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         int     stop;
  10         int     skip;
  11         int     count;
  12         int     (*fn)(struct Qdisc *, unsigned long cl, struct qdisc_walker *);
  13 };
  14
  15 #define QDISC_ALIGNTO           64
  16 #define QDISC_ALIGN(len)        (((len) + QDISC_ALIGNTO-1) & ~(QDISC_ALIGNTO-1))
  17
  18 static inline void *qdisc_priv(struct Qdisc *q)
  19 {
  20         return (char *) q + QDISC_ALIGN(sizeof(struct Qdisc));
  21 }
  22
  23 /*
  24    Timer resolution MUST BE < 10% of min_schedulable_packet_size/bandwidth
  25
  26    Normal IP packet size ~ 512byte, hence:
  27
  28    0.5Kbyte/1Mbyte/sec = 0.5msec, so that we need 50usec timer for
  29    10Mbit ethernet.
  30
  31    10msec resolution -> <50Kbit/sec.
  32
  33    The result: [34]86 is not good choice for QoS router :-(
  34
  35    The things are not so bad, because we may use artifical
  36    clock evaluated by integration of network data flow
  37    in the most critical places.
  38  */
  39
  40 typedef u64     psched_time_t;
  41 typedef long    psched_tdiff_t;
  42
  43 /* Avoid doing 64 bit divide */
  44 #define PSCHED_SHIFT                    6
  45 #define PSCHED_TICKS2NS(x)              ((s64)(x) << PSCHED_SHIFT)
  46 #define PSCHED_NS2TICKS(x)              ((x) >> PSCHED_SHIFT)
  47
  48 #define PSCHED_TICKS_PER_SEC            PSCHED_NS2TICKS(NSEC_PER_SEC)
  49 #define PSCHED_PASTPERFECT              0
  50
  51 static inline psched_time_t psched_get_time(void)
  52 {
  53         return PSCHED_NS2TICKS(ktime_to_ns(ktime_get()));
  54 }
  55
  56 static inline psched_tdiff_t
  57 psched_tdiff_bounded(psched_time_t tv1, psched_time_t tv2, psched_time_t bound)
  58 {
  59         return min(tv1 - tv2, bound);
  60 }
  61
  62 struct qdisc_watchdog {
  63         struct hrtimer  timer;
  64         struct Qdisc    *qdisc;
  65 };
  66
  67 extern void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc);
  68 extern void qdisc_watchdog_schedule(struct qdisc_watchdog *wd,
  69                                     psched_time_t expires);
  70 extern void qdisc_watchdog_cancel(struct qdisc_watchdog *wd);
  71
  72 extern struct Qdisc_ops pfifo_qdisc_ops;
  73 extern struct Qdisc_ops bfifo_qdisc_ops;
  74 extern struct Qdisc_ops pfifo_head_drop_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 (qdisc_run_begin(q))
  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