include/net/pkt_sched.h

   1 #ifndef __NET_PKT_SCHED_H
   2 #define __NET_PKT_SCHED_H
   3
   4 #include <linux/jiffies.h>
   5 #include <linux/ktime.h>
   6 #include <linux/if_vlan.h>
   7 #include <net/sch_generic.h>
   8
   9 struct qdisc_walker {
  10         int     stop;
  11         int     skip;
  12         int     count;
  13         int     (*fn)(struct Qdisc *, unsigned long cl, struct qdisc_walker *);
  14 };
  15
  16 #define QDISC_ALIGNTO           64
  17 #define QDISC_ALIGN(len)        (((len) + QDISC_ALIGNTO-1) & ~(QDISC_ALIGNTO-1))
  18
  19 static inline void *qdisc_priv(struct Qdisc *q)
  20 {
  21         return (char *) q + QDISC_ALIGN(sizeof(struct Qdisc));
  22 }
  23
  24 /*
  25    Timer resolution MUST BE < 10% of min_schedulable_packet_size/bandwidth
  26
  27    Normal IP packet size ~ 512byte, hence:
  28
  29    0.5Kbyte/1Mbyte/sec = 0.5msec, so that we need 50usec timer for
  30    10Mbit ethernet.
  31
  32    10msec resolution -> <50Kbit/sec.
  33
  34    The result: [34]86 is not good choice for QoS router :-(
  35
  36    The things are not so bad, because we may use artificial
  37    clock evaluated by integration of network data flow
  38    in the most critical places.
  39  */
  40
  41 typedef u64     psched_time_t;
  42 typedef long    psched_tdiff_t;
  43
  44 /* Avoid doing 64 bit divide */
  45 #define PSCHED_SHIFT                    6
  46 #define PSCHED_TICKS2NS(x)              ((s64)(x) << PSCHED_SHIFT)
  47 #define PSCHED_NS2TICKS(x)              ((x) >> PSCHED_SHIFT)
  48
  49 #define PSCHED_TICKS_PER_SEC            PSCHED_NS2TICKS(NSEC_PER_SEC)
  50 #define PSCHED_PASTPERFECT              0
  51
  52 static inline psched_time_t psched_get_time(void)
  53 {
  54         return PSCHED_NS2TICKS(ktime_get_ns());
  55 }
  56
  57 static inline psched_tdiff_t
  58 psched_tdiff_bounded(psched_time_t tv1, psched_time_t tv2, psched_time_t bound)
  59 {
  60         return min(tv1 - tv2, bound);
  61 }
  62
  63 struct qdisc_watchdog {
  64         u64             last_expires;
  65         struct hrtimer  timer;
  66         struct Qdisc    *qdisc;
  67 };
  68
  69 void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc);
  70 void qdisc_watchdog_schedule_ns(struct qdisc_watchdog *wd, u64 expires);
  71
  72 static inline void qdisc_watchdog_schedule(struct qdisc_watchdog *wd,
  73                                            psched_time_t expires)
  74 {
  75         qdisc_watchdog_schedule_ns(wd, PSCHED_TICKS2NS(expires));
  76 }
  77
  78 void qdisc_watchdog_cancel(struct qdisc_watchdog *wd);
  79
  80 extern struct Qdisc_ops pfifo_qdisc_ops;
  81 extern struct Qdisc_ops bfifo_qdisc_ops;
  82 extern struct Qdisc_ops pfifo_head_drop_qdisc_ops;
  83
  84 int fifo_set_limit(struct Qdisc *q, unsigned int limit);
  85 struct Qdisc *fifo_create_dflt(struct Qdisc *sch, struct Qdisc_ops *ops,
  86                                unsigned int limit);
  87
  88 int register_qdisc(struct Qdisc_ops *qops);
  89 int unregister_qdisc(struct Qdisc_ops *qops);
  90 void qdisc_get_default(char *id, size_t len);
  91 int qdisc_set_default(const char *id);
  92
  93 void qdisc_list_add(struct Qdisc *q);
  94 void qdisc_list_del(struct Qdisc *q);
  95 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle);
  96 struct Qdisc *qdisc_lookup_class(struct net_device *dev, u32 handle);
  97 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
  98                                         struct nlattr *tab);
  99 void qdisc_put_rtab(struct qdisc_rate_table *tab);
 100 void qdisc_put_stab(struct qdisc_size_table *tab);
 101 void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc);
 102 int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
 103                     struct net_device *dev, struct netdev_queue *txq,
 104                     spinlock_t *root_lock, bool validate);
 105
 106 void __qdisc_run(struct Qdisc *q);
 107
 108 static inline void qdisc_run(struct Qdisc *q)
 109 {
 110         if (qdisc_run_begin(q))
 111                 __qdisc_run(q);
 112 }
 113
 114 int tc_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 115                 struct tcf_result *res, bool compat_mode);
 116
 117 static inline __be16 tc_skb_protocol(const struct sk_buff *skb)
 118 {
 119         /* We need to take extra care in case the skb came via
 120          * vlan accelerated path. In that case, use skb->vlan_proto
 121          * as the original vlan header was already stripped.
 122          */
 123         if (skb_vlan_tag_present(skb))
 124                 return skb->vlan_proto;
 125         return skb->protocol;
 126 }
 127
 128 /* Calculate maximal size of packet seen by hard_start_xmit
 129    routine of this device.
 130  */
 131 static inline unsigned int psched_mtu(const struct net_device *dev)
 132 {
 133         return dev->mtu + dev->hard_header_len;
 134 }
 135
 136 #endif