summaryrefslogtreecommitdiff
path: root/vendor/github.com/vishvananda/netlink/qdisc_linux.go
blob: e182e1cfe6786b8ae5051c4dada79443a4c884e7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
package netlink

import (
	"fmt"
	"io/ioutil"
	"strconv"
	"strings"
	"syscall"

	"github.com/vishvananda/netlink/nl"
	"golang.org/x/sys/unix"
)

// NOTE function is here because it uses other linux functions
func NewNetem(attrs QdiscAttrs, nattrs NetemQdiscAttrs) *Netem {
	var limit uint32 = 1000
	var lossCorr, delayCorr, duplicateCorr uint32
	var reorderProb, reorderCorr uint32
	var corruptProb, corruptCorr uint32

	latency := nattrs.Latency
	loss := Percentage2u32(nattrs.Loss)
	gap := nattrs.Gap
	duplicate := Percentage2u32(nattrs.Duplicate)
	jitter := nattrs.Jitter

	// Correlation
	if latency > 0 && jitter > 0 {
		delayCorr = Percentage2u32(nattrs.DelayCorr)
	}
	if loss > 0 {
		lossCorr = Percentage2u32(nattrs.LossCorr)
	}
	if duplicate > 0 {
		duplicateCorr = Percentage2u32(nattrs.DuplicateCorr)
	}
	// FIXME should validate values(like loss/duplicate are percentages...)
	latency = time2Tick(latency)

	if nattrs.Limit != 0 {
		limit = nattrs.Limit
	}
	// Jitter is only value if latency is > 0
	if latency > 0 {
		jitter = time2Tick(jitter)
	}

	reorderProb = Percentage2u32(nattrs.ReorderProb)
	reorderCorr = Percentage2u32(nattrs.ReorderCorr)

	if reorderProb > 0 {
		// ERROR if lantency == 0
		if gap == 0 {
			gap = 1
		}
	}

	corruptProb = Percentage2u32(nattrs.CorruptProb)
	corruptCorr = Percentage2u32(nattrs.CorruptCorr)

	return &Netem{
		QdiscAttrs:    attrs,
		Latency:       latency,
		DelayCorr:     delayCorr,
		Limit:         limit,
		Loss:          loss,
		LossCorr:      lossCorr,
		Gap:           gap,
		Duplicate:     duplicate,
		DuplicateCorr: duplicateCorr,
		Jitter:        jitter,
		ReorderProb:   reorderProb,
		ReorderCorr:   reorderCorr,
		CorruptProb:   corruptProb,
		CorruptCorr:   corruptCorr,
	}
}

// QdiscDel will delete a qdisc from the system.
// Equivalent to: `tc qdisc del $qdisc`
func QdiscDel(qdisc Qdisc) error {
	return pkgHandle.QdiscDel(qdisc)
}

// QdiscDel will delete a qdisc from the system.
// Equivalent to: `tc qdisc del $qdisc`
func (h *Handle) QdiscDel(qdisc Qdisc) error {
	return h.qdiscModify(unix.RTM_DELQDISC, 0, qdisc)
}

// QdiscChange will change a qdisc in place
// Equivalent to: `tc qdisc change $qdisc`
// The parent and handle MUST NOT be changed.
func QdiscChange(qdisc Qdisc) error {
	return pkgHandle.QdiscChange(qdisc)
}

// QdiscChange will change a qdisc in place
// Equivalent to: `tc qdisc change $qdisc`
// The parent and handle MUST NOT be changed.
func (h *Handle) QdiscChange(qdisc Qdisc) error {
	return h.qdiscModify(unix.RTM_NEWQDISC, 0, qdisc)
}

// QdiscReplace will replace a qdisc to the system.
// Equivalent to: `tc qdisc replace $qdisc`
// The handle MUST change.
func QdiscReplace(qdisc Qdisc) error {
	return pkgHandle.QdiscReplace(qdisc)
}

// QdiscReplace will replace a qdisc to the system.
// Equivalent to: `tc qdisc replace $qdisc`
// The handle MUST change.
func (h *Handle) QdiscReplace(qdisc Qdisc) error {
	return h.qdiscModify(
		unix.RTM_NEWQDISC,
		unix.NLM_F_CREATE|unix.NLM_F_REPLACE,
		qdisc)
}

// QdiscAdd will add a qdisc to the system.
// Equivalent to: `tc qdisc add $qdisc`
func QdiscAdd(qdisc Qdisc) error {
	return pkgHandle.QdiscAdd(qdisc)
}

// QdiscAdd will add a qdisc to the system.
// Equivalent to: `tc qdisc add $qdisc`
func (h *Handle) QdiscAdd(qdisc Qdisc) error {
	return h.qdiscModify(
		unix.RTM_NEWQDISC,
		unix.NLM_F_CREATE|unix.NLM_F_EXCL,
		qdisc)
}

func (h *Handle) qdiscModify(cmd, flags int, qdisc Qdisc) error {
	req := h.newNetlinkRequest(cmd, flags|unix.NLM_F_ACK)
	base := qdisc.Attrs()
	msg := &nl.TcMsg{
		Family:  nl.FAMILY_ALL,
		Ifindex: int32(base.LinkIndex),
		Handle:  base.Handle,
		Parent:  base.Parent,
	}
	req.AddData(msg)

	// When deleting don't bother building the rest of the netlink payload
	if cmd != unix.RTM_DELQDISC {
		if err := qdiscPayload(req, qdisc); err != nil {
			return err
		}
	}

	_, err := req.Execute(unix.NETLINK_ROUTE, 0)
	return err
}

func qdiscPayload(req *nl.NetlinkRequest, qdisc Qdisc) error {

	req.AddData(nl.NewRtAttr(nl.TCA_KIND, nl.ZeroTerminated(qdisc.Type())))

	options := nl.NewRtAttr(nl.TCA_OPTIONS, nil)

	switch qdisc := qdisc.(type) {
	case *Prio:
		tcmap := nl.TcPrioMap{
			Bands:   int32(qdisc.Bands),
			Priomap: qdisc.PriorityMap,
		}
		options = nl.NewRtAttr(nl.TCA_OPTIONS, tcmap.Serialize())
	case *Tbf:
		opt := nl.TcTbfQopt{}
		opt.Rate.Rate = uint32(qdisc.Rate)
		opt.Peakrate.Rate = uint32(qdisc.Peakrate)
		opt.Limit = qdisc.Limit
		opt.Buffer = qdisc.Buffer
		options.AddRtAttr(nl.TCA_TBF_PARMS, opt.Serialize())
		if qdisc.Rate >= uint64(1<<32) {
			options.AddRtAttr(nl.TCA_TBF_RATE64, nl.Uint64Attr(qdisc.Rate))
		}
		if qdisc.Peakrate >= uint64(1<<32) {
			options.AddRtAttr(nl.TCA_TBF_PRATE64, nl.Uint64Attr(qdisc.Peakrate))
		}
		if qdisc.Peakrate > 0 {
			options.AddRtAttr(nl.TCA_TBF_PBURST, nl.Uint32Attr(qdisc.Minburst))
		}
	case *Htb:
		opt := nl.TcHtbGlob{}
		opt.Version = qdisc.Version
		opt.Rate2Quantum = qdisc.Rate2Quantum
		opt.Defcls = qdisc.Defcls
		// TODO: Handle Debug properly. For now default to 0
		opt.Debug = qdisc.Debug
		opt.DirectPkts = qdisc.DirectPkts
		options.AddRtAttr(nl.TCA_HTB_INIT, opt.Serialize())
		// options.AddRtAttr(nl.TCA_HTB_DIRECT_QLEN, opt.Serialize())
	case *Hfsc:
		opt := nl.TcHfscOpt{}
		opt.Defcls = qdisc.Defcls
		options = nl.NewRtAttr(nl.TCA_OPTIONS, opt.Serialize())
	case *Netem:
		opt := nl.TcNetemQopt{}
		opt.Latency = qdisc.Latency
		opt.Limit = qdisc.Limit
		opt.Loss = qdisc.Loss
		opt.Gap = qdisc.Gap
		opt.Duplicate = qdisc.Duplicate
		opt.Jitter = qdisc.Jitter
		options = nl.NewRtAttr(nl.TCA_OPTIONS, opt.Serialize())
		// Correlation
		corr := nl.TcNetemCorr{}
		corr.DelayCorr = qdisc.DelayCorr
		corr.LossCorr = qdisc.LossCorr
		corr.DupCorr = qdisc.DuplicateCorr

		if corr.DelayCorr > 0 || corr.LossCorr > 0 || corr.DupCorr > 0 {
			options.AddRtAttr(nl.TCA_NETEM_CORR, corr.Serialize())
		}
		// Corruption
		corruption := nl.TcNetemCorrupt{}
		corruption.Probability = qdisc.CorruptProb
		corruption.Correlation = qdisc.CorruptCorr
		if corruption.Probability > 0 {
			options.AddRtAttr(nl.TCA_NETEM_CORRUPT, corruption.Serialize())
		}
		// Reorder
		reorder := nl.TcNetemReorder{}
		reorder.Probability = qdisc.ReorderProb
		reorder.Correlation = qdisc.ReorderCorr
		if reorder.Probability > 0 {
			options.AddRtAttr(nl.TCA_NETEM_REORDER, reorder.Serialize())
		}
	case *Ingress:
		// ingress filters must use the proper handle
		if qdisc.Attrs().Parent != HANDLE_INGRESS {
			return fmt.Errorf("Ingress filters must set Parent to HANDLE_INGRESS")
		}
	case *FqCodel:
		options.AddRtAttr(nl.TCA_FQ_CODEL_ECN, nl.Uint32Attr((uint32(qdisc.ECN))))
		if qdisc.Limit > 0 {
			options.AddRtAttr(nl.TCA_FQ_CODEL_LIMIT, nl.Uint32Attr((uint32(qdisc.Limit))))
		}
		if qdisc.Interval > 0 {
			options.AddRtAttr(nl.TCA_FQ_CODEL_INTERVAL, nl.Uint32Attr((uint32(qdisc.Interval))))
		}
		if qdisc.Flows > 0 {
			options.AddRtAttr(nl.TCA_FQ_CODEL_FLOWS, nl.Uint32Attr((uint32(qdisc.Flows))))
		}
		if qdisc.Quantum > 0 {
			options.AddRtAttr(nl.TCA_FQ_CODEL_QUANTUM, nl.Uint32Attr((uint32(qdisc.Quantum))))
		}
		if qdisc.CEThreshold > 0 {
			options.AddRtAttr(nl.TCA_FQ_CODEL_CE_THRESHOLD, nl.Uint32Attr(qdisc.CEThreshold))
		}
		if qdisc.DropBatchSize > 0 {
			options.AddRtAttr(nl.TCA_FQ_CODEL_DROP_BATCH_SIZE, nl.Uint32Attr(qdisc.DropBatchSize))
		}
		if qdisc.MemoryLimit > 0 {
			options.AddRtAttr(nl.TCA_FQ_CODEL_MEMORY_LIMIT, nl.Uint32Attr(qdisc.MemoryLimit))
		}
	case *Fq:
		options.AddRtAttr(nl.TCA_FQ_RATE_ENABLE, nl.Uint32Attr((uint32(qdisc.Pacing))))

		if qdisc.Buckets > 0 {
			options.AddRtAttr(nl.TCA_FQ_BUCKETS_LOG, nl.Uint32Attr((uint32(qdisc.Buckets))))
		}
		if qdisc.LowRateThreshold > 0 {
			options.AddRtAttr(nl.TCA_FQ_LOW_RATE_THRESHOLD, nl.Uint32Attr((uint32(qdisc.LowRateThreshold))))
		}
		if qdisc.Quantum > 0 {
			options.AddRtAttr(nl.TCA_FQ_QUANTUM, nl.Uint32Attr((uint32(qdisc.Quantum))))
		}
		if qdisc.InitialQuantum > 0 {
			options.AddRtAttr(nl.TCA_FQ_INITIAL_QUANTUM, nl.Uint32Attr((uint32(qdisc.InitialQuantum))))
		}
		if qdisc.FlowRefillDelay > 0 {
			options.AddRtAttr(nl.TCA_FQ_FLOW_REFILL_DELAY, nl.Uint32Attr((uint32(qdisc.FlowRefillDelay))))
		}
		if qdisc.FlowPacketLimit > 0 {
			options.AddRtAttr(nl.TCA_FQ_FLOW_PLIMIT, nl.Uint32Attr((uint32(qdisc.FlowPacketLimit))))
		}
		if qdisc.FlowMaxRate > 0 {
			options.AddRtAttr(nl.TCA_FQ_FLOW_MAX_RATE, nl.Uint32Attr((uint32(qdisc.FlowMaxRate))))
		}
		if qdisc.FlowDefaultRate > 0 {
			options.AddRtAttr(nl.TCA_FQ_FLOW_DEFAULT_RATE, nl.Uint32Attr((uint32(qdisc.FlowDefaultRate))))
		}
	case *Sfq:
		opt := nl.TcSfqQoptV1{}
		opt.TcSfqQopt.Quantum = qdisc.Quantum
		opt.TcSfqQopt.Perturb = int32(qdisc.Perturb)
		opt.TcSfqQopt.Limit = qdisc.Limit
		opt.TcSfqQopt.Divisor = qdisc.Divisor

		options = nl.NewRtAttr(nl.TCA_OPTIONS, opt.Serialize())
	default:
		options = nil
	}

	if options != nil {
		req.AddData(options)
	}
	return nil
}

// QdiscList gets a list of qdiscs in the system.
// Equivalent to: `tc qdisc show`.
// The list can be filtered by link.
func QdiscList(link Link) ([]Qdisc, error) {
	return pkgHandle.QdiscList(link)
}

// QdiscList gets a list of qdiscs in the system.
// Equivalent to: `tc qdisc show`.
// The list can be filtered by link.
func (h *Handle) QdiscList(link Link) ([]Qdisc, error) {
	req := h.newNetlinkRequest(unix.RTM_GETQDISC, unix.NLM_F_DUMP)
	index := int32(0)
	if link != nil {
		base := link.Attrs()
		h.ensureIndex(base)
		index = int32(base.Index)
	}
	msg := &nl.TcMsg{
		Family:  nl.FAMILY_ALL,
		Ifindex: index,
	}
	req.AddData(msg)

	msgs, err := req.Execute(unix.NETLINK_ROUTE, unix.RTM_NEWQDISC)
	if err != nil {
		return nil, err
	}

	var res []Qdisc
	for _, m := range msgs {
		msg := nl.DeserializeTcMsg(m)

		attrs, err := nl.ParseRouteAttr(m[msg.Len():])
		if err != nil {
			return nil, err
		}

		// skip qdiscs from other interfaces
		if link != nil && msg.Ifindex != index {
			continue
		}

		base := QdiscAttrs{
			LinkIndex: int(msg.Ifindex),
			Handle:    msg.Handle,
			Parent:    msg.Parent,
			Refcnt:    msg.Info,
		}
		var qdisc Qdisc
		qdiscType := ""
		for _, attr := range attrs {
			switch attr.Attr.Type {
			case nl.TCA_KIND:
				qdiscType = string(attr.Value[:len(attr.Value)-1])
				switch qdiscType {
				case "pfifo_fast":
					qdisc = &PfifoFast{}
				case "prio":
					qdisc = &Prio{}
				case "tbf":
					qdisc = &Tbf{}
				case "ingress":
					qdisc = &Ingress{}
				case "htb":
					qdisc = &Htb{}
				case "fq":
					qdisc = &Fq{}
				case "hfsc":
					qdisc = &Hfsc{}
				case "fq_codel":
					qdisc = &FqCodel{}
				case "netem":
					qdisc = &Netem{}
				case "sfq":
					qdisc = &Sfq{}
				default:
					qdisc = &GenericQdisc{QdiscType: qdiscType}
				}
			case nl.TCA_OPTIONS:
				switch qdiscType {
				case "pfifo_fast":
					// pfifo returns TcPrioMap directly without wrapping it in rtattr
					if err := parsePfifoFastData(qdisc, attr.Value); err != nil {
						return nil, err
					}
				case "prio":
					// prio returns TcPrioMap directly without wrapping it in rtattr
					if err := parsePrioData(qdisc, attr.Value); err != nil {
						return nil, err
					}
				case "tbf":
					data, err := nl.ParseRouteAttr(attr.Value)
					if err != nil {
						return nil, err
					}
					if err := parseTbfData(qdisc, data); err != nil {
						return nil, err
					}
				case "hfsc":
					if err := parseHfscData(qdisc, attr.Value); err != nil {
						return nil, err
					}
				case "htb":
					data, err := nl.ParseRouteAttr(attr.Value)
					if err != nil {
						return nil, err
					}
					if err := parseHtbData(qdisc, data); err != nil {
						return nil, err
					}
				case "fq":
					data, err := nl.ParseRouteAttr(attr.Value)
					if err != nil {
						return nil, err
					}
					if err := parseFqData(qdisc, data); err != nil {
						return nil, err
					}
				case "fq_codel":
					data, err := nl.ParseRouteAttr(attr.Value)
					if err != nil {
						return nil, err
					}
					if err := parseFqCodelData(qdisc, data); err != nil {
						return nil, err
					}
				case "netem":
					if err := parseNetemData(qdisc, attr.Value); err != nil {
						return nil, err
					}
				case "sfq":
					if err := parseSfqData(qdisc, attr.Value); err != nil {
						return nil, err
					}

					// no options for ingress
				}
			}
		}
		*qdisc.Attrs() = base
		res = append(res, qdisc)
	}

	return res, nil
}

func parsePfifoFastData(qdisc Qdisc, value []byte) error {
	pfifo := qdisc.(*PfifoFast)
	tcmap := nl.DeserializeTcPrioMap(value)
	pfifo.PriorityMap = tcmap.Priomap
	pfifo.Bands = uint8(tcmap.Bands)
	return nil
}

func parsePrioData(qdisc Qdisc, value []byte) error {
	prio := qdisc.(*Prio)
	tcmap := nl.DeserializeTcPrioMap(value)
	prio.PriorityMap = tcmap.Priomap
	prio.Bands = uint8(tcmap.Bands)
	return nil
}

func parseHtbData(qdisc Qdisc, data []syscall.NetlinkRouteAttr) error {
	htb := qdisc.(*Htb)
	for _, datum := range data {
		switch datum.Attr.Type {
		case nl.TCA_HTB_INIT:
			opt := nl.DeserializeTcHtbGlob(datum.Value)
			htb.Version = opt.Version
			htb.Rate2Quantum = opt.Rate2Quantum
			htb.Defcls = opt.Defcls
			htb.Debug = opt.Debug
			htb.DirectPkts = opt.DirectPkts
		case nl.TCA_HTB_DIRECT_QLEN:
			// TODO
			//htb.DirectQlen = native.uint32(datum.Value)
		}
	}
	return nil
}

func parseFqCodelData(qdisc Qdisc, data []syscall.NetlinkRouteAttr) error {
	fqCodel := qdisc.(*FqCodel)
	for _, datum := range data {

		switch datum.Attr.Type {
		case nl.TCA_FQ_CODEL_TARGET:
			fqCodel.Target = native.Uint32(datum.Value)
		case nl.TCA_FQ_CODEL_LIMIT:
			fqCodel.Limit = native.Uint32(datum.Value)
		case nl.TCA_FQ_CODEL_INTERVAL:
			fqCodel.Interval = native.Uint32(datum.Value)
		case nl.TCA_FQ_CODEL_ECN:
			fqCodel.ECN = native.Uint32(datum.Value)
		case nl.TCA_FQ_CODEL_FLOWS:
			fqCodel.Flows = native.Uint32(datum.Value)
		case nl.TCA_FQ_CODEL_QUANTUM:
			fqCodel.Quantum = native.Uint32(datum.Value)
		case nl.TCA_FQ_CODEL_CE_THRESHOLD:
			fqCodel.CEThreshold = native.Uint32(datum.Value)
		case nl.TCA_FQ_CODEL_DROP_BATCH_SIZE:
			fqCodel.DropBatchSize = native.Uint32(datum.Value)
		case nl.TCA_FQ_CODEL_MEMORY_LIMIT:
			fqCodel.MemoryLimit = native.Uint32(datum.Value)
		}
	}
	return nil
}

func parseHfscData(qdisc Qdisc, data []byte) error {
	Hfsc := qdisc.(*Hfsc)
	Hfsc.Defcls = native.Uint16(data)
	return nil
}

func parseFqData(qdisc Qdisc, data []syscall.NetlinkRouteAttr) error {
	fq := qdisc.(*Fq)
	for _, datum := range data {
		switch datum.Attr.Type {
		case nl.TCA_FQ_BUCKETS_LOG:
			fq.Buckets = native.Uint32(datum.Value)
		case nl.TCA_FQ_LOW_RATE_THRESHOLD:
			fq.LowRateThreshold = native.Uint32(datum.Value)
		case nl.TCA_FQ_QUANTUM:
			fq.Quantum = native.Uint32(datum.Value)
		case nl.TCA_FQ_RATE_ENABLE:
			fq.Pacing = native.Uint32(datum.Value)
		case nl.TCA_FQ_INITIAL_QUANTUM:
			fq.InitialQuantum = native.Uint32(datum.Value)
		case nl.TCA_FQ_ORPHAN_MASK:
			// TODO
		case nl.TCA_FQ_FLOW_REFILL_DELAY:
			fq.FlowRefillDelay = native.Uint32(datum.Value)
		case nl.TCA_FQ_FLOW_PLIMIT:
			fq.FlowPacketLimit = native.Uint32(datum.Value)
		case nl.TCA_FQ_PLIMIT:
			fq.PacketLimit = native.Uint32(datum.Value)
		case nl.TCA_FQ_FLOW_MAX_RATE:
			fq.FlowMaxRate = native.Uint32(datum.Value)
		case nl.TCA_FQ_FLOW_DEFAULT_RATE:
			fq.FlowDefaultRate = native.Uint32(datum.Value)
		}
	}
	return nil
}

func parseNetemData(qdisc Qdisc, value []byte) error {
	netem := qdisc.(*Netem)
	opt := nl.DeserializeTcNetemQopt(value)
	netem.Latency = opt.Latency
	netem.Limit = opt.Limit
	netem.Loss = opt.Loss
	netem.Gap = opt.Gap
	netem.Duplicate = opt.Duplicate
	netem.Jitter = opt.Jitter
	data, err := nl.ParseRouteAttr(value[nl.SizeofTcNetemQopt:])
	if err != nil {
		return err
	}
	for _, datum := range data {
		switch datum.Attr.Type {
		case nl.TCA_NETEM_CORR:
			opt := nl.DeserializeTcNetemCorr(datum.Value)
			netem.DelayCorr = opt.DelayCorr
			netem.LossCorr = opt.LossCorr
			netem.DuplicateCorr = opt.DupCorr
		case nl.TCA_NETEM_CORRUPT:
			opt := nl.DeserializeTcNetemCorrupt(datum.Value)
			netem.CorruptProb = opt.Probability
			netem.CorruptCorr = opt.Correlation
		case nl.TCA_NETEM_REORDER:
			opt := nl.DeserializeTcNetemReorder(datum.Value)
			netem.ReorderProb = opt.Probability
			netem.ReorderCorr = opt.Correlation
		}
	}
	return nil
}

func parseTbfData(qdisc Qdisc, data []syscall.NetlinkRouteAttr) error {
	tbf := qdisc.(*Tbf)
	for _, datum := range data {
		switch datum.Attr.Type {
		case nl.TCA_TBF_PARMS:
			opt := nl.DeserializeTcTbfQopt(datum.Value)
			tbf.Rate = uint64(opt.Rate.Rate)
			tbf.Peakrate = uint64(opt.Peakrate.Rate)
			tbf.Limit = opt.Limit
			tbf.Buffer = opt.Buffer
		case nl.TCA_TBF_RATE64:
			tbf.Rate = native.Uint64(datum.Value[0:8])
		case nl.TCA_TBF_PRATE64:
			tbf.Peakrate = native.Uint64(datum.Value[0:8])
		case nl.TCA_TBF_PBURST:
			tbf.Minburst = native.Uint32(datum.Value[0:4])
		}
	}
	return nil
}

func parseSfqData(qdisc Qdisc, value []byte) error {
	sfq := qdisc.(*Sfq)
	opt := nl.DeserializeTcSfqQoptV1(value)
	sfq.Quantum = opt.TcSfqQopt.Quantum
	sfq.Perturb = uint8(opt.TcSfqQopt.Perturb)
	sfq.Limit = opt.TcSfqQopt.Limit
	sfq.Divisor = opt.TcSfqQopt.Divisor

	return nil
}

const (
	TIME_UNITS_PER_SEC = 1000000
)

var (
	tickInUsec  float64
	clockFactor float64
	hz          float64
)

func initClock() {
	data, err := ioutil.ReadFile("/proc/net/psched")
	if err != nil {
		return
	}
	parts := strings.Split(strings.TrimSpace(string(data)), " ")
	if len(parts) < 4 {
		return
	}
	var vals [4]uint64
	for i := range vals {
		val, err := strconv.ParseUint(parts[i], 16, 32)
		if err != nil {
			return
		}
		vals[i] = val
	}
	// compatibility
	if vals[2] == 1000000000 {
		vals[0] = vals[1]
	}
	clockFactor = float64(vals[2]) / TIME_UNITS_PER_SEC
	tickInUsec = float64(vals[0]) / float64(vals[1]) * clockFactor
	if vals[2] == 1000000 {
		// ref https://git.kernel.org/pub/scm/network/iproute2/iproute2.git/tree/lib/utils.c#n963
		hz = float64(vals[3])
	} else {
		hz = 100
	}
}

func TickInUsec() float64 {
	if tickInUsec == 0.0 {
		initClock()
	}
	return tickInUsec
}

func ClockFactor() float64 {
	if clockFactor == 0.0 {
		initClock()
	}
	return clockFactor
}

func Hz() float64 {
	if hz == 0.0 {
		initClock()
	}
	return hz
}

func time2Tick(time uint32) uint32 {
	return uint32(float64(time) * TickInUsec())
}

func tick2Time(tick uint32) uint32 {
	return uint32(float64(tick) / TickInUsec())
}

func time2Ktime(time uint32) uint32 {
	return uint32(float64(time) * ClockFactor())
}

func ktime2Time(ktime uint32) uint32 {
	return uint32(float64(ktime) / ClockFactor())
}

func burst(rate uint64, buffer uint32) uint32 {
	return uint32(float64(rate) * float64(tick2Time(buffer)) / TIME_UNITS_PER_SEC)
}

func latency(rate uint64, limit, buffer uint32) float64 {
	return TIME_UNITS_PER_SEC*(float64(limit)/float64(rate)) - float64(tick2Time(buffer))
}

func Xmittime(rate uint64, size uint32) uint32 {
	// https://git.kernel.org/pub/scm/network/iproute2/iproute2.git/tree/tc/tc_core.c#n62
	return time2Tick(uint32(TIME_UNITS_PER_SEC * (float64(size) / float64(rate))))
}

func Xmitsize(rate uint64, ticks uint32) uint32 {
	return uint32((float64(rate) * float64(tick2Time(ticks))) / TIME_UNITS_PER_SEC)
}