xref: /linux/include/net/pkt_sched.h (revision d4b996f9ef1fe83d9ce9ad5c1ca0bd8231638ce5)
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 static inline void *qdisc_priv(struct Qdisc *q)
23 {
24 	return &q->privdata;
25 }
26 
27 static inline struct Qdisc *qdisc_from_priv(void *priv)
28 {
29 	return container_of(priv, struct Qdisc, privdata);
30 }
31 
32 /*
33    Timer resolution MUST BE < 10% of min_schedulable_packet_size/bandwidth
34 
35    Normal IP packet size ~ 512byte, hence:
36 
37    0.5Kbyte/1Mbyte/sec = 0.5msec, so that we need 50usec timer for
38    10Mbit ethernet.
39 
40    10msec resolution -> <50Kbit/sec.
41 
42    The result: [34]86 is not good choice for QoS router :-(
43 
44    The things are not so bad, because we may use artificial
45    clock evaluated by integration of network data flow
46    in the most critical places.
47  */
48 
49 typedef u64	psched_time_t;
50 typedef long	psched_tdiff_t;
51 
52 /* Avoid doing 64 bit divide */
53 #define PSCHED_SHIFT			6
54 #define PSCHED_TICKS2NS(x)		((s64)(x) << PSCHED_SHIFT)
55 #define PSCHED_NS2TICKS(x)		((x) >> PSCHED_SHIFT)
56 
57 #define PSCHED_TICKS_PER_SEC		PSCHED_NS2TICKS(NSEC_PER_SEC)
58 #define PSCHED_PASTPERFECT		0
59 
60 static inline psched_time_t psched_get_time(void)
61 {
62 	return PSCHED_NS2TICKS(ktime_get_ns());
63 }
64 
65 static inline psched_tdiff_t
66 psched_tdiff_bounded(psched_time_t tv1, psched_time_t tv2, psched_time_t bound)
67 {
68 	return min(tv1 - tv2, bound);
69 }
70 
71 struct qdisc_watchdog {
72 	u64		last_expires;
73 	struct hrtimer	timer;
74 	struct Qdisc	*qdisc;
75 };
76 
77 void qdisc_watchdog_init_clockid(struct qdisc_watchdog *wd, struct Qdisc *qdisc,
78 				 clockid_t clockid);
79 void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc);
80 
81 void qdisc_watchdog_schedule_range_ns(struct qdisc_watchdog *wd, u64 expires,
82 				      u64 delta_ns);
83 
84 static inline void qdisc_watchdog_schedule_ns(struct qdisc_watchdog *wd,
85 					      u64 expires)
86 {
87 	return qdisc_watchdog_schedule_range_ns(wd, expires, 0ULL);
88 }
89 
90 static inline void qdisc_watchdog_schedule(struct qdisc_watchdog *wd,
91 					   psched_time_t expires)
92 {
93 	qdisc_watchdog_schedule_ns(wd, PSCHED_TICKS2NS(expires));
94 }
95 
96 void qdisc_watchdog_cancel(struct qdisc_watchdog *wd);
97 
98 extern struct Qdisc_ops pfifo_qdisc_ops;
99 extern struct Qdisc_ops bfifo_qdisc_ops;
100 extern struct Qdisc_ops pfifo_head_drop_qdisc_ops;
101 
102 int fifo_set_limit(struct Qdisc *q, unsigned int limit);
103 struct Qdisc *fifo_create_dflt(struct Qdisc *sch, struct Qdisc_ops *ops,
104 			       unsigned int limit,
105 			       struct netlink_ext_ack *extack);
106 
107 int register_qdisc(struct Qdisc_ops *qops);
108 int unregister_qdisc(struct Qdisc_ops *qops);
109 void qdisc_get_default(char *id, size_t len);
110 int qdisc_set_default(const char *id);
111 
112 void qdisc_hash_add(struct Qdisc *q, bool invisible);
113 void qdisc_hash_del(struct Qdisc *q);
114 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle);
115 struct Qdisc *qdisc_lookup_rcu(struct net_device *dev, u32 handle);
116 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
117 					struct nlattr *tab,
118 					struct netlink_ext_ack *extack);
119 void qdisc_put_rtab(struct qdisc_rate_table *tab);
120 void qdisc_put_stab(struct qdisc_size_table *tab);
121 void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc);
122 bool sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
123 		     struct net_device *dev, struct netdev_queue *txq,
124 		     spinlock_t *root_lock, bool validate);
125 
126 void __qdisc_run(struct Qdisc *q);
127 
128 static inline void qdisc_run(struct Qdisc *q)
129 {
130 	if (qdisc_run_begin(q)) {
131 		__qdisc_run(q);
132 		qdisc_run_end(q);
133 	}
134 }
135 
136 /* Calculate maximal size of packet seen by hard_start_xmit
137    routine of this device.
138  */
139 static inline unsigned int psched_mtu(const struct net_device *dev)
140 {
141 	return dev->mtu + dev->hard_header_len;
142 }
143 
144 static inline struct net *qdisc_net(struct Qdisc *q)
145 {
146 	return dev_net(q->dev_queue->dev);
147 }
148 
149 struct tc_cbs_qopt_offload {
150 	u8 enable;
151 	s32 queue;
152 	s32 hicredit;
153 	s32 locredit;
154 	s32 idleslope;
155 	s32 sendslope;
156 };
157 
158 struct tc_etf_qopt_offload {
159 	u8 enable;
160 	s32 queue;
161 };
162 
163 struct tc_taprio_sched_entry {
164 	u8 command; /* TC_TAPRIO_CMD_* */
165 
166 	/* The gate_mask in the offloading side refers to traffic classes */
167 	u32 gate_mask;
168 	u32 interval;
169 };
170 
171 struct tc_taprio_qopt_offload {
172 	u8 enable;
173 	ktime_t base_time;
174 	u64 cycle_time;
175 	u64 cycle_time_extension;
176 
177 	size_t num_entries;
178 	struct tc_taprio_sched_entry entries[];
179 };
180 
181 /* Reference counting */
182 struct tc_taprio_qopt_offload *taprio_offload_get(struct tc_taprio_qopt_offload
183 						  *offload);
184 void taprio_offload_free(struct tc_taprio_qopt_offload *offload);
185 
186 /* Ensure skb_mstamp_ns, which might have been populated with the txtime, is
187  * not mistaken for a software timestamp, because this will otherwise prevent
188  * the dispatch of hardware timestamps to the socket.
189  */
190 static inline void skb_txtime_consumed(struct sk_buff *skb)
191 {
192 	skb->tstamp = ktime_set(0, 0);
193 }
194 
195 #endif
196