"regexp": {"L2", "regexp/syntax"},
"regexp/syntax": {"L2"},
"runtime/debug": {"L2", "fmt", "io/ioutil", "os", "time"},
- "runtime/pprof": {"L2", "compress/gzip", "context", "fmt", "io/ioutil", "os", "text/tabwriter", "time"},
+ "runtime/pprof": {"L2", "compress/gzip", "context", "encoding/binary", "fmt", "io/ioutil", "os", "text/tabwriter", "time"},
"runtime/trace": {"L0"},
"text/tabwriter": {"L2"},
--- /dev/null
+// Copyright 2017 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 pprof
+
+import (
+ "encoding/binary"
+ "errors"
+ "fmt"
+ "os"
+)
+
+var (
+ errBadELF = errors.New("malformed ELF binary")
+ errNoBuildID = errors.New("no NT_GNU_BUILD_ID found in ELF binary")
+)
+
+// elfBuildID returns the GNU build ID of the named ELF binary,
+// without introducing a dependency on debug/elf and its dependencies.
+func elfBuildID(file string) (string, error) {
+ buf := make([]byte, 256)
+ f, err := os.Open(file)
+ if err != nil {
+ return "", err
+ }
+ defer f.Close()
+
+ if _, err := f.ReadAt(buf[:64], 0); err != nil {
+ return "", err
+ }
+
+ // ELF file begins with \x7F E L F.
+ if buf[0] != 0x7F || buf[1] != 'E' || buf[2] != 'L' || buf[3] != 'F' {
+ return "", errBadELF
+ }
+
+ var byteOrder binary.ByteOrder
+ switch buf[5] {
+ default:
+ return "", errBadELF
+ case 1: // little-endian
+ byteOrder = binary.LittleEndian
+ case 2: // big-endian
+ byteOrder = binary.BigEndian
+ }
+
+ var shnum int
+ var shoff, shentsize int64
+ switch buf[4] {
+ default:
+ return "", errBadELF
+ case 1: // 32-bit file header
+ shoff = int64(byteOrder.Uint32(buf[32:]))
+ shentsize = int64(byteOrder.Uint16(buf[46:]))
+ if shentsize != 40 {
+ return "", errBadELF
+ }
+ shnum = int(byteOrder.Uint16(buf[48:]))
+ case 2: // 64-bit file header
+ shoff = int64(byteOrder.Uint64(buf[40:]))
+ shentsize = int64(byteOrder.Uint16(buf[58:]))
+ if shentsize != 64 {
+ return "", errBadELF
+ }
+ shnum = int(byteOrder.Uint16(buf[60:]))
+ }
+
+ for i := 0; i < shnum; i++ {
+ if _, err := f.ReadAt(buf[:shentsize], shoff+int64(i)*shentsize); err != nil {
+ return "", err
+ }
+ if typ := byteOrder.Uint32(buf[4:]); typ != 7 { // SHT_NOTE
+ continue
+ }
+ var off, size int64
+ if shentsize == 40 {
+ // 32-bit section header
+ off = int64(byteOrder.Uint32(buf[16:]))
+ size = int64(byteOrder.Uint32(buf[20:]))
+ } else {
+ // 64-bit section header
+ off = int64(byteOrder.Uint64(buf[24:]))
+ size = int64(byteOrder.Uint64(buf[32:]))
+ }
+ size += off
+ for off < size {
+ if _, err := f.ReadAt(buf[:16], off); err != nil { // room for header + name GNU\x00
+ return "", err
+ }
+ nameSize := int(byteOrder.Uint32(buf[0:]))
+ descSize := int(byteOrder.Uint32(buf[4:]))
+ noteType := int(byteOrder.Uint32(buf[8:]))
+ descOff := off + int64(12+(nameSize+3)&^3)
+ off = descOff + int64((descSize+3)&^3)
+ if nameSize != 4 || noteType != 3 || buf[12] != 'G' || buf[13] != 'N' || buf[14] != 'U' || buf[15] != '\x00' { // want name GNU\x00 type 3 (NT_GNU_BUILD_ID)
+ continue
+ }
+ if descSize > len(buf) {
+ return "", errBadELF
+ }
+ if _, err := f.ReadAt(buf[:descSize], descOff); err != nil {
+ return "", err
+ }
+ return fmt.Sprintf("%x", buf[:descSize]), nil
+ }
+ }
+ return "", errNoBuildID
+}
}
// pbMapping encodes a Mapping message to b.pb.
-func (b *profileBuilder) pbMapping(tag int, id, base, limit, offset uint64, file string) {
+func (b *profileBuilder) pbMapping(tag int, id, base, limit, offset uint64, file, buildID string) {
start := b.pb.startMessage()
b.pb.uint64Opt(tagMapping_ID, id)
b.pb.uint64Opt(tagMapping_Start, base)
b.pb.uint64Opt(tagMapping_Limit, limit)
b.pb.uint64Opt(tagMapping_Offset, offset)
b.pb.int64Opt(tagMapping_Filename, b.stringIndex(file))
+ b.pb.int64Opt(tagMapping_BuildID, b.stringIndex(buildID))
// TODO: Set any of HasInlineFrames, HasFunctions, HasFilenames, HasLineNumbers?
// It seems like they should all be true, but they've never been set.
b.pb.endMessage(tag, start)
}
next() // dev
next() // inode
- file := line
- if file == nil {
+ if line == nil {
continue
}
+ file := string(line)
// TODO: pprof's remapMappingIDs makes two adjustments:
// 1. If there is an /anon_hugepage mapping first and it is
// If we do need them, they would go here, before we
// enter the mappings into b.mem in the first place.
+ buildID, _ := elfBuildID(file)
b.mem = append(b.mem, memMap{uintptr(lo), uintptr(hi)})
- b.pbMapping(tagProfile_Mapping, uint64(len(b.mem)), lo, hi, offset, string(file))
+ b.pbMapping(tagProfile_Mapping, uint64(len(b.mem)), lo, hi, offset, file, buildID)
}
}
}
addr1 = mprof.Mapping[0].Start
map1 = mprof.Mapping[0]
+ map1.BuildID, _ = elfBuildID(map1.File)
addr2 = mprof.Mapping[1].Start
map2 = mprof.Mapping[1]
+ map2.BuildID, _ = elfBuildID(map2.File)
} else {
addr1 = uint64(funcPC(f1))
addr2 = uint64(funcPC(f2))
--- /dev/null
+These binaries were generated by:
+
+$ cat empty.s
+.global _start
+_start:
+$ as --32 -o empty.o empty.s && ld --build-id -m elf_i386 -o test32 empty.o
+$ as --64 -o empty.o empty.s && ld --build-id -o test64 empty.o
+$ powerpc-linux-gnu-as -o empty.o empty.s && powerpc-linux-gnu-ld --build-id -o test32be empty.o
+$ powerpc64-linux-gnu-as -o empty.o empty.s && powerpc64-linux-gnu-ld --build-id -o test64be empty.o