| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * net/sched/sch_htb.c Hierarchical token bucket, feed tree 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. |
| */ |
| #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 <linux/workqueue.h> |
| #include <linux/slab.h> |
| #include <net/netlink.h> |
| #include <net/sch_generic.h> |
| #include <net/pkt_sched.h> |
| #include <net/pkt_cls.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. |
| */ |
| |
| 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"); |
| |
| static int htb_rate_est = 0; /* htb classes have a default rate estimator */ |
| module_param(htb_rate_est, int, 0640); |
| MODULE_PARM_DESC(htb_rate_est, "setup a default rate estimator (4sec 16sec) for htb classes"); |
| |
| /* 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 */ |
| }; |
| |
| struct htb_prio { |
| union { |
| struct rb_root row; |
| struct rb_root feed; |
| }; |
| struct rb_node *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; |
| }; |
| |
| /* interior & leaf nodes; props specific to leaves are marked L: |
| * To reduce false sharing, place mostly read fields at beginning, |
| * and mostly written ones at the end. |
| */ |
| struct htb_class { |
| struct Qdisc_class_common common; |
| struct psched_ratecfg rate; |
| struct psched_ratecfg ceil; |
| s64 buffer, cbuffer;/* token bucket depth/rate */ |
| s64 mbuffer; /* max wait time */ |
| u32 prio; /* these two are used only by leaves... */ |
| int quantum; /* but stored for parent-to-leaf return */ |
| |
| struct tcf_proto __rcu *filter_list; /* class attached filters */ |
| struct tcf_block *block; |
| int filter_cnt; |
| |
| int level; /* our level (see above) */ |
| unsigned int children; |
| struct htb_class *parent; /* parent class */ |
| |
| struct net_rate_estimator __rcu *rate_est; |
| |
| /* |
| * Written often fields |
| */ |
| struct gnet_stats_basic_packed bstats; |
| struct gnet_stats_basic_packed bstats_bias; |
| struct tc_htb_xstats xstats; /* our special stats */ |
| |
| /* token bucket parameters */ |
| s64 tokens, ctokens;/* current number of tokens */ |
| s64 t_c; /* checkpoint time */ |
| |
| union { |
| struct htb_class_leaf { |
| int deficit[TC_HTB_MAXDEPTH]; |
| struct Qdisc *q; |
| } leaf; |
| struct htb_class_inner { |
| struct htb_prio clprio[TC_HTB_NUMPRIO]; |
| } inner; |
| }; |
| s64 pq_key; |
| |
| int prio_activity; /* for which prios are we active */ |
| enum htb_cmode cmode; /* current mode of the class */ |
| struct rb_node pq_node; /* node for event queue */ |
| struct rb_node node[TC_HTB_NUMPRIO]; /* node for self or feed tree */ |
| |
| unsigned int drops ____cacheline_aligned_in_smp; |
| unsigned int overlimits; |
| }; |
| |
| struct htb_level { |
| struct rb_root wait_pq; |
| struct htb_prio hprio[TC_HTB_NUMPRIO]; |
| }; |
| |
| struct htb_sched { |
| struct Qdisc_class_hash clhash; |
| int defcls; /* class where unclassified flows go to */ |
| int rate2quantum; /* quant = rate / rate2quantum */ |
| |
| /* filters for qdisc itself */ |
| struct tcf_proto __rcu *filter_list; |
| struct tcf_block *block; |
| |
| #define HTB_WARN_TOOMANYEVENTS 0x1 |
| unsigned int warned; /* only one warning */ |
| int direct_qlen; |
| struct work_struct work; |
| |
| /* non shaped skbs; let them go directly thru */ |
| struct qdisc_skb_head direct_queue; |
| u32 direct_pkts; |
| u32 overlimits; |
| |
| struct qdisc_watchdog watchdog; |
| |
| s64 now; /* cached dequeue time */ |
| |
| /* time of nearest event per level (row) */ |
| s64 near_ev_cache[TC_HTB_MAXDEPTH]; |
| |
| int row_mask[TC_HTB_MAXDEPTH]; |
| |
| struct htb_level hlevel[TC_HTB_MAXDEPTH]; |
| |
| struct Qdisc **direct_qdiscs; |
| unsigned int num_direct_qdiscs; |
| |
| bool offload; |
| }; |
| |
| /* 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 Qdisc_class_common *clc; |
| |
| clc = qdisc_class_find(&q->clhash, handle); |
| if (clc == NULL) |
| return NULL; |
| return container_of(clc, struct htb_class, common); |
| } |
| |
| static unsigned long htb_search(struct Qdisc *sch, u32 handle) |
| { |
| return (unsigned long)htb_find(handle, sch); |
| } |
| /** |
| * 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 unsuccessful |
| * then finish and return direct queue. |
| */ |
| #define HTB_DIRECT ((struct htb_class *)-1L) |
| |
| 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 */ |
| cl = htb_find(skb->priority, sch); |
| if (cl) { |
| if (cl->level == 0) |
| return cl; |
| /* Start with inner filter chain if a non-leaf class is selected */ |
| tcf = rcu_dereference_bh(cl->filter_list); |
| } else { |
| tcf = rcu_dereference_bh(q->filter_list); |
| } |
| |
| *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS; |
| while (tcf && (result = tcf_classify(skb, tcf, &res, false)) >= 0) { |
| #ifdef CONFIG_NET_CLS_ACT |
| switch (result) { |
| case TC_ACT_QUEUED: |
| case TC_ACT_STOLEN: |
| case TC_ACT_TRAP: |
| *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN; |
| fallthrough; |
| case TC_ACT_SHOT: |
| return NULL; |
| } |
| #endif |
| cl = (void *)res.class; |
| if (!cl) { |
| if (res.classid == sch->handle) |
| return HTB_DIRECT; /* X:0 (direct flow) */ |
| cl = htb_find(res.classid, sch); |
| if (!cl) |
| 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 = rcu_dereference_bh(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->common.classid > c->common.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, s64 delay) |
| { |
| struct rb_node **p = &q->hlevel[cl->level].wait_pq.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->hlevel[cl->level].wait_pq); |
| } |
| |
| /** |
| * 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->hlevel[cl->level].hprio[prio].row, 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; |
| struct htb_level *hlevel = &q->hlevel[cl->level]; |
| |
| while (mask) { |
| int prio = ffz(~mask); |
| struct htb_prio *hprio = &hlevel->hprio[prio]; |
| |
| mask &= ~(1 << prio); |
| if (hprio->ptr == cl->node + prio) |
| htb_next_rb_node(&hprio->ptr); |
| |
| htb_safe_rb_erase(cl->node + prio, &hprio->row); |
| if (!hprio->row.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->inner.clprio[prio].feed.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->inner.clprio[prio].feed, 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->inner.clprio[prio].ptr == cl->node + prio) { |
| /* we are removing child which is pointed to from |
| * parent feed - forget the pointer but remember |
| * classid |
| */ |
| p->inner.clprio[prio].last_ptr_id = cl->common.classid; |
| p->inner.clprio[prio].ptr = NULL; |
| } |
| |
| htb_safe_rb_erase(cl->node + prio, |
| &p->inner.clprio[prio].feed); |
| |
| if (!p->inner.clprio[prio].feed.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 s64 htb_lowater(const struct htb_class *cl) |
| { |
| if (htb_hysteresis) |
| return cl->cmode != HTB_CANT_SEND ? -cl->cbuffer : 0; |
| else |
| return 0; |
| } |
| static inline s64 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, s64 *diff) |
| { |
| s64 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, s64 *diff) |
| { |
| enum htb_cmode new_mode = htb_class_mode(cl, diff); |
| |
| if (new_mode == cl->cmode) |
| return; |
| |
| if (new_mode == HTB_CANT_SEND) { |
| cl->overlimits++; |
| q->overlimits++; |
| } |
| |
| 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) |
| { |
| WARN_ON(cl->level || !cl->leaf.q || !cl->leaf.q->q.qlen); |
| |
| if (!cl->prio_activity) { |
| cl->prio_activity = 1 << cl->prio; |
| htb_activate_prios(q, cl); |
| } |
| } |
| |
| /** |
| * 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) |
| { |
| WARN_ON(!cl->prio_activity); |
| |
| htb_deactivate_prios(q, cl); |
| cl->prio_activity = 0; |
| } |
| |
| static int htb_enqueue(struct sk_buff *skb, struct Qdisc *sch, |
| struct sk_buff **to_free) |
| { |
| int ret; |
| unsigned int len = qdisc_pkt_len(skb); |
| 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) { |
| __qdisc_enqueue_tail(skb, &q->direct_queue); |
| q->direct_pkts++; |
| } else { |
| return qdisc_drop(skb, sch, to_free); |
| } |
| #ifdef CONFIG_NET_CLS_ACT |
| } else if (!cl) { |
| if (ret & __NET_XMIT_BYPASS) |
| qdisc_qstats_drop(sch); |
| __qdisc_drop(skb, to_free); |
| return ret; |
| #endif |
| } else if ((ret = qdisc_enqueue(skb, cl->leaf.q, |
| to_free)) != NET_XMIT_SUCCESS) { |
| if (net_xmit_drop_count(ret)) { |
| qdisc_qstats_drop(sch); |
| cl->drops++; |
| } |
| return ret; |
| } else { |
| htb_activate(q, cl); |
| } |
| |
| sch->qstats.backlog += len; |
| sch->q.qlen++; |
| return NET_XMIT_SUCCESS; |
| } |
| |
| static inline void htb_accnt_tokens(struct htb_class *cl, int bytes, s64 diff) |
| { |
| s64 toks = diff + cl->tokens; |
| |
| if (toks > cl->buffer) |
| toks = cl->buffer; |
| toks -= (s64) psched_l2t_ns(&cl->rate, bytes); |
| if (toks <= -cl->mbuffer) |
| toks = 1 - cl->mbuffer; |
| |
| cl->tokens = toks; |
| } |
| |
| static inline void htb_accnt_ctokens(struct htb_class *cl, int bytes, s64 diff) |
| { |
| s64 toks = diff + cl->ctokens; |
| |
| if (toks > cl->cbuffer) |
| toks = cl->cbuffer; |
| toks -= (s64) psched_l2t_ns(&cl->ceil, bytes); |
| if (toks <= -cl->mbuffer) |
| toks = 1 - cl->mbuffer; |
| |
| cl->ctokens = toks; |
| } |
| |
| /** |
| * 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 = qdisc_pkt_len(skb); |
| enum htb_cmode old_mode; |
| s64 diff; |
| |
| while (cl) { |
| diff = min_t(s64, q->now - cl->t_c, cl->mbuffer); |
| if (cl->level >= level) { |
| if (cl->level == level) |
| cl->xstats.lends++; |
| htb_accnt_tokens(cl, bytes, diff); |
| } else { |
| cl->xstats.borrows++; |
| cl->tokens += diff; /* we moved t_c; update tokens */ |
| } |
| htb_accnt_ctokens(cl, bytes, diff); |
| 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->hlevel[cl->level].wait_pq); |
| if (cl->cmode != HTB_CAN_SEND) |
| htb_add_to_wait_tree(q, cl, diff); |
| } |
| |
| /* update basic stats except for leaves which are already updated */ |
| if (cl->level) |
| bstats_update(&cl->bstats, skb); |
| |
| 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, q->now for too many events). |
| * Note: Applied are events whose have cl->pq_key <= q->now. |
| */ |
| static s64 htb_do_events(struct htb_sched *q, const int level, |
| unsigned long start) |
| { |
| /* 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 = start + 2; |
| struct rb_root *wait_pq = &q->hlevel[level].wait_pq; |
| |
| while (time_before(jiffies, stop_at)) { |
| struct htb_class *cl; |
| s64 diff; |
| struct rb_node *p = rb_first(wait_pq); |
| |
| 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, wait_pq); |
| diff = min_t(s64, 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 after a break for scheduling */ |
| if (!(q->warned & HTB_WARN_TOOMANYEVENTS)) { |
| pr_warn("htb: too many events!\n"); |
| q->warned |= HTB_WARN_TOOMANYEVENTS; |
| } |
| |
| return q->now; |
| } |
| |
| /* 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->common.classid) { |
| n = n->rb_right; |
| } else if (id < cl->common.classid) { |
| r = n; |
| n = n->rb_left; |
| } else { |
| return n; |
| } |
| } |
| 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 htb_prio *hprio, const int prio) |
| { |
| int i; |
| struct { |
| struct rb_node *root; |
| struct rb_node **pptr; |
| u32 *pid; |
| } stk[TC_HTB_MAXDEPTH], *sp = stk; |
| |
| BUG_ON(!hprio->row.rb_node); |
| sp->root = hprio->row.rb_node; |
| sp->pptr = &hprio->ptr; |
| sp->pid = &hprio->last_ptr_id; |
| |
| 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--; |
| if (!*sp->pptr) { |
| WARN_ON(1); |
| return NULL; |
| } |
| htb_next_rb_node(sp->pptr); |
| } |
| } else { |
| struct htb_class *cl; |
| struct htb_prio *clp; |
| |
| cl = rb_entry(*sp->pptr, struct htb_class, node[prio]); |
| if (!cl->level) |
| return cl; |
| clp = &cl->inner.clprio[prio]; |
| (++sp)->root = clp->feed.rb_node; |
| sp->pptr = &clp->ptr; |
| sp->pid = &clp->last_ptr_id; |
| } |
| } |
| WARN_ON(1); |
| 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, const int prio, |
| const int level) |
| { |
| struct sk_buff *skb = NULL; |
| struct htb_class *cl, *start; |
| struct htb_level *hlevel = &q->hlevel[level]; |
| struct htb_prio *hprio = &hlevel->hprio[prio]; |
| |
| /* look initial class up in the row */ |
| start = cl = htb_lookup_leaf(hprio, prio); |
| |
| do { |
| next: |
| if (unlikely(!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->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(hprio, prio); |
| |
| if (cl == start) /* fix start if we just deleted it */ |
| start = next; |
| cl = next; |
| goto next; |
| } |
| |
| skb = cl->leaf.q->dequeue(cl->leaf.q); |
| if (likely(skb != NULL)) |
| break; |
| |
| qdisc_warn_nonwc("htb", cl->leaf.q); |
| htb_next_rb_node(level ? &cl->parent->inner.clprio[prio].ptr: |
| &q->hlevel[0].hprio[prio].ptr); |
| cl = htb_lookup_leaf(hprio, prio); |
| |
| } while (cl != start); |
| |
| if (likely(skb != NULL)) { |
| bstats_update(&cl->bstats, skb); |
| cl->leaf.deficit[level] -= qdisc_pkt_len(skb); |
| if (cl->leaf.deficit[level] < 0) { |
| cl->leaf.deficit[level] += cl->quantum; |
| htb_next_rb_node(level ? &cl->parent->inner.clprio[prio].ptr : |
| &q->hlevel[0].hprio[prio].ptr); |
| } |
| /* this used to be after charge_class but this constelation |
| * gives us slightly better performance |
| */ |
| if (!cl->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; |
| struct htb_sched *q = qdisc_priv(sch); |
| int level; |
| s64 next_event; |
| unsigned long start_at; |
| |
| /* try to dequeue direct packets as high prio (!) to minimize cpu work */ |
| skb = __qdisc_dequeue_head(&q->direct_queue); |
| if (skb != NULL) { |
| ok: |
| qdisc_bstats_update(sch, skb); |
| qdisc_qstats_backlog_dec(sch, skb); |
| sch->q.qlen--; |
| return skb; |
| } |
| |
| if (!sch->q.qlen) |
| goto fin; |
| q->now = ktime_get_ns(); |
| start_at = jiffies; |
| |
| next_event = q->now + 5LLU * NSEC_PER_SEC; |
| |
| for (level = 0; level < TC_HTB_MAXDEPTH; level++) { |
| /* common case optimization - skip event handler quickly */ |
| int m; |
| s64 event = q->near_ev_cache[level]; |
| |
| if (q->now >= event) { |
| event = htb_do_events(q, level, start_at); |
| if (!event) |
| event = q->now + NSEC_PER_SEC; |
| q->near_ev_cache[level] = event; |
| } |
| |
| if (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)) |
| goto ok; |
| } |
| } |
| if (likely(next_event > q->now)) |
| qdisc_watchdog_schedule_ns(&q->watchdog, next_event); |
| else |
| schedule_work(&q->work); |
| fin: |
| return skb; |
| } |
| |
| /* reset all classes */ |
| /* always caled under BH & queue lock */ |
| static void htb_reset(struct Qdisc *sch) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| struct htb_class *cl; |
| unsigned int i; |
| |
| for (i = 0; i < q->clhash.hashsize; i++) { |
| hlist_for_each_entry(cl, &q->clhash.hash[i], common.hnode) { |
| if (cl->level) |
| memset(&cl->inner, 0, sizeof(cl->inner)); |
| else { |
| if (cl->leaf.q && !q->offload) |
| qdisc_reset(cl->leaf.q); |
| } |
| cl->prio_activity = 0; |
| cl->cmode = HTB_CAN_SEND; |
| } |
| } |
| qdisc_watchdog_cancel(&q->watchdog); |
| __qdisc_reset_queue(&q->direct_queue); |
| sch->q.qlen = 0; |
| sch->qstats.backlog = 0; |
| memset(q->hlevel, 0, sizeof(q->hlevel)); |
| memset(q->row_mask, 0, sizeof(q->row_mask)); |
| } |
| |
| 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 }, |
| [TCA_HTB_DIRECT_QLEN] = { .type = NLA_U32 }, |
| [TCA_HTB_RATE64] = { .type = NLA_U64 }, |
| [TCA_HTB_CEIL64] = { .type = NLA_U64 }, |
| [TCA_HTB_OFFLOAD] = { .type = NLA_FLAG }, |
| }; |
| |
| static void htb_work_func(struct work_struct *work) |
| { |
| struct htb_sched *q = container_of(work, struct htb_sched, work); |
| struct Qdisc *sch = q->watchdog.qdisc; |
| |
| rcu_read_lock(); |
| __netif_schedule(qdisc_root(sch)); |
| rcu_read_unlock(); |
| } |
| |
| static void htb_set_lockdep_class_child(struct Qdisc *q) |
| { |
| static struct lock_class_key child_key; |
| |
| lockdep_set_class(qdisc_lock(q), &child_key); |
| } |
| |
| static int htb_offload(struct net_device *dev, struct tc_htb_qopt_offload *opt) |
| { |
| return dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_HTB, opt); |
| } |
| |
| static int htb_init(struct Qdisc *sch, struct nlattr *opt, |
| struct netlink_ext_ack *extack) |
| { |
| struct net_device *dev = qdisc_dev(sch); |
| struct tc_htb_qopt_offload offload_opt; |
| struct htb_sched *q = qdisc_priv(sch); |
| struct nlattr *tb[TCA_HTB_MAX + 1]; |
| struct tc_htb_glob *gopt; |
| unsigned int ntx; |
| int err; |
| |
| qdisc_watchdog_init(&q->watchdog, sch); |
| INIT_WORK(&q->work, htb_work_func); |
| |
| if (!opt) |
| return -EINVAL; |
| |
| err = tcf_block_get(&q->block, &q->filter_list, sch, extack); |
| if (err) |
| return err; |
| |
| err = nla_parse_nested_deprecated(tb, TCA_HTB_MAX, opt, htb_policy, |
| NULL); |
| if (err < 0) |
| return err; |
| |
| if (!tb[TCA_HTB_INIT]) |
| return -EINVAL; |
| |
| gopt = nla_data(tb[TCA_HTB_INIT]); |
| if (gopt->version != HTB_VER >> 16) |
| return -EINVAL; |
| |
| q->offload = nla_get_flag(tb[TCA_HTB_OFFLOAD]); |
| |
| if (q->offload) { |
| if (sch->parent != TC_H_ROOT) |
| return -EOPNOTSUPP; |
| |
| if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc) |
| return -EOPNOTSUPP; |
| |
| q->num_direct_qdiscs = dev->real_num_tx_queues; |
| q->direct_qdiscs = kcalloc(q->num_direct_qdiscs, |
| sizeof(*q->direct_qdiscs), |
| GFP_KERNEL); |
| if (!q->direct_qdiscs) |
| return -ENOMEM; |
| } |
| |
| err = qdisc_class_hash_init(&q->clhash); |
| if (err < 0) |
| goto err_free_direct_qdiscs; |
| |
| qdisc_skb_head_init(&q->direct_queue); |
| |
| if (tb[TCA_HTB_DIRECT_QLEN]) |
| q->direct_qlen = nla_get_u32(tb[TCA_HTB_DIRECT_QLEN]); |
| else |
| q->direct_qlen = qdisc_dev(sch)->tx_queue_len; |
| |
| if ((q->rate2quantum = gopt->rate2quantum) < 1) |
| q->rate2quantum = 1; |
| q->defcls = gopt->defcls; |
| |
| if (!q->offload) |
| return 0; |
| |
| for (ntx = 0; ntx < q->num_direct_qdiscs; ntx++) { |
| struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, ntx); |
| struct Qdisc *qdisc; |
| |
| qdisc = qdisc_create_dflt(dev_queue, &pfifo_qdisc_ops, |
| TC_H_MAKE(sch->handle, 0), extack); |
| if (!qdisc) { |
| err = -ENOMEM; |
| goto err_free_qdiscs; |
| } |
| |
| htb_set_lockdep_class_child(qdisc); |
| q->direct_qdiscs[ntx] = qdisc; |
| qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT; |
| } |
| |
| sch->flags |= TCQ_F_MQROOT; |
| |
| offload_opt = (struct tc_htb_qopt_offload) { |
| .command = TC_HTB_CREATE, |
| .parent_classid = TC_H_MAJ(sch->handle) >> 16, |
| .classid = TC_H_MIN(q->defcls), |
| .extack = extack, |
| }; |
| err = htb_offload(dev, &offload_opt); |
| if (err) |
| goto err_free_qdiscs; |
| |
| return 0; |
| |
| err_free_qdiscs: |
| /* TC_HTB_CREATE call failed, avoid any further calls to the driver. */ |
| q->offload = false; |
| |
| for (ntx = 0; ntx < q->num_direct_qdiscs && q->direct_qdiscs[ntx]; |
| ntx++) |
| qdisc_put(q->direct_qdiscs[ntx]); |
| |
| qdisc_class_hash_destroy(&q->clhash); |
| /* Prevent use-after-free and double-free when htb_destroy gets called. |
| */ |
| q->clhash.hash = NULL; |
| q->clhash.hashsize = 0; |
| |
| err_free_direct_qdiscs: |
| kfree(q->direct_qdiscs); |
| q->direct_qdiscs = NULL; |
| return err; |
| } |
| |
| static void htb_attach_offload(struct Qdisc *sch) |
| { |
| struct net_device *dev = qdisc_dev(sch); |
| struct htb_sched *q = qdisc_priv(sch); |
| unsigned int ntx; |
| |
| for (ntx = 0; ntx < q->num_direct_qdiscs; ntx++) { |
| struct Qdisc *old, *qdisc = q->direct_qdiscs[ntx]; |
| |
| old = dev_graft_qdisc(qdisc->dev_queue, qdisc); |
| qdisc_put(old); |
| qdisc_hash_add(qdisc, false); |
| } |
| for (ntx = q->num_direct_qdiscs; ntx < dev->num_tx_queues; ntx++) { |
| struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, ntx); |
| struct Qdisc *old = dev_graft_qdisc(dev_queue, NULL); |
| |
| qdisc_put(old); |
| } |
| |
| kfree(q->direct_qdiscs); |
| q->direct_qdiscs = NULL; |
| } |
| |
| static void htb_attach_software(struct Qdisc *sch) |
| { |
| struct net_device *dev = qdisc_dev(sch); |
| unsigned int ntx; |
| |
| /* Resemble qdisc_graft behavior. */ |
| for (ntx = 0; ntx < dev->num_tx_queues; ntx++) { |
| struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, ntx); |
| struct Qdisc *old = dev_graft_qdisc(dev_queue, sch); |
| |
| qdisc_refcount_inc(sch); |
| |
| qdisc_put(old); |
| } |
| } |
| |
| static void htb_attach(struct Qdisc *sch) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| |
| if (q->offload) |
| htb_attach_offload(sch); |
| else |
| htb_attach_software(sch); |
| } |
| |
| 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; |
| |
| if (q->offload) |
| sch->flags |= TCQ_F_OFFLOADED; |
| else |
| sch->flags &= ~TCQ_F_OFFLOADED; |
| |
| sch->qstats.overlimits = q->overlimits; |
| /* Its safe to not acquire qdisc lock. As we hold RTNL, |
| * no change can happen on the qdisc parameters. |
| */ |
| |
| 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_noflag(skb, TCA_OPTIONS); |
| if (nest == NULL) |
| goto nla_put_failure; |
| if (nla_put(skb, TCA_HTB_INIT, sizeof(gopt), &gopt) || |
| nla_put_u32(skb, TCA_HTB_DIRECT_QLEN, q->direct_qlen)) |
| goto nla_put_failure; |
| if (q->offload && nla_put_flag(skb, TCA_HTB_OFFLOAD)) |
| goto nla_put_failure; |
| |
| return nla_nest_end(skb, nest); |
| |
| nla_put_failure: |
| 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 htb_sched *q = qdisc_priv(sch); |
| struct nlattr *nest; |
| struct tc_htb_opt opt; |
| |
| /* Its safe to not acquire qdisc lock. As we hold RTNL, |
| * no change can happen on the class parameters. |
| */ |
| tcm->tcm_parent = cl->parent ? cl->parent->common.classid : TC_H_ROOT; |
| tcm->tcm_handle = cl->common.classid; |
| if (!cl->level && cl->leaf.q) |
| tcm->tcm_info = cl->leaf.q->handle; |
| |
| nest = nla_nest_start_noflag(skb, TCA_OPTIONS); |
| if (nest == NULL) |
| goto nla_put_failure; |
| |
| memset(&opt, 0, sizeof(opt)); |
| |
| psched_ratecfg_getrate(&opt.rate, &cl->rate); |
| opt.buffer = PSCHED_NS2TICKS(cl->buffer); |
| psched_ratecfg_getrate(&opt.ceil, &cl->ceil); |
| opt.cbuffer = PSCHED_NS2TICKS(cl->cbuffer); |
| opt.quantum = cl->quantum; |
| opt.prio = cl->prio; |
| opt.level = cl->level; |
| if (nla_put(skb, TCA_HTB_PARMS, sizeof(opt), &opt)) |
| goto nla_put_failure; |
| if (q->offload && nla_put_flag(skb, TCA_HTB_OFFLOAD)) |
| goto nla_put_failure; |
| if ((cl->rate.rate_bytes_ps >= (1ULL << 32)) && |
| nla_put_u64_64bit(skb, TCA_HTB_RATE64, cl->rate.rate_bytes_ps, |
| TCA_HTB_PAD)) |
| goto nla_put_failure; |
| if ((cl->ceil.rate_bytes_ps >= (1ULL << 32)) && |
| nla_put_u64_64bit(skb, TCA_HTB_CEIL64, cl->ceil.rate_bytes_ps, |
| TCA_HTB_PAD)) |
| goto nla_put_failure; |
| |
| return nla_nest_end(skb, nest); |
| |
| nla_put_failure: |
| nla_nest_cancel(skb, nest); |
| return -1; |
| } |
| |
| static void htb_offload_aggregate_stats(struct htb_sched *q, |
| struct htb_class *cl) |
| { |
| struct htb_class *c; |
| unsigned int i; |
| |
| memset(&cl->bstats, 0, sizeof(cl->bstats)); |
| |
| for (i = 0; i < q->clhash.hashsize; i++) { |
| hlist_for_each_entry(c, &q->clhash.hash[i], common.hnode) { |
| struct htb_class *p = c; |
| |
| while (p && p->level < cl->level) |
| p = p->parent; |
| |
| if (p != cl) |
| continue; |
| |
| cl->bstats.bytes += c->bstats_bias.bytes; |
| cl->bstats.packets += c->bstats_bias.packets; |
| if (c->level == 0) { |
| cl->bstats.bytes += c->leaf.q->bstats.bytes; |
| cl->bstats.packets += c->leaf.q->bstats.packets; |
| } |
| } |
| } |
| } |
| |
| static int |
| htb_dump_class_stats(struct Qdisc *sch, unsigned long arg, struct gnet_dump *d) |
| { |
| struct htb_class *cl = (struct htb_class *)arg; |
| struct htb_sched *q = qdisc_priv(sch); |
| struct gnet_stats_queue qs = { |
| .drops = cl->drops, |
| .overlimits = cl->overlimits, |
| }; |
| __u32 qlen = 0; |
| |
| if (!cl->level && cl->leaf.q) |
| qdisc_qstats_qlen_backlog(cl->leaf.q, &qlen, &qs.backlog); |
| |
| cl->xstats.tokens = clamp_t(s64, PSCHED_NS2TICKS(cl->tokens), |
| INT_MIN, INT_MAX); |
| cl->xstats.ctokens = clamp_t(s64, PSCHED_NS2TICKS(cl->ctokens), |
| INT_MIN, INT_MAX); |
| |
| if (q->offload) { |
| if (!cl->level) { |
| if (cl->leaf.q) |
| cl->bstats = cl->leaf.q->bstats; |
| else |
| memset(&cl->bstats, 0, sizeof(cl->bstats)); |
| cl->bstats.bytes += cl->bstats_bias.bytes; |
| cl->bstats.packets += cl->bstats_bias.packets; |
| } else { |
| htb_offload_aggregate_stats(q, cl); |
| } |
| } |
| |
| if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch), |
| d, NULL, &cl->bstats) < 0 || |
| gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 || |
| gnet_stats_copy_queue(d, NULL, &qs, qlen) < 0) |
| return -1; |
| |
| return gnet_stats_copy_app(d, &cl->xstats, sizeof(cl->xstats)); |
| } |
| |
| static struct netdev_queue * |
| htb_select_queue(struct Qdisc *sch, struct tcmsg *tcm) |
| { |
| struct net_device *dev = qdisc_dev(sch); |
| struct tc_htb_qopt_offload offload_opt; |
| struct htb_sched *q = qdisc_priv(sch); |
| int err; |
| |
| if (!q->offload) |
| return sch->dev_queue; |
| |
| offload_opt = (struct tc_htb_qopt_offload) { |
| .command = TC_HTB_LEAF_QUERY_QUEUE, |
| .classid = TC_H_MIN(tcm->tcm_parent), |
| }; |
| err = htb_offload(dev, &offload_opt); |
| if (err || offload_opt.qid >= dev->num_tx_queues) |
| return NULL; |
| return netdev_get_tx_queue(dev, offload_opt.qid); |
| } |
| |
| static struct Qdisc * |
| htb_graft_helper(struct netdev_queue *dev_queue, struct Qdisc *new_q) |
| { |
| struct net_device *dev = dev_queue->dev; |
| struct Qdisc *old_q; |
| |
| if (dev->flags & IFF_UP) |
| dev_deactivate(dev); |
| old_q = dev_graft_qdisc(dev_queue, new_q); |
| if (new_q) |
| new_q->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT; |
| if (dev->flags & IFF_UP) |
| dev_activate(dev); |
| |
| return old_q; |
| } |
| |
| static void htb_offload_move_qdisc(struct Qdisc *sch, u16 qid_old, u16 qid_new) |
| { |
| struct netdev_queue *queue_old, *queue_new; |
| struct net_device *dev = qdisc_dev(sch); |
| struct Qdisc *qdisc; |
| |
| queue_old = netdev_get_tx_queue(dev, qid_old); |
| queue_new = netdev_get_tx_queue(dev, qid_new); |
| |
| if (dev->flags & IFF_UP) |
| dev_deactivate(dev); |
| qdisc = dev_graft_qdisc(queue_old, NULL); |
| qdisc->dev_queue = queue_new; |
| qdisc = dev_graft_qdisc(queue_new, qdisc); |
| if (dev->flags & IFF_UP) |
| dev_activate(dev); |
| |
| WARN_ON(!(qdisc->flags & TCQ_F_BUILTIN)); |
| } |
| |
| static int htb_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new, |
| struct Qdisc **old, struct netlink_ext_ack *extack) |
| { |
| struct netdev_queue *dev_queue = sch->dev_queue; |
| struct htb_class *cl = (struct htb_class *)arg; |
| struct htb_sched *q = qdisc_priv(sch); |
| struct Qdisc *old_q; |
| |
| if (cl->level) |
| return -EINVAL; |
| |
| if (q->offload) { |
| dev_queue = new->dev_queue; |
| WARN_ON(dev_queue != cl->leaf.q->dev_queue); |
| } |
| |
| if (!new) { |
| new = qdisc_create_dflt(dev_queue, &pfifo_qdisc_ops, |
| cl->common.classid, extack); |
| if (!new) |
| return -ENOBUFS; |
| } |
| |
| if (q->offload) { |
| htb_set_lockdep_class_child(new); |
| /* One ref for cl->leaf.q, the other for dev_queue->qdisc. */ |
| qdisc_refcount_inc(new); |
| old_q = htb_graft_helper(dev_queue, new); |
| } |
| |
| *old = qdisc_replace(sch, new, &cl->leaf.q); |
| |
| if (q->offload) { |
| WARN_ON(old_q != *old); |
| qdisc_put(old_q); |
| } |
| |
| return 0; |
| } |
| |
| static struct Qdisc *htb_leaf(struct Qdisc *sch, unsigned long arg) |
| { |
| struct htb_class *cl = (struct htb_class *)arg; |
| return !cl->level ? cl->leaf.q : NULL; |
| } |
| |
| static void htb_qlen_notify(struct Qdisc *sch, unsigned long arg) |
| { |
| struct htb_class *cl = (struct htb_class *)arg; |
| |
| htb_deactivate(qdisc_priv(sch), cl); |
| } |
| |
| static inline int htb_parent_last_child(struct htb_class *cl) |
| { |
| if (!cl->parent) |
| /* the root class */ |
| return 0; |
| if (cl->parent->children > 1) |
| /* not the last child */ |
| return 0; |
| return 1; |
| } |
| |
| static void htb_parent_to_leaf(struct Qdisc *sch, struct htb_class *cl, |
| struct Qdisc *new_q) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| struct htb_class *parent = cl->parent; |
| |
| WARN_ON(cl->level || !cl->leaf.q || cl->prio_activity); |
| |
| if (parent->cmode != HTB_CAN_SEND) |
| htb_safe_rb_erase(&parent->pq_node, |
| &q->hlevel[parent->level].wait_pq); |
| |
| parent->level = 0; |
| memset(&parent->inner, 0, sizeof(parent->inner)); |
| parent->leaf.q = new_q ? new_q : &noop_qdisc; |
| parent->tokens = parent->buffer; |
| parent->ctokens = parent->cbuffer; |
| parent->t_c = ktime_get_ns(); |
| parent->cmode = HTB_CAN_SEND; |
| } |
| |
| static void htb_parent_to_leaf_offload(struct Qdisc *sch, |
| struct netdev_queue *dev_queue, |
| struct Qdisc *new_q) |
| { |
| struct Qdisc *old_q; |
| |
| /* One ref for cl->leaf.q, the other for dev_queue->qdisc. */ |
| qdisc_refcount_inc(new_q); |
| old_q = htb_graft_helper(dev_queue, new_q); |
| WARN_ON(!(old_q->flags & TCQ_F_BUILTIN)); |
| } |
| |
| static int htb_destroy_class_offload(struct Qdisc *sch, struct htb_class *cl, |
| bool last_child, bool destroying, |
| struct netlink_ext_ack *extack) |
| { |
| struct tc_htb_qopt_offload offload_opt; |
| struct Qdisc *q = cl->leaf.q; |
| struct Qdisc *old = NULL; |
| int err; |
| |
| if (cl->level) |
| return -EINVAL; |
| |
| WARN_ON(!q); |
| if (!destroying) { |
| /* On destroy of HTB, two cases are possible: |
| * 1. q is a normal qdisc, but q->dev_queue has noop qdisc. |
| * 2. q is a noop qdisc (for nodes that were inner), |
| * q->dev_queue is noop_netdev_queue. |
| */ |
| old = htb_graft_helper(q->dev_queue, NULL); |
| WARN_ON(!old); |
| WARN_ON(old != q); |
| } |
| |
| if (cl->parent) { |
| cl->parent->bstats_bias.bytes += q->bstats.bytes; |
| cl->parent->bstats_bias.packets += q->bstats.packets; |
| } |
| |
| offload_opt = (struct tc_htb_qopt_offload) { |
| .command = !last_child ? TC_HTB_LEAF_DEL : |
| destroying ? TC_HTB_LEAF_DEL_LAST_FORCE : |
| TC_HTB_LEAF_DEL_LAST, |
| .classid = cl->common.classid, |
| .extack = extack, |
| }; |
| err = htb_offload(qdisc_dev(sch), &offload_opt); |
| |
| if (!err || destroying) |
| qdisc_put(old); |
| else |
| htb_graft_helper(q->dev_queue, old); |
| |
| if (last_child) |
| return err; |
| |
| if (!err && offload_opt.moved_qid != 0) { |
| if (destroying) |
| q->dev_queue = netdev_get_tx_queue(qdisc_dev(sch), |
| offload_opt.qid); |
| else |
| htb_offload_move_qdisc(sch, offload_opt.moved_qid, |
| offload_opt.qid); |
| } |
| |
| return err; |
| } |
| |
| static void htb_destroy_class(struct Qdisc *sch, struct htb_class *cl) |
| { |
| if (!cl->level) { |
| WARN_ON(!cl->leaf.q); |
| qdisc_put(cl->leaf.q); |
| } |
| gen_kill_estimator(&cl->rate_est); |
| tcf_block_put(cl->block); |
| kfree(cl); |
| } |
| |
| static void htb_destroy(struct Qdisc *sch) |
| { |
| struct net_device *dev = qdisc_dev(sch); |
| struct tc_htb_qopt_offload offload_opt; |
| struct htb_sched *q = qdisc_priv(sch); |
| struct hlist_node *next; |
| bool nonempty, changed; |
| struct htb_class *cl; |
| unsigned int i; |
| |
| cancel_work_sync(&q->work); |
| 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_block_put(q->block); |
| |
| for (i = 0; i < q->clhash.hashsize; i++) { |
| hlist_for_each_entry(cl, &q->clhash.hash[i], common.hnode) { |
| tcf_block_put(cl->block); |
| cl->block = NULL; |
| } |
| } |
| |
| do { |
| nonempty = false; |
| changed = false; |
| for (i = 0; i < q->clhash.hashsize; i++) { |
| hlist_for_each_entry_safe(cl, next, &q->clhash.hash[i], |
| common.hnode) { |
| bool last_child; |
| |
| if (!q->offload) { |
| htb_destroy_class(sch, cl); |
| continue; |
| } |
| |
| nonempty = true; |
| |
| if (cl->level) |
| continue; |
| |
| changed = true; |
| |
| last_child = htb_parent_last_child(cl); |
| htb_destroy_class_offload(sch, cl, last_child, |
| true, NULL); |
| qdisc_class_hash_remove(&q->clhash, |
| &cl->common); |
| if (cl->parent) |
| cl->parent->children--; |
| if (last_child) |
| htb_parent_to_leaf(sch, cl, NULL); |
| htb_destroy_class(sch, cl); |
| } |
| } |
| } while (changed); |
| WARN_ON(nonempty); |
| |
| qdisc_class_hash_destroy(&q->clhash); |
| __qdisc_reset_queue(&q->direct_queue); |
| |
| if (!q->offload) |
| return; |
| |
| offload_opt = (struct tc_htb_qopt_offload) { |
| .command = TC_HTB_DESTROY, |
| }; |
| htb_offload(dev, &offload_opt); |
| |
| if (!q->direct_qdiscs) |
| return; |
| for (i = 0; i < q->num_direct_qdiscs && q->direct_qdiscs[i]; i++) |
| qdisc_put(q->direct_qdiscs[i]); |
| kfree(q->direct_qdiscs); |
| } |
| |
| static int htb_delete(struct Qdisc *sch, unsigned long arg, |
| struct netlink_ext_ack *extack) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| struct htb_class *cl = (struct htb_class *)arg; |
| struct Qdisc *new_q = NULL; |
| int last_child = 0; |
| int err; |
| |
| /* TODO: why don't allow to delete subtree ? references ? does |
| * tc subsys guarantee us that in htb_destroy it holds no class |
| * refs so that we can remove children safely there ? |
| */ |
| if (cl->children || cl->filter_cnt) |
| return -EBUSY; |
| |
| if (!cl->level && htb_parent_last_child(cl)) |
| last_child = 1; |
| |
| if (q->offload) { |
| err = htb_destroy_class_offload(sch, cl, last_child, false, |
| extack); |
| if (err) |
| return err; |
| } |
| |
| if (last_child) { |
| struct netdev_queue *dev_queue; |
| |
| dev_queue = q->offload ? cl->leaf.q->dev_queue : sch->dev_queue; |
| new_q = qdisc_create_dflt(dev_queue, &pfifo_qdisc_ops, |
| cl->parent->common.classid, |
| NULL); |
| if (q->offload) { |
| if (new_q) |
| htb_set_lockdep_class_child(new_q); |
| htb_parent_to_leaf_offload(sch, dev_queue, new_q); |
| } |
| } |
| |
| sch_tree_lock(sch); |
| |
| if (!cl->level) |
| qdisc_purge_queue(cl->leaf.q); |
| |
| /* delete from hash and active; remainder in destroy_class */ |
| qdisc_class_hash_remove(&q->clhash, &cl->common); |
| if (cl->parent) |
| cl->parent->children--; |
| |
| if (cl->prio_activity) |
| htb_deactivate(q, cl); |
| |
| if (cl->cmode != HTB_CAN_SEND) |
| htb_safe_rb_erase(&cl->pq_node, |
| &q->hlevel[cl->level].wait_pq); |
| |
| if (last_child) |
| htb_parent_to_leaf(sch, cl, new_q); |
| |
| sch_tree_unlock(sch); |
| |
| htb_destroy_class(sch, cl); |
| return 0; |
| } |
| |
| static int htb_change_class(struct Qdisc *sch, u32 classid, |
| u32 parentid, struct nlattr **tca, |
| unsigned long *arg, struct netlink_ext_ack *extack) |
| { |
| int err = -EINVAL; |
| struct htb_sched *q = qdisc_priv(sch); |
| struct htb_class *cl = (struct htb_class *)*arg, *parent; |
| struct tc_htb_qopt_offload offload_opt; |
| struct nlattr *opt = tca[TCA_OPTIONS]; |
| struct nlattr *tb[TCA_HTB_MAX + 1]; |
| struct Qdisc *parent_qdisc = NULL; |
| struct netdev_queue *dev_queue; |
| struct tc_htb_opt *hopt; |
| u64 rate64, ceil64; |
| int warn = 0; |
| |
| /* extract all subattrs from opt attr */ |
| if (!opt) |
| goto failure; |
| |
| err = nla_parse_nested_deprecated(tb, TCA_HTB_MAX, opt, htb_policy, |
| NULL); |
| 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]); |
| if (!hopt->rate.rate || !hopt->ceil.rate) |
| goto failure; |
| |
| /* Keeping backward compatible with rate_table based iproute2 tc */ |
| if (hopt->rate.linklayer == TC_LINKLAYER_UNAWARE) |
| qdisc_put_rtab(qdisc_get_rtab(&hopt->rate, tb[TCA_HTB_RTAB], |
| NULL)); |
| |
| if (hopt->ceil.linklayer == TC_LINKLAYER_UNAWARE) |
| qdisc_put_rtab(qdisc_get_rtab(&hopt->ceil, tb[TCA_HTB_CTAB], |
| NULL)); |
| |
| rate64 = tb[TCA_HTB_RATE64] ? nla_get_u64(tb[TCA_HTB_RATE64]) : 0; |
| ceil64 = tb[TCA_HTB_CEIL64] ? nla_get_u64(tb[TCA_HTB_CEIL64]) : 0; |
| |
| if (!cl) { /* new class */ |
| struct net_device *dev = qdisc_dev(sch); |
| struct Qdisc *new_q, *old_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) { |
| pr_err("htb: tree is too deep\n"); |
| goto failure; |
| } |
| err = -ENOBUFS; |
| cl = kzalloc(sizeof(*cl), GFP_KERNEL); |
| if (!cl) |
| goto failure; |
| |
| err = tcf_block_get(&cl->block, &cl->filter_list, sch, extack); |
| if (err) { |
| kfree(cl); |
| goto failure; |
| } |
| if (htb_rate_est || tca[TCA_RATE]) { |
| err = gen_new_estimator(&cl->bstats, NULL, |
| &cl->rate_est, |
| NULL, |
| qdisc_root_sleeping_running(sch), |
| tca[TCA_RATE] ? : &est.nla); |
| if (err) |
| goto err_block_put; |
| } |
| |
| cl->children = 0; |
| RB_CLEAR_NODE(&cl->pq_node); |
| |
| for (prio = 0; prio < TC_HTB_NUMPRIO; prio++) |
| RB_CLEAR_NODE(&cl->node[prio]); |
| |
| cl->common.classid = classid; |
| |
| /* Make sure nothing interrupts us in between of two |
| * ndo_setup_tc calls. |
| */ |
| ASSERT_RTNL(); |
| |
| /* 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 |
| */ |
| if (!q->offload) { |
| dev_queue = sch->dev_queue; |
| } else if (!(parent && !parent->level)) { |
| /* Assign a dev_queue to this classid. */ |
| offload_opt = (struct tc_htb_qopt_offload) { |
| .command = TC_HTB_LEAF_ALLOC_QUEUE, |
| .classid = cl->common.classid, |
| .parent_classid = parent ? |
| TC_H_MIN(parent->common.classid) : |
| TC_HTB_CLASSID_ROOT, |
| .rate = max_t(u64, hopt->rate.rate, rate64), |
| .ceil = max_t(u64, hopt->ceil.rate, ceil64), |
| .extack = extack, |
| }; |
| err = htb_offload(dev, &offload_opt); |
| if (err) { |
| pr_err("htb: TC_HTB_LEAF_ALLOC_QUEUE failed with err = %d\n", |
| err); |
| goto err_kill_estimator; |
| } |
| dev_queue = netdev_get_tx_queue(dev, offload_opt.qid); |
| } else { /* First child. */ |
| dev_queue = parent->leaf.q->dev_queue; |
| old_q = htb_graft_helper(dev_queue, NULL); |
| WARN_ON(old_q != parent->leaf.q); |
| offload_opt = (struct tc_htb_qopt_offload) { |
| .command = TC_HTB_LEAF_TO_INNER, |
| .classid = cl->common.classid, |
| .parent_classid = |
| TC_H_MIN(parent->common.classid), |
| .rate = max_t(u64, hopt->rate.rate, rate64), |
| .ceil = max_t(u64, hopt->ceil.rate, ceil64), |
| .extack = extack, |
| }; |
| err = htb_offload(dev, &offload_opt); |
| if (err) { |
| pr_err("htb: TC_HTB_LEAF_TO_INNER failed with err = %d\n", |
| err); |
| htb_graft_helper(dev_queue, old_q); |
| goto err_kill_estimator; |
| } |
| parent->bstats_bias.bytes += old_q->bstats.bytes; |
| parent->bstats_bias.packets += old_q->bstats.packets; |
| qdisc_put(old_q); |
| } |
| new_q = qdisc_create_dflt(dev_queue, &pfifo_qdisc_ops, |
| classid, NULL); |
| if (q->offload) { |
| if (new_q) { |
| htb_set_lockdep_class_child(new_q); |
| /* One ref for cl->leaf.q, the other for |
| * dev_queue->qdisc. |
| */ |
| qdisc_refcount_inc(new_q); |
| } |
| old_q = htb_graft_helper(dev_queue, new_q); |
| /* No qdisc_put needed. */ |
| WARN_ON(!(old_q->flags & TCQ_F_BUILTIN)); |
| } |
| sch_tree_lock(sch); |
| if (parent && !parent->level) { |
| /* turn parent into inner node */ |
| qdisc_purge_queue(parent->leaf.q); |
| parent_qdisc = parent->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->hlevel[0].wait_pq); |
| parent->cmode = HTB_CAN_SEND; |
| } |
| parent->level = (parent->parent ? parent->parent->level |
| : TC_HTB_MAXDEPTH) - 1; |
| memset(&parent->inner, 0, sizeof(parent->inner)); |
| } |
| |
| /* leaf (we) needs elementary qdisc */ |
| cl->leaf.q = new_q ? new_q : &noop_qdisc; |
| |
| cl->parent = parent; |
| |
| /* set class to be in HTB_CAN_SEND state */ |
| cl->tokens = PSCHED_TICKS2NS(hopt->buffer); |
| cl->ctokens = PSCHED_TICKS2NS(hopt->cbuffer); |
| cl->mbuffer = 60ULL * NSEC_PER_SEC; /* 1min */ |
| cl->t_c = ktime_get_ns(); |
| cl->cmode = HTB_CAN_SEND; |
| |
| /* attach to the hash list and parent's family */ |
| qdisc_class_hash_insert(&q->clhash, &cl->common); |
| if (parent) |
| parent->children++; |
| if (cl->leaf.q != &noop_qdisc) |
| qdisc_hash_add(cl->leaf.q, true); |
| } else { |
| if (tca[TCA_RATE]) { |
| err = gen_replace_estimator(&cl->bstats, NULL, |
| &cl->rate_est, |
| NULL, |
| qdisc_root_sleeping_running(sch), |
| tca[TCA_RATE]); |
| if (err) |
| return err; |
| } |
| |
| if (q->offload) { |
| struct net_device *dev = qdisc_dev(sch); |
| |
| offload_opt = (struct tc_htb_qopt_offload) { |
| .command = TC_HTB_NODE_MODIFY, |
| .classid = cl->common.classid, |
| .rate = max_t(u64, hopt->rate.rate, rate64), |
| .ceil = max_t(u64, hopt->ceil.rate, ceil64), |
| .extack = extack, |
| }; |
| err = htb_offload(dev, &offload_opt); |
| if (err) |
| /* Estimator was replaced, and rollback may fail |
| * as well, so we don't try to recover it, and |
| * the estimator won't work property with the |
| * offload anyway, because bstats are updated |
| * only when the stats are queried. |
| */ |
| return err; |
| } |
| |
| sch_tree_lock(sch); |
| } |
| |
| psched_ratecfg_precompute(&cl->rate, &hopt->rate, rate64); |
| psched_ratecfg_precompute(&cl->ceil, &hopt->ceil, ceil64); |
| |
| /* it used to be a nasty bug here, we have to check that node |
| * is really leaf before changing cl->leaf ! |
| */ |
| if (!cl->level) { |
| u64 quantum = cl->rate.rate_bytes_ps; |
| |
| do_div(quantum, q->rate2quantum); |
| cl->quantum = min_t(u64, quantum, INT_MAX); |
| |
| if (!hopt->quantum && cl->quantum < 1000) { |
| warn = -1; |
| cl->quantum = 1000; |
| } |
| if (!hopt->quantum && cl->quantum > 200000) { |
| warn = 1; |
| cl->quantum = 200000; |
| } |
| if (hopt->quantum) |
| cl->quantum = hopt->quantum; |
| if ((cl->prio = hopt->prio) >= TC_HTB_NUMPRIO) |
| cl->prio = TC_HTB_NUMPRIO - 1; |
| } |
| |
| cl->buffer = PSCHED_TICKS2NS(hopt->buffer); |
| cl->cbuffer = PSCHED_TICKS2NS(hopt->cbuffer); |
| |
| sch_tree_unlock(sch); |
| qdisc_put(parent_qdisc); |
| |
| if (warn) |
| pr_warn("HTB: quantum of class %X is %s. Consider r2q change.\n", |
| cl->common.classid, (warn == -1 ? "small" : "big")); |
| |
| qdisc_class_hash_grow(sch, &q->clhash); |
| |
| *arg = (unsigned long)cl; |
| return 0; |
| |
| err_kill_estimator: |
| gen_kill_estimator(&cl->rate_est); |
| err_block_put: |
| tcf_block_put(cl->block); |
| kfree(cl); |
| failure: |
| return err; |
| } |
| |
| static struct tcf_block *htb_tcf_block(struct Qdisc *sch, unsigned long arg, |
| struct netlink_ext_ack *extack) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| struct htb_class *cl = (struct htb_class *)arg; |
| |
| return cl ? cl->block : q->block; |
| } |
| |
| static unsigned long htb_bind_filter(struct Qdisc *sch, unsigned long parent, |
| u32 classid) |
| { |
| 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++; |
| return (unsigned long)cl; |
| } |
| |
| static void htb_unbind_filter(struct Qdisc *sch, unsigned long arg) |
| { |
| struct htb_class *cl = (struct htb_class *)arg; |
| |
| if (cl) |
| cl->filter_cnt--; |
| } |
| |
| static void htb_walk(struct Qdisc *sch, struct qdisc_walker *arg) |
| { |
| struct htb_sched *q = qdisc_priv(sch); |
| struct htb_class *cl; |
| unsigned int i; |
| |
| if (arg->stop) |
| return; |
| |
| for (i = 0; i < q->clhash.hashsize; i++) { |
| hlist_for_each_entry(cl, &q->clhash.hash[i], common.hnode) { |
| 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 = { |
| .select_queue = htb_select_queue, |
| .graft = htb_graft, |
| .leaf = htb_leaf, |
| .qlen_notify = htb_qlen_notify, |
| .find = htb_search, |
| .change = htb_change_class, |
| .delete = htb_delete, |
| .walk = htb_walk, |
| .tcf_block = htb_tcf_block, |
| .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 = { |
| .cl_ops = &htb_class_ops, |
| .id = "htb", |
| .priv_size = sizeof(struct htb_sched), |
| .enqueue = htb_enqueue, |
| .dequeue = htb_dequeue, |
| .peek = qdisc_peek_dequeued, |
| .init = htb_init, |
| .attach = htb_attach, |
| .reset = htb_reset, |
| .destroy = htb_destroy, |
| .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"); |