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 */
  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
  52static inline psched_time_t psched_get_time(void)
  53{
  54        return PSCHED_NS2TICKS(ktime_to_ns(ktime_get()));
  55}
  56
  57static inline psched_tdiff_t
  58psched_tdiff_bounded(psched_time_t tv1, psched_time_t tv2, psched_time_t bound)
  59{
  60        return min(tv1 - tv2, bound);
  61}
  62
  63struct qdisc_watchdog {
  64        struct hrtimer  timer;
  65        struct Qdisc    *qdisc;
  66};
  67
  68extern void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc);
  69extern void qdisc_watchdog_schedule(struct qdisc_watchdog *wd,
  70                                    psched_time_t expires);
  71extern void qdisc_watchdog_cancel(struct qdisc_watchdog *wd);
  72
  73extern struct Qdisc_ops pfifo_qdisc_ops;
  74extern struct Qdisc_ops bfifo_qdisc_ops;
  75
  76extern int fifo_set_limit(struct Qdisc *q, unsigned int limit);
  77extern struct Qdisc *fifo_create_dflt(struct Qdisc *sch, struct Qdisc_ops *ops,
  78                                      unsigned int limit);
  79
  80extern int register_qdisc(struct Qdisc_ops *qops);
  81extern int unregister_qdisc(struct Qdisc_ops *qops);
  82extern void qdisc_list_del(struct Qdisc *q);
  83extern struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle);
  84extern struct Qdisc *qdisc_lookup_class(struct net_device *dev, u32 handle);
  85extern struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
  86                struct nlattr *tab);
  87extern void qdisc_put_rtab(struct qdisc_rate_table *tab);
  88extern void qdisc_put_stab(struct qdisc_size_table *tab);
  89extern void qdisc_warn_nonwc(char *txt, struct Qdisc *qdisc);
  90extern 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
  94extern void __qdisc_run(struct Qdisc *q);
  95
  96static 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
 102extern int tc_classify_compat(struct sk_buff *skb, struct tcf_proto *tp,
 103                              struct tcf_result *res);
 104extern 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 */
 110static inline unsigned psched_mtu(const struct net_device *dev)
 111{
 112        return dev->mtu + dev->hard_header_len;
 113}
 114
 115#endif
 116