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 extern rwlock_t qdisc_tree_lock;
  17
  18 #define QDISC_ALIGNTO           32
  19 #define QDISC_ALIGN(len)        (((len) + QDISC_ALIGNTO-1) & ~(QDISC_ALIGNTO-1))
  20
  21 static inline void *qdisc_priv(struct Qdisc *q)
  22 {
  23         return (char *) q + QDISC_ALIGN(sizeof(struct Qdisc));
  24 }
  25
  26 /*
  27    Timer resolution MUST BE < 10% of min_schedulable_packet_size/bandwidth
  28
  29    Normal IP packet size ~ 512byte, hence:
  30
  31    0.5Kbyte/1Mbyte/sec = 0.5msec, so that we need 50usec timer for
  32    10Mbit ethernet.
  33
  34    10msec resolution -> <50Kbit/sec.
  35
  36    The result: [34]86 is not good choice for QoS router :-(
  37
  38    The things are not so bad, because we may use artifical
  39    clock evaluated by integration of network data flow
  40    in the most critical places.
  41  */
  42
  43 typedef u64     psched_time_t;
  44 typedef long    psched_tdiff_t;
  45
  46 /* Avoid doing 64 bit divide by 1000 */
  47 #define PSCHED_US2NS(x)                 ((s64)(x) << 10)
  48 #define PSCHED_NS2US(x)                 ((x) >> 10)
  49
  50 #define PSCHED_TICKS_PER_SEC            PSCHED_NS2US(NSEC_PER_SEC)
  51 #define PSCHED_GET_TIME(stamp) \
  52         ((stamp) = PSCHED_NS2US(ktime_to_ns(ktime_get())))
  53
  54 #define PSCHED_TDIFF_SAFE(tv1, tv2, bound) \
  55                                         min_t(long long, (tv1) - (tv2), bound)
  56 #define PSCHED_PASTPERFECT              0
  57
  58 struct qdisc_watchdog {
  59         struct hrtimer  timer;
  60         struct Qdisc    *qdisc;
  61 };
  62
  63 extern void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc);
  64 extern void qdisc_watchdog_schedule(struct qdisc_watchdog *wd,
  65                                     psched_time_t expires);
  66 extern void qdisc_watchdog_cancel(struct qdisc_watchdog *wd);
  67
  68 extern struct Qdisc_ops pfifo_qdisc_ops;
  69 extern struct Qdisc_ops bfifo_qdisc_ops;
  70
  71 extern int register_qdisc(struct Qdisc_ops *qops);
  72 extern int unregister_qdisc(struct Qdisc_ops *qops);
  73 extern struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle);
  74 extern struct Qdisc *qdisc_lookup_class(struct net_device *dev, u32 handle);
  75 extern struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
  76                 struct rtattr *tab);
  77 extern void qdisc_put_rtab(struct qdisc_rate_table *tab);
  78
  79 extern void __qdisc_run(struct net_device *dev);
  80
  81 static inline void qdisc_run(struct net_device *dev)
  82 {
  83         if (!netif_queue_stopped(dev) &&
  84             !test_and_set_bit(__LINK_STATE_QDISC_RUNNING, &dev->state))
  85                 __qdisc_run(dev);
  86 }
  87
  88 extern int tc_classify(struct sk_buff *skb, struct tcf_proto *tp,
  89         struct tcf_result *res);
  90
  91 /* Calculate maximal size of packet seen by hard_start_xmit
  92    routine of this device.
  93  */
  94 static inline unsigned psched_mtu(struct net_device *dev)
  95 {
  96         unsigned mtu = dev->mtu;
  97         return dev->hard_header ? mtu + dev->hard_header_len : mtu;
  98 }
  99
 100 #endif