xref: /openbmc/linux/include/net/pkt_sched.h (revision 4cff79e9)
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 			       struct netlink_ext_ack *extack);
94 
95 int register_qdisc(struct Qdisc_ops *qops);
96 int unregister_qdisc(struct Qdisc_ops *qops);
97 void qdisc_get_default(char *id, size_t len);
98 int qdisc_set_default(const char *id);
99 
100 void qdisc_hash_add(struct Qdisc *q, bool invisible);
101 void qdisc_hash_del(struct Qdisc *q);
102 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle);
103 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
104 					struct nlattr *tab,
105 					struct netlink_ext_ack *extack);
106 void qdisc_put_rtab(struct qdisc_rate_table *tab);
107 void qdisc_put_stab(struct qdisc_size_table *tab);
108 void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc);
109 bool 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 
113 void __qdisc_run(struct Qdisc *q);
114 
115 static 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 
123 static 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  */
137 static inline unsigned int psched_mtu(const struct net_device *dev)
138 {
139 	return dev->mtu + dev->hard_header_len;
140 }
141 
142 static inline struct net *qdisc_net(struct Qdisc *q)
143 {
144 	return dev_net(q->dev_queue->dev);
145 }
146 
147 struct 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