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-rw-r--r--src/internal/profile/merge.go461
1 files changed, 461 insertions, 0 deletions
diff --git a/src/internal/profile/merge.go b/src/internal/profile/merge.go
new file mode 100644
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+++ b/src/internal/profile/merge.go
@@ -0,0 +1,461 @@
+// Copyright 2019 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
+
+import (
+ "fmt"
+ "sort"
+ "strconv"
+ "strings"
+)
+
+// Merge merges all the profiles in profs into a single Profile.
+// Returns a new profile independent of the input profiles. The merged
+// profile is compacted to eliminate unused samples, locations,
+// functions and mappings. Profiles must have identical profile sample
+// and period types or the merge will fail. profile.Period of the
+// resulting profile will be the maximum of all profiles, and
+// profile.TimeNanos will be the earliest nonzero one.
+func Merge(srcs []*Profile) (*Profile, error) {
+ if len(srcs) == 0 {
+ return nil, fmt.Errorf("no profiles to merge")
+ }
+ p, err := combineHeaders(srcs)
+ if err != nil {
+ return nil, err
+ }
+
+ pm := &profileMerger{
+ p: p,
+ samples: make(map[sampleKey]*Sample, len(srcs[0].Sample)),
+ locations: make(map[locationKey]*Location, len(srcs[0].Location)),
+ functions: make(map[functionKey]*Function, len(srcs[0].Function)),
+ mappings: make(map[mappingKey]*Mapping, len(srcs[0].Mapping)),
+ }
+
+ for _, src := range srcs {
+ // Clear the profile-specific hash tables
+ pm.locationsByID = make(map[uint64]*Location, len(src.Location))
+ pm.functionsByID = make(map[uint64]*Function, len(src.Function))
+ pm.mappingsByID = make(map[uint64]mapInfo, len(src.Mapping))
+
+ if len(pm.mappings) == 0 && len(src.Mapping) > 0 {
+ // The Mapping list has the property that the first mapping
+ // represents the main binary. Take the first Mapping we see,
+ // otherwise the operations below will add mappings in an
+ // arbitrary order.
+ pm.mapMapping(src.Mapping[0])
+ }
+
+ for _, s := range src.Sample {
+ if !isZeroSample(s) {
+ pm.mapSample(s)
+ }
+ }
+ }
+
+ for _, s := range p.Sample {
+ if isZeroSample(s) {
+ // If there are any zero samples, re-merge the profile to GC
+ // them.
+ return Merge([]*Profile{p})
+ }
+ }
+
+ return p, nil
+}
+
+// Normalize normalizes the source profile by multiplying each value in profile by the
+// ratio of the sum of the base profile's values of that sample type to the sum of the
+// source profile's value of that sample type.
+func (p *Profile) Normalize(pb *Profile) error {
+
+ if err := p.compatible(pb); err != nil {
+ return err
+ }
+
+ baseVals := make([]int64, len(p.SampleType))
+ for _, s := range pb.Sample {
+ for i, v := range s.Value {
+ baseVals[i] += v
+ }
+ }
+
+ srcVals := make([]int64, len(p.SampleType))
+ for _, s := range p.Sample {
+ for i, v := range s.Value {
+ srcVals[i] += v
+ }
+ }
+
+ normScale := make([]float64, len(baseVals))
+ for i := range baseVals {
+ if srcVals[i] == 0 {
+ normScale[i] = 0.0
+ } else {
+ normScale[i] = float64(baseVals[i]) / float64(srcVals[i])
+ }
+ }
+ p.ScaleN(normScale)
+ return nil
+}
+
+func isZeroSample(s *Sample) bool {
+ for _, v := range s.Value {
+ if v != 0 {
+ return false
+ }
+ }
+ return true
+}
+
+type profileMerger struct {
+ p *Profile
+
+ // Memoization tables within a profile.
+ locationsByID map[uint64]*Location
+ functionsByID map[uint64]*Function
+ mappingsByID map[uint64]mapInfo
+
+ // Memoization tables for profile entities.
+ samples map[sampleKey]*Sample
+ locations map[locationKey]*Location
+ functions map[functionKey]*Function
+ mappings map[mappingKey]*Mapping
+}
+
+type mapInfo struct {
+ m *Mapping
+ offset int64
+}
+
+func (pm *profileMerger) mapSample(src *Sample) *Sample {
+ s := &Sample{
+ Location: make([]*Location, len(src.Location)),
+ Value: make([]int64, len(src.Value)),
+ Label: make(map[string][]string, len(src.Label)),
+ NumLabel: make(map[string][]int64, len(src.NumLabel)),
+ NumUnit: make(map[string][]string, len(src.NumLabel)),
+ }
+ for i, l := range src.Location {
+ s.Location[i] = pm.mapLocation(l)
+ }
+ for k, v := range src.Label {
+ vv := make([]string, len(v))
+ copy(vv, v)
+ s.Label[k] = vv
+ }
+ for k, v := range src.NumLabel {
+ u := src.NumUnit[k]
+ vv := make([]int64, len(v))
+ uu := make([]string, len(u))
+ copy(vv, v)
+ copy(uu, u)
+ s.NumLabel[k] = vv
+ s.NumUnit[k] = uu
+ }
+ // Check memoization table. Must be done on the remapped location to
+ // account for the remapped mapping. Add current values to the
+ // existing sample.
+ k := s.key()
+ if ss, ok := pm.samples[k]; ok {
+ for i, v := range src.Value {
+ ss.Value[i] += v
+ }
+ return ss
+ }
+ copy(s.Value, src.Value)
+ pm.samples[k] = s
+ pm.p.Sample = append(pm.p.Sample, s)
+ return s
+}
+
+// key generates sampleKey to be used as a key for maps.
+func (sample *Sample) key() sampleKey {
+ ids := make([]string, len(sample.Location))
+ for i, l := range sample.Location {
+ ids[i] = strconv.FormatUint(l.ID, 16)
+ }
+
+ labels := make([]string, 0, len(sample.Label))
+ for k, v := range sample.Label {
+ labels = append(labels, fmt.Sprintf("%q%q", k, v))
+ }
+ sort.Strings(labels)
+
+ numlabels := make([]string, 0, len(sample.NumLabel))
+ for k, v := range sample.NumLabel {
+ numlabels = append(numlabels, fmt.Sprintf("%q%x%x", k, v, sample.NumUnit[k]))
+ }
+ sort.Strings(numlabels)
+
+ return sampleKey{
+ strings.Join(ids, "|"),
+ strings.Join(labels, ""),
+ strings.Join(numlabels, ""),
+ }
+}
+
+type sampleKey struct {
+ locations string
+ labels string
+ numlabels string
+}
+
+func (pm *profileMerger) mapLocation(src *Location) *Location {
+ if src == nil {
+ return nil
+ }
+
+ if l, ok := pm.locationsByID[src.ID]; ok {
+ pm.locationsByID[src.ID] = l
+ return l
+ }
+
+ mi := pm.mapMapping(src.Mapping)
+ l := &Location{
+ ID: uint64(len(pm.p.Location) + 1),
+ Mapping: mi.m,
+ Address: uint64(int64(src.Address) + mi.offset),
+ Line: make([]Line, len(src.Line)),
+ IsFolded: src.IsFolded,
+ }
+ for i, ln := range src.Line {
+ l.Line[i] = pm.mapLine(ln)
+ }
+ // Check memoization table. Must be done on the remapped location to
+ // account for the remapped mapping ID.
+ k := l.key()
+ if ll, ok := pm.locations[k]; ok {
+ pm.locationsByID[src.ID] = ll
+ return ll
+ }
+ pm.locationsByID[src.ID] = l
+ pm.locations[k] = l
+ pm.p.Location = append(pm.p.Location, l)
+ return l
+}
+
+// key generates locationKey to be used as a key for maps.
+func (l *Location) key() locationKey {
+ key := locationKey{
+ addr: l.Address,
+ isFolded: l.IsFolded,
+ }
+ if l.Mapping != nil {
+ // Normalizes address to handle address space randomization.
+ key.addr -= l.Mapping.Start
+ key.mappingID = l.Mapping.ID
+ }
+ lines := make([]string, len(l.Line)*2)
+ for i, line := range l.Line {
+ if line.Function != nil {
+ lines[i*2] = strconv.FormatUint(line.Function.ID, 16)
+ }
+ lines[i*2+1] = strconv.FormatInt(line.Line, 16)
+ }
+ key.lines = strings.Join(lines, "|")
+ return key
+}
+
+type locationKey struct {
+ addr, mappingID uint64
+ lines string
+ isFolded bool
+}
+
+func (pm *profileMerger) mapMapping(src *Mapping) mapInfo {
+ if src == nil {
+ return mapInfo{}
+ }
+
+ if mi, ok := pm.mappingsByID[src.ID]; ok {
+ return mi
+ }
+
+ // Check memoization tables.
+ mk := src.key()
+ if m, ok := pm.mappings[mk]; ok {
+ mi := mapInfo{m, int64(m.Start) - int64(src.Start)}
+ pm.mappingsByID[src.ID] = mi
+ return mi
+ }
+ m := &Mapping{
+ ID: uint64(len(pm.p.Mapping) + 1),
+ Start: src.Start,
+ Limit: src.Limit,
+ Offset: src.Offset,
+ File: src.File,
+ BuildID: src.BuildID,
+ HasFunctions: src.HasFunctions,
+ HasFilenames: src.HasFilenames,
+ HasLineNumbers: src.HasLineNumbers,
+ HasInlineFrames: src.HasInlineFrames,
+ }
+ pm.p.Mapping = append(pm.p.Mapping, m)
+
+ // Update memoization tables.
+ pm.mappings[mk] = m
+ mi := mapInfo{m, 0}
+ pm.mappingsByID[src.ID] = mi
+ return mi
+}
+
+// key generates encoded strings of Mapping to be used as a key for
+// maps.
+func (m *Mapping) key() mappingKey {
+ // Normalize addresses to handle address space randomization.
+ // Round up to next 4K boundary to avoid minor discrepancies.
+ const mapsizeRounding = 0x1000
+
+ size := m.Limit - m.Start
+ size = size + mapsizeRounding - 1
+ size = size - (size % mapsizeRounding)
+ key := mappingKey{
+ size: size,
+ offset: m.Offset,
+ }
+
+ switch {
+ case m.BuildID != "":
+ key.buildIDOrFile = m.BuildID
+ case m.File != "":
+ key.buildIDOrFile = m.File
+ default:
+ // A mapping containing neither build ID nor file name is a fake mapping. A
+ // key with empty buildIDOrFile is used for fake mappings so that they are
+ // treated as the same mapping during merging.
+ }
+ return key
+}
+
+type mappingKey struct {
+ size, offset uint64
+ buildIDOrFile string
+}
+
+func (pm *profileMerger) mapLine(src Line) Line {
+ ln := Line{
+ Function: pm.mapFunction(src.Function),
+ Line: src.Line,
+ }
+ return ln
+}
+
+func (pm *profileMerger) mapFunction(src *Function) *Function {
+ if src == nil {
+ return nil
+ }
+ if f, ok := pm.functionsByID[src.ID]; ok {
+ return f
+ }
+ k := src.key()
+ if f, ok := pm.functions[k]; ok {
+ pm.functionsByID[src.ID] = f
+ return f
+ }
+ f := &Function{
+ ID: uint64(len(pm.p.Function) + 1),
+ Name: src.Name,
+ SystemName: src.SystemName,
+ Filename: src.Filename,
+ StartLine: src.StartLine,
+ }
+ pm.functions[k] = f
+ pm.functionsByID[src.ID] = f
+ pm.p.Function = append(pm.p.Function, f)
+ return f
+}
+
+// key generates a struct to be used as a key for maps.
+func (f *Function) key() functionKey {
+ return functionKey{
+ f.StartLine,
+ f.Name,
+ f.SystemName,
+ f.Filename,
+ }
+}
+
+type functionKey struct {
+ startLine int64
+ name, systemName, fileName string
+}
+
+// combineHeaders checks that all profiles can be merged and returns
+// their combined profile.
+func combineHeaders(srcs []*Profile) (*Profile, error) {
+ for _, s := range srcs[1:] {
+ if err := srcs[0].compatible(s); err != nil {
+ return nil, err
+ }
+ }
+
+ var timeNanos, durationNanos, period int64
+ var comments []string
+ seenComments := map[string]bool{}
+ var defaultSampleType string
+ for _, s := range srcs {
+ if timeNanos == 0 || s.TimeNanos < timeNanos {
+ timeNanos = s.TimeNanos
+ }
+ durationNanos += s.DurationNanos
+ if period == 0 || period < s.Period {
+ period = s.Period
+ }
+ for _, c := range s.Comments {
+ if seen := seenComments[c]; !seen {
+ comments = append(comments, c)
+ seenComments[c] = true
+ }
+ }
+ if defaultSampleType == "" {
+ defaultSampleType = s.DefaultSampleType
+ }
+ }
+
+ p := &Profile{
+ SampleType: make([]*ValueType, len(srcs[0].SampleType)),
+
+ DropFrames: srcs[0].DropFrames,
+ KeepFrames: srcs[0].KeepFrames,
+
+ TimeNanos: timeNanos,
+ DurationNanos: durationNanos,
+ PeriodType: srcs[0].PeriodType,
+ Period: period,
+
+ Comments: comments,
+ DefaultSampleType: defaultSampleType,
+ }
+ copy(p.SampleType, srcs[0].SampleType)
+ return p, nil
+}
+
+// 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 !equalValueType(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 !equalValueType(p.SampleType[i], pb.SampleType[i]) {
+ return fmt.Errorf("incompatible sample types %v and %v", p.SampleType, pb.SampleType)
+ }
+ }
+ return nil
+}
+
+// equalValueType returns true if the two value types are semantically
+// equal. It ignores the internal fields used during encode/decode.
+func equalValueType(st1, st2 *ValueType) bool {
+ return st1.Type == st2.Type && st1.Unit == st2.Unit
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-03 21:26:34 +0000