2 * net/sched/sch_prio.c Simple 3-band priority "scheduler".
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 * Fixes: 19990609: J Hadi Salim <hadi@nortelnetworks.com>:
11 * Init -- EINVAL when opt undefined
14 #include <linux/module.h>
15 #include <linux/types.h>
16 #include <linux/kernel.h>
17 #include <linux/string.h>
18 #include <linux/errno.h>
19 #include <linux/skbuff.h>
20 #include <net/netlink.h>
21 #include <net/pkt_sched.h>
24 struct prio_sched_data
27 struct tcf_proto
*filter_list
;
28 u8 prio2band
[TC_PRIO_MAX
+1];
29 struct Qdisc
*queues
[TCQ_PRIO_BANDS
];
34 prio_classify(struct sk_buff
*skb
, struct Qdisc
*sch
, int *qerr
)
36 struct prio_sched_data
*q
= qdisc_priv(sch
);
37 u32 band
= skb
->priority
;
38 struct tcf_result res
;
41 *qerr
= NET_XMIT_SUCCESS
| __NET_XMIT_BYPASS
;
42 if (TC_H_MAJ(skb
->priority
) != sch
->handle
) {
43 err
= tc_classify(skb
, q
->filter_list
, &res
);
44 #ifdef CONFIG_NET_CLS_ACT
48 *qerr
= NET_XMIT_SUCCESS
| __NET_XMIT_STOLEN
;
53 if (!q
->filter_list
|| err
< 0) {
56 return q
->queues
[q
->prio2band
[band
&TC_PRIO_MAX
]];
60 band
= TC_H_MIN(band
) - 1;
62 return q
->queues
[q
->prio2band
[0]];
64 return q
->queues
[band
];
68 prio_enqueue(struct sk_buff
*skb
, struct Qdisc
*sch
)
73 qdisc
= prio_classify(skb
, sch
, &ret
);
74 #ifdef CONFIG_NET_CLS_ACT
77 if (ret
& __NET_XMIT_BYPASS
)
84 ret
= qdisc_enqueue(skb
, qdisc
);
85 if (ret
== NET_XMIT_SUCCESS
) {
86 sch
->bstats
.bytes
+= qdisc_pkt_len(skb
);
87 sch
->bstats
.packets
++;
89 return NET_XMIT_SUCCESS
;
91 if (net_xmit_drop_count(ret
))
96 static struct sk_buff
*prio_peek(struct Qdisc
*sch
)
98 struct prio_sched_data
*q
= qdisc_priv(sch
);
101 for (prio
= 0; prio
< q
->bands
; prio
++) {
102 struct Qdisc
*qdisc
= q
->queues
[prio
];
103 struct sk_buff
*skb
= qdisc
->ops
->peek(qdisc
);
110 static struct sk_buff
*prio_dequeue(struct Qdisc
* sch
)
112 struct prio_sched_data
*q
= qdisc_priv(sch
);
115 for (prio
= 0; prio
< q
->bands
; prio
++) {
116 struct Qdisc
*qdisc
= q
->queues
[prio
];
117 struct sk_buff
*skb
= qdisc
->dequeue(qdisc
);
127 static unsigned int prio_drop(struct Qdisc
* sch
)
129 struct prio_sched_data
*q
= qdisc_priv(sch
);
134 for (prio
= q
->bands
-1; prio
>= 0; prio
--) {
135 qdisc
= q
->queues
[prio
];
136 if (qdisc
->ops
->drop
&& (len
= qdisc
->ops
->drop(qdisc
)) != 0) {
146 prio_reset(struct Qdisc
* sch
)
149 struct prio_sched_data
*q
= qdisc_priv(sch
);
151 for (prio
=0; prio
<q
->bands
; prio
++)
152 qdisc_reset(q
->queues
[prio
]);
157 prio_destroy(struct Qdisc
* sch
)
160 struct prio_sched_data
*q
= qdisc_priv(sch
);
162 tcf_destroy_chain(&q
->filter_list
);
163 for (prio
=0; prio
<q
->bands
; prio
++)
164 qdisc_destroy(q
->queues
[prio
]);
167 static int prio_tune(struct Qdisc
*sch
, struct nlattr
*opt
)
169 struct prio_sched_data
*q
= qdisc_priv(sch
);
170 struct tc_prio_qopt
*qopt
;
173 if (nla_len(opt
) < sizeof(*qopt
))
175 qopt
= nla_data(opt
);
177 if (qopt
->bands
> TCQ_PRIO_BANDS
|| qopt
->bands
< 2)
180 for (i
=0; i
<=TC_PRIO_MAX
; i
++) {
181 if (qopt
->priomap
[i
] >= qopt
->bands
)
186 q
->bands
= qopt
->bands
;
187 memcpy(q
->prio2band
, qopt
->priomap
, TC_PRIO_MAX
+1);
189 for (i
=q
->bands
; i
<TCQ_PRIO_BANDS
; i
++) {
190 struct Qdisc
*child
= q
->queues
[i
];
191 q
->queues
[i
] = &noop_qdisc
;
192 if (child
!= &noop_qdisc
) {
193 qdisc_tree_decrease_qlen(child
, child
->q
.qlen
);
194 qdisc_destroy(child
);
197 sch_tree_unlock(sch
);
199 for (i
=0; i
<q
->bands
; i
++) {
200 if (q
->queues
[i
] == &noop_qdisc
) {
201 struct Qdisc
*child
, *old
;
202 child
= qdisc_create_dflt(qdisc_dev(sch
), sch
->dev_queue
,
204 TC_H_MAKE(sch
->handle
, i
+ 1));
208 q
->queues
[i
] = child
;
210 if (old
!= &noop_qdisc
) {
211 qdisc_tree_decrease_qlen(old
,
215 sch_tree_unlock(sch
);
222 static int prio_init(struct Qdisc
*sch
, struct nlattr
*opt
)
224 struct prio_sched_data
*q
= qdisc_priv(sch
);
227 for (i
=0; i
<TCQ_PRIO_BANDS
; i
++)
228 q
->queues
[i
] = &noop_qdisc
;
235 if ((err
= prio_tune(sch
, opt
)) != 0)
241 static int prio_dump(struct Qdisc
*sch
, struct sk_buff
*skb
)
243 struct prio_sched_data
*q
= qdisc_priv(sch
);
244 unsigned char *b
= skb_tail_pointer(skb
);
245 struct tc_prio_qopt opt
;
247 opt
.bands
= q
->bands
;
248 memcpy(&opt
.priomap
, q
->prio2band
, TC_PRIO_MAX
+1);
250 NLA_PUT(skb
, TCA_OPTIONS
, sizeof(opt
), &opt
);
259 static int prio_graft(struct Qdisc
*sch
, unsigned long arg
, struct Qdisc
*new,
262 struct prio_sched_data
*q
= qdisc_priv(sch
);
263 unsigned long band
= arg
- 1;
269 *old
= q
->queues
[band
];
270 q
->queues
[band
] = new;
271 qdisc_tree_decrease_qlen(*old
, (*old
)->q
.qlen
);
273 sch_tree_unlock(sch
);
278 static struct Qdisc
*
279 prio_leaf(struct Qdisc
*sch
, unsigned long arg
)
281 struct prio_sched_data
*q
= qdisc_priv(sch
);
282 unsigned long band
= arg
- 1;
284 return q
->queues
[band
];
287 static unsigned long prio_get(struct Qdisc
*sch
, u32 classid
)
289 struct prio_sched_data
*q
= qdisc_priv(sch
);
290 unsigned long band
= TC_H_MIN(classid
);
292 if (band
- 1 >= q
->bands
)
297 static unsigned long prio_bind(struct Qdisc
*sch
, unsigned long parent
, u32 classid
)
299 return prio_get(sch
, classid
);
303 static void prio_put(struct Qdisc
*q
, unsigned long cl
)
308 static int prio_dump_class(struct Qdisc
*sch
, unsigned long cl
, struct sk_buff
*skb
,
311 struct prio_sched_data
*q
= qdisc_priv(sch
);
313 tcm
->tcm_handle
|= TC_H_MIN(cl
);
314 tcm
->tcm_info
= q
->queues
[cl
-1]->handle
;
318 static int prio_dump_class_stats(struct Qdisc
*sch
, unsigned long cl
,
321 struct prio_sched_data
*q
= qdisc_priv(sch
);
324 cl_q
= q
->queues
[cl
- 1];
325 cl_q
->qstats
.qlen
= cl_q
->q
.qlen
;
326 if (gnet_stats_copy_basic(d
, &cl_q
->bstats
) < 0 ||
327 gnet_stats_copy_queue(d
, &cl_q
->qstats
) < 0)
333 static void prio_walk(struct Qdisc
*sch
, struct qdisc_walker
*arg
)
335 struct prio_sched_data
*q
= qdisc_priv(sch
);
341 for (prio
= 0; prio
< q
->bands
; prio
++) {
342 if (arg
->count
< arg
->skip
) {
346 if (arg
->fn(sch
, prio
+1, arg
) < 0) {
354 static struct tcf_proto
** prio_find_tcf(struct Qdisc
*sch
, unsigned long cl
)
356 struct prio_sched_data
*q
= qdisc_priv(sch
);
360 return &q
->filter_list
;
363 static const struct Qdisc_class_ops prio_class_ops
= {
369 .tcf_chain
= prio_find_tcf
,
370 .bind_tcf
= prio_bind
,
371 .unbind_tcf
= prio_put
,
372 .dump
= prio_dump_class
,
373 .dump_stats
= prio_dump_class_stats
,
376 static struct Qdisc_ops prio_qdisc_ops __read_mostly
= {
378 .cl_ops
= &prio_class_ops
,
380 .priv_size
= sizeof(struct prio_sched_data
),
381 .enqueue
= prio_enqueue
,
382 .dequeue
= prio_dequeue
,
387 .destroy
= prio_destroy
,
390 .owner
= THIS_MODULE
,
393 static int __init
prio_module_init(void)
395 return register_qdisc(&prio_qdisc_ops
);
398 static void __exit
prio_module_exit(void)
400 unregister_qdisc(&prio_qdisc_ops
);
403 module_init(prio_module_init
)
404 module_exit(prio_module_exit
)
406 MODULE_LICENSE("GPL");