| /* |
| * net/sched/sch_htb.c Hierarchical token bucket, feed tree version |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| * |
| * Authors: Martin Devera, <devik@cdi.cz> |
| * |
| * Credits (in time order) for older HTB versions: |
| * Stef Coene <stef.coene@docum.org> |
| * HTB support at LARTC mailing list |
| * Ondrej Kraus, <krauso@barr.cz> |
| * found missing INIT_QDISC(htb) |
| * Vladimir Smelhaus, Aamer Akhter, Bert Hubert |
| * helped a lot to locate nasty class stall bug |
| * Andi Kleen, Jamal Hadi, Bert Hubert |
| * code review and helpful comments on shaping |
| * Tomasz Wrona, <tw@eter.tym.pl> |
| * created test case so that I was able to fix nasty bug |
| * Wilfried Weissmann |
| * spotted bug in dequeue code and helped with fix |
| * Jiri Fojtasek |
| * fixed requeue routine |
| * and many others. thanks. |
| * |
| * $Id: sch_htb.c,v 1.25 2003/12/07 11:08:25 devik Exp devik $ |
| */ |
| #include <linux/module.h> |
| #include <linux/moduleparam.h> |
| #include <linux/types.h> |
| #include <linux/kernel.h> |
| #include <linux/string.h> |
| #include <linux/errno.h> |
| #include <linux/skbuff.h> |
| #include <linux/list.h> |
| #include <linux/compiler.h> |
| #include <linux/rbtree.h> |
| #include <net/netlink.h> |
| #include <net/pkt_sched.h> |
| |
| /* HTB algorithm. |
| Author: devik@cdi.cz |
| ======================================================================== |
| HTB is like TBF with multiple classes. It is also similar to CBQ because |
| it allows to assign priority to each class in hierarchy. |
| In fact it is another implementation of Floyd's formal sharing. |
| |
| Levels: |
| Each class is assigned level. Leaf has ALWAYS level 0 and root |
| classes have level TC_HTB_MAXDEPTH-1. Interior nodes has level |
| one less than their parent. |
| */ |
| |
| #define HTB_HSIZE 16 /* classid hash size */ |
| static int htb_hysteresis __read_mostly = 0; /* whether to use mode hysteresis for speedup */ |
| #define HTB_VER 0x30011 /* major must be matched with number suplied by TC as version */ |
| |
| #if HTB_VER >> 16 != TC_HTB_PROTOVER |
| #error "Mismatched sch_htb.c and pkt_sch.h" |
| #endif |
| |
| /* Module parameter and sysfs export */ |
| module_param (htb_hysteresis, int, 0640); |
| MODULE_PARM_DESC(htb_hysteresis, "Hysteresis mode, less CPU load, less accurate"); |
| |
| /* used internaly to keep status of single class */ |
| enum htb_cmode { |
| HTB_CANT_SEND, /* class can't send and can't borrow */ |
| HTB_MAY_BORROW, /* class can't send but may borrow */ |
| HTB_CAN_SEND /* class can send */ |
| }; |
| |
| /* interior & leaf nodes; props specific to leaves are marked L: */ |
| struct htb_class { |
| /* general class parameters */ |
| u32 classid; |
| struct gnet_stats_basic bstats; |
| struct gnet_stats_queue qstats; |
| struct gnet_stats_rate_est rate_est; |
| struct tc_htb_xstats xstats; /* our special stats */ |
| int refcnt; /* usage count of this class */ |
| |
| /* topology */ |
| int level; /* our level (see above) */ |
| struct htb_class *parent; /* parent class */ |
| struct hlist_node hlist; /* classid hash list item */ |
| struct list_head sibling; /* sibling list item */ |
| struct list_head children; /* children list */ |
| |
| union { |
| struct htb_class_leaf { |
| struct Qdisc *q; |
| int prio; |
| int aprio; |
| int quantum; |
| int deficit[TC_HTB_MAXDEPTH]; |
| struct list_head drop_list; |
| } leaf; |
| struct htb_class_inner { |
| struct rb_root feed[TC_HTB_NUMPRIO]; /* feed trees */ |
| struct rb_node *ptr[TC_HTB_NUMPRIO]; /* current class ptr */ |
| /* When class changes from state 1->2 and disconnects from |
| parent's feed then we lost ptr value and start from the |
| first child again. Here we store classid of the |
| last valid ptr (used when ptr is NULL). */ |
| u32 last_ptr_id[TC_HTB_NUMPRIO]; |
| } inner; |
| } un; |
| struct rb_node node[TC_HTB_NUMPRIO]; /* node for self or feed tree */ |
| struct rb_node pq_node; /* node for event queue */ |
| psched_time_t pq_key; |
| |
| int prio_activity; /* for which prios are we active */ |
| enum htb_cmode cmode; /* current mode of the class */ |
| |
| /* class attached filters */ |
| struct tcf_proto *filter_list; |
| int filter_cnt; |
| |
| int warned; /* only one warning about non work conserving .. */ |
| |
| /* token bucket parameters */ |
| struct qdisc_rate_table *rate; /* rate table of the class itself */ |
| struct qdisc_rate_table *ceil; /* ceiling rate (limits borrows too) */ |
| long buffer, cbuffer; /* token bucket depth/rate */ |
| psched_tdiff_t mbuffer; /* max wait time */ |
| long tokens, ctokens; /* current number of tokens */ |
| psched_time_t t_c; /* checkpoint time */ |
| |
| int prio; /* For parent to leaf return possible here */ |
| int quantum; /* we do backup. Finally full replacement */ |
| /* of un.leaf originals should be done. */ |
| }; |
| |
| static inline long L2T(struct htb_class *cl, struct qdisc_rate_table *rate, |
| int size) |
| { |
| long result = qdisc_l2t(rate, size); |
| return result; |
| } |
| |
| struct htb_sched { |
| struct list_head root; /* root classes list */ |
| struct hlist_head hash[HTB_HSIZE]; /* hashed by classid */ |
| struct list_head drops[TC_HTB_NUMPRIO];/* active leaves (for drops) */ |
| |
| /* self list - roots of self generating tree */ |
| struct rb_root row[TC_HTB_MAXDEPTH][TC_HTB_NUMPRIO]; |
| int row_mask[TC_HTB_MAXDEPTH]; |
| struct rb_node *ptr[TC_HTB_MAXDEPTH][TC_HTB_NUMPRIO]; |
| u32 last_ptr_id[TC_HTB_MAXDEPTH][TC_HTB_NUMPRIO]; |
| |
| /* self wait list - roots of wait PQs per row */ |
| struct rb_root wait_pq[TC_HTB_MAXDEPTH]; |
| |
| /* time of nearest event per level (row) */ |
| psched_time_t near_ev_cache[TC_HTB_MAXDEPTH]; |
| |
| /* whether we hit non-work conserving class during this dequeue; we use */ |
| int nwc_hit; /* this to disable mindelay complaint in dequeue */ |
| |
| int defcls; /* class where unclassified flows go to */ |
| |
| /* filters for qdisc itself */ |
| struct tcf_proto *filter_list; |
| int filter_cnt; |
| |
| int rate2quantum; /* quant = rate / rate2quantum */ |
| psched_time_t now; /* cached dequeue time */ |
| struct qdisc_watchdog watchdog; |
| |
| /* non shaped skbs; let them go directly thru */ |
| struct sk_buff_head direct_queue; |
| int direct_qlen; /* max qlen of above */ |
| |
| long direct_pkts; |
| }; |
| |
| /* compute hash of size HTB_HSIZE for given handle */ |
| static inline int htb_hash(u32 h) |
| { |
| #if HTB_HSIZE != 16 |
| #error "Declare new hash for your HTB_HSIZE" |
| #endif |
| h ^= h >> 8; /* stolen from cbq_hash */ |
| h ^= h >> 4; |
| return h & 0xf; |
| } |
| |
| /* find class in global hash table using given handle */ |
| static inline struct htb_class *htb_find(u32 handle, struct Qdisc *sch) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| struct hlist_node *p; |
| struct htb_class *cl; |
| |
| if (TC_H_MAJ(handle) != sch->handle) |
| return NULL; |
| |
| hlist_for_each_entry(cl, p, q->hash + htb_hash(handle), hlist) { |
| if (cl->classid == handle) |
| return cl; |
| } |
| return NULL; |
| } |
| |
| /** |
| * htb_classify - classify a packet into class |
| * |
| * It returns NULL if the packet should be dropped or -1 if the packet |
| * should be passed directly thru. In all other cases leaf class is returned. |
| * We allow direct class selection by classid in priority. The we examine |
| * filters in qdisc and in inner nodes (if higher filter points to the inner |
| * node). If we end up with classid MAJOR:0 we enqueue the skb into special |
| * internal fifo (direct). These packets then go directly thru. If we still |
| * have no valid leaf we try to use MAJOR:default leaf. It still unsuccessfull |
| * then finish and return direct queue. |
| */ |
| #define HTB_DIRECT (struct htb_class*)-1 |
| |
| static struct htb_class *htb_classify(struct sk_buff *skb, struct Qdisc *sch, |
| int *qerr) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| struct htb_class *cl; |
| struct tcf_result res; |
| struct tcf_proto *tcf; |
| int result; |
| |
| /* allow to select class by setting skb->priority to valid classid; |
| note that nfmark can be used too by attaching filter fw with no |
| rules in it */ |
| if (skb->priority == sch->handle) |
| return HTB_DIRECT; /* X:0 (direct flow) selected */ |
| if ((cl = htb_find(skb->priority, sch)) != NULL && cl->level == 0) |
| return cl; |
| |
| *qerr = NET_XMIT_BYPASS; |
| tcf = q->filter_list; |
| while (tcf && (result = tc_classify(skb, tcf, &res)) >= 0) { |
| #ifdef CONFIG_NET_CLS_ACT |
| switch (result) { |
| case TC_ACT_QUEUED: |
| case TC_ACT_STOLEN: |
| *qerr = NET_XMIT_SUCCESS; |
| case TC_ACT_SHOT: |
| return NULL; |
| } |
| #endif |
| if ((cl = (void *)res.class) == NULL) { |
| if (res.classid == sch->handle) |
| return HTB_DIRECT; /* X:0 (direct flow) */ |
| if ((cl = htb_find(res.classid, sch)) == NULL) |
| break; /* filter selected invalid classid */ |
| } |
| if (!cl->level) |
| return cl; /* we hit leaf; return it */ |
| |
| /* we have got inner class; apply inner filter chain */ |
| tcf = cl->filter_list; |
| } |
| /* classification failed; try to use default class */ |
| cl = htb_find(TC_H_MAKE(TC_H_MAJ(sch->handle), q->defcls), sch); |
| if (!cl || cl->level) |
| return HTB_DIRECT; /* bad default .. this is safe bet */ |
| return cl; |
| } |
| |
| /** |
| * htb_add_to_id_tree - adds class to the round robin list |
| * |
| * Routine adds class to the list (actually tree) sorted by classid. |
| * Make sure that class is not already on such list for given prio. |
| */ |
| static void htb_add_to_id_tree(struct rb_root *root, |
| struct htb_class *cl, int prio) |
| { |
| struct rb_node **p = &root->rb_node, *parent = NULL; |
| |
| while (*p) { |
| struct htb_class *c; |
| parent = *p; |
| c = rb_entry(parent, struct htb_class, node[prio]); |
| |
| if (cl->classid > c->classid) |
| p = &parent->rb_right; |
| else |
| p = &parent->rb_left; |
| } |
| rb_link_node(&cl->node[prio], parent, p); |
| rb_insert_color(&cl->node[prio], root); |
| } |
| |
| /** |
| * htb_add_to_wait_tree - adds class to the event queue with delay |
| * |
| * The class is added to priority event queue to indicate that class will |
| * change its mode in cl->pq_key microseconds. Make sure that class is not |
| * already in the queue. |
| */ |
| static void htb_add_to_wait_tree(struct htb_sched *q, |
| struct htb_class *cl, long delay) |
| { |
| struct rb_node **p = &q->wait_pq[cl->level].rb_node, *parent = NULL; |
| |
| cl->pq_key = q->now + delay; |
| if (cl->pq_key == q->now) |
| cl->pq_key++; |
| |
| /* update the nearest event cache */ |
| if (q->near_ev_cache[cl->level] > cl->pq_key) |
| q->near_ev_cache[cl->level] = cl->pq_key; |
| |
| while (*p) { |
| struct htb_class *c; |
| parent = *p; |
| c = rb_entry(parent, struct htb_class, pq_node); |
| if (cl->pq_key >= c->pq_key) |
| p = &parent->rb_right; |
| else |
| p = &parent->rb_left; |
| } |
| rb_link_node(&cl->pq_node, parent, p); |
| rb_insert_color(&cl->pq_node, &q->wait_pq[cl->level]); |
| } |
| |
| /** |
| * htb_next_rb_node - finds next node in binary tree |
| * |
| * When we are past last key we return NULL. |
| * Average complexity is 2 steps per call. |
| */ |
| static inline void htb_next_rb_node(struct rb_node **n) |
| { |
| *n = rb_next(*n); |
| } |
| |
| /** |
| * htb_add_class_to_row - add class to its row |
| * |
| * The class is added to row at priorities marked in mask. |
| * It does nothing if mask == 0. |
| */ |
| static inline void htb_add_class_to_row(struct htb_sched *q, |
| struct htb_class *cl, int mask) |
| { |
| q->row_mask[cl->level] |= mask; |
| while (mask) { |
| int prio = ffz(~mask); |
| mask &= ~(1 << prio); |
| htb_add_to_id_tree(q->row[cl->level] + prio, cl, prio); |
| } |
| } |
| |
| /* If this triggers, it is a bug in this code, but it need not be fatal */ |
| static void htb_safe_rb_erase(struct rb_node *rb, struct rb_root *root) |
| { |
| if (RB_EMPTY_NODE(rb)) { |
| WARN_ON(1); |
| } else { |
| rb_erase(rb, root); |
| RB_CLEAR_NODE(rb); |
| } |
| } |
| |
| |
| /** |
| * htb_remove_class_from_row - removes class from its row |
| * |
| * The class is removed from row at priorities marked in mask. |
| * It does nothing if mask == 0. |
| */ |
| static inline void htb_remove_class_from_row(struct htb_sched *q, |
| struct htb_class *cl, int mask) |
| { |
| int m = 0; |
| |
| while (mask) { |
| int prio = ffz(~mask); |
| |
| mask &= ~(1 << prio); |
| if (q->ptr[cl->level][prio] == cl->node + prio) |
| htb_next_rb_node(q->ptr[cl->level] + prio); |
| |
| htb_safe_rb_erase(cl->node + prio, q->row[cl->level] + prio); |
| if (!q->row[cl->level][prio].rb_node) |
| m |= 1 << prio; |
| } |
| q->row_mask[cl->level] &= ~m; |
| } |
| |
| /** |
| * htb_activate_prios - creates active classe's feed chain |
| * |
| * The class is connected to ancestors and/or appropriate rows |
| * for priorities it is participating on. cl->cmode must be new |
| * (activated) mode. It does nothing if cl->prio_activity == 0. |
| */ |
| static void htb_activate_prios(struct htb_sched *q, struct htb_class *cl) |
| { |
| struct htb_class *p = cl->parent; |
| long m, mask = cl->prio_activity; |
| |
| while (cl->cmode == HTB_MAY_BORROW && p && mask) { |
| m = mask; |
| while (m) { |
| int prio = ffz(~m); |
| m &= ~(1 << prio); |
| |
| if (p->un.inner.feed[prio].rb_node) |
| /* parent already has its feed in use so that |
| reset bit in mask as parent is already ok */ |
| mask &= ~(1 << prio); |
| |
| htb_add_to_id_tree(p->un.inner.feed + prio, cl, prio); |
| } |
| p->prio_activity |= mask; |
| cl = p; |
| p = cl->parent; |
| |
| } |
| if (cl->cmode == HTB_CAN_SEND && mask) |
| htb_add_class_to_row(q, cl, mask); |
| } |
| |
| /** |
| * htb_deactivate_prios - remove class from feed chain |
| * |
| * cl->cmode must represent old mode (before deactivation). It does |
| * nothing if cl->prio_activity == 0. Class is removed from all feed |
| * chains and rows. |
| */ |
| static void htb_deactivate_prios(struct htb_sched *q, struct htb_class *cl) |
| { |
| struct htb_class *p = cl->parent; |
| long m, mask = cl->prio_activity; |
| |
| while (cl->cmode == HTB_MAY_BORROW && p && mask) { |
| m = mask; |
| mask = 0; |
| while (m) { |
| int prio = ffz(~m); |
| m &= ~(1 << prio); |
| |
| if (p->un.inner.ptr[prio] == cl->node + prio) { |
| /* we are removing child which is pointed to from |
| parent feed - forget the pointer but remember |
| classid */ |
| p->un.inner.last_ptr_id[prio] = cl->classid; |
| p->un.inner.ptr[prio] = NULL; |
| } |
| |
| htb_safe_rb_erase(cl->node + prio, p->un.inner.feed + prio); |
| |
| if (!p->un.inner.feed[prio].rb_node) |
| mask |= 1 << prio; |
| } |
| |
| p->prio_activity &= ~mask; |
| cl = p; |
| p = cl->parent; |
| |
| } |
| if (cl->cmode == HTB_CAN_SEND && mask) |
| htb_remove_class_from_row(q, cl, mask); |
| } |
| |
| static inline long htb_lowater(const struct htb_class *cl) |
| { |
| if (htb_hysteresis) |
| return cl->cmode != HTB_CANT_SEND ? -cl->cbuffer : 0; |
| else |
| return 0; |
| } |
| static inline long htb_hiwater(const struct htb_class *cl) |
| { |
| if (htb_hysteresis) |
| return cl->cmode == HTB_CAN_SEND ? -cl->buffer : 0; |
| else |
| return 0; |
| } |
| |
| |
| /** |
| * htb_class_mode - computes and returns current class mode |
| * |
| * It computes cl's mode at time cl->t_c+diff and returns it. If mode |
| * is not HTB_CAN_SEND then cl->pq_key is updated to time difference |
| * from now to time when cl will change its state. |
| * Also it is worth to note that class mode doesn't change simply |
| * at cl->{c,}tokens == 0 but there can rather be hysteresis of |
| * 0 .. -cl->{c,}buffer range. It is meant to limit number of |
| * mode transitions per time unit. The speed gain is about 1/6. |
| */ |
| static inline enum htb_cmode |
| htb_class_mode(struct htb_class *cl, long *diff) |
| { |
| long toks; |
| |
| if ((toks = (cl->ctokens + *diff)) < htb_lowater(cl)) { |
| *diff = -toks; |
| return HTB_CANT_SEND; |
| } |
| |
| if ((toks = (cl->tokens + *diff)) >= htb_hiwater(cl)) |
| return HTB_CAN_SEND; |
| |
| *diff = -toks; |
| return HTB_MAY_BORROW; |
| } |
| |
| /** |
| * htb_change_class_mode - changes classe's mode |
| * |
| * This should be the only way how to change classe's mode under normal |
| * cirsumstances. Routine will update feed lists linkage, change mode |
| * and add class to the wait event queue if appropriate. New mode should |
| * be different from old one and cl->pq_key has to be valid if changing |
| * to mode other than HTB_CAN_SEND (see htb_add_to_wait_tree). |
| */ |
| static void |
| htb_change_class_mode(struct htb_sched *q, struct htb_class *cl, long *diff) |
| { |
| enum htb_cmode new_mode = htb_class_mode(cl, diff); |
| |
| if (new_mode == cl->cmode) |
| return; |
| |
| if (cl->prio_activity) { /* not necessary: speed optimization */ |
| if (cl->cmode != HTB_CANT_SEND) |
| htb_deactivate_prios(q, cl); |
| cl->cmode = new_mode; |
| if (new_mode != HTB_CANT_SEND) |
| htb_activate_prios(q, cl); |
| } else |
| cl->cmode = new_mode; |
| } |
| |
| /** |
| * htb_activate - inserts leaf cl into appropriate active feeds |
| * |
| * Routine learns (new) priority of leaf and activates feed chain |
| * for the prio. It can be called on already active leaf safely. |
| * It also adds leaf into droplist. |
| */ |
| static inline void htb_activate(struct htb_sched *q, struct htb_class *cl) |
| { |
| BUG_TRAP(!cl->level && cl->un.leaf.q && cl->un.leaf.q->q.qlen); |
| |
| if (!cl->prio_activity) { |
| cl->prio_activity = 1 << (cl->un.leaf.aprio = cl->un.leaf.prio); |
| htb_activate_prios(q, cl); |
| list_add_tail(&cl->un.leaf.drop_list, |
| q->drops + cl->un.leaf.aprio); |
| } |
| } |
| |
| /** |
| * htb_deactivate - remove leaf cl from active feeds |
| * |
| * Make sure that leaf is active. In the other words it can't be called |
| * with non-active leaf. It also removes class from the drop list. |
| */ |
| static inline void htb_deactivate(struct htb_sched *q, struct htb_class *cl) |
| { |
| BUG_TRAP(cl->prio_activity); |
| |
| htb_deactivate_prios(q, cl); |
| cl->prio_activity = 0; |
| list_del_init(&cl->un.leaf.drop_list); |
| } |
| |
| static int htb_enqueue(struct sk_buff *skb, struct Qdisc *sch) |
| { |
| int ret; |
| struct htb_sched *q = qdisc_priv(sch); |
| struct htb_class *cl = htb_classify(skb, sch, &ret); |
| |
| if (cl == HTB_DIRECT) { |
| /* enqueue to helper queue */ |
| if (q->direct_queue.qlen < q->direct_qlen) { |
| __skb_queue_tail(&q->direct_queue, skb); |
| q->direct_pkts++; |
| } else { |
| kfree_skb(skb); |
| sch->qstats.drops++; |
| return NET_XMIT_DROP; |
| } |
| #ifdef CONFIG_NET_CLS_ACT |
| } else if (!cl) { |
| if (ret == NET_XMIT_BYPASS) |
| sch->qstats.drops++; |
| kfree_skb(skb); |
| return ret; |
| #endif |
| } else if (cl->un.leaf.q->enqueue(skb, cl->un.leaf.q) != |
| NET_XMIT_SUCCESS) { |
| sch->qstats.drops++; |
| cl->qstats.drops++; |
| return NET_XMIT_DROP; |
| } else { |
| cl->bstats.packets += |
| skb_is_gso(skb)?skb_shinfo(skb)->gso_segs:1; |
| cl->bstats.bytes += skb->len; |
| htb_activate(q, cl); |
| } |
| |
| sch->q.qlen++; |
| sch->bstats.packets += skb_is_gso(skb)?skb_shinfo(skb)->gso_segs:1; |
| sch->bstats.bytes += skb->len; |
| return NET_XMIT_SUCCESS; |
| } |
| |
| /* TODO: requeuing packet charges it to policers again !! */ |
| static int htb_requeue(struct sk_buff *skb, struct Qdisc *sch) |
| { |
| int ret; |
| struct htb_sched *q = qdisc_priv(sch); |
| struct htb_class *cl = htb_classify(skb, sch, &ret); |
| struct sk_buff *tskb; |
| |
| if (cl == HTB_DIRECT) { |
| /* enqueue to helper queue */ |
| if (q->direct_queue.qlen < q->direct_qlen) { |
| __skb_queue_head(&q->direct_queue, skb); |
| } else { |
| __skb_queue_head(&q->direct_queue, skb); |
| tskb = __skb_dequeue_tail(&q->direct_queue); |
| kfree_skb(tskb); |
| sch->qstats.drops++; |
| return NET_XMIT_CN; |
| } |
| #ifdef CONFIG_NET_CLS_ACT |
| } else if (!cl) { |
| if (ret == NET_XMIT_BYPASS) |
| sch->qstats.drops++; |
| kfree_skb(skb); |
| return ret; |
| #endif |
| } else if (cl->un.leaf.q->ops->requeue(skb, cl->un.leaf.q) != |
| NET_XMIT_SUCCESS) { |
| sch->qstats.drops++; |
| cl->qstats.drops++; |
| return NET_XMIT_DROP; |
| } else |
| htb_activate(q, cl); |
| |
| sch->q.qlen++; |
| sch->qstats.requeues++; |
| return NET_XMIT_SUCCESS; |
| } |
| |
| /** |
| * htb_charge_class - charges amount "bytes" to leaf and ancestors |
| * |
| * Routine assumes that packet "bytes" long was dequeued from leaf cl |
| * borrowing from "level". It accounts bytes to ceil leaky bucket for |
| * leaf and all ancestors and to rate bucket for ancestors at levels |
| * "level" and higher. It also handles possible change of mode resulting |
| * from the update. Note that mode can also increase here (MAY_BORROW to |
| * CAN_SEND) because we can use more precise clock that event queue here. |
| * In such case we remove class from event queue first. |
| */ |
| static void htb_charge_class(struct htb_sched *q, struct htb_class *cl, |
| int level, struct sk_buff *skb) |
| { |
| int bytes = skb->len; |
| long toks, diff; |
| enum htb_cmode old_mode; |
| |
| #define HTB_ACCNT(T,B,R) toks = diff + cl->T; \ |
| if (toks > cl->B) toks = cl->B; \ |
| toks -= L2T(cl, cl->R, bytes); \ |
| if (toks <= -cl->mbuffer) toks = 1-cl->mbuffer; \ |
| cl->T = toks |
| |
| while (cl) { |
| diff = psched_tdiff_bounded(q->now, cl->t_c, cl->mbuffer); |
| if (cl->level >= level) { |
| if (cl->level == level) |
| cl->xstats.lends++; |
| HTB_ACCNT(tokens, buffer, rate); |
| } else { |
| cl->xstats.borrows++; |
| cl->tokens += diff; /* we moved t_c; update tokens */ |
| } |
| HTB_ACCNT(ctokens, cbuffer, ceil); |
| cl->t_c = q->now; |
| |
| old_mode = cl->cmode; |
| diff = 0; |
| htb_change_class_mode(q, cl, &diff); |
| if (old_mode != cl->cmode) { |
| if (old_mode != HTB_CAN_SEND) |
| htb_safe_rb_erase(&cl->pq_node, q->wait_pq + cl->level); |
| if (cl->cmode != HTB_CAN_SEND) |
| htb_add_to_wait_tree(q, cl, diff); |
| } |
| |
| /* update byte stats except for leaves which are already updated */ |
| if (cl->level) { |
| cl->bstats.bytes += bytes; |
| cl->bstats.packets += skb_is_gso(skb)? |
| skb_shinfo(skb)->gso_segs:1; |
| } |
| cl = cl->parent; |
| } |
| } |
| |
| /** |
| * htb_do_events - make mode changes to classes at the level |
| * |
| * Scans event queue for pending events and applies them. Returns time of |
| * next pending event (0 for no event in pq). |
| * Note: Applied are events whose have cl->pq_key <= q->now. |
| */ |
| static psched_time_t htb_do_events(struct htb_sched *q, int level) |
| { |
| /* don't run for longer than 2 jiffies; 2 is used instead of |
| 1 to simplify things when jiffy is going to be incremented |
| too soon */ |
| unsigned long stop_at = jiffies + 2; |
| while (time_before(jiffies, stop_at)) { |
| struct htb_class *cl; |
| long diff; |
| struct rb_node *p = rb_first(&q->wait_pq[level]); |
| |
| if (!p) |
| return 0; |
| |
| cl = rb_entry(p, struct htb_class, pq_node); |
| if (cl->pq_key > q->now) |
| return cl->pq_key; |
| |
| htb_safe_rb_erase(p, q->wait_pq + level); |
| diff = psched_tdiff_bounded(q->now, cl->t_c, cl->mbuffer); |
| htb_change_class_mode(q, cl, &diff); |
| if (cl->cmode != HTB_CAN_SEND) |
| htb_add_to_wait_tree(q, cl, diff); |
| } |
| /* too much load - let's continue on next jiffie */ |
| return q->now + PSCHED_TICKS_PER_SEC / HZ; |
| } |
| |
| /* Returns class->node+prio from id-tree where classe's id is >= id. NULL |
| is no such one exists. */ |
| static struct rb_node *htb_id_find_next_upper(int prio, struct rb_node *n, |
| u32 id) |
| { |
| struct rb_node *r = NULL; |
| while (n) { |
| struct htb_class *cl = |
| rb_entry(n, struct htb_class, node[prio]); |
| if (id == cl->classid) |
| return n; |
| |
| if (id > cl->classid) { |
| n = n->rb_right; |
| } else { |
| r = n; |
| n = n->rb_left; |
| } |
| } |
| return r; |
| } |
| |
| /** |
| * htb_lookup_leaf - returns next leaf class in DRR order |
| * |
| * Find leaf where current feed pointers points to. |
| */ |
| static struct htb_class *htb_lookup_leaf(struct rb_root *tree, int prio, |
| struct rb_node **pptr, u32 * pid) |
| { |
| int i; |
| struct { |
| struct rb_node *root; |
| struct rb_node **pptr; |
| u32 *pid; |
| } stk[TC_HTB_MAXDEPTH], *sp = stk; |
| |
| BUG_TRAP(tree->rb_node); |
| sp->root = tree->rb_node; |
| sp->pptr = pptr; |
| sp->pid = pid; |
| |
| for (i = 0; i < 65535; i++) { |
| if (!*sp->pptr && *sp->pid) { |
| /* ptr was invalidated but id is valid - try to recover |
| the original or next ptr */ |
| *sp->pptr = |
| htb_id_find_next_upper(prio, sp->root, *sp->pid); |
| } |
| *sp->pid = 0; /* ptr is valid now so that remove this hint as it |
| can become out of date quickly */ |
| if (!*sp->pptr) { /* we are at right end; rewind & go up */ |
| *sp->pptr = sp->root; |
| while ((*sp->pptr)->rb_left) |
| *sp->pptr = (*sp->pptr)->rb_left; |
| if (sp > stk) { |
| sp--; |
| BUG_TRAP(*sp->pptr); |
| if (!*sp->pptr) |
| return NULL; |
| htb_next_rb_node(sp->pptr); |
| } |
| } else { |
| struct htb_class *cl; |
| cl = rb_entry(*sp->pptr, struct htb_class, node[prio]); |
| if (!cl->level) |
| return cl; |
| (++sp)->root = cl->un.inner.feed[prio].rb_node; |
| sp->pptr = cl->un.inner.ptr + prio; |
| sp->pid = cl->un.inner.last_ptr_id + prio; |
| } |
| } |
| BUG_TRAP(0); |
| return NULL; |
| } |
| |
| /* dequeues packet at given priority and level; call only if |
| you are sure that there is active class at prio/level */ |
| static struct sk_buff *htb_dequeue_tree(struct htb_sched *q, int prio, |
| int level) |
| { |
| struct sk_buff *skb = NULL; |
| struct htb_class *cl, *start; |
| /* look initial class up in the row */ |
| start = cl = htb_lookup_leaf(q->row[level] + prio, prio, |
| q->ptr[level] + prio, |
| q->last_ptr_id[level] + prio); |
| |
| do { |
| next: |
| BUG_TRAP(cl); |
| if (!cl) |
| return NULL; |
| |
| /* class can be empty - it is unlikely but can be true if leaf |
| qdisc drops packets in enqueue routine or if someone used |
| graft operation on the leaf since last dequeue; |
| simply deactivate and skip such class */ |
| if (unlikely(cl->un.leaf.q->q.qlen == 0)) { |
| struct htb_class *next; |
| htb_deactivate(q, cl); |
| |
| /* row/level might become empty */ |
| if ((q->row_mask[level] & (1 << prio)) == 0) |
| return NULL; |
| |
| next = htb_lookup_leaf(q->row[level] + prio, |
| prio, q->ptr[level] + prio, |
| q->last_ptr_id[level] + prio); |
| |
| if (cl == start) /* fix start if we just deleted it */ |
| start = next; |
| cl = next; |
| goto next; |
| } |
| |
| skb = cl->un.leaf.q->dequeue(cl->un.leaf.q); |
| if (likely(skb != NULL)) |
| break; |
| if (!cl->warned) { |
| printk(KERN_WARNING |
| "htb: class %X isn't work conserving ?!\n", |
| cl->classid); |
| cl->warned = 1; |
| } |
| q->nwc_hit++; |
| htb_next_rb_node((level ? cl->parent->un.inner.ptr : q-> |
| ptr[0]) + prio); |
| cl = htb_lookup_leaf(q->row[level] + prio, prio, |
| q->ptr[level] + prio, |
| q->last_ptr_id[level] + prio); |
| |
| } while (cl != start); |
| |
| if (likely(skb != NULL)) { |
| if ((cl->un.leaf.deficit[level] -= skb->len) < 0) { |
| cl->un.leaf.deficit[level] += cl->un.leaf.quantum; |
| htb_next_rb_node((level ? cl->parent->un.inner.ptr : q-> |
| ptr[0]) + prio); |
| } |
| /* this used to be after charge_class but this constelation |
| gives us slightly better performance */ |
| if (!cl->un.leaf.q->q.qlen) |
| htb_deactivate(q, cl); |
| htb_charge_class(q, cl, level, skb); |
| } |
| return skb; |
| } |
| |
| static struct sk_buff *htb_dequeue(struct Qdisc *sch) |
| { |
| struct sk_buff *skb = NULL; |
| struct htb_sched *q = qdisc_priv(sch); |
| int level; |
| psched_time_t next_event; |
| |
| /* try to dequeue direct packets as high prio (!) to minimize cpu work */ |
| skb = __skb_dequeue(&q->direct_queue); |
| if (skb != NULL) { |
| sch->flags &= ~TCQ_F_THROTTLED; |
| sch->q.qlen--; |
| return skb; |
| } |
| |
| if (!sch->q.qlen) |
| goto fin; |
| q->now = psched_get_time(); |
| |
| next_event = q->now + 5 * PSCHED_TICKS_PER_SEC; |
| q->nwc_hit = 0; |
| for (level = 0; level < TC_HTB_MAXDEPTH; level++) { |
| /* common case optimization - skip event handler quickly */ |
| int m; |
| psched_time_t event; |
| |
| if (q->now >= q->near_ev_cache[level]) { |
| event = htb_do_events(q, level); |
| if (!event) |
| event = q->now + PSCHED_TICKS_PER_SEC; |
| q->near_ev_cache[level] = event; |
| } else |
| event = q->near_ev_cache[level]; |
| |
| if (event && next_event > event) |
| next_event = event; |
| |
| m = ~q->row_mask[level]; |
| while (m != (int)(-1)) { |
| int prio = ffz(m); |
| m |= 1 << prio; |
| skb = htb_dequeue_tree(q, prio, level); |
| if (likely(skb != NULL)) { |
| sch->q.qlen--; |
| sch->flags &= ~TCQ_F_THROTTLED; |
| goto fin; |
| } |
| } |
| } |
| sch->qstats.overlimits++; |
| qdisc_watchdog_schedule(&q->watchdog, next_event); |
| fin: |
| return skb; |
| } |
| |
| /* try to drop from each class (by prio) until one succeed */ |
| static unsigned int htb_drop(struct Qdisc *sch) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| int prio; |
| |
| for (prio = TC_HTB_NUMPRIO - 1; prio >= 0; prio--) { |
| struct list_head *p; |
| list_for_each(p, q->drops + prio) { |
| struct htb_class *cl = list_entry(p, struct htb_class, |
| un.leaf.drop_list); |
| unsigned int len; |
| if (cl->un.leaf.q->ops->drop && |
| (len = cl->un.leaf.q->ops->drop(cl->un.leaf.q))) { |
| sch->q.qlen--; |
| if (!cl->un.leaf.q->q.qlen) |
| htb_deactivate(q, cl); |
| return len; |
| } |
| } |
| } |
| return 0; |
| } |
| |
| /* reset all classes */ |
| /* always caled under BH & queue lock */ |
| static void htb_reset(struct Qdisc *sch) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| int i; |
| |
| for (i = 0; i < HTB_HSIZE; i++) { |
| struct hlist_node *p; |
| struct htb_class *cl; |
| |
| hlist_for_each_entry(cl, p, q->hash + i, hlist) { |
| if (cl->level) |
| memset(&cl->un.inner, 0, sizeof(cl->un.inner)); |
| else { |
| if (cl->un.leaf.q) |
| qdisc_reset(cl->un.leaf.q); |
| INIT_LIST_HEAD(&cl->un.leaf.drop_list); |
| } |
| cl->prio_activity = 0; |
| cl->cmode = HTB_CAN_SEND; |
| |
| } |
| } |
| qdisc_watchdog_cancel(&q->watchdog); |
| __skb_queue_purge(&q->direct_queue); |
| sch->q.qlen = 0; |
| memset(q->row, 0, sizeof(q->row)); |
| memset(q->row_mask, 0, sizeof(q->row_mask)); |
| memset(q->wait_pq, 0, sizeof(q->wait_pq)); |
| memset(q->ptr, 0, sizeof(q->ptr)); |
| for (i = 0; i < TC_HTB_NUMPRIO; i++) |
| INIT_LIST_HEAD(q->drops + i); |
| } |
| |
| static const struct nla_policy htb_policy[TCA_HTB_MAX + 1] = { |
| [TCA_HTB_PARMS] = { .len = sizeof(struct tc_htb_opt) }, |
| [TCA_HTB_INIT] = { .len = sizeof(struct tc_htb_glob) }, |
| [TCA_HTB_CTAB] = { .type = NLA_BINARY, .len = TC_RTAB_SIZE }, |
| [TCA_HTB_RTAB] = { .type = NLA_BINARY, .len = TC_RTAB_SIZE }, |
| }; |
| |
| static int htb_init(struct Qdisc *sch, struct nlattr *opt) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| struct nlattr *tb[TCA_HTB_INIT + 1]; |
| struct tc_htb_glob *gopt; |
| int err; |
| int i; |
| |
| if (!opt) |
| return -EINVAL; |
| |
| err = nla_parse_nested(tb, TCA_HTB_INIT, opt, htb_policy); |
| if (err < 0) |
| return err; |
| |
| if (tb[TCA_HTB_INIT] == NULL) { |
| printk(KERN_ERR "HTB: hey probably you have bad tc tool ?\n"); |
| return -EINVAL; |
| } |
| gopt = nla_data(tb[TCA_HTB_INIT]); |
| if (gopt->version != HTB_VER >> 16) { |
| printk(KERN_ERR |
| "HTB: need tc/htb version %d (minor is %d), you have %d\n", |
| HTB_VER >> 16, HTB_VER & 0xffff, gopt->version); |
| return -EINVAL; |
| } |
| |
| INIT_LIST_HEAD(&q->root); |
| for (i = 0; i < HTB_HSIZE; i++) |
| INIT_HLIST_HEAD(q->hash + i); |
| for (i = 0; i < TC_HTB_NUMPRIO; i++) |
| INIT_LIST_HEAD(q->drops + i); |
| |
| qdisc_watchdog_init(&q->watchdog, sch); |
| skb_queue_head_init(&q->direct_queue); |
| |
| q->direct_qlen = sch->dev->tx_queue_len; |
| if (q->direct_qlen < 2) /* some devices have zero tx_queue_len */ |
| q->direct_qlen = 2; |
| |
| if ((q->rate2quantum = gopt->rate2quantum) < 1) |
| q->rate2quantum = 1; |
| q->defcls = gopt->defcls; |
| |
| return 0; |
| } |
| |
| static int htb_dump(struct Qdisc *sch, struct sk_buff *skb) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| struct nlattr *nest; |
| struct tc_htb_glob gopt; |
| |
| spin_lock_bh(&sch->dev->queue_lock); |
| |
| gopt.direct_pkts = q->direct_pkts; |
| gopt.version = HTB_VER; |
| gopt.rate2quantum = q->rate2quantum; |
| gopt.defcls = q->defcls; |
| gopt.debug = 0; |
| |
| nest = nla_nest_start(skb, TCA_OPTIONS); |
| if (nest == NULL) |
| goto nla_put_failure; |
| NLA_PUT(skb, TCA_HTB_INIT, sizeof(gopt), &gopt); |
| nla_nest_end(skb, nest); |
| |
| spin_unlock_bh(&sch->dev->queue_lock); |
| return skb->len; |
| |
| nla_put_failure: |
| spin_unlock_bh(&sch->dev->queue_lock); |
| nla_nest_cancel(skb, nest); |
| return -1; |
| } |
| |
| static int htb_dump_class(struct Qdisc *sch, unsigned long arg, |
| struct sk_buff *skb, struct tcmsg *tcm) |
| { |
| struct htb_class *cl = (struct htb_class *)arg; |
| struct nlattr *nest; |
| struct tc_htb_opt opt; |
| |
| spin_lock_bh(&sch->dev->queue_lock); |
| tcm->tcm_parent = cl->parent ? cl->parent->classid : TC_H_ROOT; |
| tcm->tcm_handle = cl->classid; |
| if (!cl->level && cl->un.leaf.q) |
| tcm->tcm_info = cl->un.leaf.q->handle; |
| |
| nest = nla_nest_start(skb, TCA_OPTIONS); |
| if (nest == NULL) |
| goto nla_put_failure; |
| |
| memset(&opt, 0, sizeof(opt)); |
| |
| opt.rate = cl->rate->rate; |
| opt.buffer = cl->buffer; |
| opt.ceil = cl->ceil->rate; |
| opt.cbuffer = cl->cbuffer; |
| opt.quantum = cl->un.leaf.quantum; |
| opt.prio = cl->un.leaf.prio; |
| opt.level = cl->level; |
| NLA_PUT(skb, TCA_HTB_PARMS, sizeof(opt), &opt); |
| |
| nla_nest_end(skb, nest); |
| spin_unlock_bh(&sch->dev->queue_lock); |
| return skb->len; |
| |
| nla_put_failure: |
| spin_unlock_bh(&sch->dev->queue_lock); |
| nla_nest_cancel(skb, nest); |
| return -1; |
| } |
| |
| static int |
| htb_dump_class_stats(struct Qdisc *sch, unsigned long arg, struct gnet_dump *d) |
| { |
| struct htb_class *cl = (struct htb_class *)arg; |
| |
| if (!cl->level && cl->un.leaf.q) |
| cl->qstats.qlen = cl->un.leaf.q->q.qlen; |
| cl->xstats.tokens = cl->tokens; |
| cl->xstats.ctokens = cl->ctokens; |
| |
| if (gnet_stats_copy_basic(d, &cl->bstats) < 0 || |
| gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 || |
| gnet_stats_copy_queue(d, &cl->qstats) < 0) |
| return -1; |
| |
| return gnet_stats_copy_app(d, &cl->xstats, sizeof(cl->xstats)); |
| } |
| |
| static int htb_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new, |
| struct Qdisc **old) |
| { |
| struct htb_class *cl = (struct htb_class *)arg; |
| |
| if (cl && !cl->level) { |
| if (new == NULL && |
| (new = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops, |
| cl->classid)) |
| == NULL) |
| return -ENOBUFS; |
| sch_tree_lock(sch); |
| if ((*old = xchg(&cl->un.leaf.q, new)) != NULL) { |
| qdisc_tree_decrease_qlen(*old, (*old)->q.qlen); |
| qdisc_reset(*old); |
| } |
| sch_tree_unlock(sch); |
| return 0; |
| } |
| return -ENOENT; |
| } |
| |
| static struct Qdisc *htb_leaf(struct Qdisc *sch, unsigned long arg) |
| { |
| struct htb_class *cl = (struct htb_class *)arg; |
| return (cl && !cl->level) ? cl->un.leaf.q : NULL; |
| } |
| |
| static void htb_qlen_notify(struct Qdisc *sch, unsigned long arg) |
| { |
| struct htb_class *cl = (struct htb_class *)arg; |
| |
| if (cl->un.leaf.q->q.qlen == 0) |
| htb_deactivate(qdisc_priv(sch), cl); |
| } |
| |
| static unsigned long htb_get(struct Qdisc *sch, u32 classid) |
| { |
| struct htb_class *cl = htb_find(classid, sch); |
| if (cl) |
| cl->refcnt++; |
| return (unsigned long)cl; |
| } |
| |
| static inline int htb_parent_last_child(struct htb_class *cl) |
| { |
| if (!cl->parent) |
| /* the root class */ |
| return 0; |
| |
| if (!(cl->parent->children.next == &cl->sibling && |
| cl->parent->children.prev == &cl->sibling)) |
| /* not the last child */ |
| return 0; |
| |
| return 1; |
| } |
| |
| static void htb_parent_to_leaf(struct htb_sched *q, struct htb_class *cl, |
| struct Qdisc *new_q) |
| { |
| struct htb_class *parent = cl->parent; |
| |
| BUG_TRAP(!cl->level && cl->un.leaf.q && !cl->prio_activity); |
| |
| if (parent->cmode != HTB_CAN_SEND) |
| htb_safe_rb_erase(&parent->pq_node, q->wait_pq + parent->level); |
| |
| parent->level = 0; |
| memset(&parent->un.inner, 0, sizeof(parent->un.inner)); |
| INIT_LIST_HEAD(&parent->un.leaf.drop_list); |
| parent->un.leaf.q = new_q ? new_q : &noop_qdisc; |
| parent->un.leaf.quantum = parent->quantum; |
| parent->un.leaf.prio = parent->prio; |
| parent->tokens = parent->buffer; |
| parent->ctokens = parent->cbuffer; |
| parent->t_c = psched_get_time(); |
| parent->cmode = HTB_CAN_SEND; |
| } |
| |
| static void htb_destroy_class(struct Qdisc *sch, struct htb_class *cl) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| |
| if (!cl->level) { |
| BUG_TRAP(cl->un.leaf.q); |
| qdisc_destroy(cl->un.leaf.q); |
| } |
| gen_kill_estimator(&cl->bstats, &cl->rate_est); |
| qdisc_put_rtab(cl->rate); |
| qdisc_put_rtab(cl->ceil); |
| |
| tcf_destroy_chain(&cl->filter_list); |
| |
| while (!list_empty(&cl->children)) |
| htb_destroy_class(sch, list_entry(cl->children.next, |
| struct htb_class, sibling)); |
| |
| /* note: this delete may happen twice (see htb_delete) */ |
| hlist_del_init(&cl->hlist); |
| list_del(&cl->sibling); |
| |
| if (cl->prio_activity) |
| htb_deactivate(q, cl); |
| |
| if (cl->cmode != HTB_CAN_SEND) |
| htb_safe_rb_erase(&cl->pq_node, q->wait_pq + cl->level); |
| |
| kfree(cl); |
| } |
| |
| /* always caled under BH & queue lock */ |
| static void htb_destroy(struct Qdisc *sch) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| |
| qdisc_watchdog_cancel(&q->watchdog); |
| /* This line used to be after htb_destroy_class call below |
| and surprisingly it worked in 2.4. But it must precede it |
| because filter need its target class alive to be able to call |
| unbind_filter on it (without Oops). */ |
| tcf_destroy_chain(&q->filter_list); |
| |
| while (!list_empty(&q->root)) |
| htb_destroy_class(sch, list_entry(q->root.next, |
| struct htb_class, sibling)); |
| |
| __skb_queue_purge(&q->direct_queue); |
| } |
| |
| static int htb_delete(struct Qdisc *sch, unsigned long arg) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| struct htb_class *cl = (struct htb_class *)arg; |
| unsigned int qlen; |
| struct Qdisc *new_q = NULL; |
| int last_child = 0; |
| |
| // TODO: why don't allow to delete subtree ? references ? does |
| // tc subsys quarantee us that in htb_destroy it holds no class |
| // refs so that we can remove children safely there ? |
| if (!list_empty(&cl->children) || cl->filter_cnt) |
| return -EBUSY; |
| |
| if (!cl->level && htb_parent_last_child(cl)) { |
| new_q = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops, |
| cl->parent->classid); |
| last_child = 1; |
| } |
| |
| sch_tree_lock(sch); |
| |
| if (!cl->level) { |
| qlen = cl->un.leaf.q->q.qlen; |
| qdisc_reset(cl->un.leaf.q); |
| qdisc_tree_decrease_qlen(cl->un.leaf.q, qlen); |
| } |
| |
| /* delete from hash and active; remainder in destroy_class */ |
| hlist_del_init(&cl->hlist); |
| |
| if (cl->prio_activity) |
| htb_deactivate(q, cl); |
| |
| if (last_child) |
| htb_parent_to_leaf(q, cl, new_q); |
| |
| if (--cl->refcnt == 0) |
| htb_destroy_class(sch, cl); |
| |
| sch_tree_unlock(sch); |
| return 0; |
| } |
| |
| static void htb_put(struct Qdisc *sch, unsigned long arg) |
| { |
| struct htb_class *cl = (struct htb_class *)arg; |
| |
| if (--cl->refcnt == 0) |
| htb_destroy_class(sch, cl); |
| } |
| |
| static int htb_change_class(struct Qdisc *sch, u32 classid, |
| u32 parentid, struct nlattr **tca, |
| unsigned long *arg) |
| { |
| int err = -EINVAL; |
| struct htb_sched *q = qdisc_priv(sch); |
| struct htb_class *cl = (struct htb_class *)*arg, *parent; |
| struct nlattr *opt = tca[TCA_OPTIONS]; |
| struct qdisc_rate_table *rtab = NULL, *ctab = NULL; |
| struct nlattr *tb[TCA_HTB_RTAB + 1]; |
| struct tc_htb_opt *hopt; |
| |
| /* extract all subattrs from opt attr */ |
| if (!opt) |
| goto failure; |
| |
| err = nla_parse_nested(tb, TCA_HTB_RTAB, opt, htb_policy); |
| if (err < 0) |
| goto failure; |
| |
| err = -EINVAL; |
| if (tb[TCA_HTB_PARMS] == NULL) |
| goto failure; |
| |
| parent = parentid == TC_H_ROOT ? NULL : htb_find(parentid, sch); |
| |
| hopt = nla_data(tb[TCA_HTB_PARMS]); |
| |
| rtab = qdisc_get_rtab(&hopt->rate, tb[TCA_HTB_RTAB]); |
| ctab = qdisc_get_rtab(&hopt->ceil, tb[TCA_HTB_CTAB]); |
| if (!rtab || !ctab) |
| goto failure; |
| |
| if (!cl) { /* new class */ |
| struct Qdisc *new_q; |
| int prio; |
| struct { |
| struct nlattr nla; |
| struct gnet_estimator opt; |
| } est = { |
| .nla = { |
| .nla_len = nla_attr_size(sizeof(est.opt)), |
| .nla_type = TCA_RATE, |
| }, |
| .opt = { |
| /* 4s interval, 16s averaging constant */ |
| .interval = 2, |
| .ewma_log = 2, |
| }, |
| }; |
| |
| /* check for valid classid */ |
| if (!classid || TC_H_MAJ(classid ^ sch->handle) |
| || htb_find(classid, sch)) |
| goto failure; |
| |
| /* check maximal depth */ |
| if (parent && parent->parent && parent->parent->level < 2) { |
| printk(KERN_ERR "htb: tree is too deep\n"); |
| goto failure; |
| } |
| err = -ENOBUFS; |
| if ((cl = kzalloc(sizeof(*cl), GFP_KERNEL)) == NULL) |
| goto failure; |
| |
| gen_new_estimator(&cl->bstats, &cl->rate_est, |
| &sch->dev->queue_lock, |
| tca[TCA_RATE] ? : &est.nla); |
| cl->refcnt = 1; |
| INIT_LIST_HEAD(&cl->sibling); |
| INIT_HLIST_NODE(&cl->hlist); |
| INIT_LIST_HEAD(&cl->children); |
| INIT_LIST_HEAD(&cl->un.leaf.drop_list); |
| RB_CLEAR_NODE(&cl->pq_node); |
| |
| for (prio = 0; prio < TC_HTB_NUMPRIO; prio++) |
| RB_CLEAR_NODE(&cl->node[prio]); |
| |
| /* create leaf qdisc early because it uses kmalloc(GFP_KERNEL) |
| so that can't be used inside of sch_tree_lock |
| -- thanks to Karlis Peisenieks */ |
| new_q = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops, classid); |
| sch_tree_lock(sch); |
| if (parent && !parent->level) { |
| unsigned int qlen = parent->un.leaf.q->q.qlen; |
| |
| /* turn parent into inner node */ |
| qdisc_reset(parent->un.leaf.q); |
| qdisc_tree_decrease_qlen(parent->un.leaf.q, qlen); |
| qdisc_destroy(parent->un.leaf.q); |
| if (parent->prio_activity) |
| htb_deactivate(q, parent); |
| |
| /* remove from evt list because of level change */ |
| if (parent->cmode != HTB_CAN_SEND) { |
| htb_safe_rb_erase(&parent->pq_node, q->wait_pq); |
| parent->cmode = HTB_CAN_SEND; |
| } |
| parent->level = (parent->parent ? parent->parent->level |
| : TC_HTB_MAXDEPTH) - 1; |
| memset(&parent->un.inner, 0, sizeof(parent->un.inner)); |
| } |
| /* leaf (we) needs elementary qdisc */ |
| cl->un.leaf.q = new_q ? new_q : &noop_qdisc; |
| |
| cl->classid = classid; |
| cl->parent = parent; |
| |
| /* set class to be in HTB_CAN_SEND state */ |
| cl->tokens = hopt->buffer; |
| cl->ctokens = hopt->cbuffer; |
| cl->mbuffer = 60 * PSCHED_TICKS_PER_SEC; /* 1min */ |
| cl->t_c = psched_get_time(); |
| cl->cmode = HTB_CAN_SEND; |
| |
| /* attach to the hash list and parent's family */ |
| hlist_add_head(&cl->hlist, q->hash + htb_hash(classid)); |
| list_add_tail(&cl->sibling, |
| parent ? &parent->children : &q->root); |
| } else { |
| if (tca[TCA_RATE]) |
| gen_replace_estimator(&cl->bstats, &cl->rate_est, |
| &sch->dev->queue_lock, |
| tca[TCA_RATE]); |
| sch_tree_lock(sch); |
| } |
| |
| /* it used to be a nasty bug here, we have to check that node |
| is really leaf before changing cl->un.leaf ! */ |
| if (!cl->level) { |
| cl->un.leaf.quantum = rtab->rate.rate / q->rate2quantum; |
| if (!hopt->quantum && cl->un.leaf.quantum < 1000) { |
| printk(KERN_WARNING |
| "HTB: quantum of class %X is small. Consider r2q change.\n", |
| cl->classid); |
| cl->un.leaf.quantum = 1000; |
| } |
| if (!hopt->quantum && cl->un.leaf.quantum > 200000) { |
| printk(KERN_WARNING |
| "HTB: quantum of class %X is big. Consider r2q change.\n", |
| cl->classid); |
| cl->un.leaf.quantum = 200000; |
| } |
| if (hopt->quantum) |
| cl->un.leaf.quantum = hopt->quantum; |
| if ((cl->un.leaf.prio = hopt->prio) >= TC_HTB_NUMPRIO) |
| cl->un.leaf.prio = TC_HTB_NUMPRIO - 1; |
| |
| /* backup for htb_parent_to_leaf */ |
| cl->quantum = cl->un.leaf.quantum; |
| cl->prio = cl->un.leaf.prio; |
| } |
| |
| cl->buffer = hopt->buffer; |
| cl->cbuffer = hopt->cbuffer; |
| if (cl->rate) |
| qdisc_put_rtab(cl->rate); |
| cl->rate = rtab; |
| if (cl->ceil) |
| qdisc_put_rtab(cl->ceil); |
| cl->ceil = ctab; |
| sch_tree_unlock(sch); |
| |
| *arg = (unsigned long)cl; |
| return 0; |
| |
| failure: |
| if (rtab) |
| qdisc_put_rtab(rtab); |
| if (ctab) |
| qdisc_put_rtab(ctab); |
| return err; |
| } |
| |
| static struct tcf_proto **htb_find_tcf(struct Qdisc *sch, unsigned long arg) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| struct htb_class *cl = (struct htb_class *)arg; |
| struct tcf_proto **fl = cl ? &cl->filter_list : &q->filter_list; |
| |
| return fl; |
| } |
| |
| static unsigned long htb_bind_filter(struct Qdisc *sch, unsigned long parent, |
| u32 classid) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| struct htb_class *cl = htb_find(classid, sch); |
| |
| /*if (cl && !cl->level) return 0; |
| The line above used to be there to prevent attaching filters to |
| leaves. But at least tc_index filter uses this just to get class |
| for other reasons so that we have to allow for it. |
| ---- |
| 19.6.2002 As Werner explained it is ok - bind filter is just |
| another way to "lock" the class - unlike "get" this lock can |
| be broken by class during destroy IIUC. |
| */ |
| if (cl) |
| cl->filter_cnt++; |
| else |
| q->filter_cnt++; |
| return (unsigned long)cl; |
| } |
| |
| static void htb_unbind_filter(struct Qdisc *sch, unsigned long arg) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| struct htb_class *cl = (struct htb_class *)arg; |
| |
| if (cl) |
| cl->filter_cnt--; |
| else |
| q->filter_cnt--; |
| } |
| |
| static void htb_walk(struct Qdisc *sch, struct qdisc_walker *arg) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| int i; |
| |
| if (arg->stop) |
| return; |
| |
| for (i = 0; i < HTB_HSIZE; i++) { |
| struct hlist_node *p; |
| struct htb_class *cl; |
| |
| hlist_for_each_entry(cl, p, q->hash + i, hlist) { |
| if (arg->count < arg->skip) { |
| arg->count++; |
| continue; |
| } |
| if (arg->fn(sch, (unsigned long)cl, arg) < 0) { |
| arg->stop = 1; |
| return; |
| } |
| arg->count++; |
| } |
| } |
| } |
| |
| static const struct Qdisc_class_ops htb_class_ops = { |
| .graft = htb_graft, |
| .leaf = htb_leaf, |
| .qlen_notify = htb_qlen_notify, |
| .get = htb_get, |
| .put = htb_put, |
| .change = htb_change_class, |
| .delete = htb_delete, |
| .walk = htb_walk, |
| .tcf_chain = htb_find_tcf, |
| .bind_tcf = htb_bind_filter, |
| .unbind_tcf = htb_unbind_filter, |
| .dump = htb_dump_class, |
| .dump_stats = htb_dump_class_stats, |
| }; |
| |
| static struct Qdisc_ops htb_qdisc_ops __read_mostly = { |
| .next = NULL, |
| .cl_ops = &htb_class_ops, |
| .id = "htb", |
| .priv_size = sizeof(struct htb_sched), |
| .enqueue = htb_enqueue, |
| .dequeue = htb_dequeue, |
| .requeue = htb_requeue, |
| .drop = htb_drop, |
| .init = htb_init, |
| .reset = htb_reset, |
| .destroy = htb_destroy, |
| .change = NULL /* htb_change */, |
| .dump = htb_dump, |
| .owner = THIS_MODULE, |
| }; |
| |
| static int __init htb_module_init(void) |
| { |
| return register_qdisc(&htb_qdisc_ops); |
| } |
| static void __exit htb_module_exit(void) |
| { |
| unregister_qdisc(&htb_qdisc_ops); |
| } |
| |
| module_init(htb_module_init) |
| module_exit(htb_module_exit) |
| MODULE_LICENSE("GPL"); |