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 by 1000 */
  45 #define PSCHED_US2NS(x)                 ((s64)(x) << 10)
  46 #define PSCHED_NS2US(x)                 ((x) >> 10)
  47
  48 #define PSCHED_TICKS_PER_SEC            PSCHED_NS2US(NSEC_PER_SEC)
  49 #define PSCHED_PASTPERFECT              0
  50
  51 static inline psched_time_t psched_get_time(void)
  52 {
  53         return PSCHED_NS2US(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
  75 extern int register_qdisc(struct Qdisc_ops *qops);
  76 extern int unregister_qdisc(struct Qdisc_ops *qops);
  77 extern struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle);
  78 extern struct Qdisc *qdisc_lookup_class(struct net_device *dev, u32 handle);
  79 extern struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
  80                 struct rtattr *tab);
  81 extern void qdisc_put_rtab(struct qdisc_rate_table *tab);
  82
  83 extern void __qdisc_run(struct net_device *dev);
  84
  85 static inline void qdisc_run(struct net_device *dev)
  86 {
  87         if (!netif_queue_stopped(dev) &&
  88             !test_and_set_bit(__LINK_STATE_QDISC_RUNNING, &dev->state))
  89                 __qdisc_run(dev);
  90 }
  91
  92 extern int tc_classify(struct sk_buff *skb, struct tcf_proto *tp,
  93         struct tcf_result *res);
  94
  95 /* Calculate maximal size of packet seen by hard_start_xmit
  96    routine of this device.
  97  */
  98 static inline unsigned psched_mtu(struct net_device *dev)
  99 {
 100         unsigned mtu = dev->mtu;
 101         return dev->hard_header ? mtu + dev->hard_header_len : mtu;
 102 }
 103
 104 #endif