LXR linux/include/net/pkt

   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
   8struct 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
  19static 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
  41typedef u64     psched_time_t;
  42typedef 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
  51static inline psched_time_t psched_get_time(void)
  52{
  53        return PSCHED_NS2US(ktime_to_ns(ktime_get()));
  54}
  55
  56static inline psched_tdiff_t
  57psched_tdiff_bounded(psched_time_t tv1, psched_time_t tv2, psched_time_t bound)
  58{
  59        return min(tv1 - tv2, bound);
  60}
  61
  62struct qdisc_watchdog {
  63        struct hrtimer  timer;
  64        struct Qdisc    *qdisc;
  65};
  66
  67extern void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc);
  68extern void qdisc_watchdog_schedule(struct qdisc_watchdog *wd,
  69                                    psched_time_t expires);
  70extern void qdisc_watchdog_cancel(struct qdisc_watchdog *wd);
  71
  72extern struct Qdisc_ops pfifo_qdisc_ops;
  73extern struct Qdisc_ops bfifo_qdisc_ops;
  74
  75extern int fifo_set_limit(struct Qdisc *q, unsigned int limit);
  76extern struct Qdisc *fifo_create_dflt(struct Qdisc *sch, struct Qdisc_ops *ops,
  77                                      unsigned int limit);
  78
  79extern int register_qdisc(struct Qdisc_ops *qops);
  80extern int unregister_qdisc(struct Qdisc_ops *qops);
  81extern void qdisc_list_del(struct Qdisc *q);
  82extern struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle);
  83extern struct Qdisc *qdisc_lookup_class(struct net_device *dev, u32 handle);
  84extern struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
  85                struct nlattr *tab);
  86extern void qdisc_put_rtab(struct qdisc_rate_table *tab);
  87extern void qdisc_put_stab(struct qdisc_size_table *tab);
  88extern void qdisc_warn_nonwc(char *txt, struct Qdisc *qdisc);
  89
  90extern void __qdisc_run(struct Qdisc *q);
  91
  92static inline void qdisc_run(struct Qdisc *q)
  93{
  94        if (!test_and_set_bit(__QDISC_STATE_RUNNING, &q->state))
  95                __qdisc_run(q);
  96}
  97
  98extern int tc_classify_compat(struct sk_buff *skb, struct tcf_proto *tp,
  99                              struct tcf_result *res);
 100extern int tc_classify(struct sk_buff *skb, struct tcf_proto *tp,
 101                       struct tcf_result *res);
 102
 103/* Calculate maximal size of packet seen by hard_start_xmit
 104   routine of this device.
 105 */
 106static inline unsigned psched_mtu(const struct net_device *dev)
 107{
 108        return dev->mtu + dev->hard_header_len;
 109}
 110
 111#endif
 112