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 <net/sch_generic.h>
   7
   8 struct qdisc_walker
   9 {
  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           32
  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 artifical
  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_to_ns(ktime_get()));
  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 extern void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc);
  69 extern void qdisc_watchdog_schedule(struct qdisc_watchdog *wd,
  70                                     psched_time_t expires);
  71 extern void qdisc_watchdog_cancel(struct qdisc_watchdog *wd);
  72
  73 extern struct Qdisc_ops pfifo_qdisc_ops;
  74 extern struct Qdisc_ops bfifo_qdisc_ops;
  75
  76 extern int fifo_set_limit(struct Qdisc *q, unsigned int limit);
  77 extern struct Qdisc *fifo_create_dflt(struct Qdisc *sch, struct Qdisc_ops *ops,
  78                                       unsigned int limit);
  79
  80 extern int register_qdisc(struct Qdisc_ops *qops);
  81 extern int unregister_qdisc(struct Qdisc_ops *qops);
  82 extern void qdisc_list_del(struct Qdisc *q);
  83 extern struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle);
  84 extern struct Qdisc *qdisc_lookup_class(struct net_device *dev, u32 handle);
  85 extern struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
  86                 struct nlattr *tab);
  87 extern void qdisc_put_rtab(struct qdisc_rate_table *tab);
  88 extern void qdisc_put_stab(struct qdisc_size_table *tab);
  89 extern void qdisc_warn_nonwc(char *txt, struct Qdisc *qdisc);
  90 extern int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
  91                            struct net_device *dev, struct netdev_queue *txq,
  92                            spinlock_t *root_lock);
  93
  94 extern void __qdisc_run(struct Qdisc *q);
  95
  96 static inline void qdisc_run(struct Qdisc *q)
  97 {
  98         if (!test_and_set_bit(__QDISC_STATE_RUNNING, &q->state))
  99                 __qdisc_run(q);
 100 }
 101
 102 extern int tc_classify_compat(struct sk_buff *skb, struct tcf_proto *tp,
 103                               struct tcf_result *res);
 104 extern int tc_classify(struct sk_buff *skb, struct tcf_proto *tp,
 105                        struct tcf_result *res);
 106
 107 /* Calculate maximal size of packet seen by hard_start_xmit
 108    routine of this device.
 109  */
 110 static inline unsigned psched_mtu(const struct net_device *dev)
 111 {
 112         return dev->mtu + dev->hard_header_len;
 113 }
 114
 115 #endif