// Copyright 2014 Google Inc. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// This file implements parsers to convert legacy profiles into the
// profile.proto format.
package profile
import (
"bufio"
"bytes"
"fmt"
"io"
"math"
"regexp"
"strconv"
"strings"
)
var (
countStartRE = regexp.MustCompile(`\A(\S+) profile: total \d+\z`)
countRE = regexp.MustCompile(`\A(\d+) @(( 0x[0-9a-f]+)+)\z`)
heapHeaderRE = regexp.MustCompile(`heap profile: *(\d+): *(\d+) *\[ *(\d+): *(\d+) *\] *@ *(heap[_a-z0-9]*)/?(\d*)`)
heapSampleRE = regexp.MustCompile(`(-?\d+): *(-?\d+) *\[ *(\d+): *(\d+) *] @([ x0-9a-f]*)`)
contentionSampleRE = regexp.MustCompile(`(\d+) *(\d+) @([ x0-9a-f]*)`)
hexNumberRE = regexp.MustCompile(`0x[0-9a-f]+`)
growthHeaderRE = regexp.MustCompile(`heap profile: *(\d+): *(\d+) *\[ *(\d+): *(\d+) *\] @ growthz?`)
fragmentationHeaderRE = regexp.MustCompile(`heap profile: *(\d+): *(\d+) *\[ *(\d+): *(\d+) *\] @ fragmentationz?`)
threadzStartRE = regexp.MustCompile(`--- threadz \d+ ---`)
threadStartRE = regexp.MustCompile(`--- Thread ([[:xdigit:]]+) \(name: (.*)/(\d+)\) stack: ---`)
// Regular expressions to parse process mappings. Support the format used by Linux /proc/.../maps and other tools.
// Recommended format:
// Start End object file name offset(optional) linker build id
// 0x40000-0x80000 /path/to/binary (@FF00) abc123456
spaceDigits = `\s+[[:digit:]]+`
hexPair = `\s+[[:xdigit:]]+:[[:xdigit:]]+`
oSpace = `\s*`
// Capturing expressions.
cHex = `(?:0x)?([[:xdigit:]]+)`
cHexRange = `\s*` + cHex + `[\s-]?` + oSpace + cHex + `:?`
cSpaceString = `(?:\s+(\S+))?`
cSpaceHex = `(?:\s+([[:xdigit:]]+))?`
cSpaceAtOffset = `(?:\s+\(@([[:xdigit:]]+)\))?`
cPerm = `(?:\s+([-rwxp]+))?`
procMapsRE = regexp.MustCompile(`^` + cHexRange + cPerm + cSpaceHex + hexPair + spaceDigits + cSpaceString)
briefMapsRE = regexp.MustCompile(`^` + cHexRange + cPerm + cSpaceString + cSpaceAtOffset + cSpaceHex)
// Regular expression to parse log data, of the form:
// ... file:line] msg...
logInfoRE = regexp.MustCompile(`^[^\[\]]+:[0-9]+]\s`)
)
func isSpaceOrComment(line string) bool {
trimmed := strings.TrimSpace(line)
return len(trimmed) == 0 || trimmed[0] == '#'
}
// parseGoCount parses a Go count profile (e.g., threadcreate or
// goroutine) and returns a new Profile.
func parseGoCount(b []byte) (*Profile, error) {
s := bufio.NewScanner(bytes.NewBuffer(b))
// Skip comments at the beginning of the file.
for s.Scan() && isSpaceOrComment(s.Text()) {
}
if err := s.Err(); err != nil {
return nil, err
}
m := countStartRE.FindStringSubmatch(s.Text())
if m == nil {
return nil, errUnrecognized
}
profileType := m[1]
p := &Profile{
PeriodType: &ValueType{Type: profileType, Unit: "count"},
Period: 1,
SampleType: []*ValueType{{Type: profileType, Unit: "count"}},
}
locations := make(map[uint64]*Location)
for s.Scan() {
line := s.Text()
if isSpaceOrComment(line) {
continue
}
if strings.HasPrefix(line, "---") {
break
}
m := countRE.FindStringSubmatch(line)
if m == nil {
return nil, errMalformed
}
n, err := strconv.ParseInt(m[1], 0, 64)
if err != nil {
return nil, errMalformed
}
fields := strings.Fields(m[2])
locs := make([]*Location, 0, len(fields))
for _, stk := range fields {
addr, err := strconv.ParseUint(stk, 0, 64)
if err != nil {
return nil, errMalformed
}
// Adjust all frames by -1 to land on top of the call instruction.
addr--
loc := locations[addr]
if loc == nil {
loc = &Location{
Address: addr,
}
locations[addr] = loc
p.Location = append(p.Location, loc)
}
locs = append(locs, loc)
}
p.Sample = append(p.Sample, &Sample{
Location: locs,
Value: []int64{n},
})
}
if err := s.Err(); err != nil {
return nil, err
}
if err := parseAdditionalSections(s, p); err != nil {
return nil, err
}
return p, nil
}
// remapLocationIDs ensures there is a location for each address
// referenced by a sample, and remaps the samples to point to the new
// location ids.
func (p *Profile) remapLocationIDs() {
seen := make(map[*Location]bool, len(p.Location))
var locs []*Location
for _, s := range p.Sample {
for _, l := range s.Location {
if seen[l] {
continue
}
l.ID = uint64(len(locs) + 1)
locs = append(locs, l)
seen[l] = true
}
}
p.Location = locs
}
func (p *Profile) remapFunctionIDs() {
seen := make(map[*Function]bool, len(p.Function))
var fns []*Function
for _, l := range p.Location {
for _, ln := range l.Line {
fn := ln.Function
if fn == nil || seen[fn] {
continue
}
fn.ID = uint64(len(fns) + 1)
fns = append(fns, fn)
seen[fn] = true
}
}
p.Function = fns
}
// remapMappingIDs matches location addresses with existing mappings
// and updates them appropriately. This is O(N*M), if this ever shows
// up as a bottleneck, evaluate sorting the mappings and doing a
// binary search, which would make it O(N*log(M)).
func (p *Profile) remapMappingIDs() {
// Some profile handlers will incorrectly set regions for the main
// executable if its section is remapped. Fix them through heuristics.
if len(p.Mapping) > 0 {
// Remove the initial mapping if named '/anon_hugepage' and has a
// consecutive adjacent mapping.
if m := p.Mapping[0]; strings.HasPrefix(m.File, "/anon_hugepage") {
if len(p.Mapping) > 1 && m.Limit == p.Mapping[1].Start {
p.Mapping = p.Mapping[1:]
}
}
}
// Subtract the offset from the start of the main mapping if it
// ends up at a recognizable start address.
if len(p.Mapping) > 0 {
const expectedStart = 0x400000
if m := p.Mapping[0]; m.Start-m.Offset == expectedStart {
m.Start = expectedStart
m.Offset = 0
}
}
// Associate each location with an address to the corresponding
// mapping. Create fake mapping if a suitable one isn't found.
var fake *Mapping
nextLocation:
for _, l := range p.Location {
a := l.Address
if l.Mapping != nil || a == 0 {
continue
}
for _, m := range p.Mapping {
if m.Start <= a && a < m.Limit {
l.Mapping = m
continue nextLocation
}
}
// Work around legacy handlers failing to encode the first
// part of mappings split into adjacent ranges.
for _, m := range p.Mapping {
if m.Offset != 0 && m.Start-m.Offset <= a && a < m.Start {
m.Start -= m.Offset
m.Offset = 0
l.Mapping = m
continue nextLocation
}
}
// If there is still no mapping, create a fake one.
// This is important for the Go legacy handler, which produced
// no mappings.
if fake == nil {
fake = &Mapping{
ID: 1,
Limit: ^uint64(0),
}
p.Mapping = append(p.Mapping, fake)
}
l.Mapping = fake
}
// Reset all mapping IDs.
for i, m := range p.Mapping {
m.ID = uint64(i + 1)
}
}
var cpuInts = []func([]byte) (uint64, []byte){
get32l,
get32b,
get64l,
get64b,
}
func get32l(b []byte) (uint64, []byte) {
if len(b) < 4 {
return 0, nil
}
return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24, b[4:]
}
func get32b(b []byte) (uint64, []byte) {
if len(b) < 4 {
return 0, nil
}
return uint64(b[3]) | uint64(b[2])<<8 | uint64(b[1])<<16 | uint64(b[0])<<24, b[4:]
}
func get64l(b []byte) (uint64, []byte) {
if len(b) < 8 {
return 0, nil
}
return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56, b[8:]
}
func get64b(b []byte) (uint64, []byte) {
if len(b) < 8 {
return 0, nil
}
return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 | uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56, b[8:]
}
// parseCPU parses a profilez legacy profile and returns a newly
// populated Profile.
//
// The general format for profilez samples is a sequence of words in
// binary format. The first words are a header with the following data:
//
// 1st word -- 0
// 2nd word -- 3
// 3rd word -- 0 if a c++ application, 1 if a java application.
// 4th word -- Sampling period (in microseconds).
// 5th word -- Padding.
func parseCPU(b []byte) (*Profile, error) {
var parse func([]byte) (uint64, []byte)
var n1, n2, n3, n4, n5 uint64
for _, parse = range cpuInts {
var tmp []byte
n1, tmp = parse(b)
n2, tmp = parse(tmp)
n3, tmp = parse(tmp)
n4, tmp = parse(tmp)
n5, tmp = parse(tmp)
if tmp != nil && n1 == 0 && n2 == 3 && n3 == 0 && n4 > 0 && n5 == 0 {
b = tmp
return cpuProfile(b, int64(n4), parse)
}
if tmp != nil && n1 == 0 && n2 == 3 && n3 == 1 && n4 > 0 && n5 == 0 {
b = tmp
return javaCPUProfile(b, int64(n4), parse)
}
}
return nil, errUnrecognized
}
// cpuProfile returns a new Profile from C++ profilez data.
// b is the profile bytes after the header, period is the profiling
// period, and parse is a function to parse 8-byte chunks from the
// profile in its native endianness.
func cpuProfile(b []byte, period int64, parse func(b []byte) (uint64, []byte)) (*Profile, error) {
p := &Profile{
Period: period * 1000,
PeriodType: &ValueType{Type: "cpu", Unit: "nanoseconds"},
SampleType: []*ValueType{
{Type: "samples", Unit: "count"},
{Type: "cpu", Unit: "nanoseconds"},
},
}
var err error
if b, _, err = parseCPUSamples(b, parse, true, p); err != nil {
return nil, err
}
// If *most* samples have the same second-to-the-bottom frame, it
// strongly suggests that it is an uninteresting artifact of
// measurement -- a stack frame pushed by the signal handler. The
// bottom frame is always correct as it is picked up from the signal
// structure, not the stack. Check if this is the case and if so,
// remove.
// Remove up to two frames.
maxiter := 2
// Allow one different sample for this many samples with the same
// second-to-last frame.
similarSamples := 32
margin := len(p.Sample) / similarSamples
for iter := 0; iter < maxiter; iter++ {
addr1 := make(map[uint64]int)
for _, s := range p.Sample {
if len(s.Location) > 1 {
a := s.Location[1].Address
addr1[a] = addr1[a] + 1
}
}
for id1, count := range addr1 {
if count >= len(p.Sample)-margin {
// Found uninteresting frame, strip it out from all samples
for _, s := range p.Sample {
if len(s.Location) > 1 && s.Location[1].Address == id1 {
s.Location = append(s.Location[:1], s.Location[2:]...)
}
}
break
}
}
}
if err := p.ParseMemoryMap(bytes.NewBuffer(b)); err != nil {
return nil, err
}
cleanupDuplicateLocations(p)
return p, nil
}
func cleanupDuplicateLocations(p *Profile) {
// The profile handler may duplicate the leaf frame, because it gets
// its address both from stack unwinding and from the signal
// context. Detect this and delete the duplicate, which has been
// adjusted by -1. The leaf address should not be adjusted as it is
// not a call.
for _, s := range p.Sample {
if len(s.Location) > 1 && s.Location[0].Address == s.Location[1].Address+1 {
s.Location = append(s.Location[:1], s.Location[2:]...)
}
}
}
// parseCPUSamples parses a collection of profilez samples from a
// profile.
//
// profilez samples are a repeated sequence of stack frames of the
// form:
//
// 1st word -- The number of times this stack was encountered.
// 2nd word -- The size of the stack (StackSize).
// 3rd word -- The first address on the stack.
// ...
// StackSize + 2 -- The last address on the stack
//
// The last stack trace is of the form:
//
// 1st word -- 0
// 2nd word -- 1
// 3rd word -- 0
//
// Addresses from stack traces may point to the next instruction after
// each call. Optionally adjust by -1 to land somewhere on the actual
// call (except for the leaf, which is not a call).
func parseCPUSamples(b []byte, parse func(b []byte) (uint64, []byte), adjust bool, p *Profile) ([]byte, map[uint64]*Location, error) {
locs := make(map[uint64]*Location)
for len(b) > 0 {
var count, nstk uint64
count, b = parse(b)
nstk, b = parse(b)
if b == nil || nstk > uint64(len(b)/4) {
return nil, nil, errUnrecognized
}
var sloc []*Location
addrs := make([]uint64, nstk)
for i := 0; i < int(nstk); i++ {
addrs[i], b = parse(b)
}
if count == 0 && nstk == 1 && addrs[0] == 0 {
// End of data marker
break
}
for i, addr := range addrs {
if adjust && i > 0 {
addr--
}
loc := locs[addr]
if loc == nil {
loc = &Location{
Address: addr,
}
locs[addr] = loc
p.Location = append(p.Location, loc)
}
sloc = append(sloc, loc)
}
p.Sample = append(p.Sample,
&Sample{
Value: []int64{int64(count), int64(count) * p.Period},
Location: sloc,
})
}
// Reached the end without finding the EOD marker.
return b, locs, nil
}
// parseHeap parses a heapz legacy or a growthz profile and
// returns a newly populated Profile.
func parseHeap(b []byte) (p *Profile, err error) {
s := bufio.NewScanner(bytes.NewBuffer(b))
if !s.Scan() {
if err := s.Err(); err != nil {
return nil, err
}
return nil, errUnrecognized
}
p = &Profile{}
sampling := ""
hasAlloc := false
line := s.Text()
p.PeriodType = &ValueType{Type: "space", Unit: "bytes"}
if header := heapHeaderRE.FindStringSubmatch(line); header != nil {
sampling, p.Period, hasAlloc, err = parseHeapHeader(line)
if err != nil {
return nil, err
}
} else if header = growthHeaderRE.FindStringSubmatch(line); header != nil {
p.Period = 1
} else if header = fragmentationHeaderRE.FindStringSubmatch(line); header != nil {
p.Period = 1
} else {
return nil, errUnrecognized
}
if hasAlloc {
// Put alloc before inuse so that default pprof selection
// will prefer inuse_space.
p.SampleType = []*ValueType{
{Type: "alloc_objects", Unit: "count"},
{Type: "alloc_space", Unit: "bytes"},
{Type: "inuse_objects", Unit: "count"},
{Type: "inuse_space", Unit: "bytes"},
}
} else {
p.SampleType = []*ValueType{
{Type: "objects", Unit: "count"},
{Type: "space", Unit: "bytes"},
}
}
locs := make(map[uint64]*Location)
for s.Scan() {
line := strings.TrimSpace(s.Text())
if isSpaceOrComment(line) {
continue
}
if isMemoryMapSentinel(line) {
break
}
value, blocksize, addrs, err := parseHeapSample(line, p.Period, sampling, hasAlloc)
if err != nil {
return nil, err
}
var sloc []*Location
for _, addr := range addrs {
// Addresses from stack traces point to the next instruction after
// each call. Adjust by -1 to land somewhere on the actual call.
addr--
loc := locs[addr]
if locs[addr] == nil {
loc = &Location{
Address: addr,
}
p.Location = append(p.Location, loc)
locs[addr] = loc
}
sloc = append(sloc, loc)
}
p.Sample = append(p.Sample, &Sample{
Value: value,
Location: sloc,
NumLabel: map[string][]int64{"bytes": {blocksize}},
})
}
if err := s.Err(); err != nil {
return nil, err
}
if err := parseAdditionalSections(s, p); err != nil {
return nil, err
}
return p, nil
}
func parseHeapHeader(line string) (sampling string, period int64, hasAlloc bool, err error) {
header := heapHeaderRE.FindStringSubmatch(line)
if header == nil {
return "", 0, false, errUnrecognized
}
if len(header[6]) > 0 {
if period, err = strconv.ParseInt(header[6], 10, 64); err != nil {
return "", 0, false, errUnrecognized
}
}
if (header[3] != header[1] && header[3] != "0") || (header[4] != header[2] && header[4] != "0") {
hasAlloc = true
}
switch header[5] {
case "heapz_v2", "heap_v2":
return "v2", period, hasAlloc, nil
case "heapprofile":
return "", 1, hasAlloc, nil
case "heap":
return "v2", period / 2, hasAlloc, nil
default:
return "", 0, false, errUnrecognized
}
}
// parseHeapSample parses a single row from a heap profile into a new Sample.
func parseHeapSample(line string, rate int64, sampling string, includeAlloc bool) (value []int64, blocksize int64, addrs []uint64, err error) {
sampleData := heapSampleRE.FindStringSubmatch(line)
if len(sampleData) != 6 {
return nil, 0, nil, fmt.Errorf("unexpected number of sample values: got %d, want 6", len(sampleData))
}
// This is a local-scoped helper function to avoid needing to pass
// around rate, sampling and many return parameters.
addValues := func(countString, sizeString string, label string) error {
count, err := strconv.ParseInt(countString, 10, 64)
if err != nil {
return fmt.Errorf("malformed sample: %s: %v", line, err)
}
size, err := strconv.ParseInt(sizeString, 10, 64)
if err != nil {
return fmt.Errorf("malformed sample: %s: %v", line, err)
}
if count == 0 && size != 0 {
return fmt.Errorf("%s count was 0 but %s bytes was %d", label, label, size)
}
if count != 0 {
blocksize = size / count
if sampling == "v2" {
count, size = scaleHeapSample(count, size, rate)
}
}
value = append(value, count, size)
return nil
}
if includeAlloc {
if err := addValues(sampleData[3], sampleData[4], "allocation"); err != nil {
return nil, 0, nil, err
}
}
if err := addValues(sampleData[1], sampleData[2], "inuse"); err != nil {
return nil, 0, nil, err
}
addrs, err = parseHexAddresses(sampleData[5])
if err != nil {
return nil, 0, nil, fmt.Errorf("malformed sample: %s: %v", line, err)
}
return value, blocksize, addrs, nil
}
// parseHexAddresses extracts hex numbers from a string, attempts to convert
// each to an unsigned 64-bit number and returns the resulting numbers as a
// slice, or an error if the string contains hex numbers which are too large to
// handle (which means a malformed profile).
func parseHexAddresses(s string) ([]uint64, error) {
hexStrings := hexNumberRE.FindAllString(s, -1)
var addrs []uint64
for _, s := range hexStrings {
if addr, err := strconv.ParseUint(s, 0, 64); err == nil {
addrs = append(addrs, addr)
} else {
return nil, fmt.Errorf("failed to parse as hex 64-bit number: %s", s)
}
}
return addrs, nil
}
// scaleHeapSample adjusts the data from a heapz Sample to
// account for its probability of appearing in the collected
// data. heapz profiles are a sampling of the memory allocations
// requests in a program. We estimate the unsampled value by dividing
// each collected sample by its probability of appearing in the
// profile. heapz v2 profiles rely on a poisson process to determine
// which samples to collect, based on the desired average collection
// rate R. The probability of a sample of size S to appear in that
// profile is 1-exp(-S/R).
func scaleHeapSample(count, size, rate int64) (int64, int64) {
if count == 0 || size == 0 {
return 0, 0
}
if rate <= 1 {
// if rate==1 all samples were collected so no adjustment is needed.
// if rate<1 treat as unknown and skip scaling.
return count, size
}
avgSize := float64(size) / float64(count)
scale := 1 / (1 - math.Exp(-avgSize/float64(rate)))
return int64(float64(count) * scale), int64(float64(size) * scale)
}
// parseContention parses a mutex or contention profile. There are 2 cases:
// "--- contentionz " for legacy C++ profiles (and backwards compatibility)
// "--- mutex:" or "--- contention:" for profiles generated by the Go runtime.
func parseContention(b []byte) (*Profile, error) {
s := bufio.NewScanner(bytes.NewBuffer(b))
if !s.Scan() {
if err := s.Err(); err != nil {
return nil, err
}
return nil, errUnrecognized
}
switch l := s.Text(); {
case strings.HasPrefix(l, "--- contentionz "):
case strings.HasPrefix(l, "--- mutex:"):
case strings.HasPrefix(l, "--- contention:"):
default:
return nil, errUnrecognized
}
p := &Profile{
PeriodType: &ValueType{Type: "contentions", Unit: "count"},
Period: 1,
SampleType: []*ValueType{
{Type: "contentions", Unit: "count"},
{Type: "delay", Unit: "nanoseconds"},
},
}
var cpuHz int64
// Parse text of the form "attribute = value" before the samples.
const delimiter = "="
for s.Scan() {
line := s.Text()
if line = strings.TrimSpace(line); isSpaceOrComment(line) {
continue
}
if strings.HasPrefix(line, "---") {
break
}
attr := strings.SplitN(line, delimiter, 2)
if len(attr) != 2 {
break
}
key, val := strings.TrimSpace(attr[0]), strings.TrimSpace(attr[1])
var err error
switch key {
case "cycles/second":
if cpuHz, err = strconv.ParseInt(val, 0, 64); err != nil {
return nil, errUnrecognized
}
case "sampling period":
if p.Period, err = strconv.ParseInt(val, 0, 64); err != nil {
return nil, errUnrecognized
}
case "ms since reset":
ms, err := strconv.ParseInt(val, 0, 64)
if err != nil {
return nil, errUnrecognized
}
p.DurationNanos = ms * 1000 * 1000
case "format":
// CPP contentionz profiles don't have format.
return nil, errUnrecognized
case "resolution":
// CPP contentionz profiles don't have resolution.
return nil, errUnrecognized
case "discarded samples":
default:
return nil, errUnrecognized
}
}
if err := s.Err(); err != nil {
return nil, err
}
locs := make(map[uint64]*Location)
for {
line := strings.TrimSpace(s.Text())
if strings.HasPrefix(line, "---") {
break
}
if !isSpaceOrComment(line) {
value, addrs, err := parseContentionSample(line, p.Period, cpuHz)
if err != nil {
return nil, err
}
var sloc []*Location
for _, addr := range addrs {
// Addresses from stack traces point to the next instruction after
// each call. Adjust by -1 to land somewhere on the actual call.
addr--
loc := locs[addr]
if locs[addr] == nil {
loc = &Location{
Address: addr,
}
p.Location = append(p.Location, loc)
locs[addr] = loc
}
sloc = append(sloc, loc)
}
p.Sample = append(p.Sample, &Sample{
Value: value,
Location: sloc,
})
}
if !s.Scan() {
break
}
}
if err := s.Err(); err != nil {
return nil, err
}
if err := parseAdditionalSections(s, p); err != nil {
return nil, err
}
return p, nil
}
// parseContentionSample parses a single row from a contention profile
// into a new Sample.
func parseContentionSample(line string, period, cpuHz int64) (value []int64, addrs []uint64, err error) {
sampleData := contentionSampleRE.FindStringSubmatch(line)
if sampleData == nil {
return nil, nil, errUnrecognized
}
v1, err := strconv.ParseInt(sampleData[1], 10, 64)
if err != nil {
return nil, nil, fmt.Errorf("malformed sample: %s: %v", line, err)
}
v2, err := strconv.ParseInt(sampleData[2], 10, 64)
if err != nil {
return nil, nil, fmt.Errorf("malformed sample: %s: %v", line, err)
}
// Unsample values if period and cpuHz are available.
// - Delays are scaled to cycles and then to nanoseconds.
// - Contentions are scaled to cycles.
if period > 0 {
if cpuHz > 0 {
cpuGHz := float64(cpuHz) / 1e9
v1 = int64(float64(v1) * float64(period) / cpuGHz)
}
v2 = v2 * period
}
value = []int64{v2, v1}
addrs, err = parseHexAddresses(sampleData[3])
if err != nil {
return nil, nil, fmt.Errorf("malformed sample: %s: %v", line, err)
}
return value, addrs, nil
}
// parseThread parses a Threadz profile and returns a new Profile.
func parseThread(b []byte) (*Profile, error) {
s := bufio.NewScanner(bytes.NewBuffer(b))
// Skip past comments and empty lines seeking a real header.
for s.Scan() && isSpaceOrComment(s.Text()) {
}
line := s.Text()
if m := threadzStartRE.FindStringSubmatch(line); m != nil {
// Advance over initial comments until first stack trace.
for s.Scan() {
if line = s.Text(); isMemoryMapSentinel(line) || strings.HasPrefix(line, "-") {
break
}
}
} else if t := threadStartRE.FindStringSubmatch(line); len(t) != 4 {
return nil, errUnrecognized
}
p := &Profile{
SampleType: []*ValueType{{Type: "thread", Unit: "count"}},
PeriodType: &ValueType{Type: "thread", Unit: "count"},
Period: 1,
}
locs := make(map[uint64]*Location)
// Recognize each thread and populate profile samples.
for !isMemoryMapSentinel(line) {
if strings.HasPrefix(line, "---- no stack trace for") {
break
}
if t := threadStartRE.FindStringSubmatch(line); len(t) != 4 {
return nil, errUnrecognized
}
var addrs []uint64
var err error
line, addrs, err = parseThreadSample(s)
if err != nil {
return nil, err
}
if len(addrs) == 0 {
// We got a --same as previous threads--. Bump counters.
if len(p.Sample) > 0 {
s := p.Sample[len(p.Sample)-1]
s.Value[0]++
}
continue
}
var sloc []*Location
for i, addr := range addrs {
// Addresses from stack traces point to the next instruction after
// each call. Adjust by -1 to land somewhere on the actual call
// (except for the leaf, which is not a call).
if i > 0 {
addr--
}
loc := locs[addr]
if locs[addr] == nil {
loc = &Location{
Address: addr,
}
p.Location = append(p.Location, loc)
locs[addr] = loc
}
sloc = append(sloc, loc)
}
p.Sample = append(p.Sample, &Sample{
Value: []int64{1},
Location: sloc,
})
}
if err := parseAdditionalSections(s, p); err != nil {
return nil, err
}
cleanupDuplicateLocations(p)
return p, nil
}
// parseThreadSample parses a symbolized or unsymbolized stack trace.
// Returns the first line after the traceback, the sample (or nil if
// it hits a 'same-as-previous' marker) and an error.
func parseThreadSample(s *bufio.Scanner) (nextl string, addrs []uint64, err error) {
var line string
sameAsPrevious := false
for s.Scan() {
line = strings.TrimSpace(s.Text())
if line == "" {
continue
}
if strings.HasPrefix(line, "---") {
break
}
if strings.Contains(line, "same as previous thread") {
sameAsPrevious = true
continue
}
curAddrs, err := parseHexAddresses(line)
if err != nil {
return "", nil, fmt.Errorf("malformed sample: %s: %v", line, err)
}
addrs = append(addrs, curAddrs...)
}
if err := s.Err(); err != nil {
return "", nil, err
}
if sameAsPrevious {
return line, nil, nil
}
return line, addrs, nil
}
// parseAdditionalSections parses any additional sections in the
// profile, ignoring any unrecognized sections.
func parseAdditionalSections(s *bufio.Scanner, p *Profile) error {
for !isMemoryMapSentinel(s.Text()) && s.Scan() {
}
if err := s.Err(); err != nil {
return err
}
return p.ParseMemoryMapFromScanner(s)
}
// ParseProcMaps parses a memory map in the format of /proc/self/maps.
// ParseMemoryMap should be called after setting on a profile to
// associate locations to the corresponding mapping based on their
// address.
func ParseProcMaps(rd io.Reader) ([]*Mapping, error) {
s := bufio.NewScanner(rd)
return parseProcMapsFromScanner(s)
}
func parseProcMapsFromScanner(s *bufio.Scanner) ([]*Mapping, error) {
var mapping []*Mapping
var attrs []string
const delimiter = "="
r := strings.NewReplacer()
for s.Scan() {
line := r.Replace(removeLoggingInfo(s.Text()))
m, err := parseMappingEntry(line)
if err != nil {
if err == errUnrecognized {
// Recognize assignments of the form: attr=value, and replace
// $attr with value on subsequent mappings.
if attr := strings.SplitN(line, delimiter, 2); len(attr) == 2 {
attrs = append(attrs, "$"+strings.TrimSpace(attr[0]), strings.TrimSpace(attr[1]))
r = strings.NewReplacer(attrs...)
}
// Ignore any unrecognized entries
continue
}
return nil, err
}
if m == nil {
continue
}
mapping = append(mapping, m)
}
if err := s.Err(); err != nil {
return nil, err
}
return mapping, nil
}
// removeLoggingInfo detects and removes log prefix entries generated
// by the glog package. If no logging prefix is detected, the string
// is returned unmodified.
func removeLoggingInfo(line string) string {
if match := logInfoRE.FindStringIndex(line); match != nil {
return line[match[1]:]
}
return line
}
// ParseMemoryMap parses a memory map in the format of
// /proc/self/maps, and overrides the mappings in the current profile.
// It renumbers the samples and locations in the profile correspondingly.
func (p *Profile) ParseMemoryMap(rd io.Reader) error {
return p.ParseMemoryMapFromScanner(bufio.NewScanner(rd))
}
// ParseMemoryMapFromScanner parses a memory map in the format of
// /proc/self/maps or a variety of legacy format, and overrides the
// mappings in the current profile. It renumbers the samples and
// locations in the profile correspondingly.
func (p *Profile) ParseMemoryMapFromScanner(s *bufio.Scanner) error {
mapping, err := parseProcMapsFromScanner(s)
if err != nil {
return err
}
p.Mapping = append(p.Mapping, mapping...)
p.massageMappings()
p.remapLocationIDs()
p.remapFunctionIDs()
p.remapMappingIDs()
return nil
}
func parseMappingEntry(l string) (*Mapping, error) {
var start, end, perm, file, offset, buildID string
if me := procMapsRE.FindStringSubmatch(l); len(me) == 6 {
start, end, perm, offset, file = me[1], me[2], me[3], me[4], me[5]
} else if me := briefMapsRE.FindStringSubmatch(l); len(me) == 7 {
start, end, perm, file, offset, buildID = me[1], me[2], me[3], me[4], me[5], me[6]
} else {
return nil, errUnrecognized
}
var err error
mapping := &Mapping{
File: file,
BuildID: buildID,
}
if perm != "" && !strings.Contains(perm, "x") {
// Skip non-executable entries.
return nil, nil
}
if mapping.Start, err = strconv.ParseUint(start, 16, 64); err != nil {
return nil, errUnrecognized
}
if mapping.Limit, err = strconv.ParseUint(end, 16, 64); err != nil {
return nil, errUnrecognized
}
if offset != "" {
if mapping.Offset, err = strconv.ParseUint(offset, 16, 64); err != nil {
return nil, errUnrecognized
}
}
return mapping, nil
}
var memoryMapSentinels = []string{
"--- Memory map: ---",
"MAPPED_LIBRARIES:",
}
// isMemoryMapSentinel returns true if the string contains one of the
// known sentinels for memory map information.
func isMemoryMapSentinel(line string) bool {
for _, s := range memoryMapSentinels {
if strings.Contains(line, s) {
return true
}
}
return false
}
func (p *Profile) addLegacyFrameInfo() {
switch {
case isProfileType(p, heapzSampleTypes):
p.DropFrames, p.KeepFrames = allocRxStr, allocSkipRxStr
case isProfileType(p, contentionzSampleTypes):
p.DropFrames, p.KeepFrames = lockRxStr, ""
default:
p.DropFrames, p.KeepFrames = cpuProfilerRxStr, ""
}
}
var heapzSampleTypes = [][]string{
{"allocations", "size"}, // early Go pprof profiles
{"objects", "space"},
{"inuse_objects", "inuse_space"},
{"alloc_objects", "alloc_space"},
{"alloc_objects", "alloc_space", "inuse_objects", "inuse_space"}, // Go pprof legacy profiles
}
var contentionzSampleTypes = [][]string{
{"contentions", "delay"},
}
func isProfileType(p *Profile, types [][]string) bool {
st := p.SampleType
nextType:
for _, t := range types {
if len(st) != len(t) {
continue
}
for i := range st {
if st[i].Type != t[i] {
continue nextType
}
}
return true
}
return false
}
var allocRxStr = strings.Join([]string{
// POSIX entry points.
`calloc`,
`cfree`,
`malloc`,
`free`,
`memalign`,
`do_memalign`,
`(__)?posix_memalign`,
`pvalloc`,
`valloc`,
`realloc`,
// TC malloc.
`tcmalloc::.*`,
`tc_calloc`,
`tc_cfree`,
`tc_malloc`,
`tc_free`,
`tc_memalign`,
`tc_posix_memalign`,
`tc_pvalloc`,
`tc_valloc`,
`tc_realloc`,
`tc_new`,
`tc_delete`,
`tc_newarray`,
`tc_deletearray`,
`tc_new_nothrow`,
`tc_newarray_nothrow`,
// Memory-allocation routines on OS X.
`malloc_zone_malloc`,
`malloc_zone_calloc`,
`malloc_zone_valloc`,
`malloc_zone_realloc`,
`malloc_zone_memalign`,
`malloc_zone_free`,
// Go runtime
`runtime\..*`,
// Other misc. memory allocation routines
`BaseArena::.*`,
`(::)?do_malloc_no_errno`,
`(::)?do_malloc_pages`,
`(::)?do_malloc`,
`DoSampledAllocation`,
`MallocedMemBlock::MallocedMemBlock`,
`_M_allocate`,
`__builtin_(vec_)?delete`,
`__builtin_(vec_)?new`,
`__gnu_cxx::new_allocator::allocate`,
`__libc_malloc`,
`__malloc_alloc_template::allocate`,
`allocate`,
`cpp_alloc`,
`operator new(\[\])?`,
`simple_alloc::allocate`,
}, `|`)
var allocSkipRxStr = strings.Join([]string{
// Preserve Go runtime frames that appear in the middle/bottom of
// the stack.
`runtime\.panic`,
`runtime\.reflectcall`,
`runtime\.call[0-9]*`,
}, `|`)
var cpuProfilerRxStr = strings.Join([]string{
`ProfileData::Add`,
`ProfileData::prof_handler`,
`CpuProfiler::prof_handler`,
`__pthread_sighandler`,
`__restore`,
}, `|`)
var lockRxStr = strings.Join([]string{
`RecordLockProfileData`,
`(base::)?RecordLockProfileData.*`,
`(base::)?SubmitMutexProfileData.*`,
`(base::)?SubmitSpinLockProfileData.*`,
`(base::Mutex::)?AwaitCommon.*`,
`(base::Mutex::)?Unlock.*`,
`(base::Mutex::)?UnlockSlow.*`,
`(base::Mutex::)?ReaderUnlock.*`,
`(base::MutexLock::)?~MutexLock.*`,
`(Mutex::)?AwaitCommon.*`,
`(Mutex::)?Unlock.*`,
`(Mutex::)?UnlockSlow.*`,
`(Mutex::)?ReaderUnlock.*`,
`(MutexLock::)?~MutexLock.*`,
`(SpinLock::)?Unlock.*`,
`(SpinLock::)?SlowUnlock.*`,
`(SpinLockHolder::)?~SpinLockHolder.*`,
}, `|`)
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