diff options
Diffstat (limited to 'src/cmd/vendor/github.com/google/pprof/internal/binutils/binutils.go')
| -rw-r--r-- | src/cmd/vendor/github.com/google/pprof/internal/binutils/binutils.go | 80 |
1 files changed, 59 insertions, 21 deletions
diff --git a/src/cmd/vendor/github.com/google/pprof/internal/binutils/binutils.go b/src/cmd/vendor/github.com/google/pprof/internal/binutils/binutils.go index 9854c9a262..9a82cb8e92 100644 --- a/src/cmd/vendor/github.com/google/pprof/internal/binutils/binutils.go +++ b/src/cmd/vendor/github.com/google/pprof/internal/binutils/binutils.go @@ -24,14 +24,21 @@ import ( "path/filepath" "regexp" "strings" + "sync" "github.com/google/pprof/internal/elfexec" "github.com/google/pprof/internal/plugin" ) // A Binutils implements plugin.ObjTool by invoking the GNU binutils. -// SetConfig must be called before any of the other methods. type Binutils struct { + mu sync.Mutex + rep *binrep +} + +// binrep is an immutable representation for Binutils. It is atomically +// replaced on every mutation to provide thread-safe access. +type binrep struct { // Commands to invoke. llvmSymbolizer string llvmSymbolizerFound bool @@ -47,11 +54,38 @@ type Binutils struct { fast bool } +// get returns the current representation for bu, initializing it if necessary. +func (bu *Binutils) get() *binrep { + bu.mu.Lock() + r := bu.rep + if r == nil { + r = &binrep{} + initTools(r, "") + bu.rep = r + } + bu.mu.Unlock() + return r +} + +// update modifies the rep for bu via the supplied function. +func (bu *Binutils) update(fn func(r *binrep)) { + r := &binrep{} + bu.mu.Lock() + defer bu.mu.Unlock() + if bu.rep == nil { + initTools(r, "") + } else { + *r = *bu.rep + } + fn(r) + bu.rep = r +} + // SetFastSymbolization sets a toggle that makes binutils use fast // symbolization (using nm), which is much faster than addr2line but // provides only symbol name information (no file/line). -func (b *Binutils) SetFastSymbolization(fast bool) { - b.fast = fast +func (bu *Binutils) SetFastSymbolization(fast bool) { + bu.update(func(r *binrep) { r.fast = fast }) } // SetTools processes the contents of the tools option. It @@ -59,7 +93,11 @@ func (b *Binutils) SetFastSymbolization(fast bool) { // of the form t:path, where cmd will be used to look only for the // tool named t. If t is not specified, the path is searched for all // tools. -func (b *Binutils) SetTools(config string) { +func (bu *Binutils) SetTools(config string) { + bu.update(func(r *binrep) { initTools(r, config) }) +} + +func initTools(b *binrep, config string) { // paths collect paths per tool; Key "" contains the default. paths := make(map[string][]string) for _, t := range strings.Split(config, ",") { @@ -91,11 +129,8 @@ func findExe(cmd string, paths []string) (string, bool) { // Disasm returns the assembly instructions for the specified address range // of a binary. -func (b *Binutils) Disasm(file string, start, end uint64) ([]plugin.Inst, error) { - if b.addr2line == "" { - // Update the command invocations if not initialized. - b.SetTools("") - } +func (bu *Binutils) Disasm(file string, start, end uint64) ([]plugin.Inst, error) { + b := bu.get() cmd := exec.Command(b.objdump, "-d", "-C", "--no-show-raw-insn", "-l", fmt.Sprintf("--start-address=%#x", start), fmt.Sprintf("--stop-address=%#x", end), @@ -109,11 +144,8 @@ func (b *Binutils) Disasm(file string, start, end uint64) ([]plugin.Inst, error) } // Open satisfies the plugin.ObjTool interface. -func (b *Binutils) Open(name string, start, limit, offset uint64) (plugin.ObjFile, error) { - if b.addr2line == "" { - // Update the command invocations if not initialized. - b.SetTools("") - } +func (bu *Binutils) Open(name string, start, limit, offset uint64) (plugin.ObjFile, error) { + b := bu.get() // Make sure file is a supported executable. // The pprof driver uses Open to sniff the difference @@ -140,7 +172,7 @@ func (b *Binutils) Open(name string, start, limit, offset uint64) (plugin.ObjFil return nil, fmt.Errorf("unrecognized binary: %s", name) } -func (b *Binutils) openMachO(name string, start, limit, offset uint64) (plugin.ObjFile, error) { +func (b *binrep) openMachO(name string, start, limit, offset uint64) (plugin.ObjFile, error) { of, err := macho.Open(name) if err != nil { return nil, fmt.Errorf("Parsing %s: %v", name, err) @@ -153,7 +185,7 @@ func (b *Binutils) openMachO(name string, start, limit, offset uint64) (plugin.O return &fileAddr2Line{file: file{b: b, name: name}}, nil } -func (b *Binutils) openELF(name string, start, limit, offset uint64) (plugin.ObjFile, error) { +func (b *binrep) openELF(name string, start, limit, offset uint64) (plugin.ObjFile, error) { ef, err := elf.Open(name) if err != nil { return nil, fmt.Errorf("Parsing %s: %v", name, err) @@ -202,7 +234,7 @@ func (b *Binutils) openELF(name string, start, limit, offset uint64) (plugin.Obj // file implements the binutils.ObjFile interface. type file struct { - b *Binutils + b *binrep name string base uint64 buildID string @@ -263,22 +295,27 @@ func (f *fileNM) SourceLine(addr uint64) ([]plugin.Frame, error) { // information). It can be slow for large binaries with debug // information. type fileAddr2Line struct { + once sync.Once file addr2liner *addr2Liner llvmSymbolizer *llvmSymbolizer } func (f *fileAddr2Line) SourceLine(addr uint64) ([]plugin.Frame, error) { + f.once.Do(f.init) if f.llvmSymbolizer != nil { return f.llvmSymbolizer.addrInfo(addr) } if f.addr2liner != nil { return f.addr2liner.addrInfo(addr) } + return nil, fmt.Errorf("could not find local addr2liner") +} +func (f *fileAddr2Line) init() { if llvmSymbolizer, err := newLLVMSymbolizer(f.b.llvmSymbolizer, f.name, f.base); err == nil { f.llvmSymbolizer = llvmSymbolizer - return f.llvmSymbolizer.addrInfo(addr) + return } if addr2liner, err := newAddr2Liner(f.b.addr2line, f.name, f.base); err == nil { @@ -290,13 +327,14 @@ func (f *fileAddr2Line) SourceLine(addr uint64) ([]plugin.Frame, error) { if nm, err := newAddr2LinerNM(f.b.nm, f.name, f.base); err == nil { f.addr2liner.nm = nm } - return f.addr2liner.addrInfo(addr) } - - return nil, fmt.Errorf("could not find local addr2liner") } func (f *fileAddr2Line) Close() error { + if f.llvmSymbolizer != nil { + f.llvmSymbolizer.rw.close() + f.llvmSymbolizer = nil + } if f.addr2liner != nil { f.addr2liner.rw.close() f.addr2liner = nil |