root/include/net/pkt_sched.h

INCLUDED FROM

DEFINITIONS

1. qdisc_priv
2. psched_get_time
3. psched_tdiff_bounded
4. qdisc_watchdog_schedule
5. qdisc_run
6. tc_skb_protocol
7. psched_mtu
8. qdisc_net

   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_clockid(struct qdisc_watchdog *wd, struct Qdisc *qdisc,
  76                                  clockid_t clockid);
  77 void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc);
  78 void qdisc_watchdog_schedule_ns(struct qdisc_watchdog *wd, u64 expires);
  79 
  80 static inline void qdisc_watchdog_schedule(struct qdisc_watchdog *wd,
  81                                            psched_time_t expires)
  82 {
  83         qdisc_watchdog_schedule_ns(wd, PSCHED_TICKS2NS(expires));
  84 }
  85 
  86 void qdisc_watchdog_cancel(struct qdisc_watchdog *wd);
  87 
  88 extern struct Qdisc_ops pfifo_qdisc_ops;
  89 extern struct Qdisc_ops bfifo_qdisc_ops;
  90 extern struct Qdisc_ops pfifo_head_drop_qdisc_ops;
  91 
  92 int fifo_set_limit(struct Qdisc *q, unsigned int limit);
  93 struct Qdisc *fifo_create_dflt(struct Qdisc *sch, struct Qdisc_ops *ops,
  94                                unsigned int limit,
  95                                struct netlink_ext_ack *extack);
  96 
  97 int register_qdisc(struct Qdisc_ops *qops);
  98 int unregister_qdisc(struct Qdisc_ops *qops);
  99 void qdisc_get_default(char *id, size_t len);
 100 int qdisc_set_default(const char *id);
 101 
 102 void qdisc_hash_add(struct Qdisc *q, bool invisible);
 103 void qdisc_hash_del(struct Qdisc *q);
 104 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle);
 105 struct Qdisc *qdisc_lookup_rcu(struct net_device *dev, u32 handle);
 106 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
 107                                         struct nlattr *tab,
 108                                         struct netlink_ext_ack *extack);
 109 void qdisc_put_rtab(struct qdisc_rate_table *tab);
 110 void qdisc_put_stab(struct qdisc_size_table *tab);
 111 void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc);
 112 bool sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
 113                      struct net_device *dev, struct netdev_queue *txq,
 114                      spinlock_t *root_lock, bool validate);
 115 
 116 void __qdisc_run(struct Qdisc *q);
 117 
 118 static inline void qdisc_run(struct Qdisc *q)
 119 {
 120         if (qdisc_run_begin(q)) {
 121                 /* NOLOCK qdisc must check 'state' under the qdisc seqlock
 122                  * to avoid racing with dev_qdisc_reset()
 123                  */
 124                 if (!(q->flags & TCQ_F_NOLOCK) ||
 125                     likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
 126                         __qdisc_run(q);
 127                 qdisc_run_end(q);
 128         }
 129 }
 130 
 131 static inline __be16 tc_skb_protocol(const struct sk_buff *skb)
 132 {
 133         /* We need to take extra care in case the skb came via
 134          * vlan accelerated path. In that case, use skb->vlan_proto
 135          * as the original vlan header was already stripped.
 136          */
 137         if (skb_vlan_tag_present(skb))
 138                 return skb->vlan_proto;
 139         return skb->protocol;
 140 }
 141 
 142 /* Calculate maximal size of packet seen by hard_start_xmit
 143    routine of this device.
 144  */
 145 static inline unsigned int psched_mtu(const struct net_device *dev)
 146 {
 147         return dev->mtu + dev->hard_header_len;
 148 }
 149 
 150 static inline struct net *qdisc_net(struct Qdisc *q)
 151 {
 152         return dev_net(q->dev_queue->dev);
 153 }
 154 
 155 struct tc_cbs_qopt_offload {
 156         u8 enable;
 157         s32 queue;
 158         s32 hicredit;
 159         s32 locredit;
 160         s32 idleslope;
 161         s32 sendslope;
 162 };
 163 
 164 struct tc_etf_qopt_offload {
 165         u8 enable;
 166         s32 queue;
 167 };
 168 
 169 struct tc_taprio_sched_entry {
 170         u8 command; /* TC_TAPRIO_CMD_* */
 171 
 172         /* The gate_mask in the offloading side refers to traffic classes */
 173         u32 gate_mask;
 174         u32 interval;
 175 };
 176 
 177 struct tc_taprio_qopt_offload {
 178         u8 enable;
 179         ktime_t base_time;
 180         u64 cycle_time;
 181         u64 cycle_time_extension;
 182 
 183         size_t num_entries;
 184         struct tc_taprio_sched_entry entries[0];
 185 };
 186 
 187 /* Reference counting */
 188 struct tc_taprio_qopt_offload *taprio_offload_get(struct tc_taprio_qopt_offload
 189                                                   *offload);
 190 void taprio_offload_free(struct tc_taprio_qopt_offload *offload);
 191 
 192 #endif