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 */
151 int prio
; /* For parent to leaf return possible here */
152 int quantum
; /* we do backup. Finally full replacement */
153 /* of un.leaf originals should be done. */
156 /* TODO: maybe compute rate when size is too large .. or drop ? */
157 static inline long L2T(struct htb_class
*cl
, struct qdisc_rate_table
*rate
,
160 int slot
= size
>> rate
->rate
.cell_log
;
165 return rate
->data
[slot
];
169 struct list_head root
; /* root classes list */
170 struct hlist_head hash
[HTB_HSIZE
]; /* hashed by classid */
171 struct list_head drops
[TC_HTB_NUMPRIO
];/* active leaves (for drops) */
173 /* self list - roots of self generating tree */
174 struct rb_root row
[TC_HTB_MAXDEPTH
][TC_HTB_NUMPRIO
];
175 int row_mask
[TC_HTB_MAXDEPTH
];
176 struct rb_node
*ptr
[TC_HTB_MAXDEPTH
][TC_HTB_NUMPRIO
];
177 u32 last_ptr_id
[TC_HTB_MAXDEPTH
][TC_HTB_NUMPRIO
];
179 /* self wait list - roots of wait PQs per row */
180 struct rb_root wait_pq
[TC_HTB_MAXDEPTH
];
182 /* time of nearest event per level (row) */
183 unsigned long near_ev_cache
[TC_HTB_MAXDEPTH
];
185 /* cached value of jiffies in dequeue */
186 unsigned long jiffies
;
188 /* whether we hit non-work conserving class during this dequeue; we use */
189 int nwc_hit
; /* this to disable mindelay complaint in dequeue */
191 int defcls
; /* class where unclassified flows go to */
193 /* filters for qdisc itself */
194 struct tcf_proto
*filter_list
;
197 int rate2quantum
; /* quant = rate / rate2quantum */
198 psched_time_t now
; /* cached dequeue time */
199 struct timer_list timer
; /* send delay timer */
201 struct timer_list rttim
; /* rate computer timer */
202 int recmp_bucket
; /* which hash bucket to recompute next */
205 /* non shaped skbs; let them go directly thru */
206 struct sk_buff_head direct_queue
;
207 int direct_qlen
; /* max qlen of above */
212 /* compute hash of size HTB_HSIZE for given handle */
213 static inline int htb_hash(u32 h
)
216 #error "Declare new hash for your HTB_HSIZE"
218 h
^= h
>> 8; /* stolen from cbq_hash */
223 /* find class in global hash table using given handle */
224 static inline struct htb_class
*htb_find(u32 handle
, struct Qdisc
*sch
)
226 struct htb_sched
*q
= qdisc_priv(sch
);
227 struct hlist_node
*p
;
228 struct htb_class
*cl
;
230 if (TC_H_MAJ(handle
) != sch
->handle
)
233 hlist_for_each_entry(cl
, p
, q
->hash
+ htb_hash(handle
), hlist
) {
234 if (cl
->classid
== handle
)
241 * htb_classify - classify a packet into class
243 * It returns NULL if the packet should be dropped or -1 if the packet
244 * should be passed directly thru. In all other cases leaf class is returned.
245 * We allow direct class selection by classid in priority. The we examine
246 * filters in qdisc and in inner nodes (if higher filter points to the inner
247 * node). If we end up with classid MAJOR:0 we enqueue the skb into special
248 * internal fifo (direct). These packets then go directly thru. If we still
249 * have no valid leaf we try to use MAJOR:default leaf. It still unsuccessfull
250 * then finish and return direct queue.
252 #define HTB_DIRECT (struct htb_class*)-1
253 static inline u32
htb_classid(struct htb_class
*cl
)
255 return (cl
&& cl
!= HTB_DIRECT
) ? cl
->classid
: TC_H_UNSPEC
;
258 static struct htb_class
*htb_classify(struct sk_buff
*skb
, struct Qdisc
*sch
,
261 struct htb_sched
*q
= qdisc_priv(sch
);
262 struct htb_class
*cl
;
263 struct tcf_result res
;
264 struct tcf_proto
*tcf
;
267 /* allow to select class by setting skb->priority to valid classid;
268 note that nfmark can be used too by attaching filter fw with no
270 if (skb
->priority
== sch
->handle
)
271 return HTB_DIRECT
; /* X:0 (direct flow) selected */
272 if ((cl
= htb_find(skb
->priority
, sch
)) != NULL
&& cl
->level
== 0)
275 *qerr
= NET_XMIT_BYPASS
;
276 tcf
= q
->filter_list
;
277 while (tcf
&& (result
= tc_classify(skb
, tcf
, &res
)) >= 0) {
278 #ifdef CONFIG_NET_CLS_ACT
282 *qerr
= NET_XMIT_SUCCESS
;
286 #elif defined(CONFIG_NET_CLS_POLICE)
287 if (result
== TC_POLICE_SHOT
)
290 if ((cl
= (void *)res
.class) == NULL
) {
291 if (res
.classid
== sch
->handle
)
292 return HTB_DIRECT
; /* X:0 (direct flow) */
293 if ((cl
= htb_find(res
.classid
, sch
)) == NULL
)
294 break; /* filter selected invalid classid */
297 return cl
; /* we hit leaf; return it */
299 /* we have got inner class; apply inner filter chain */
300 tcf
= cl
->filter_list
;
302 /* classification failed; try to use default class */
303 cl
= htb_find(TC_H_MAKE(TC_H_MAJ(sch
->handle
), q
->defcls
), sch
);
304 if (!cl
|| cl
->level
)
305 return HTB_DIRECT
; /* bad default .. this is safe bet */
310 * htb_add_to_id_tree - adds class to the round robin list
312 * Routine adds class to the list (actually tree) sorted by classid.
313 * Make sure that class is not already on such list for given prio.
315 static void htb_add_to_id_tree(struct rb_root
*root
,
316 struct htb_class
*cl
, int prio
)
318 struct rb_node
**p
= &root
->rb_node
, *parent
= NULL
;
323 c
= rb_entry(parent
, struct htb_class
, node
[prio
]);
325 if (cl
->classid
> c
->classid
)
326 p
= &parent
->rb_right
;
328 p
= &parent
->rb_left
;
330 rb_link_node(&cl
->node
[prio
], parent
, p
);
331 rb_insert_color(&cl
->node
[prio
], root
);
335 * htb_add_to_wait_tree - adds class to the event queue with delay
337 * The class is added to priority event queue to indicate that class will
338 * change its mode in cl->pq_key microseconds. Make sure that class is not
339 * already in the queue.
341 static void htb_add_to_wait_tree(struct htb_sched
*q
,
342 struct htb_class
*cl
, long delay
)
344 struct rb_node
**p
= &q
->wait_pq
[cl
->level
].rb_node
, *parent
= NULL
;
346 cl
->pq_key
= q
->jiffies
+ PSCHED_US2JIFFIE(delay
);
347 if (cl
->pq_key
== q
->jiffies
)
350 /* update the nearest event cache */
351 if (time_after(q
->near_ev_cache
[cl
->level
], cl
->pq_key
))
352 q
->near_ev_cache
[cl
->level
] = cl
->pq_key
;
357 c
= rb_entry(parent
, struct htb_class
, pq_node
);
358 if (time_after_eq(cl
->pq_key
, c
->pq_key
))
359 p
= &parent
->rb_right
;
361 p
= &parent
->rb_left
;
363 rb_link_node(&cl
->pq_node
, parent
, p
);
364 rb_insert_color(&cl
->pq_node
, &q
->wait_pq
[cl
->level
]);
368 * htb_next_rb_node - finds next node in binary tree
370 * When we are past last key we return NULL.
371 * Average complexity is 2 steps per call.
373 static inline void htb_next_rb_node(struct rb_node
**n
)
379 * htb_add_class_to_row - add class to its row
381 * The class is added to row at priorities marked in mask.
382 * It does nothing if mask == 0.
384 static inline void htb_add_class_to_row(struct htb_sched
*q
,
385 struct htb_class
*cl
, int mask
)
387 q
->row_mask
[cl
->level
] |= mask
;
389 int prio
= ffz(~mask
);
390 mask
&= ~(1 << prio
);
391 htb_add_to_id_tree(q
->row
[cl
->level
] + prio
, cl
, prio
);
395 /* If this triggers, it is a bug in this code, but it need not be fatal */
396 static void htb_safe_rb_erase(struct rb_node
*rb
, struct rb_root
*root
)
398 if (RB_EMPTY_NODE(rb
)) {
408 * htb_remove_class_from_row - removes class from its row
410 * The class is removed from row at priorities marked in mask.
411 * It does nothing if mask == 0.
413 static inline void htb_remove_class_from_row(struct htb_sched
*q
,
414 struct htb_class
*cl
, int mask
)
419 int prio
= ffz(~mask
);
421 mask
&= ~(1 << prio
);
422 if (q
->ptr
[cl
->level
][prio
] == cl
->node
+ prio
)
423 htb_next_rb_node(q
->ptr
[cl
->level
] + prio
);
425 htb_safe_rb_erase(cl
->node
+ prio
, q
->row
[cl
->level
] + prio
);
426 if (!q
->row
[cl
->level
][prio
].rb_node
)
429 q
->row_mask
[cl
->level
] &= ~m
;
433 * htb_activate_prios - creates active classe's feed chain
435 * The class is connected to ancestors and/or appropriate rows
436 * for priorities it is participating on. cl->cmode must be new
437 * (activated) mode. It does nothing if cl->prio_activity == 0.
439 static void htb_activate_prios(struct htb_sched
*q
, struct htb_class
*cl
)
441 struct htb_class
*p
= cl
->parent
;
442 long m
, mask
= cl
->prio_activity
;
444 while (cl
->cmode
== HTB_MAY_BORROW
&& p
&& mask
) {
450 if (p
->un
.inner
.feed
[prio
].rb_node
)
451 /* parent already has its feed in use so that
452 reset bit in mask as parent is already ok */
453 mask
&= ~(1 << prio
);
455 htb_add_to_id_tree(p
->un
.inner
.feed
+ prio
, cl
, prio
);
457 p
->prio_activity
|= mask
;
462 if (cl
->cmode
== HTB_CAN_SEND
&& mask
)
463 htb_add_class_to_row(q
, cl
, mask
);
467 * htb_deactivate_prios - remove class from feed chain
469 * cl->cmode must represent old mode (before deactivation). It does
470 * nothing if cl->prio_activity == 0. Class is removed from all feed
473 static void htb_deactivate_prios(struct htb_sched
*q
, struct htb_class
*cl
)
475 struct htb_class
*p
= cl
->parent
;
476 long m
, mask
= cl
->prio_activity
;
478 while (cl
->cmode
== HTB_MAY_BORROW
&& p
&& mask
) {
485 if (p
->un
.inner
.ptr
[prio
] == cl
->node
+ prio
) {
486 /* we are removing child which is pointed to from
487 parent feed - forget the pointer but remember
489 p
->un
.inner
.last_ptr_id
[prio
] = cl
->classid
;
490 p
->un
.inner
.ptr
[prio
] = NULL
;
493 htb_safe_rb_erase(cl
->node
+ prio
, p
->un
.inner
.feed
+ prio
);
495 if (!p
->un
.inner
.feed
[prio
].rb_node
)
499 p
->prio_activity
&= ~mask
;
504 if (cl
->cmode
== HTB_CAN_SEND
&& mask
)
505 htb_remove_class_from_row(q
, cl
, mask
);
509 static inline long htb_lowater(const struct htb_class
*cl
)
511 return cl
->cmode
!= HTB_CANT_SEND
? -cl
->cbuffer
: 0;
513 static inline long htb_hiwater(const struct htb_class
*cl
)
515 return cl
->cmode
== HTB_CAN_SEND
? -cl
->buffer
: 0;
518 #define htb_lowater(cl) (0)
519 #define htb_hiwater(cl) (0)
523 * htb_class_mode - computes and returns current class mode
525 * It computes cl's mode at time cl->t_c+diff and returns it. If mode
526 * is not HTB_CAN_SEND then cl->pq_key is updated to time difference
527 * from now to time when cl will change its state.
528 * Also it is worth to note that class mode doesn't change simply
529 * at cl->{c,}tokens == 0 but there can rather be hysteresis of
530 * 0 .. -cl->{c,}buffer range. It is meant to limit number of
531 * mode transitions per time unit. The speed gain is about 1/6.
533 static inline enum htb_cmode
534 htb_class_mode(struct htb_class
*cl
, long *diff
)
538 if ((toks
= (cl
->ctokens
+ *diff
)) < htb_lowater(cl
)) {
540 return HTB_CANT_SEND
;
543 if ((toks
= (cl
->tokens
+ *diff
)) >= htb_hiwater(cl
))
547 return HTB_MAY_BORROW
;
551 * htb_change_class_mode - changes classe's mode
553 * This should be the only way how to change classe's mode under normal
554 * cirsumstances. Routine will update feed lists linkage, change mode
555 * and add class to the wait event queue if appropriate. New mode should
556 * be different from old one and cl->pq_key has to be valid if changing
557 * to mode other than HTB_CAN_SEND (see htb_add_to_wait_tree).
560 htb_change_class_mode(struct htb_sched
*q
, struct htb_class
*cl
, long *diff
)
562 enum htb_cmode new_mode
= htb_class_mode(cl
, diff
);
564 if (new_mode
== cl
->cmode
)
567 if (cl
->prio_activity
) { /* not necessary: speed optimization */
568 if (cl
->cmode
!= HTB_CANT_SEND
)
569 htb_deactivate_prios(q
, cl
);
570 cl
->cmode
= new_mode
;
571 if (new_mode
!= HTB_CANT_SEND
)
572 htb_activate_prios(q
, cl
);
574 cl
->cmode
= new_mode
;
578 * htb_activate - inserts leaf cl into appropriate active feeds
580 * Routine learns (new) priority of leaf and activates feed chain
581 * for the prio. It can be called on already active leaf safely.
582 * It also adds leaf into droplist.
584 static inline void htb_activate(struct htb_sched
*q
, struct htb_class
*cl
)
586 BUG_TRAP(!cl
->level
&& cl
->un
.leaf
.q
&& cl
->un
.leaf
.q
->q
.qlen
);
588 if (!cl
->prio_activity
) {
589 cl
->prio_activity
= 1 << (cl
->un
.leaf
.aprio
= cl
->un
.leaf
.prio
);
590 htb_activate_prios(q
, cl
);
591 list_add_tail(&cl
->un
.leaf
.drop_list
,
592 q
->drops
+ cl
->un
.leaf
.aprio
);
597 * htb_deactivate - remove leaf cl from active feeds
599 * Make sure that leaf is active. In the other words it can't be called
600 * with non-active leaf. It also removes class from the drop list.
602 static inline void htb_deactivate(struct htb_sched
*q
, struct htb_class
*cl
)
604 BUG_TRAP(cl
->prio_activity
);
606 htb_deactivate_prios(q
, cl
);
607 cl
->prio_activity
= 0;
608 list_del_init(&cl
->un
.leaf
.drop_list
);
611 static int htb_enqueue(struct sk_buff
*skb
, struct Qdisc
*sch
)
614 struct htb_sched
*q
= qdisc_priv(sch
);
615 struct htb_class
*cl
= htb_classify(skb
, sch
, &ret
);
617 if (cl
== HTB_DIRECT
) {
618 /* enqueue to helper queue */
619 if (q
->direct_queue
.qlen
< q
->direct_qlen
) {
620 __skb_queue_tail(&q
->direct_queue
, skb
);
625 return NET_XMIT_DROP
;
627 #ifdef CONFIG_NET_CLS_ACT
629 if (ret
== NET_XMIT_BYPASS
)
634 } else if (cl
->un
.leaf
.q
->enqueue(skb
, cl
->un
.leaf
.q
) !=
638 return NET_XMIT_DROP
;
640 cl
->bstats
.packets
++;
641 cl
->bstats
.bytes
+= skb
->len
;
646 sch
->bstats
.packets
++;
647 sch
->bstats
.bytes
+= skb
->len
;
648 return NET_XMIT_SUCCESS
;
651 /* TODO: requeuing packet charges it to policers again !! */
652 static int htb_requeue(struct sk_buff
*skb
, struct Qdisc
*sch
)
654 struct htb_sched
*q
= qdisc_priv(sch
);
655 int ret
= NET_XMIT_SUCCESS
;
656 struct htb_class
*cl
= htb_classify(skb
, sch
, &ret
);
657 struct sk_buff
*tskb
;
659 if (cl
== HTB_DIRECT
|| !cl
) {
660 /* enqueue to helper queue */
661 if (q
->direct_queue
.qlen
< q
->direct_qlen
&& cl
) {
662 __skb_queue_head(&q
->direct_queue
, skb
);
664 __skb_queue_head(&q
->direct_queue
, skb
);
665 tskb
= __skb_dequeue_tail(&q
->direct_queue
);
670 } else if (cl
->un
.leaf
.q
->ops
->requeue(skb
, cl
->un
.leaf
.q
) !=
674 return NET_XMIT_DROP
;
679 sch
->qstats
.requeues
++;
680 return NET_XMIT_SUCCESS
;
683 static void htb_timer(unsigned long arg
)
685 struct Qdisc
*sch
= (struct Qdisc
*)arg
;
686 sch
->flags
&= ~TCQ_F_THROTTLED
;
688 netif_schedule(sch
->dev
);
692 #define RT_GEN(D,R) R+=D-(R/HTB_EWMAC);D=0
693 static void htb_rate_timer(unsigned long arg
)
695 struct Qdisc
*sch
= (struct Qdisc
*)arg
;
696 struct htb_sched
*q
= qdisc_priv(sch
);
697 struct hlist_node
*p
;
698 struct htb_class
*cl
;
701 /* lock queue so that we can muck with it */
702 spin_lock_bh(&sch
->dev
->queue_lock
);
704 q
->rttim
.expires
= jiffies
+ HZ
;
705 add_timer(&q
->rttim
);
707 /* scan and recompute one bucket at time */
708 if (++q
->recmp_bucket
>= HTB_HSIZE
)
711 hlist_for_each_entry(cl
,p
, q
->hash
+ q
->recmp_bucket
, hlist
) {
712 RT_GEN(cl
->sum_bytes
, cl
->rate_bytes
);
713 RT_GEN(cl
->sum_packets
, cl
->rate_packets
);
715 spin_unlock_bh(&sch
->dev
->queue_lock
);
720 * htb_charge_class - charges amount "bytes" to leaf and ancestors
722 * Routine assumes that packet "bytes" long was dequeued from leaf cl
723 * borrowing from "level". It accounts bytes to ceil leaky bucket for
724 * leaf and all ancestors and to rate bucket for ancestors at levels
725 * "level" and higher. It also handles possible change of mode resulting
726 * from the update. Note that mode can also increase here (MAY_BORROW to
727 * CAN_SEND) because we can use more precise clock that event queue here.
728 * In such case we remove class from event queue first.
730 static void htb_charge_class(struct htb_sched
*q
, struct htb_class
*cl
,
731 int level
, int bytes
)
734 enum htb_cmode old_mode
;
736 #define HTB_ACCNT(T,B,R) toks = diff + cl->T; \
737 if (toks > cl->B) toks = cl->B; \
738 toks -= L2T(cl, cl->R, bytes); \
739 if (toks <= -cl->mbuffer) toks = 1-cl->mbuffer; \
743 diff
= PSCHED_TDIFF_SAFE(q
->now
, cl
->t_c
, (u32
) cl
->mbuffer
);
744 if (cl
->level
>= level
) {
745 if (cl
->level
== level
)
747 HTB_ACCNT(tokens
, buffer
, rate
);
749 cl
->xstats
.borrows
++;
750 cl
->tokens
+= diff
; /* we moved t_c; update tokens */
752 HTB_ACCNT(ctokens
, cbuffer
, ceil
);
755 old_mode
= cl
->cmode
;
757 htb_change_class_mode(q
, cl
, &diff
);
758 if (old_mode
!= cl
->cmode
) {
759 if (old_mode
!= HTB_CAN_SEND
)
760 htb_safe_rb_erase(&cl
->pq_node
, q
->wait_pq
+ cl
->level
);
761 if (cl
->cmode
!= HTB_CAN_SEND
)
762 htb_add_to_wait_tree(q
, cl
, diff
);
765 /* update rate counters */
766 cl
->sum_bytes
+= bytes
;
770 /* update byte stats except for leaves which are already updated */
772 cl
->bstats
.bytes
+= bytes
;
773 cl
->bstats
.packets
++;
780 * htb_do_events - make mode changes to classes at the level
782 * Scans event queue for pending events and applies them. Returns jiffies to
783 * next pending event (0 for no event in pq).
784 * Note: Aplied are events whose have cl->pq_key <= jiffies.
786 static long htb_do_events(struct htb_sched
*q
, int level
)
790 for (i
= 0; i
< 500; i
++) {
791 struct htb_class
*cl
;
793 struct rb_node
*p
= rb_first(&q
->wait_pq
[level
]);
798 cl
= rb_entry(p
, struct htb_class
, pq_node
);
799 if (time_after(cl
->pq_key
, q
->jiffies
)) {
800 return cl
->pq_key
- q
->jiffies
;
802 htb_safe_rb_erase(p
, q
->wait_pq
+ level
);
803 diff
= PSCHED_TDIFF_SAFE(q
->now
, cl
->t_c
, (u32
) cl
->mbuffer
);
804 htb_change_class_mode(q
, cl
, &diff
);
805 if (cl
->cmode
!= HTB_CAN_SEND
)
806 htb_add_to_wait_tree(q
, cl
, diff
);
809 printk(KERN_WARNING
"htb: too many events !\n");
813 /* Returns class->node+prio from id-tree where classe's id is >= id. NULL
814 is no such one exists. */
815 static struct rb_node
*htb_id_find_next_upper(int prio
, struct rb_node
*n
,
818 struct rb_node
*r
= NULL
;
820 struct htb_class
*cl
=
821 rb_entry(n
, struct htb_class
, node
[prio
]);
822 if (id
== cl
->classid
)
825 if (id
> cl
->classid
) {
836 * htb_lookup_leaf - returns next leaf class in DRR order
838 * Find leaf where current feed pointers points to.
840 static struct htb_class
*htb_lookup_leaf(struct rb_root
*tree
, int prio
,
841 struct rb_node
**pptr
, u32
* pid
)
845 struct rb_node
*root
;
846 struct rb_node
**pptr
;
848 } stk
[TC_HTB_MAXDEPTH
], *sp
= stk
;
850 BUG_TRAP(tree
->rb_node
);
851 sp
->root
= tree
->rb_node
;
855 for (i
= 0; i
< 65535; i
++) {
856 if (!*sp
->pptr
&& *sp
->pid
) {
857 /* ptr was invalidated but id is valid - try to recover
858 the original or next ptr */
860 htb_id_find_next_upper(prio
, sp
->root
, *sp
->pid
);
862 *sp
->pid
= 0; /* ptr is valid now so that remove this hint as it
863 can become out of date quickly */
864 if (!*sp
->pptr
) { /* we are at right end; rewind & go up */
865 *sp
->pptr
= sp
->root
;
866 while ((*sp
->pptr
)->rb_left
)
867 *sp
->pptr
= (*sp
->pptr
)->rb_left
;
873 htb_next_rb_node(sp
->pptr
);
876 struct htb_class
*cl
;
877 cl
= rb_entry(*sp
->pptr
, struct htb_class
, node
[prio
]);
880 (++sp
)->root
= cl
->un
.inner
.feed
[prio
].rb_node
;
881 sp
->pptr
= cl
->un
.inner
.ptr
+ prio
;
882 sp
->pid
= cl
->un
.inner
.last_ptr_id
+ prio
;
889 /* dequeues packet at given priority and level; call only if
890 you are sure that there is active class at prio/level */
891 static struct sk_buff
*htb_dequeue_tree(struct htb_sched
*q
, int prio
,
894 struct sk_buff
*skb
= NULL
;
895 struct htb_class
*cl
, *start
;
896 /* look initial class up in the row */
897 start
= cl
= htb_lookup_leaf(q
->row
[level
] + prio
, prio
,
898 q
->ptr
[level
] + prio
,
899 q
->last_ptr_id
[level
] + prio
);
907 /* class can be empty - it is unlikely but can be true if leaf
908 qdisc drops packets in enqueue routine or if someone used
909 graft operation on the leaf since last dequeue;
910 simply deactivate and skip such class */
911 if (unlikely(cl
->un
.leaf
.q
->q
.qlen
== 0)) {
912 struct htb_class
*next
;
913 htb_deactivate(q
, cl
);
915 /* row/level might become empty */
916 if ((q
->row_mask
[level
] & (1 << prio
)) == 0)
919 next
= htb_lookup_leaf(q
->row
[level
] + prio
,
920 prio
, q
->ptr
[level
] + prio
,
921 q
->last_ptr_id
[level
] + prio
);
923 if (cl
== start
) /* fix start if we just deleted it */
929 skb
= cl
->un
.leaf
.q
->dequeue(cl
->un
.leaf
.q
);
930 if (likely(skb
!= NULL
))
934 "htb: class %X isn't work conserving ?!\n",
939 htb_next_rb_node((level
? cl
->parent
->un
.inner
.ptr
: q
->
941 cl
= htb_lookup_leaf(q
->row
[level
] + prio
, prio
,
942 q
->ptr
[level
] + prio
,
943 q
->last_ptr_id
[level
] + prio
);
945 } while (cl
!= start
);
947 if (likely(skb
!= NULL
)) {
948 if ((cl
->un
.leaf
.deficit
[level
] -= skb
->len
) < 0) {
949 cl
->un
.leaf
.deficit
[level
] += cl
->un
.leaf
.quantum
;
950 htb_next_rb_node((level
? cl
->parent
->un
.inner
.ptr
: q
->
953 /* this used to be after charge_class but this constelation
954 gives us slightly better performance */
955 if (!cl
->un
.leaf
.q
->q
.qlen
)
956 htb_deactivate(q
, cl
);
957 htb_charge_class(q
, cl
, level
, skb
->len
);
962 static void htb_delay_by(struct Qdisc
*sch
, long delay
)
964 struct htb_sched
*q
= qdisc_priv(sch
);
967 if (unlikely(delay
> 5 * HZ
)) {
969 printk(KERN_INFO
"HTB delay %ld > 5sec\n", delay
);
972 /* why don't use jiffies here ? because expires can be in past */
973 mod_timer(&q
->timer
, q
->jiffies
+ delay
);
974 sch
->flags
|= TCQ_F_THROTTLED
;
975 sch
->qstats
.overlimits
++;
978 static struct sk_buff
*htb_dequeue(struct Qdisc
*sch
)
980 struct sk_buff
*skb
= NULL
;
981 struct htb_sched
*q
= qdisc_priv(sch
);
985 q
->jiffies
= jiffies
;
987 /* try to dequeue direct packets as high prio (!) to minimize cpu work */
988 skb
= __skb_dequeue(&q
->direct_queue
);
990 sch
->flags
&= ~TCQ_F_THROTTLED
;
997 PSCHED_GET_TIME(q
->now
);
999 min_delay
= LONG_MAX
;
1001 for (level
= 0; level
< TC_HTB_MAXDEPTH
; level
++) {
1002 /* common case optimization - skip event handler quickly */
1005 if (time_after_eq(q
->jiffies
, q
->near_ev_cache
[level
])) {
1006 delay
= htb_do_events(q
, level
);
1007 q
->near_ev_cache
[level
] =
1008 q
->jiffies
+ (delay
? delay
: HZ
);
1010 delay
= q
->near_ev_cache
[level
] - q
->jiffies
;
1012 if (delay
&& min_delay
> delay
)
1014 m
= ~q
->row_mask
[level
];
1015 while (m
!= (int)(-1)) {
1018 skb
= htb_dequeue_tree(q
, prio
, level
);
1019 if (likely(skb
!= NULL
)) {
1021 sch
->flags
&= ~TCQ_F_THROTTLED
;
1026 htb_delay_by(sch
, min_delay
> 5 * HZ
? 5 * HZ
: min_delay
);
1031 /* try to drop from each class (by prio) until one succeed */
1032 static unsigned int htb_drop(struct Qdisc
*sch
)
1034 struct htb_sched
*q
= qdisc_priv(sch
);
1037 for (prio
= TC_HTB_NUMPRIO
- 1; prio
>= 0; prio
--) {
1038 struct list_head
*p
;
1039 list_for_each(p
, q
->drops
+ prio
) {
1040 struct htb_class
*cl
= list_entry(p
, struct htb_class
,
1043 if (cl
->un
.leaf
.q
->ops
->drop
&&
1044 (len
= cl
->un
.leaf
.q
->ops
->drop(cl
->un
.leaf
.q
))) {
1046 if (!cl
->un
.leaf
.q
->q
.qlen
)
1047 htb_deactivate(q
, cl
);
1055 /* reset all classes */
1056 /* always caled under BH & queue lock */
1057 static void htb_reset(struct Qdisc
*sch
)
1059 struct htb_sched
*q
= qdisc_priv(sch
);
1062 for (i
= 0; i
< HTB_HSIZE
; i
++) {
1063 struct hlist_node
*p
;
1064 struct htb_class
*cl
;
1066 hlist_for_each_entry(cl
, p
, q
->hash
+ i
, hlist
) {
1068 memset(&cl
->un
.inner
, 0, sizeof(cl
->un
.inner
));
1071 qdisc_reset(cl
->un
.leaf
.q
);
1072 INIT_LIST_HEAD(&cl
->un
.leaf
.drop_list
);
1074 cl
->prio_activity
= 0;
1075 cl
->cmode
= HTB_CAN_SEND
;
1079 sch
->flags
&= ~TCQ_F_THROTTLED
;
1080 del_timer(&q
->timer
);
1081 __skb_queue_purge(&q
->direct_queue
);
1083 memset(q
->row
, 0, sizeof(q
->row
));
1084 memset(q
->row_mask
, 0, sizeof(q
->row_mask
));
1085 memset(q
->wait_pq
, 0, sizeof(q
->wait_pq
));
1086 memset(q
->ptr
, 0, sizeof(q
->ptr
));
1087 for (i
= 0; i
< TC_HTB_NUMPRIO
; i
++)
1088 INIT_LIST_HEAD(q
->drops
+ i
);
1091 static int htb_init(struct Qdisc
*sch
, struct rtattr
*opt
)
1093 struct htb_sched
*q
= qdisc_priv(sch
);
1094 struct rtattr
*tb
[TCA_HTB_INIT
];
1095 struct tc_htb_glob
*gopt
;
1097 if (!opt
|| rtattr_parse_nested(tb
, TCA_HTB_INIT
, opt
) ||
1098 tb
[TCA_HTB_INIT
- 1] == NULL
||
1099 RTA_PAYLOAD(tb
[TCA_HTB_INIT
- 1]) < sizeof(*gopt
)) {
1100 printk(KERN_ERR
"HTB: hey probably you have bad tc tool ?\n");
1103 gopt
= RTA_DATA(tb
[TCA_HTB_INIT
- 1]);
1104 if (gopt
->version
!= HTB_VER
>> 16) {
1106 "HTB: need tc/htb version %d (minor is %d), you have %d\n",
1107 HTB_VER
>> 16, HTB_VER
& 0xffff, gopt
->version
);
1111 INIT_LIST_HEAD(&q
->root
);
1112 for (i
= 0; i
< HTB_HSIZE
; i
++)
1113 INIT_HLIST_HEAD(q
->hash
+ i
);
1114 for (i
= 0; i
< TC_HTB_NUMPRIO
; i
++)
1115 INIT_LIST_HEAD(q
->drops
+ i
);
1117 init_timer(&q
->timer
);
1118 skb_queue_head_init(&q
->direct_queue
);
1120 q
->direct_qlen
= sch
->dev
->tx_queue_len
;
1121 if (q
->direct_qlen
< 2) /* some devices have zero tx_queue_len */
1123 q
->timer
.function
= htb_timer
;
1124 q
->timer
.data
= (unsigned long)sch
;
1127 init_timer(&q
->rttim
);
1128 q
->rttim
.function
= htb_rate_timer
;
1129 q
->rttim
.data
= (unsigned long)sch
;
1130 q
->rttim
.expires
= jiffies
+ HZ
;
1131 add_timer(&q
->rttim
);
1133 if ((q
->rate2quantum
= gopt
->rate2quantum
) < 1)
1134 q
->rate2quantum
= 1;
1135 q
->defcls
= gopt
->defcls
;
1140 static int htb_dump(struct Qdisc
*sch
, struct sk_buff
*skb
)
1142 struct htb_sched
*q
= qdisc_priv(sch
);
1143 unsigned char *b
= skb
->tail
;
1145 struct tc_htb_glob gopt
;
1146 spin_lock_bh(&sch
->dev
->queue_lock
);
1147 gopt
.direct_pkts
= q
->direct_pkts
;
1149 gopt
.version
= HTB_VER
;
1150 gopt
.rate2quantum
= q
->rate2quantum
;
1151 gopt
.defcls
= q
->defcls
;
1153 rta
= (struct rtattr
*)b
;
1154 RTA_PUT(skb
, TCA_OPTIONS
, 0, NULL
);
1155 RTA_PUT(skb
, TCA_HTB_INIT
, sizeof(gopt
), &gopt
);
1156 rta
->rta_len
= skb
->tail
- b
;
1157 spin_unlock_bh(&sch
->dev
->queue_lock
);
1160 spin_unlock_bh(&sch
->dev
->queue_lock
);
1161 skb_trim(skb
, skb
->tail
- skb
->data
);
1165 static int htb_dump_class(struct Qdisc
*sch
, unsigned long arg
,
1166 struct sk_buff
*skb
, struct tcmsg
*tcm
)
1168 struct htb_class
*cl
= (struct htb_class
*)arg
;
1169 unsigned char *b
= skb
->tail
;
1171 struct tc_htb_opt opt
;
1173 spin_lock_bh(&sch
->dev
->queue_lock
);
1174 tcm
->tcm_parent
= cl
->parent
? cl
->parent
->classid
: TC_H_ROOT
;
1175 tcm
->tcm_handle
= cl
->classid
;
1176 if (!cl
->level
&& cl
->un
.leaf
.q
)
1177 tcm
->tcm_info
= cl
->un
.leaf
.q
->handle
;
1179 rta
= (struct rtattr
*)b
;
1180 RTA_PUT(skb
, TCA_OPTIONS
, 0, NULL
);
1182 memset(&opt
, 0, sizeof(opt
));
1184 opt
.rate
= cl
->rate
->rate
;
1185 opt
.buffer
= cl
->buffer
;
1186 opt
.ceil
= cl
->ceil
->rate
;
1187 opt
.cbuffer
= cl
->cbuffer
;
1188 opt
.quantum
= cl
->un
.leaf
.quantum
;
1189 opt
.prio
= cl
->un
.leaf
.prio
;
1190 opt
.level
= cl
->level
;
1191 RTA_PUT(skb
, TCA_HTB_PARMS
, sizeof(opt
), &opt
);
1192 rta
->rta_len
= skb
->tail
- b
;
1193 spin_unlock_bh(&sch
->dev
->queue_lock
);
1196 spin_unlock_bh(&sch
->dev
->queue_lock
);
1197 skb_trim(skb
, b
- skb
->data
);
1202 htb_dump_class_stats(struct Qdisc
*sch
, unsigned long arg
, struct gnet_dump
*d
)
1204 struct htb_class
*cl
= (struct htb_class
*)arg
;
1207 cl
->rate_est
.bps
= cl
->rate_bytes
/ (HTB_EWMAC
* HTB_HSIZE
);
1208 cl
->rate_est
.pps
= cl
->rate_packets
/ (HTB_EWMAC
* HTB_HSIZE
);
1211 if (!cl
->level
&& cl
->un
.leaf
.q
)
1212 cl
->qstats
.qlen
= cl
->un
.leaf
.q
->q
.qlen
;
1213 cl
->xstats
.tokens
= cl
->tokens
;
1214 cl
->xstats
.ctokens
= cl
->ctokens
;
1216 if (gnet_stats_copy_basic(d
, &cl
->bstats
) < 0 ||
1217 gnet_stats_copy_rate_est(d
, &cl
->rate_est
) < 0 ||
1218 gnet_stats_copy_queue(d
, &cl
->qstats
) < 0)
1221 return gnet_stats_copy_app(d
, &cl
->xstats
, sizeof(cl
->xstats
));
1224 static int htb_graft(struct Qdisc
*sch
, unsigned long arg
, struct Qdisc
*new,
1227 struct htb_class
*cl
= (struct htb_class
*)arg
;
1229 if (cl
&& !cl
->level
) {
1231 (new = qdisc_create_dflt(sch
->dev
, &pfifo_qdisc_ops
,
1236 if ((*old
= xchg(&cl
->un
.leaf
.q
, new)) != NULL
) {
1237 qdisc_tree_decrease_qlen(*old
, (*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 void htb_qlen_notify(struct Qdisc
*sch
, unsigned long arg
)
1254 struct htb_class
*cl
= (struct htb_class
*)arg
;
1256 if (cl
->un
.leaf
.q
->q
.qlen
== 0)
1257 htb_deactivate(qdisc_priv(sch
), cl
);
1260 static unsigned long htb_get(struct Qdisc
*sch
, u32 classid
)
1262 struct htb_class
*cl
= htb_find(classid
, sch
);
1265 return (unsigned long)cl
;
1268 static void htb_destroy_filters(struct tcf_proto
**fl
)
1270 struct tcf_proto
*tp
;
1272 while ((tp
= *fl
) != NULL
) {
1278 static inline int htb_parent_last_child(struct htb_class
*cl
)
1281 /* the root class */
1284 if (!(cl
->parent
->children
.next
== &cl
->sibling
&&
1285 cl
->parent
->children
.prev
== &cl
->sibling
))
1286 /* not the last child */
1292 static void htb_parent_to_leaf(struct htb_class
*cl
, struct Qdisc
*new_q
)
1294 struct htb_class
*parent
= cl
->parent
;
1296 BUG_TRAP(!cl
->level
&& cl
->un
.leaf
.q
&& !cl
->prio_activity
);
1299 memset(&parent
->un
.inner
, 0, sizeof(parent
->un
.inner
));
1300 INIT_LIST_HEAD(&parent
->un
.leaf
.drop_list
);
1301 parent
->un
.leaf
.q
= new_q
? new_q
: &noop_qdisc
;
1302 parent
->un
.leaf
.quantum
= parent
->quantum
;
1303 parent
->un
.leaf
.prio
= parent
->prio
;
1304 parent
->tokens
= parent
->buffer
;
1305 parent
->ctokens
= parent
->cbuffer
;
1306 PSCHED_GET_TIME(parent
->t_c
);
1307 parent
->cmode
= HTB_CAN_SEND
;
1310 static void htb_destroy_class(struct Qdisc
*sch
, struct htb_class
*cl
)
1312 struct htb_sched
*q
= qdisc_priv(sch
);
1315 BUG_TRAP(cl
->un
.leaf
.q
);
1316 qdisc_destroy(cl
->un
.leaf
.q
);
1318 qdisc_put_rtab(cl
->rate
);
1319 qdisc_put_rtab(cl
->ceil
);
1321 htb_destroy_filters(&cl
->filter_list
);
1323 while (!list_empty(&cl
->children
))
1324 htb_destroy_class(sch
, list_entry(cl
->children
.next
,
1325 struct htb_class
, sibling
));
1327 /* note: this delete may happen twice (see htb_delete) */
1328 hlist_del_init(&cl
->hlist
);
1329 list_del(&cl
->sibling
);
1331 if (cl
->prio_activity
)
1332 htb_deactivate(q
, cl
);
1334 if (cl
->cmode
!= HTB_CAN_SEND
)
1335 htb_safe_rb_erase(&cl
->pq_node
, q
->wait_pq
+ cl
->level
);
1340 /* always caled under BH & queue lock */
1341 static void htb_destroy(struct Qdisc
*sch
)
1343 struct htb_sched
*q
= qdisc_priv(sch
);
1345 del_timer_sync(&q
->timer
);
1347 del_timer_sync(&q
->rttim
);
1349 /* This line used to be after htb_destroy_class call below
1350 and surprisingly it worked in 2.4. But it must precede it
1351 because filter need its target class alive to be able to call
1352 unbind_filter on it (without Oops). */
1353 htb_destroy_filters(&q
->filter_list
);
1355 while (!list_empty(&q
->root
))
1356 htb_destroy_class(sch
, list_entry(q
->root
.next
,
1357 struct htb_class
, sibling
));
1359 __skb_queue_purge(&q
->direct_queue
);
1362 static int htb_delete(struct Qdisc
*sch
, unsigned long arg
)
1364 struct htb_sched
*q
= qdisc_priv(sch
);
1365 struct htb_class
*cl
= (struct htb_class
*)arg
;
1367 struct Qdisc
*new_q
= NULL
;
1370 // TODO: why don't allow to delete subtree ? references ? does
1371 // tc subsys quarantee us that in htb_destroy it holds no class
1372 // refs so that we can remove children safely there ?
1373 if (!list_empty(&cl
->children
) || cl
->filter_cnt
)
1376 if (!cl
->level
&& htb_parent_last_child(cl
)) {
1377 new_q
= qdisc_create_dflt(sch
->dev
, &pfifo_qdisc_ops
,
1378 cl
->parent
->classid
);
1384 /* delete from hash and active; remainder in destroy_class */
1385 hlist_del_init(&cl
->hlist
);
1388 qlen
= cl
->un
.leaf
.q
->q
.qlen
;
1389 qdisc_reset(cl
->un
.leaf
.q
);
1390 qdisc_tree_decrease_qlen(cl
->un
.leaf
.q
, qlen
);
1393 if (cl
->prio_activity
)
1394 htb_deactivate(q
, cl
);
1397 htb_parent_to_leaf(cl
, new_q
);
1399 if (--cl
->refcnt
== 0)
1400 htb_destroy_class(sch
, cl
);
1402 sch_tree_unlock(sch
);
1406 static void htb_put(struct Qdisc
*sch
, unsigned long arg
)
1408 struct htb_class
*cl
= (struct htb_class
*)arg
;
1410 if (--cl
->refcnt
== 0)
1411 htb_destroy_class(sch
, cl
);
1414 static int htb_change_class(struct Qdisc
*sch
, u32 classid
,
1415 u32 parentid
, struct rtattr
**tca
,
1419 struct htb_sched
*q
= qdisc_priv(sch
);
1420 struct htb_class
*cl
= (struct htb_class
*)*arg
, *parent
;
1421 struct rtattr
*opt
= tca
[TCA_OPTIONS
- 1];
1422 struct qdisc_rate_table
*rtab
= NULL
, *ctab
= NULL
;
1423 struct rtattr
*tb
[TCA_HTB_RTAB
];
1424 struct tc_htb_opt
*hopt
;
1426 /* extract all subattrs from opt attr */
1427 if (!opt
|| rtattr_parse_nested(tb
, TCA_HTB_RTAB
, opt
) ||
1428 tb
[TCA_HTB_PARMS
- 1] == NULL
||
1429 RTA_PAYLOAD(tb
[TCA_HTB_PARMS
- 1]) < sizeof(*hopt
))
1432 parent
= parentid
== TC_H_ROOT
? NULL
: htb_find(parentid
, sch
);
1434 hopt
= RTA_DATA(tb
[TCA_HTB_PARMS
- 1]);
1436 rtab
= qdisc_get_rtab(&hopt
->rate
, tb
[TCA_HTB_RTAB
- 1]);
1437 ctab
= qdisc_get_rtab(&hopt
->ceil
, tb
[TCA_HTB_CTAB
- 1]);
1441 if (!cl
) { /* new class */
1442 struct Qdisc
*new_q
;
1445 /* check for valid classid */
1446 if (!classid
|| TC_H_MAJ(classid
^ sch
->handle
)
1447 || htb_find(classid
, sch
))
1450 /* check maximal depth */
1451 if (parent
&& parent
->parent
&& parent
->parent
->level
< 2) {
1452 printk(KERN_ERR
"htb: tree is too deep\n");
1456 if ((cl
= kzalloc(sizeof(*cl
), GFP_KERNEL
)) == NULL
)
1460 INIT_LIST_HEAD(&cl
->sibling
);
1461 INIT_HLIST_NODE(&cl
->hlist
);
1462 INIT_LIST_HEAD(&cl
->children
);
1463 INIT_LIST_HEAD(&cl
->un
.leaf
.drop_list
);
1464 RB_CLEAR_NODE(&cl
->pq_node
);
1466 for (prio
= 0; prio
< TC_HTB_NUMPRIO
; prio
++)
1467 RB_CLEAR_NODE(&cl
->node
[prio
]);
1469 /* create leaf qdisc early because it uses kmalloc(GFP_KERNEL)
1470 so that can't be used inside of sch_tree_lock
1471 -- thanks to Karlis Peisenieks */
1472 new_q
= qdisc_create_dflt(sch
->dev
, &pfifo_qdisc_ops
, classid
);
1474 if (parent
&& !parent
->level
) {
1475 unsigned int qlen
= parent
->un
.leaf
.q
->q
.qlen
;
1477 /* turn parent into inner node */
1478 qdisc_reset(parent
->un
.leaf
.q
);
1479 qdisc_tree_decrease_qlen(parent
->un
.leaf
.q
, qlen
);
1480 qdisc_destroy(parent
->un
.leaf
.q
);
1481 if (parent
->prio_activity
)
1482 htb_deactivate(q
, parent
);
1484 /* remove from evt list because of level change */
1485 if (parent
->cmode
!= HTB_CAN_SEND
) {
1486 htb_safe_rb_erase(&parent
->pq_node
, q
->wait_pq
);
1487 parent
->cmode
= HTB_CAN_SEND
;
1489 parent
->level
= (parent
->parent
? parent
->parent
->level
1490 : TC_HTB_MAXDEPTH
) - 1;
1491 memset(&parent
->un
.inner
, 0, sizeof(parent
->un
.inner
));
1493 /* leaf (we) needs elementary qdisc */
1494 cl
->un
.leaf
.q
= new_q
? new_q
: &noop_qdisc
;
1496 cl
->classid
= classid
;
1497 cl
->parent
= parent
;
1499 /* set class to be in HTB_CAN_SEND state */
1500 cl
->tokens
= hopt
->buffer
;
1501 cl
->ctokens
= hopt
->cbuffer
;
1502 cl
->mbuffer
= PSCHED_JIFFIE2US(HZ
* 60); /* 1min */
1503 PSCHED_GET_TIME(cl
->t_c
);
1504 cl
->cmode
= HTB_CAN_SEND
;
1506 /* attach to the hash list and parent's family */
1507 hlist_add_head(&cl
->hlist
, q
->hash
+ htb_hash(classid
));
1508 list_add_tail(&cl
->sibling
,
1509 parent
? &parent
->children
: &q
->root
);
1513 /* it used to be a nasty bug here, we have to check that node
1514 is really leaf before changing cl->un.leaf ! */
1516 cl
->un
.leaf
.quantum
= rtab
->rate
.rate
/ q
->rate2quantum
;
1517 if (!hopt
->quantum
&& cl
->un
.leaf
.quantum
< 1000) {
1519 "HTB: quantum of class %X is small. Consider r2q change.\n",
1521 cl
->un
.leaf
.quantum
= 1000;
1523 if (!hopt
->quantum
&& cl
->un
.leaf
.quantum
> 200000) {
1525 "HTB: quantum of class %X is big. Consider r2q change.\n",
1527 cl
->un
.leaf
.quantum
= 200000;
1530 cl
->un
.leaf
.quantum
= hopt
->quantum
;
1531 if ((cl
->un
.leaf
.prio
= hopt
->prio
) >= TC_HTB_NUMPRIO
)
1532 cl
->un
.leaf
.prio
= TC_HTB_NUMPRIO
- 1;
1534 /* backup for htb_parent_to_leaf */
1535 cl
->quantum
= cl
->un
.leaf
.quantum
;
1536 cl
->prio
= cl
->un
.leaf
.prio
;
1539 cl
->buffer
= hopt
->buffer
;
1540 cl
->cbuffer
= hopt
->cbuffer
;
1542 qdisc_put_rtab(cl
->rate
);
1545 qdisc_put_rtab(cl
->ceil
);
1547 sch_tree_unlock(sch
);
1549 *arg
= (unsigned long)cl
;
1554 qdisc_put_rtab(rtab
);
1556 qdisc_put_rtab(ctab
);
1560 static struct tcf_proto
**htb_find_tcf(struct Qdisc
*sch
, unsigned long arg
)
1562 struct htb_sched
*q
= qdisc_priv(sch
);
1563 struct htb_class
*cl
= (struct htb_class
*)arg
;
1564 struct tcf_proto
**fl
= cl
? &cl
->filter_list
: &q
->filter_list
;
1569 static unsigned long htb_bind_filter(struct Qdisc
*sch
, unsigned long parent
,
1572 struct htb_sched
*q
= qdisc_priv(sch
);
1573 struct htb_class
*cl
= htb_find(classid
, sch
);
1575 /*if (cl && !cl->level) return 0;
1576 The line above used to be there to prevent attaching filters to
1577 leaves. But at least tc_index filter uses this just to get class
1578 for other reasons so that we have to allow for it.
1580 19.6.2002 As Werner explained it is ok - bind filter is just
1581 another way to "lock" the class - unlike "get" this lock can
1582 be broken by class during destroy IIUC.
1588 return (unsigned long)cl
;
1591 static void htb_unbind_filter(struct Qdisc
*sch
, unsigned long arg
)
1593 struct htb_sched
*q
= qdisc_priv(sch
);
1594 struct htb_class
*cl
= (struct htb_class
*)arg
;
1602 static void htb_walk(struct Qdisc
*sch
, struct qdisc_walker
*arg
)
1604 struct htb_sched
*q
= qdisc_priv(sch
);
1610 for (i
= 0; i
< HTB_HSIZE
; i
++) {
1611 struct hlist_node
*p
;
1612 struct htb_class
*cl
;
1614 hlist_for_each_entry(cl
, p
, q
->hash
+ i
, hlist
) {
1615 if (arg
->count
< arg
->skip
) {
1619 if (arg
->fn(sch
, (unsigned long)cl
, arg
) < 0) {
1628 static struct Qdisc_class_ops htb_class_ops
= {
1631 .qlen_notify
= htb_qlen_notify
,
1634 .change
= htb_change_class
,
1635 .delete = htb_delete
,
1637 .tcf_chain
= htb_find_tcf
,
1638 .bind_tcf
= htb_bind_filter
,
1639 .unbind_tcf
= htb_unbind_filter
,
1640 .dump
= htb_dump_class
,
1641 .dump_stats
= htb_dump_class_stats
,
1644 static struct Qdisc_ops htb_qdisc_ops
= {
1646 .cl_ops
= &htb_class_ops
,
1648 .priv_size
= sizeof(struct htb_sched
),
1649 .enqueue
= htb_enqueue
,
1650 .dequeue
= htb_dequeue
,
1651 .requeue
= htb_requeue
,
1655 .destroy
= htb_destroy
,
1656 .change
= NULL
/* htb_change */,
1658 .owner
= THIS_MODULE
,
1661 static int __init
htb_module_init(void)
1663 return register_qdisc(&htb_qdisc_ops
);
1665 static void __exit
htb_module_exit(void)
1667 unregister_qdisc(&htb_qdisc_ops
);
1670 module_init(htb_module_init
)
1671 module_exit(htb_module_exit
)
1672 MODULE_LICENSE("GPL");