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         struct hrtimer  timer;
  65         struct Qdisc    *qdisc;
  66 };
  67
  68 void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc);
  69 void qdisc_watchdog_schedule_ns(struct qdisc_watchdog *wd, u64 expires, bool throttle);
  70
  71 static inline void qdisc_watchdog_schedule(struct qdisc_watchdog *wd,
  72                                            psched_time_t expires)
  73 {
  74         qdisc_watchdog_schedule_ns(wd, PSCHED_TICKS2NS(expires), true);
  75 }
  76
  77 void qdisc_watchdog_cancel(struct qdisc_watchdog *wd);
  78
  79 extern struct Qdisc_ops pfifo_qdisc_ops;
  80 extern struct Qdisc_ops bfifo_qdisc_ops;
  81 extern struct Qdisc_ops pfifo_head_drop_qdisc_ops;
  82
  83 int fifo_set_limit(struct Qdisc *q, unsigned int limit);
  84 struct Qdisc *fifo_create_dflt(struct Qdisc *sch, struct Qdisc_ops *ops,
  85                                unsigned int limit);
  86
  87 int register_qdisc(struct Qdisc_ops *qops);
  88 int unregister_qdisc(struct Qdisc_ops *qops);
  89 void qdisc_get_default(char *id, size_t len);
  90 int qdisc_set_default(const char *id);
  91
  92 void qdisc_list_add(struct Qdisc *q);
  93 void qdisc_list_del(struct Qdisc *q);
  94 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle);
  95 struct Qdisc *qdisc_lookup_class(struct net_device *dev, u32 handle);
  96 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
  97                                         struct nlattr *tab);
  98 void qdisc_put_rtab(struct qdisc_rate_table *tab);
  99 void qdisc_put_stab(struct qdisc_size_table *tab);
 100 void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc);
 101 int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
 102                     struct net_device *dev, struct netdev_queue *txq,
 103                     spinlock_t *root_lock, bool validate);
 104
 105 void __qdisc_run(struct Qdisc *q);
 106
 107 static inline void qdisc_run(struct Qdisc *q)
 108 {
 109         if (qdisc_run_begin(q))
 110                 __qdisc_run(q);
 111 }
 112
 113 int tc_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 114                 struct tcf_result *res, bool compat_mode);
 115
 116 static inline __be16 tc_skb_protocol(const struct sk_buff *skb)
 117 {
 118         /* We need to take extra care in case the skb came via
 119          * vlan accelerated path. In that case, use skb->vlan_proto
 120          * as the original vlan header was already stripped.
 121          */
 122         if (skb_vlan_tag_present(skb))
 123                 return skb->vlan_proto;
 124         return skb->protocol;
 125 }
 126
 127 /* Calculate maximal size of packet seen by hard_start_xmit
 128    routine of this device.
 129  */
 130 static inline unsigned int psched_mtu(const struct net_device *dev)
 131 {
 132         return dev->mtu + dev->hard_header_len;
 133 }
 134
 135 #endif