LXR linux/include/net/pkt

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef __NET_PKT_SCHED_H
   3#define __NET_PKT_SCHED_H
   4
   5#include <linux/jiffies.h>
   6#include <linux/ktime.h>
   7#include <linux/if_vlan.h>
   8#include <linux/netdevice.h>
   9#include <net/sch_generic.h>
  10#include <net/net_namespace.h>
  11#include <uapi/linux/pkt_sched.h>
  12
  13#define DEFAULT_TX_QUEUE_LEN    1000
  14
  15struct qdisc_walker {
  16        int     stop;
  17        int     skip;
  18        int     count;
  19        int     (*fn)(struct Qdisc *, unsigned long cl, struct qdisc_walker *);
  20};
  21
  22#define QDISC_ALIGNTO           64
  23#define QDISC_ALIGN(len)        (((len) + QDISC_ALIGNTO-1) & ~(QDISC_ALIGNTO-1))
  24
  25static inline void *qdisc_priv(struct Qdisc *q)
  26{
  27        return (char *) q + QDISC_ALIGN(sizeof(struct Qdisc));
  28}
  29
  30/* 
  31   Timer resolution MUST BE < 10% of min_schedulable_packet_size/bandwidth
  32   
  33   Normal IP packet size ~ 512byte, hence:
  34
  35   0.5Kbyte/1Mbyte/sec = 0.5msec, so that we need 50usec timer for
  36   10Mbit ethernet.
  37
  38   10msec resolution -> <50Kbit/sec.
  39   
  40   The result: [34]86 is not good choice for QoS router :-(
  41
  42   The things are not so bad, because we may use artificial
  43   clock evaluated by integration of network data flow
  44   in the most critical places.
  45 */
  46
  47typedef u64     psched_time_t;
  48typedef long    psched_tdiff_t;
  49
  50/* Avoid doing 64 bit divide */
  51#define PSCHED_SHIFT                    6
  52#define PSCHED_TICKS2NS(x)              ((s64)(x) << PSCHED_SHIFT)
  53#define PSCHED_NS2TICKS(x)              ((x) >> PSCHED_SHIFT)
  54
  55#define PSCHED_TICKS_PER_SEC            PSCHED_NS2TICKS(NSEC_PER_SEC)
  56#define PSCHED_PASTPERFECT              0
  57
  58static inline psched_time_t psched_get_time(void)
  59{
  60        return PSCHED_NS2TICKS(ktime_get_ns());
  61}
  62
  63static inline psched_tdiff_t
  64psched_tdiff_bounded(psched_time_t tv1, psched_time_t tv2, psched_time_t bound)
  65{
  66        return min(tv1 - tv2, bound);
  67}
  68
  69struct qdisc_watchdog {
  70        u64             last_expires;
  71        struct hrtimer  timer;
  72        struct Qdisc    *qdisc;
  73};
  74
  75void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc);
  76void qdisc_watchdog_schedule_ns(struct qdisc_watchdog *wd, u64 expires);
  77
  78static inline void qdisc_watchdog_schedule(struct qdisc_watchdog *wd,
  79                                           psched_time_t expires)
  80{
  81        qdisc_watchdog_schedule_ns(wd, PSCHED_TICKS2NS(expires));
  82}
  83
  84void qdisc_watchdog_cancel(struct qdisc_watchdog *wd);
  85
  86extern struct Qdisc_ops pfifo_qdisc_ops;
  87extern struct Qdisc_ops bfifo_qdisc_ops;
  88extern struct Qdisc_ops pfifo_head_drop_qdisc_ops;
  89
  90int fifo_set_limit(struct Qdisc *q, unsigned int limit);
  91struct Qdisc *fifo_create_dflt(struct Qdisc *sch, struct Qdisc_ops *ops,
  92                               unsigned int limit,
  93                               struct netlink_ext_ack *extack);
  94
  95int register_qdisc(struct Qdisc_ops *qops);
  96int unregister_qdisc(struct Qdisc_ops *qops);
  97void qdisc_get_default(char *id, size_t len);
  98int qdisc_set_default(const char *id);
  99
 100void qdisc_hash_add(struct Qdisc *q, bool invisible);
 101void qdisc_hash_del(struct Qdisc *q);
 102struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle);
 103struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
 104                                        struct nlattr *tab,
 105                                        struct netlink_ext_ack *extack);
 106void qdisc_put_rtab(struct qdisc_rate_table *tab);
 107void qdisc_put_stab(struct qdisc_size_table *tab);
 108void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc);
 109bool sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
 110                     struct net_device *dev, struct netdev_queue *txq,
 111                     spinlock_t *root_lock, bool validate);
 112
 113void __qdisc_run(struct Qdisc *q);
 114
 115static inline void qdisc_run(struct Qdisc *q)
 116{
 117        if (qdisc_run_begin(q)) {
 118                __qdisc_run(q);
 119                qdisc_run_end(q);
 120        }
 121}
 122
 123static inline __be16 tc_skb_protocol(const struct sk_buff *skb)
 124{
 125        /* We need to take extra care in case the skb came via
 126         * vlan accelerated path. In that case, use skb->vlan_proto
 127         * as the original vlan header was already stripped.
 128         */
 129        if (skb_vlan_tag_present(skb))
 130                return skb->vlan_proto;
 131        return skb->protocol;
 132}
 133
 134/* Calculate maximal size of packet seen by hard_start_xmit
 135   routine of this device.
 136 */
 137static inline unsigned int psched_mtu(const struct net_device *dev)
 138{
 139        return dev->mtu + dev->hard_header_len;
 140}
 141
 142static inline struct net *qdisc_net(struct Qdisc *q)
 143{
 144        return dev_net(q->dev_queue->dev);
 145}
 146
 147struct tc_cbs_qopt_offload {
 148        u8 enable;
 149        s32 queue;
 150        s32 hicredit;
 151        s32 locredit;
 152        s32 idleslope;
 153        s32 sendslope;
 154};
 155
 156#endif
 157