!cl
->un
.leaf
.q
->q
.qlen
)
1043 htb_deactivate(q
, cl
);
1051 /* reset all classes */
1052 /* always caled under BH & queue lock */
1053 static void htb_reset(struct Qdisc
*sch
)
1055 struct htb_sched
*q
= qdisc_priv(sch
);
1058 for (i
= 0; i
< HTB_HSIZE
; i
++) {
1059 struct hlist_node
*p
;
1060 struct htb_class
*cl
;
1062 hlist_for_each_entry(cl
, p
, q
->hash
+ i
, hlist
) {
1064 memset(&cl
->un
.inner
, 0, sizeof(cl
->un
.inner
));
1067 qdisc_reset(cl
->un
.leaf
.q
);
1068 INIT_LIST_HEAD(&cl
->un
.leaf
.drop_list
);
1070 cl
->prio_activity
= 0;
1071 cl
->cmode
= HTB_CAN_SEND
;
1075 sch
->flags
&= ~TCQ_F_THROTTLED
;
1076 del_timer(&q
->timer
);
1077 __skb_queue_purge(&q
->direct_queue
);
1079 memset(q
->row
, 0, sizeof(q
->row
));
1080 memset(q
->row_mask
, 0, sizeof(q
->row_mask
));
1081 memset(q
->wait_pq
, 0, sizeof(q
->wait_pq
));
1082 memset(q
->ptr
, 0, sizeof(q
->ptr
));
1083 for (i
= 0; i
< TC_HTB_NUMPRIO
; i
++)
1084 INIT_LIST_HEAD(q
->drops
+ i
);
1087 static int htb_init(struct Qdisc
*sch
, struct rtattr
*opt
)
1089 struct htb_sched
*q
= qdisc_priv(sch
);
1090 struct rtattr
*tb
[TCA_HTB_INIT
];
1091 struct tc_htb_glob
*gopt
;
1093 if (!opt
|| rtattr_parse_nested(tb
, TCA_HTB_INIT
, opt
) ||
1094 tb
[TCA_HTB_INIT
- 1] == NULL
||
1095 RTA_PAYLOAD(tb
[TCA_HTB_INIT
- 1]) < sizeof(*gopt
)) {
1096 printk(KERN_ERR
"HTB: hey probably you have bad tc tool ?\n");
1099 gopt
= RTA_DATA(tb
[TCA_HTB_INIT
- 1]);
1100 if (gopt
->version
!= HTB_VER
>> 16) {
1102 "HTB: need tc/htb version %d (minor is %d), you have %d\n",
1103 HTB_VER
>> 16, HTB_VER
& 0xffff, gopt
->version
);
1107 INIT_LIST_HEAD(&q
->root
);
1108 for (i
= 0; i
< HTB_HSIZE
; i
++)
1109 INIT_HLIST_HEAD(q
->hash
+ i
);
1110 for (i
= 0; i
< TC_HTB_NUMPRIO
; i
++)
1111 INIT_LIST_HEAD(q
->drops
+ i
);
1113 init_timer(&q
->timer
);
1114 skb_queue_head_init(&q
->direct_queue
);
1116 q
->direct_qlen
= sch
->dev
->tx_queue_len
;
1117 if (q
->direct_qlen
< 2) /* some devices have zero tx_queue_len */
1119 q
->timer
.function
= htb_timer
;
1120 q
->timer
.data
= (unsigned long)sch
;
1123 init_timer(&q
->rttim
);
1124 q
->rttim
.function
= htb_rate_timer
;
1125 q
->rttim
.data
= (unsigned long)sch
;
1126 q
->rttim
.expires
= jiffies
+ HZ
;
1127 add_timer(&q
->rttim
);
1129 if ((q
->rate2quantum
= gopt
->rate2quantum
) < 1)
1130 q
->rate2quantum
= 1;
1131 q
->defcls
= gopt
->defcls
;
1136 static int htb_dump(struct Qdisc
*sch
, struct sk_buff
*skb
)
1138 struct htb_sched
*q
= qdisc_priv(sch
);
1139 unsigned char *b
= skb
->tail
;
1141 struct tc_htb_glob gopt
;
1142 spin_lock_bh(&sch
->dev
->queue_lock
);
1143 gopt
.direct_pkts
= q
->direct_pkts
;
1145 gopt
.version
= HTB_VER
;
1146 gopt
.rate2quantum
= q
->rate2quantum
;
1147 gopt
.defcls
= q
->defcls
;
1149 rta
= (struct rtattr
*)b
;
1150 RTA_PUT(skb
, TCA_OPTIONS
, 0, NULL
);
1151 RTA_PUT(skb
, TCA_HTB_INIT
, sizeof(gopt
), &gopt
);
1152 rta
->rta_len
= skb
->tail
- b
;
1153 spin_unlock_bh(&sch
->dev
->queue_lock
);
1156 spin_unlock_bh(&sch
->dev
->queue_lock
);
1157 skb_trim(skb
, skb
->tail
- skb
->data
);
1161 static int htb_dump_class(struct Qdisc
*sch
, unsigned long arg
,
1162 struct sk_buff
*skb
, struct tcmsg
*tcm
)
1164 struct htb_class
*cl
= (struct htb_class
*)arg
;
1165 unsigned char *b
= skb
->tail
;
1167 struct tc_htb_opt opt
;
1169 spin_lock_bh(&sch
->dev
->queue_lock
);
1170 tcm
->tcm_parent
= cl
->parent
? cl
->parent
->classid
: TC_H_ROOT
;
1171 tcm
->tcm_handle
= cl
->classid
;
1172 if (!cl
->level
&& cl
->un
.leaf
.q
)
1173 tcm
->tcm_info
= cl
->un
.leaf
.q
->handle
;
1175 rta
= (struct rtattr
*)b
;
1176 RTA_PUT(skb
, TCA_OPTIONS
, 0, NULL
);
1178 memset(&opt
, 0, sizeof(opt
));
1180 opt
.rate
= cl
->rate
->rate
;
1181 opt
.buffer
= cl
->buffer
;
1182 opt
.ceil
= cl
->ceil
->rate
;
1183 opt
.cbuffer
= cl
->cbuffer
;
1184 opt
.quantum
= cl
->un
.leaf
.quantum
;
1185 opt
.prio
= cl
->un
.leaf
.prio
;
1186 opt
.level
= cl
->level
;
1187 RTA_PUT(skb
, TCA_HTB_PARMS
, sizeof(opt
), &opt
);
1188 rta
->rta_len
= skb
->tail
- b
;
1189 spin_unlock_bh(&sch
->dev
->queue_lock
);
1192 spin_unlock_bh(&sch
->dev
->queue_lock
);
1193 skb_trim(skb
, b
- skb
->data
);
1198 htb_dump_class_stats(struct Qdisc
*sch
, unsigned long arg
, struct gnet_dump
*d
)
1200 struct htb_class
*cl
= (struct htb_class
*)arg
;
1203 cl
->rate_est
.bps
= cl
->rate_bytes
/ (HTB_EWMAC
* HTB_HSIZE
);
1204 cl
->rate_est
.pps
= cl
->rate_packets
/ (HTB_EWMAC
* HTB_HSIZE
);
1207 if (!cl
->level
&& cl
->un
.leaf
.q
)
1208 cl
->qstats
.qlen
= cl
->un
.leaf
.q
->q
.qlen
;
1209 cl
->xstats
.tokens
= cl
->tokens
;
1210 cl
->xstats
.ctokens
= cl
->ctokens
;
1212 if (gnet_stats_copy_basic(d
, &cl
->bstats
) < 0 ||
1213 gnet_stats_copy_rate_est(d
, &cl
->rate_est
) < 0 ||
1214 gnet_stats_copy_queue(d
, &cl
->qstats
) < 0)
1217 return gnet_stats_copy_app(d
, &cl
->xstats
, sizeof(cl
->xstats
));
1220 static int htb_graft(struct Qdisc
*sch
, unsigned long arg
, struct Qdisc
*new,
1223 struct htb_class
*cl
= (struct htb_class
*)arg
;
1225 if (cl
&& !cl
->level
) {
1227 (new = qdisc_create_dflt(sch
->dev
, &pfifo_qdisc_ops
,
1232 if ((*old
= xchg(&cl
->un
.leaf
.q
, new)) != NULL
) {
1233 if (cl
->prio_activity
)
1234 htb_deactivate(qdisc_priv(sch
), cl
);
1236 /* TODO: is it correct ? Why CBQ doesn't do it ? */
1237 sch
->q
.qlen
-= (*old
)->q
.qlen
;
1240 sch_tree_unlock(sch
);
1246 static struct Qdisc
*htb_leaf(struct Qdisc
*sch
, unsigned long arg
)
1248 struct htb_class
*cl
= (struct htb_class
*)arg
;
1249 return (cl
&& !cl
->level
) ? cl
->un
.leaf
.q
: NULL
;
1252 static unsigned long htb_get(struct Qdisc
*sch
, u32 classid
)
1254 struct htb_class
*cl
= htb_find(classid
, sch
);
1257 return (unsigned long)cl
;
1260 static void htb_destroy_filters(struct tcf_proto
**fl
)
1262 struct tcf_proto
*tp
;
1264 while ((tp
= *fl
) != NULL
) {
1270 static void htb_destroy_class(struct Qdisc
*sch
, struct htb_class
*cl
)
1272 struct htb_sched
*q
= qdisc_priv(sch
);
1275 BUG_TRAP(cl
->un
.leaf
.q
);
1276 qdisc_destroy(cl
->un
.leaf
.q
);
1278 qdisc_put_rtab(cl
->rate
);
1279 qdisc_put_rtab(cl
->ceil
);
1281 htb_destroy_filters(&cl
->filter_list
);
1283 while (!list_empty(&cl
->children
))
1284 htb_destroy_class(sch
, list_entry(cl
->children
.next
,
1285 struct htb_class
, sibling
));
1287 /* note: this delete may happen twice (see htb_delete) */
1288 hlist_del_init(&cl
->hlist
);
1289 list_del(&cl
->sibling
);
1291 if (cl
->prio_activity
)
1292 htb_deactivate(q
, cl
);
1294 if (cl
->cmode
!= HTB_CAN_SEND
)
1295 htb_safe_rb_erase(&cl
->pq_node
, q
->wait_pq
+ cl
->level
);
1300 /* always caled under BH & queue lock */
1301 static void htb_destroy(struct Qdisc
*sch
)
1303 struct htb_sched
*q
= qdisc_priv(sch
);
1305 del_timer_sync(&q
->timer
);
1307 del_timer_sync(&q
->rttim
);
1309 /* This line used to be after htb_destroy_class call below
1310 and surprisingly it worked in 2.4. But it must precede it
1311 because filter need its target class alive to be able to call
1312 unbind_filter on it (without Oops). */
1313 htb_destroy_filters(&q
->filter_list
);
1315 while (!list_empty(&q
->root
))
1316 htb_destroy_class(sch
, list_entry(q
->root
.next
,
1317 struct htb_class
, sibling
));
1319 __skb_queue_purge(&q
->direct_queue
);
1322 static int htb_delete(struct Qdisc
*sch
, unsigned long arg
)
1324 struct htb_sched
*q
= qdisc_priv(sch
);
1325 struct htb_class
*cl
= (struct htb_class
*)arg
;
1327 // TODO: why don't allow to delete subtree ? references ? does
1328 // tc subsys quarantee us that in htb_destroy it holds no class
1329 // refs so that we can remove children safely there ?
1330 if (!list_empty(&cl
->children
) || cl
->filter_cnt
)
1335 /* delete from hash and active; remainder in destroy_class */
1336 hlist_del_init(&cl
->hlist
);
1339 sch
->q
.qlen
-= cl
->un
.leaf
.q
->q
.qlen
;
1340 qdisc_reset(cl
->un
.leaf
.q
);
1343 if (cl
->prio_activity
)
1344 htb_deactivate(q
, cl
);
1346 if (--cl
->refcnt
== 0)
1347 htb_destroy_class(sch
, cl
);
1349 sch_tree_unlock(sch
);
1353 static void htb_put(struct Qdisc
*sch
, unsigned long arg
)
1355 struct htb_class
*cl
= (struct htb_class
*)arg
;
1357 if (--cl
->refcnt
== 0)
1358 htb_destroy_class(sch
, cl
);
1361 static int htb_change_class(struct Qdisc
*sch
, u32 classid
,
1362 u32 parentid
, struct rtattr
**tca
,
1366 struct htb_sched
*q
= qdisc_priv(sch
);
1367 struct htb_class
*cl
= (struct htb_class
*)*arg
, *parent
;
1368 struct rtattr
*opt
= tca
[TCA_OPTIONS
- 1];
1369 struct qdisc_rate_table
*rtab
= NULL
, *ctab
= NULL
;
1370 struct rtattr
*tb
[TCA_HTB_RTAB
];
1371 struct tc_htb_opt
*hopt
;
1373 /* extract all subattrs from opt attr */
1374 if (!opt
|| rtattr_parse_nested(tb
, TCA_HTB_RTAB
, opt
) ||
1375 tb
[TCA_HTB_PARMS
- 1] == NULL
||
1376 RTA_PAYLOAD(tb
[TCA_HTB_PARMS
- 1]) < sizeof(*hopt
))
1379 parent
= parentid
== TC_H_ROOT
? NULL
: htb_find(parentid
, sch
);
1381 hopt
= RTA_DATA(tb
[TCA_HTB_PARMS
- 1]);
1383 rtab
= qdisc_get_rtab(&hopt
->rate
, tb
[TCA_HTB_RTAB
- 1]);
1384 ctab
= qdisc_get_rtab(&hopt
->ceil
, tb
[TCA_HTB_CTAB
- 1]);
1388 if (!cl
) { /* new class */
1389 struct Qdisc
*new_q
;
1392 /* check for valid classid */
1393 if (!classid
|| TC_H_MAJ(classid
^ sch
->handle
)
1394 || htb_find(classid
, sch
))
1397 /* check maximal depth */
1398 if (parent
&& parent
->parent
&& parent
->parent
->level
< 2) {
1399 printk(KERN_ERR
"htb: tree is too deep\n");
1403 if ((cl
= kzalloc(sizeof(*cl
), GFP_KERNEL
)) == NULL
)
1407 INIT_LIST_HEAD(&cl
->sibling
);
1408 INIT_HLIST_NODE(&cl
->hlist
);
1409 INIT_LIST_HEAD(&cl
->children
);
1410 INIT_LIST_HEAD(&cl
->un
.leaf
.drop_list
);
1411 RB_CLEAR_NODE(&cl
->pq_node
);
1413 for (prio
= 0; prio
< TC_HTB_NUMPRIO
; prio
++)
1414 RB_CLEAR_NODE(&cl
->node
[prio
]);
1416 /* create leaf qdisc early because it uses kmalloc(GFP_KERNEL)
1417 so that can't be used inside of sch_tree_lock
1418 -- thanks to Karlis Peisenieks */
1419 new_q
= qdisc_create_dflt(sch
->dev
, &pfifo_qdisc_ops
, classid
);
1421 if (parent
&& !parent
->level
) {
1422 /* turn parent into inner node */
1423 sch
->q
.qlen
-= parent
->un
.leaf
.q
->q
.qlen
;
1424 qdisc_destroy(parent
->un
.leaf
.q
);
1425 if (parent
->prio_activity
)
1426 htb_deactivate(q
, parent
);
1428 /* remove from evt list because of level change */
1429 if (parent
->cmode
!= HTB_CAN_SEND
) {
1430 htb_safe_rb_erase(&parent
->pq_node
, q
->wait_pq
);
1431 parent
->cmode
= HTB_CAN_SEND
;
1433 parent
->level
= (parent
->parent
? parent
->parent
->level
1434 : TC_HTB_MAXDEPTH
) - 1;
1435 memset(&parent
->un
.inner
, 0, sizeof(parent
->un
.inner
));
1437 /* leaf (we) needs elementary qdisc */
1438 cl
->un
.leaf
.q
= new_q
? new_q
: &noop_qdisc
;
1440 cl
->classid
= classid
;
1441 cl
->parent
= parent
;
1443 /* set class to be in HTB_CAN_SEND state */
1444 cl
->tokens
= hopt
->buffer
;
1445 cl
->ctokens
= hopt
->cbuffer
;
1446 cl
->mbuffer
= PSCHED_JIFFIE2US(HZ
* 60); /* 1min */
1447 PSCHED_GET_TIME(cl
->t_c
);
1448 cl
->cmode
= HTB_CAN_SEND
;
1450 /* attach to the hash list and parent's family */
1451 hlist_add_head(&cl
->hlist
, q
->hash
+ htb_hash(classid
));
1452 list_add_tail(&cl
->sibling
,
1453 parent
? &parent
->children
: &q
->root
);
1457 /* it used to be a nasty bug here, we have to check that node
1458 is really leaf before changing cl->un.leaf ! */
1460 cl
->un
.leaf
.quantum
= rtab
->rate
.rate
/ q
->rate2quantum
;
1461 if (!hopt
->quantum
&& cl
->un
.leaf
.quantum
< 1000) {
1463 "HTB: quantum of class %X is small. Consider r2q change.\n",
1465 cl
->un
.leaf
.quantum
= 1000;
1467 if (!hopt
->quantum
&& cl
->un
.leaf
.quantum
> 200000) {
1469 "HTB: quantum of class %X is big. Consider r2q change.\n",
1471 cl
->un
.leaf
.quantum
= 200000;
1474 cl
->un
.leaf
.quantum
= hopt
->quantum
;
1475 if ((cl
->un
.leaf
.prio
= hopt
->prio
) >= TC_HTB_NUMPRIO
)
1476 cl
->un
.leaf
.prio
= TC_HTB_NUMPRIO
- 1;
1479 cl
->buffer
= hopt
->buffer
;
1480 cl
->cbuffer
= hopt
->cbuffer
;
1482 qdisc_put_rtab(cl
->rate
);
1485 qdisc_put_rtab(cl
->ceil
);
1487 sch_tree_unlock(sch
);
1489 *arg
= (unsigned long)cl
;
1494 qdisc_put_rtab(rtab
);
1496 qdisc_put_rtab(ctab
);
1500 static struct tcf_proto
**htb_find_tcf(struct Qdisc
*sch
, unsigned long arg
)
1502 struct htb_sched
*q
= qdisc_priv(sch
);
1503 struct htb_class
*cl
= (struct htb_class
*)arg
;
1504 struct tcf_proto
**fl
= cl
? &cl
->filter_list
: &q
->filter_list
;
1509 static unsigned long htb_bind_filter(struct Qdisc
*sch
, unsigned long parent
,
1512 struct htb_sched
*q
= qdisc_priv(sch
);
1513 struct htb_class
*cl
= htb_find(classid
, sch
);
1515 /*if (cl && !cl->level) return 0;
1516 The line above used to be there to prevent attaching filters to
1517 leaves. But at least tc_index filter uses this just to get class
1518 for other reasons so that we have to allow for it.
1520 19.6.2002 As Werner explained it is ok - bind filter is just
1521 another way to "lock" the class - unlike "get" this lock can
1522 be broken by class during destroy IIUC.
1528 return (unsigned long)cl
;
1531 static void htb_unbind_filter(struct Qdisc
*sch
, unsigned long arg
)
1533 struct htb_sched
*q
= qdisc_priv(sch
);
1534 struct htb_class
*cl
= (struct htb_class
*)arg
;
1542 static void htb_walk(struct Qdisc
*sch
, struct qdisc_walker
*arg
)
1544 struct htb_sched
*q
= qdisc_priv(sch
);
1550 for (i
= 0; i
< HTB_HSIZE
; i
++) {
1551 struct hlist_node
*p
;
1552 struct htb_class
*cl
;
1554 hlist_for_each_entry(cl
, p
, q
->hash
+ i
, hlist
) {
1555 if (arg
->count
< arg
->skip
) {
1559 if (arg
->fn(sch
, (unsigned long)cl
, arg
) < 0) {
1568 static struct Qdisc_class_ops htb_class_ops
= {
1573 .change
= htb_change_class
,
1574 .delete = htb_delete
,
1576 .tcf_chain
= htb_find_tcf
,
1577 .bind_tcf
= htb_bind_filter
,
1578 .unbind_tcf
= htb_unbind_filter
,
1579 .dump
= htb_dump_class
,
1580 .dump_stats
= htb_dump_class_stats
,
1583 static struct Qdisc_ops htb_qdisc_ops
= {
1585 .cl_ops
= &htb_class_ops
,
1587 .priv_size
= sizeof(struct htb_sched
),
1588 .enqueue
= htb_enqueue
,
1589 .dequeue
= htb_dequeue
,
1590 .requeue
= htb_requeue
,
1594 .destroy
= htb_destroy
,
1595 .change
= NULL
/* htb_change */,
1597 .owner
= THIS_MODULE
,
1600 static int __init
htb_module_init(void)
1602 return register_qdisc(&htb_qdisc_ops
);
1604 static void __exit
htb_module_exit(void)
1606 unregister_qdisc(&htb_qdisc_ops
);
1609 module_init(htb_module_init
)
1610 module_exit(htb_module_exit
)
1611 MODULE_LICENSE("GPL");