![Florian Westphal](/assets/img/avatar_default.png)
This change replaces sk_buff_head struct in Qdiscs with new qdisc_skb_head. Its similar to the skb_buff_head api, but does not use skb->prev pointers. Qdiscs will commonly enqueue at the tail of a list and dequeue at head. While skb_buff_head works fine for this, enqueue/dequeue needs to also adjust the prev pointer of next element. The ->prev pointer is not required for qdiscs so we can just leave it undefined and avoid one cacheline write access for en/dequeue. Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
1624 lines
43 KiB
C
1624 lines
43 KiB
C
/*
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* net/sched/sch_htb.c Hierarchical token bucket, feed tree version
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* Authors: Martin Devera, <devik@cdi.cz>
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*
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* Credits (in time order) for older HTB versions:
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* Stef Coene <stef.coene@docum.org>
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* HTB support at LARTC mailing list
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* Ondrej Kraus, <krauso@barr.cz>
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* found missing INIT_QDISC(htb)
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* Vladimir Smelhaus, Aamer Akhter, Bert Hubert
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* helped a lot to locate nasty class stall bug
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* Andi Kleen, Jamal Hadi, Bert Hubert
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* code review and helpful comments on shaping
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* Tomasz Wrona, <tw@eter.tym.pl>
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* created test case so that I was able to fix nasty bug
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* Wilfried Weissmann
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* spotted bug in dequeue code and helped with fix
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* Jiri Fojtasek
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* fixed requeue routine
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* and many others. thanks.
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*/
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#include <linux/module.h>
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#include <linux/moduleparam.h>
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/string.h>
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#include <linux/errno.h>
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#include <linux/skbuff.h>
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#include <linux/list.h>
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#include <linux/compiler.h>
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#include <linux/rbtree.h>
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#include <linux/workqueue.h>
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#include <linux/slab.h>
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#include <net/netlink.h>
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#include <net/sch_generic.h>
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#include <net/pkt_sched.h>
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/* HTB algorithm.
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Author: devik@cdi.cz
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========================================================================
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HTB is like TBF with multiple classes. It is also similar to CBQ because
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it allows to assign priority to each class in hierarchy.
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In fact it is another implementation of Floyd's formal sharing.
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Levels:
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Each class is assigned level. Leaf has ALWAYS level 0 and root
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classes have level TC_HTB_MAXDEPTH-1. Interior nodes has level
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one less than their parent.
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*/
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static int htb_hysteresis __read_mostly = 0; /* whether to use mode hysteresis for speedup */
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#define HTB_VER 0x30011 /* major must be matched with number suplied by TC as version */
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#if HTB_VER >> 16 != TC_HTB_PROTOVER
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#error "Mismatched sch_htb.c and pkt_sch.h"
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#endif
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/* Module parameter and sysfs export */
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module_param (htb_hysteresis, int, 0640);
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MODULE_PARM_DESC(htb_hysteresis, "Hysteresis mode, less CPU load, less accurate");
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static int htb_rate_est = 0; /* htb classes have a default rate estimator */
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module_param(htb_rate_est, int, 0640);
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MODULE_PARM_DESC(htb_rate_est, "setup a default rate estimator (4sec 16sec) for htb classes");
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/* used internaly to keep status of single class */
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enum htb_cmode {
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HTB_CANT_SEND, /* class can't send and can't borrow */
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HTB_MAY_BORROW, /* class can't send but may borrow */
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HTB_CAN_SEND /* class can send */
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};
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struct htb_prio {
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union {
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struct rb_root row;
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struct rb_root feed;
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};
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struct rb_node *ptr;
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/* When class changes from state 1->2 and disconnects from
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* parent's feed then we lost ptr value and start from the
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* first child again. Here we store classid of the
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* last valid ptr (used when ptr is NULL).
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*/
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u32 last_ptr_id;
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};
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/* interior & leaf nodes; props specific to leaves are marked L:
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* To reduce false sharing, place mostly read fields at beginning,
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* and mostly written ones at the end.
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*/
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struct htb_class {
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struct Qdisc_class_common common;
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struct psched_ratecfg rate;
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struct psched_ratecfg ceil;
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s64 buffer, cbuffer;/* token bucket depth/rate */
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s64 mbuffer; /* max wait time */
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u32 prio; /* these two are used only by leaves... */
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int quantum; /* but stored for parent-to-leaf return */
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struct tcf_proto __rcu *filter_list; /* class attached filters */
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int filter_cnt;
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int refcnt; /* usage count of this class */
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int level; /* our level (see above) */
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unsigned int children;
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struct htb_class *parent; /* parent class */
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struct gnet_stats_rate_est64 rate_est;
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/*
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* Written often fields
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*/
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struct gnet_stats_basic_packed bstats;
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struct tc_htb_xstats xstats; /* our special stats */
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/* token bucket parameters */
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s64 tokens, ctokens;/* current number of tokens */
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s64 t_c; /* checkpoint time */
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union {
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struct htb_class_leaf {
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struct list_head drop_list;
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int deficit[TC_HTB_MAXDEPTH];
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struct Qdisc *q;
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} leaf;
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struct htb_class_inner {
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struct htb_prio clprio[TC_HTB_NUMPRIO];
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} inner;
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} un;
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s64 pq_key;
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int prio_activity; /* for which prios are we active */
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enum htb_cmode cmode; /* current mode of the class */
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struct rb_node pq_node; /* node for event queue */
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struct rb_node node[TC_HTB_NUMPRIO]; /* node for self or feed tree */
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unsigned int drops ____cacheline_aligned_in_smp;
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};
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struct htb_level {
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struct rb_root wait_pq;
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struct htb_prio hprio[TC_HTB_NUMPRIO];
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};
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struct htb_sched {
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struct Qdisc_class_hash clhash;
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int defcls; /* class where unclassified flows go to */
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int rate2quantum; /* quant = rate / rate2quantum */
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/* filters for qdisc itself */
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struct tcf_proto __rcu *filter_list;
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#define HTB_WARN_TOOMANYEVENTS 0x1
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unsigned int warned; /* only one warning */
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int direct_qlen;
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struct work_struct work;
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/* non shaped skbs; let them go directly thru */
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struct qdisc_skb_head direct_queue;
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long direct_pkts;
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struct qdisc_watchdog watchdog;
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s64 now; /* cached dequeue time */
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struct list_head drops[TC_HTB_NUMPRIO];/* active leaves (for drops) */
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/* time of nearest event per level (row) */
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s64 near_ev_cache[TC_HTB_MAXDEPTH];
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int row_mask[TC_HTB_MAXDEPTH];
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struct htb_level hlevel[TC_HTB_MAXDEPTH];
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};
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/* find class in global hash table using given handle */
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static inline struct htb_class *htb_find(u32 handle, struct Qdisc *sch)
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{
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struct htb_sched *q = qdisc_priv(sch);
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struct Qdisc_class_common *clc;
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clc = qdisc_class_find(&q->clhash, handle);
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if (clc == NULL)
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return NULL;
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return container_of(clc, struct htb_class, common);
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}
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/**
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* htb_classify - classify a packet into class
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*
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* It returns NULL if the packet should be dropped or -1 if the packet
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* should be passed directly thru. In all other cases leaf class is returned.
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* We allow direct class selection by classid in priority. The we examine
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* filters in qdisc and in inner nodes (if higher filter points to the inner
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* node). If we end up with classid MAJOR:0 we enqueue the skb into special
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* internal fifo (direct). These packets then go directly thru. If we still
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* have no valid leaf we try to use MAJOR:default leaf. It still unsuccessful
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* then finish and return direct queue.
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*/
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#define HTB_DIRECT ((struct htb_class *)-1L)
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static struct htb_class *htb_classify(struct sk_buff *skb, struct Qdisc *sch,
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int *qerr)
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{
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struct htb_sched *q = qdisc_priv(sch);
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struct htb_class *cl;
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struct tcf_result res;
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struct tcf_proto *tcf;
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int result;
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/* allow to select class by setting skb->priority to valid classid;
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* note that nfmark can be used too by attaching filter fw with no
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* rules in it
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*/
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if (skb->priority == sch->handle)
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return HTB_DIRECT; /* X:0 (direct flow) selected */
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cl = htb_find(skb->priority, sch);
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if (cl) {
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if (cl->level == 0)
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return cl;
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/* Start with inner filter chain if a non-leaf class is selected */
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tcf = rcu_dereference_bh(cl->filter_list);
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} else {
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tcf = rcu_dereference_bh(q->filter_list);
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}
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*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
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while (tcf && (result = tc_classify(skb, tcf, &res, false)) >= 0) {
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#ifdef CONFIG_NET_CLS_ACT
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switch (result) {
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case TC_ACT_QUEUED:
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case TC_ACT_STOLEN:
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*qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
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case TC_ACT_SHOT:
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return NULL;
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}
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#endif
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cl = (void *)res.class;
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if (!cl) {
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if (res.classid == sch->handle)
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return HTB_DIRECT; /* X:0 (direct flow) */
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cl = htb_find(res.classid, sch);
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if (!cl)
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break; /* filter selected invalid classid */
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}
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if (!cl->level)
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return cl; /* we hit leaf; return it */
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/* we have got inner class; apply inner filter chain */
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tcf = rcu_dereference_bh(cl->filter_list);
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}
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/* classification failed; try to use default class */
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cl = htb_find(TC_H_MAKE(TC_H_MAJ(sch->handle), q->defcls), sch);
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if (!cl || cl->level)
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return HTB_DIRECT; /* bad default .. this is safe bet */
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return cl;
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}
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/**
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* htb_add_to_id_tree - adds class to the round robin list
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*
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* Routine adds class to the list (actually tree) sorted by classid.
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* Make sure that class is not already on such list for given prio.
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*/
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static void htb_add_to_id_tree(struct rb_root *root,
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struct htb_class *cl, int prio)
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{
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struct rb_node **p = &root->rb_node, *parent = NULL;
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while (*p) {
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struct htb_class *c;
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parent = *p;
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c = rb_entry(parent, struct htb_class, node[prio]);
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if (cl->common.classid > c->common.classid)
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p = &parent->rb_right;
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else
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p = &parent->rb_left;
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}
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rb_link_node(&cl->node[prio], parent, p);
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rb_insert_color(&cl->node[prio], root);
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}
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/**
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* htb_add_to_wait_tree - adds class to the event queue with delay
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*
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* The class is added to priority event queue to indicate that class will
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* change its mode in cl->pq_key microseconds. Make sure that class is not
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* already in the queue.
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*/
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static void htb_add_to_wait_tree(struct htb_sched *q,
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struct htb_class *cl, s64 delay)
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{
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struct rb_node **p = &q->hlevel[cl->level].wait_pq.rb_node, *parent = NULL;
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cl->pq_key = q->now + delay;
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if (cl->pq_key == q->now)
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cl->pq_key++;
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/* update the nearest event cache */
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if (q->near_ev_cache[cl->level] > cl->pq_key)
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q->near_ev_cache[cl->level] = cl->pq_key;
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while (*p) {
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struct htb_class *c;
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parent = *p;
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c = rb_entry(parent, struct htb_class, pq_node);
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if (cl->pq_key >= c->pq_key)
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p = &parent->rb_right;
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else
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p = &parent->rb_left;
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}
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rb_link_node(&cl->pq_node, parent, p);
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rb_insert_color(&cl->pq_node, &q->hlevel[cl->level].wait_pq);
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}
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/**
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* htb_next_rb_node - finds next node in binary tree
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*
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* When we are past last key we return NULL.
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* Average complexity is 2 steps per call.
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*/
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static inline void htb_next_rb_node(struct rb_node **n)
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{
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*n = rb_next(*n);
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}
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/**
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* htb_add_class_to_row - add class to its row
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*
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* The class is added to row at priorities marked in mask.
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* It does nothing if mask == 0.
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*/
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static inline void htb_add_class_to_row(struct htb_sched *q,
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struct htb_class *cl, int mask)
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{
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q->row_mask[cl->level] |= mask;
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while (mask) {
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int prio = ffz(~mask);
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mask &= ~(1 << prio);
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htb_add_to_id_tree(&q->hlevel[cl->level].hprio[prio].row, cl, prio);
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}
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}
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/* If this triggers, it is a bug in this code, but it need not be fatal */
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static void htb_safe_rb_erase(struct rb_node *rb, struct rb_root *root)
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{
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if (RB_EMPTY_NODE(rb)) {
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WARN_ON(1);
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} else {
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rb_erase(rb, root);
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RB_CLEAR_NODE(rb);
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}
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}
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/**
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* htb_remove_class_from_row - removes class from its row
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*
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* The class is removed from row at priorities marked in mask.
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* It does nothing if mask == 0.
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*/
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static inline void htb_remove_class_from_row(struct htb_sched *q,
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struct htb_class *cl, int mask)
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{
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int m = 0;
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struct htb_level *hlevel = &q->hlevel[cl->level];
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while (mask) {
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int prio = ffz(~mask);
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struct htb_prio *hprio = &hlevel->hprio[prio];
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mask &= ~(1 << prio);
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if (hprio->ptr == cl->node + prio)
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htb_next_rb_node(&hprio->ptr);
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htb_safe_rb_erase(cl->node + prio, &hprio->row);
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if (!hprio->row.rb_node)
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m |= 1 << prio;
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}
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q->row_mask[cl->level] &= ~m;
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}
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/**
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* htb_activate_prios - creates active classe's feed chain
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*
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* The class is connected to ancestors and/or appropriate rows
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* for priorities it is participating on. cl->cmode must be new
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* (activated) mode. It does nothing if cl->prio_activity == 0.
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*/
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static void htb_activate_prios(struct htb_sched *q, struct htb_class *cl)
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{
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struct htb_class *p = cl->parent;
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long m, mask = cl->prio_activity;
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while (cl->cmode == HTB_MAY_BORROW && p && mask) {
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m = mask;
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while (m) {
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int prio = ffz(~m);
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m &= ~(1 << prio);
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if (p->un.inner.clprio[prio].feed.rb_node)
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/* parent already has its feed in use so that
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* reset bit in mask as parent is already ok
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*/
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mask &= ~(1 << prio);
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htb_add_to_id_tree(&p->un.inner.clprio[prio].feed, cl, prio);
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}
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p->prio_activity |= mask;
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cl = p;
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p = cl->parent;
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}
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if (cl->cmode == HTB_CAN_SEND && mask)
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htb_add_class_to_row(q, cl, mask);
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}
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/**
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* htb_deactivate_prios - remove class from feed chain
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*
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* cl->cmode must represent old mode (before deactivation). It does
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* nothing if cl->prio_activity == 0. Class is removed from all feed
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* chains and rows.
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*/
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static void htb_deactivate_prios(struct htb_sched *q, struct htb_class *cl)
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{
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struct htb_class *p = cl->parent;
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long m, mask = cl->prio_activity;
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while (cl->cmode == HTB_MAY_BORROW && p && mask) {
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m = mask;
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mask = 0;
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while (m) {
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int prio = ffz(~m);
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m &= ~(1 << prio);
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if (p->un.inner.clprio[prio].ptr == cl->node + prio) {
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/* we are removing child which is pointed to from
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* parent feed - forget the pointer but remember
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* classid
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*/
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p->un.inner.clprio[prio].last_ptr_id = cl->common.classid;
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p->un.inner.clprio[prio].ptr = NULL;
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}
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htb_safe_rb_erase(cl->node + prio,
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&p->un.inner.clprio[prio].feed);
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if (!p->un.inner.clprio[prio].feed.rb_node)
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mask |= 1 << prio;
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}
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p->prio_activity &= ~mask;
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cl = p;
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p = cl->parent;
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}
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if (cl->cmode == HTB_CAN_SEND && mask)
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htb_remove_class_from_row(q, cl, mask);
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}
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static inline s64 htb_lowater(const struct htb_class *cl)
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{
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if (htb_hysteresis)
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return cl->cmode != HTB_CANT_SEND ? -cl->cbuffer : 0;
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else
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return 0;
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}
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static inline s64 htb_hiwater(const struct htb_class *cl)
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{
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if (htb_hysteresis)
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return cl->cmode == HTB_CAN_SEND ? -cl->buffer : 0;
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else
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return 0;
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}
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|
|
|
|
/**
|
|
* 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 (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->un.leaf.q || !cl->un.leaf.q->q.qlen);
|
|
|
|
if (!cl->prio_activity) {
|
|
cl->prio_activity = 1 << cl->prio;
|
|
htb_activate_prios(q, cl);
|
|
list_add_tail(&cl->un.leaf.drop_list,
|
|
q->drops + cl->prio);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* 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;
|
|
list_del_init(&cl->un.leaf.drop_list);
|
|
}
|
|
|
|
static void htb_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch,
|
|
struct qdisc_skb_head *qh)
|
|
{
|
|
struct sk_buff *last = qh->tail;
|
|
|
|
if (last) {
|
|
skb->next = NULL;
|
|
last->next = skb;
|
|
qh->tail = skb;
|
|
} else {
|
|
qh->tail = skb;
|
|
qh->head = skb;
|
|
}
|
|
qh->qlen++;
|
|
}
|
|
|
|
static int htb_enqueue(struct sk_buff *skb, struct Qdisc *sch,
|
|
struct sk_buff **to_free)
|
|
{
|
|
int uninitialized_var(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) {
|
|
htb_enqueue_tail(skb, sch, &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->un.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);
|
|
}
|
|
|
|
qdisc_qstats_backlog_inc(sch, skb);
|
|
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->un.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->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(hprio, 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;
|
|
|
|
qdisc_warn_nonwc("htb", cl->un.leaf.q);
|
|
htb_next_rb_node(level ? &cl->parent->un.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->un.leaf.deficit[level] -= qdisc_pkt_len(skb);
|
|
if (cl->un.leaf.deficit[level] < 0) {
|
|
cl->un.leaf.deficit[level] += cl->quantum;
|
|
htb_next_rb_node(level ? &cl->parent->un.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->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;
|
|
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;
|
|
}
|
|
}
|
|
qdisc_qstats_overlimit(sch);
|
|
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->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);
|
|
__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));
|
|
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 },
|
|
[TCA_HTB_DIRECT_QLEN] = { .type = NLA_U32 },
|
|
[TCA_HTB_RATE64] = { .type = NLA_U64 },
|
|
[TCA_HTB_CEIL64] = { .type = NLA_U64 },
|
|
};
|
|
|
|
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 int htb_init(struct Qdisc *sch, struct nlattr *opt)
|
|
{
|
|
struct htb_sched *q = qdisc_priv(sch);
|
|
struct nlattr *tb[TCA_HTB_MAX + 1];
|
|
struct tc_htb_glob *gopt;
|
|
int err;
|
|
int i;
|
|
|
|
if (!opt)
|
|
return -EINVAL;
|
|
|
|
err = nla_parse_nested(tb, TCA_HTB_MAX, opt, htb_policy);
|
|
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;
|
|
|
|
err = qdisc_class_hash_init(&q->clhash);
|
|
if (err < 0)
|
|
return err;
|
|
for (i = 0; i < TC_HTB_NUMPRIO; i++)
|
|
INIT_LIST_HEAD(q->drops + i);
|
|
|
|
qdisc_watchdog_init(&q->watchdog, sch);
|
|
INIT_WORK(&q->work, htb_work_func);
|
|
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;
|
|
|
|
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;
|
|
|
|
/* 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(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;
|
|
|
|
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 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->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));
|
|
|
|
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 ((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 int
|
|
htb_dump_class_stats(struct Qdisc *sch, unsigned long arg, struct gnet_dump *d)
|
|
{
|
|
struct htb_class *cl = (struct htb_class *)arg;
|
|
struct gnet_stats_queue qs = {
|
|
.drops = cl->drops,
|
|
};
|
|
__u32 qlen = 0;
|
|
|
|
if (!cl->level && cl->un.leaf.q) {
|
|
qlen = cl->un.leaf.q->q.qlen;
|
|
qs.backlog = cl->un.leaf.q->qstats.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 (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
|
|
d, NULL, &cl->bstats) < 0 ||
|
|
gnet_stats_copy_rate_est(d, NULL, &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 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->level)
|
|
return -EINVAL;
|
|
if (new == NULL &&
|
|
(new = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
|
|
cl->common.classid)) == NULL)
|
|
return -ENOBUFS;
|
|
|
|
*old = qdisc_replace(sch, new, &cl->un.leaf.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->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 > 1)
|
|
/* 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;
|
|
|
|
WARN_ON(cl->level || !cl->un.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->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->tokens = parent->buffer;
|
|
parent->ctokens = parent->cbuffer;
|
|
parent->t_c = ktime_get_ns();
|
|
parent->cmode = HTB_CAN_SEND;
|
|
}
|
|
|
|
static void htb_destroy_class(struct Qdisc *sch, struct htb_class *cl)
|
|
{
|
|
if (!cl->level) {
|
|
WARN_ON(!cl->un.leaf.q);
|
|
qdisc_destroy(cl->un.leaf.q);
|
|
}
|
|
gen_kill_estimator(&cl->bstats, &cl->rate_est);
|
|
tcf_destroy_chain(&cl->filter_list);
|
|
kfree(cl);
|
|
}
|
|
|
|
static void htb_destroy(struct Qdisc *sch)
|
|
{
|
|
struct htb_sched *q = qdisc_priv(sch);
|
|
struct hlist_node *next;
|
|
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_destroy_chain(&q->filter_list);
|
|
|
|
for (i = 0; i < q->clhash.hashsize; i++) {
|
|
hlist_for_each_entry(cl, &q->clhash.hash[i], common.hnode)
|
|
tcf_destroy_chain(&cl->filter_list);
|
|
}
|
|
for (i = 0; i < q->clhash.hashsize; i++) {
|
|
hlist_for_each_entry_safe(cl, next, &q->clhash.hash[i],
|
|
common.hnode)
|
|
htb_destroy_class(sch, cl);
|
|
}
|
|
qdisc_class_hash_destroy(&q->clhash);
|
|
__qdisc_reset_queue(&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;
|
|
struct Qdisc *new_q = NULL;
|
|
int last_child = 0;
|
|
|
|
/* 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)) {
|
|
new_q = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
|
|
cl->parent->common.classid);
|
|
last_child = 1;
|
|
}
|
|
|
|
sch_tree_lock(sch);
|
|
|
|
if (!cl->level) {
|
|
unsigned int qlen = cl->un.leaf.q->q.qlen;
|
|
unsigned int backlog = cl->un.leaf.q->qstats.backlog;
|
|
|
|
qdisc_reset(cl->un.leaf.q);
|
|
qdisc_tree_reduce_backlog(cl->un.leaf.q, qlen, backlog);
|
|
}
|
|
|
|
/* 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(q, cl, new_q);
|
|
|
|
BUG_ON(--cl->refcnt == 0);
|
|
/*
|
|
* This shouldn't happen: we "hold" one cops->get() when called
|
|
* from tc_ctl_tclass; the destroy method is done from cops->put().
|
|
*/
|
|
|
|
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 nlattr *tb[TCA_HTB_MAX + 1];
|
|
struct tc_htb_opt *hopt;
|
|
u64 rate64, ceil64;
|
|
|
|
/* extract all subattrs from opt attr */
|
|
if (!opt)
|
|
goto failure;
|
|
|
|
err = nla_parse_nested(tb, TCA_HTB_MAX, 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]);
|
|
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]));
|
|
|
|
if (hopt->ceil.linklayer == TC_LINKLAYER_UNAWARE)
|
|
qdisc_put_rtab(qdisc_get_rtab(&hopt->ceil, tb[TCA_HTB_CTAB]));
|
|
|
|
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) {
|
|
pr_err("htb: tree is too deep\n");
|
|
goto failure;
|
|
}
|
|
err = -ENOBUFS;
|
|
cl = kzalloc(sizeof(*cl), GFP_KERNEL);
|
|
if (!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) {
|
|
kfree(cl);
|
|
goto failure;
|
|
}
|
|
}
|
|
|
|
cl->refcnt = 1;
|
|
cl->children = 0;
|
|
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_queue,
|
|
&pfifo_qdisc_ops, classid);
|
|
sch_tree_lock(sch);
|
|
if (parent && !parent->level) {
|
|
unsigned int qlen = parent->un.leaf.q->q.qlen;
|
|
unsigned int backlog = parent->un.leaf.q->qstats.backlog;
|
|
|
|
/* turn parent into inner node */
|
|
qdisc_reset(parent->un.leaf.q);
|
|
qdisc_tree_reduce_backlog(parent->un.leaf.q, qlen, backlog);
|
|
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->hlevel[0].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->common.classid = classid;
|
|
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++;
|
|
} 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;
|
|
}
|
|
sch_tree_lock(sch);
|
|
}
|
|
|
|
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;
|
|
|
|
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->un.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) {
|
|
pr_warn("HTB: quantum of class %X is small. Consider r2q change.\n",
|
|
cl->common.classid);
|
|
cl->quantum = 1000;
|
|
}
|
|
if (!hopt->quantum && cl->quantum > 200000) {
|
|
pr_warn("HTB: quantum of class %X is big. Consider r2q change.\n",
|
|
cl->common.classid);
|
|
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_class_hash_grow(sch, &q->clhash);
|
|
|
|
*arg = (unsigned long)cl;
|
|
return 0;
|
|
|
|
failure:
|
|
return err;
|
|
}
|
|
|
|
static struct tcf_proto __rcu **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 __rcu **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_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 = {
|
|
.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 = {
|
|
.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,
|
|
.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");
|