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