include/net/pkt_sched.h

   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
  15 struct 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
  25 static 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
  47 typedef u64     psched_time_t;
  48 typedef 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
  58 static inline psched_time_t psched_get_time(void)
  59 {
  60         return PSCHED_NS2TICKS(ktime_get_ns());
  61 }
  62
  63 static inline psched_tdiff_t
  64 psched_tdiff_bounded(psched_time_t tv1, psched_time_t tv2, psched_time_t bound)
  65 {
  66         return min(tv1 - tv2, bound);
  67 }
  68
  69 struct qdisc_watchdog {
  70         u64             last_expires;
  71         struct hrtimer  timer;
  72         struct Qdisc    *qdisc;
  73 };
  74
  75 void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc);
  76 void qdisc_watchdog_schedule_ns(struct qdisc_watchdog *wd, u64 expires);
  77
  78 static 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
  84 void qdisc_watchdog_cancel(struct qdisc_watchdog *wd);
  85
  86 extern struct Qdisc_ops pfifo_qdisc_ops;
  87 extern struct Qdisc_ops bfifo_qdisc_ops;
  88 extern struct Qdisc_ops pfifo_head_drop_qdisc_ops;
  89
  90 int fifo_set_limit(struct Qdisc *q, unsigned int limit);
  91 struct Qdisc *fifo_create_dflt(struct Qdisc *sch, struct Qdisc_ops *ops,
  92                                unsigned int limit);
  93
  94 int register_qdisc(struct Qdisc_ops *qops);
  95 int unregister_qdisc(struct Qdisc_ops *qops);
  96 void qdisc_get_default(char *id, size_t len);
  97 int qdisc_set_default(const char *id);
  98
  99 void qdisc_hash_add(struct Qdisc *q, bool invisible);
 100 void qdisc_hash_del(struct Qdisc *q);
 101 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle);
 102 struct Qdisc *qdisc_lookup_class(struct net_device *dev, u32 handle);
 103 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
 104                                         struct nlattr *tab);
 105 void qdisc_put_rtab(struct qdisc_rate_table *tab);
 106 void qdisc_put_stab(struct qdisc_size_table *tab);
 107 void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc);
 108 int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
 109                     struct net_device *dev, struct netdev_queue *txq,
 110                     spinlock_t *root_lock, bool validate);
 111
 112 void __qdisc_run(struct Qdisc *q);
 113
 114 static inline void qdisc_run(struct Qdisc *q)
 115 {
 116         if (qdisc_run_begin(q))
 117                 __qdisc_run(q);
 118 }
 119
 120 static inline __be16 tc_skb_protocol(const struct sk_buff *skb)
 121 {
 122         /* We need to take extra care in case the skb came via
 123          * vlan accelerated path. In that case, use skb->vlan_proto
 124          * as the original vlan header was already stripped.
 125          */
 126         if (skb_vlan_tag_present(skb))
 127                 return skb->vlan_proto;
 128         return skb->protocol;
 129 }
 130
 131 /* Calculate maximal size of packet seen by hard_start_xmit
 132    routine of this device.
 133  */
 134 static inline unsigned int psched_mtu(const struct net_device *dev)
 135 {
 136         return dev->mtu + dev->hard_header_len;
 137 }
 138
 139 static inline struct net *qdisc_net(struct Qdisc *q)
 140 {
 141         return dev_net(q->dev_queue->dev);
 142 }
 143
 144 struct tc_cbs_qopt_offload {
 145         u8 enable;
 146         s32 queue;
 147         s32 hicredit;
 148         s32 locredit;
 149         s32 idleslope;
 150         s32 sendslope;
 151 };
 152
 153 #endif