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        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
  18static 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 artificial
  36   clock evaluated by integration of network data flow
  37   in the most critical places.
  38 */
  39
  40typedef u64     psched_time_t;
  41typedef 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
  51static inline psched_time_t psched_get_time(void)
  52{
  53        return PSCHED_NS2TICKS(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
  67void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc);
  68void qdisc_watchdog_schedule_ns(struct qdisc_watchdog *wd, u64 expires);
  69
  70static inline void qdisc_watchdog_schedule(struct qdisc_watchdog *wd,
  71                                           psched_time_t expires)
  72{
  73        qdisc_watchdog_schedule_ns(wd, PSCHED_TICKS2NS(expires));
  74}
  75
  76void qdisc_watchdog_cancel(struct qdisc_watchdog *wd);
  77
  78extern struct Qdisc_ops pfifo_qdisc_ops;
  79extern struct Qdisc_ops bfifo_qdisc_ops;
  80extern struct Qdisc_ops pfifo_head_drop_qdisc_ops;
  81
  82int fifo_set_limit(struct Qdisc *q, unsigned int limit);
  83struct Qdisc *fifo_create_dflt(struct Qdisc *sch, struct Qdisc_ops *ops,
  84                               unsigned int limit);
  85
  86int register_qdisc(struct Qdisc_ops *qops);
  87int unregister_qdisc(struct Qdisc_ops *qops);
  88void qdisc_get_default(char *id, size_t len);
  89int qdisc_set_default(const char *id);
  90
  91void qdisc_list_del(struct Qdisc *q);
  92struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle);
  93struct Qdisc *qdisc_lookup_class(struct net_device *dev, u32 handle);
  94struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
  95                                        struct nlattr *tab);
  96void qdisc_put_rtab(struct qdisc_rate_table *tab);
  97void qdisc_put_stab(struct qdisc_size_table *tab);
  98void qdisc_warn_nonwc(char *txt, struct Qdisc *qdisc);
  99int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
 100                    struct net_device *dev, struct netdev_queue *txq,
 101                    spinlock_t *root_lock);
 102
 103void __qdisc_run(struct Qdisc *q);
 104
 105static inline void qdisc_run(struct Qdisc *q)
 106{
 107        if (qdisc_run_begin(q))
 108                __qdisc_run(q);
 109}
 110
 111int tc_classify_compat(struct sk_buff *skb, const struct tcf_proto *tp,
 112                       struct tcf_result *res);
 113int tc_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 114                struct tcf_result *res);
 115
 116/* Calculate maximal size of packet seen by hard_start_xmit
 117   routine of this device.
 118 */
 119static inline unsigned int psched_mtu(const struct net_device *dev)
 120{
 121        return dev->mtu + dev->hard_header_len;
 122}
 123
 124#endif
 125