aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/go/_std_1.21/src/internal/profile/profile.go
blob: c779bb2b11364d25e8681cebf9adca3ac016c9e8 (plain) (blame)
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
// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Package profile provides a representation of
// github.com/google/pprof/proto/profile.proto and
// methods to encode/decode/merge profiles in this format.
package profile

import (
	"bytes"
	"compress/gzip"
	"fmt"
	"internal/lazyregexp"
	"io"
	"strings"
	"time"
)

// Profile is an in-memory representation of profile.proto.
type Profile struct {
	SampleType        []*ValueType
	DefaultSampleType string
	Sample            []*Sample
	Mapping           []*Mapping
	Location          []*Location
	Function          []*Function
	Comments          []string

	DropFrames string
	KeepFrames string

	TimeNanos     int64
	DurationNanos int64
	PeriodType    *ValueType
	Period        int64

	commentX           []int64
	dropFramesX        int64
	keepFramesX        int64
	stringTable        []string
	defaultSampleTypeX int64
}

// ValueType corresponds to Profile.ValueType
type ValueType struct {
	Type string // cpu, wall, inuse_space, etc
	Unit string // seconds, nanoseconds, bytes, etc

	typeX int64
	unitX int64
}

// Sample corresponds to Profile.Sample
type Sample struct {
	Location []*Location
	Value    []int64
	Label    map[string][]string
	NumLabel map[string][]int64
	NumUnit  map[string][]string

	locationIDX []uint64
	labelX      []Label
}

// Label corresponds to Profile.Label
type Label struct {
	keyX int64
	// Exactly one of the two following values must be set
	strX int64
	numX int64 // Integer value for this label
}

// Mapping corresponds to Profile.Mapping
type Mapping struct {
	ID              uint64
	Start           uint64
	Limit           uint64
	Offset          uint64
	File            string
	BuildID         string
	HasFunctions    bool
	HasFilenames    bool
	HasLineNumbers  bool
	HasInlineFrames bool

	fileX    int64
	buildIDX int64
}

// Location corresponds to Profile.Location
type Location struct {
	ID       uint64
	Mapping  *Mapping
	Address  uint64
	Line     []Line
	IsFolded bool

	mappingIDX uint64
}

// Line corresponds to Profile.Line
type Line struct {
	Function *Function
	Line     int64

	functionIDX uint64
}

// Function corresponds to Profile.Function
type Function struct {
	ID         uint64
	Name       string
	SystemName string
	Filename   string
	StartLine  int64

	nameX       int64
	systemNameX int64
	filenameX   int64
}

// Parse parses a profile and checks for its validity. The input
// may be a gzip-compressed encoded protobuf or one of many legacy
// profile formats which may be unsupported in the future.
func Parse(r io.Reader) (*Profile, error) {
	orig, err := io.ReadAll(r)
	if err != nil {
		return nil, err
	}

	var p *Profile
	if len(orig) >= 2 && orig[0] == 0x1f && orig[1] == 0x8b {
		gz, err := gzip.NewReader(bytes.NewBuffer(orig))
		if err != nil {
			return nil, fmt.Errorf("decompressing profile: %v", err)
		}
		data, err := io.ReadAll(gz)
		if err != nil {
			return nil, fmt.Errorf("decompressing profile: %v", err)
		}
		orig = data
	}
	if p, err = parseUncompressed(orig); err != nil {
		if p, err = parseLegacy(orig); err != nil {
			return nil, fmt.Errorf("parsing profile: %v", err)
		}
	}

	if err := p.CheckValid(); err != nil {
		return nil, fmt.Errorf("malformed profile: %v", err)
	}
	return p, nil
}

var errUnrecognized = fmt.Errorf("unrecognized profile format")
var errMalformed = fmt.Errorf("malformed profile format")

func parseLegacy(data []byte) (*Profile, error) {
	parsers := []func([]byte) (*Profile, error){
		parseCPU,
		parseHeap,
		parseGoCount, // goroutine, threadcreate
		parseThread,
		parseContention,
	}

	for _, parser := range parsers {
		p, err := parser(data)
		if err == nil {
			p.setMain()
			p.addLegacyFrameInfo()
			return p, nil
		}
		if err != errUnrecognized {
			return nil, err
		}
	}
	return nil, errUnrecognized
}

func parseUncompressed(data []byte) (*Profile, error) {
	p := &Profile{}
	if err := unmarshal(data, p); err != nil {
		return nil, err
	}

	if err := p.postDecode(); err != nil {
		return nil, err
	}

	return p, nil
}

var libRx = lazyregexp.New(`([.]so$|[.]so[._][0-9]+)`)

// setMain scans Mapping entries and guesses which entry is main
// because legacy profiles don't obey the convention of putting main
// first.
func (p *Profile) setMain() {
	for i := 0; i < len(p.Mapping); i++ {
		file := strings.TrimSpace(strings.ReplaceAll(p.Mapping[i].File, "(deleted)", ""))
		if len(file) == 0 {
			continue
		}
		if len(libRx.FindStringSubmatch(file)) > 0 {
			continue
		}
		if strings.HasPrefix(file, "[") {
			continue
		}
		// Swap what we guess is main to position 0.
		p.Mapping[i], p.Mapping[0] = p.Mapping[0], p.Mapping[i]
		break
	}
}

// Write writes the profile as a gzip-compressed marshaled protobuf.
func (p *Profile) Write(w io.Writer) error {
	p.preEncode()
	b := marshal(p)
	zw := gzip.NewWriter(w)
	defer zw.Close()
	_, err := zw.Write(b)
	return err
}

// CheckValid tests whether the profile is valid. Checks include, but are
// not limited to:
//   - len(Profile.Sample[n].value) == len(Profile.value_unit)
//   - Sample.id has a corresponding Profile.Location
func (p *Profile) CheckValid() error {
	// Check that sample values are consistent
	sampleLen := len(p.SampleType)
	if sampleLen == 0 && len(p.Sample) != 0 {
		return fmt.Errorf("missing sample type information")
	}
	for _, s := range p.Sample {
		if len(s.Value) != sampleLen {
			return fmt.Errorf("mismatch: sample has: %d values vs. %d types", len(s.Value), len(p.SampleType))
		}
	}

	// Check that all mappings/locations/functions are in the tables
	// Check that there are no duplicate ids
	mappings := make(map[uint64]*Mapping, len(p.Mapping))
	for _, m := range p.Mapping {
		if m.ID == 0 {
			return fmt.Errorf("found mapping with reserved ID=0")
		}
		if mappings[m.ID] != nil {
			return fmt.Errorf("multiple mappings with same id: %d", m.ID)
		}
		mappings[m.ID] = m
	}
	functions := make(map[uint64]*Function, len(p.Function))
	for _, f := range p.Function {
		if f.ID == 0 {
			return fmt.Errorf("found function with reserved ID=0")
		}
		if functions[f.ID] != nil {
			return fmt.Errorf("multiple functions with same id: %d", f.ID)
		}
		functions[f.ID] = f
	}
	locations := make(map[uint64]*Location, len(p.Location))
	for _, l := range p.Location {
		if l.ID == 0 {
			return fmt.Errorf("found location with reserved id=0")
		}
		if locations[l.ID] != nil {
			return fmt.Errorf("multiple locations with same id: %d", l.ID)
		}
		locations[l.ID] = l
		if m := l.Mapping; m != nil {
			if m.ID == 0 || mappings[m.ID] != m {
				return fmt.Errorf("inconsistent mapping %p: %d", m, m.ID)
			}
		}
		for _, ln := range l.Line {
			if f := ln.Function; f != nil {
				if f.ID == 0 || functions[f.ID] != f {
					return fmt.Errorf("inconsistent function %p: %d", f, f.ID)
				}
			}
		}
	}
	return nil
}

// Aggregate merges the locations in the profile into equivalence
// classes preserving the request attributes. It also updates the
// samples to point to the merged locations.
func (p *Profile) Aggregate(inlineFrame, function, filename, linenumber, address bool) error {
	for _, m := range p.Mapping {
		m.HasInlineFrames = m.HasInlineFrames && inlineFrame
		m.HasFunctions = m.HasFunctions && function
		m.HasFilenames = m.HasFilenames && filename
		m.HasLineNumbers = m.HasLineNumbers && linenumber
	}

	// Aggregate functions
	if !function || !filename {
		for _, f := range p.Function {
			if !function {
				f.Name = ""
				f.SystemName = ""
			}
			if !filename {
				f.Filename = ""
			}
		}
	}

	// Aggregate locations
	if !inlineFrame || !address || !linenumber {
		for _, l := range p.Location {
			if !inlineFrame && len(l.Line) > 1 {
				l.Line = l.Line[len(l.Line)-1:]
			}
			if !linenumber {
				for i := range l.Line {
					l.Line[i].Line = 0
				}
			}
			if !address {
				l.Address = 0
			}
		}
	}

	return p.CheckValid()
}

// Print dumps a text representation of a profile. Intended mainly
// for debugging purposes.
func (p *Profile) String() string {

	ss := make([]string, 0, len(p.Sample)+len(p.Mapping)+len(p.Location))
	if pt := p.PeriodType; pt != nil {
		ss = append(ss, fmt.Sprintf("PeriodType: %s %s", pt.Type, pt.Unit))
	}
	ss = append(ss, fmt.Sprintf("Period: %d", p.Period))
	if p.TimeNanos != 0 {
		ss = append(ss, fmt.Sprintf("Time: %v", time.Unix(0, p.TimeNanos)))
	}
	if p.DurationNanos != 0 {
		ss = append(ss, fmt.Sprintf("Duration: %v", time.Duration(p.DurationNanos)))
	}

	ss = append(ss, "Samples:")
	var sh1 string
	for _, s := range p.SampleType {
		sh1 = sh1 + fmt.Sprintf("%s/%s ", s.Type, s.Unit)
	}
	ss = append(ss, strings.TrimSpace(sh1))
	for _, s := range p.Sample {
		var sv string
		for _, v := range s.Value {
			sv = fmt.Sprintf("%s %10d", sv, v)
		}
		sv = sv + ": "
		for _, l := range s.Location {
			sv = sv + fmt.Sprintf("%d ", l.ID)
		}
		ss = append(ss, sv)
		const labelHeader = "                "
		if len(s.Label) > 0 {
			ls := labelHeader
			for k, v := range s.Label {
				ls = ls + fmt.Sprintf("%s:%v ", k, v)
			}
			ss = append(ss, ls)
		}
		if len(s.NumLabel) > 0 {
			ls := labelHeader
			for k, v := range s.NumLabel {
				ls = ls + fmt.Sprintf("%s:%v ", k, v)
			}
			ss = append(ss, ls)
		}
	}

	ss = append(ss, "Locations")
	for _, l := range p.Location {
		locStr := fmt.Sprintf("%6d: %#x ", l.ID, l.Address)
		if m := l.Mapping; m != nil {
			locStr = locStr + fmt.Sprintf("M=%d ", m.ID)
		}
		if len(l.Line) == 0 {
			ss = append(ss, locStr)
		}
		for li := range l.Line {
			lnStr := "??"
			if fn := l.Line[li].Function; fn != nil {
				lnStr = fmt.Sprintf("%s %s:%d s=%d",
					fn.Name,
					fn.Filename,
					l.Line[li].Line,
					fn.StartLine)
				if fn.Name != fn.SystemName {
					lnStr = lnStr + "(" + fn.SystemName + ")"
				}
			}
			ss = append(ss, locStr+lnStr)
			// Do not print location details past the first line
			locStr = "             "
		}
	}

	ss = append(ss, "Mappings")
	for _, m := range p.Mapping {
		bits := ""
		if m.HasFunctions {
			bits += "[FN]"
		}
		if m.HasFilenames {
			bits += "[FL]"
		}
		if m.HasLineNumbers {
			bits += "[LN]"
		}
		if m.HasInlineFrames {
			bits += "[IN]"
		}
		ss = append(ss, fmt.Sprintf("%d: %#x/%#x/%#x %s %s %s",
			m.ID,
			m.Start, m.Limit, m.Offset,
			m.File,
			m.BuildID,
			bits))
	}

	return strings.Join(ss, "\n") + "\n"
}

// Merge adds profile p adjusted by ratio r into profile p. Profiles
// must be compatible (same Type and SampleType).
// TODO(rsilvera): consider normalizing the profiles based on the
// total samples collected.
func (p *Profile) Merge(pb *Profile, r float64) error {
	if err := p.Compatible(pb); err != nil {
		return err
	}

	pb = pb.Copy()

	// Keep the largest of the two periods.
	if pb.Period > p.Period {
		p.Period = pb.Period
	}

	p.DurationNanos += pb.DurationNanos

	p.Mapping = append(p.Mapping, pb.Mapping...)
	for i, m := range p.Mapping {
		m.ID = uint64(i + 1)
	}
	p.Location = append(p.Location, pb.Location...)
	for i, l := range p.Location {
		l.ID = uint64(i + 1)
	}
	p.Function = append(p.Function, pb.Function...)
	for i, f := range p.Function {
		f.ID = uint64(i + 1)
	}

	if r != 1.0 {
		for _, s := range pb.Sample {
			for i, v := range s.Value {
				s.Value[i] = int64((float64(v) * r))
			}
		}
	}
	p.Sample = append(p.Sample, pb.Sample...)
	return p.CheckValid()
}

// Compatible determines if two profiles can be compared/merged.
// returns nil if the profiles are compatible; otherwise an error with
// details on the incompatibility.
func (p *Profile) Compatible(pb *Profile) error {
	if !compatibleValueTypes(p.PeriodType, pb.PeriodType) {
		return fmt.Errorf("incompatible period types %v and %v", p.PeriodType, pb.PeriodType)
	}

	if len(p.SampleType) != len(pb.SampleType) {
		return fmt.Errorf("incompatible sample types %v and %v", p.SampleType, pb.SampleType)
	}

	for i := range p.SampleType {
		if !compatibleValueTypes(p.SampleType[i], pb.SampleType[i]) {
			return fmt.Errorf("incompatible sample types %v and %v", p.SampleType, pb.SampleType)
		}
	}

	return nil
}

// HasFunctions determines if all locations in this profile have
// symbolized function information.
func (p *Profile) HasFunctions() bool {
	for _, l := range p.Location {
		if l.Mapping == nil || !l.Mapping.HasFunctions {
			return false
		}
	}
	return true
}

// HasFileLines determines if all locations in this profile have
// symbolized file and line number information.
func (p *Profile) HasFileLines() bool {
	for _, l := range p.Location {
		if l.Mapping == nil || (!l.Mapping.HasFilenames || !l.Mapping.HasLineNumbers) {
			return false
		}
	}
	return true
}

func compatibleValueTypes(v1, v2 *ValueType) bool {
	if v1 == nil || v2 == nil {
		return true // No grounds to disqualify.
	}
	return v1.Type == v2.Type && v1.Unit == v2.Unit
}

// Copy makes a fully independent copy of a profile.
func (p *Profile) Copy() *Profile {
	p.preEncode()
	b := marshal(p)

	pp := &Profile{}
	if err := unmarshal(b, pp); err != nil {
		panic(err)
	}
	if err := pp.postDecode(); err != nil {
		panic(err)
	}

	return pp
}

// Demangler maps symbol names to a human-readable form. This may
// include C++ demangling and additional simplification. Names that
// are not demangled may be missing from the resulting map.
type Demangler func(name []string) (map[string]string, error)

// Demangle attempts to demangle and optionally simplify any function
// names referenced in the profile. It works on a best-effort basis:
// it will silently preserve the original names in case of any errors.
func (p *Profile) Demangle(d Demangler) error {
	// Collect names to demangle.
	var names []string
	for _, fn := range p.Function {
		names = append(names, fn.SystemName)
	}

	// Update profile with demangled names.
	demangled, err := d(names)
	if err != nil {
		return err
	}
	for _, fn := range p.Function {
		if dd, ok := demangled[fn.SystemName]; ok {
			fn.Name = dd
		}
	}
	return nil
}

// Empty reports whether the profile contains no samples.
func (p *Profile) Empty() bool {
	return len(p.Sample) == 0
}

// Scale multiplies all sample values in a profile by a constant.
func (p *Profile) Scale(ratio float64) {
	if ratio == 1 {
		return
	}
	ratios := make([]float64, len(p.SampleType))
	for i := range p.SampleType {
		ratios[i] = ratio
	}
	p.ScaleN(ratios)
}

// ScaleN multiplies each sample values in a sample by a different amount.
func (p *Profile) ScaleN(ratios []float64) error {
	if len(p.SampleType) != len(ratios) {
		return fmt.Errorf("mismatched scale ratios, got %d, want %d", len(ratios), len(p.SampleType))
	}
	allOnes := true
	for _, r := range ratios {
		if r != 1 {
			allOnes = false
			break
		}
	}
	if allOnes {
		return nil
	}
	for _, s := range p.Sample {
		for i, v := range s.Value {
			if ratios[i] != 1 {
				s.Value[i] = int64(float64(v) * ratios[i])
			}
		}
	}
	return nil
}