blob: 4baddbc029a8d2dc587650a1b99243bc20b9b619 [file] [log] [blame]
// Copyright 2015 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 gc
import (
"os"
"runtime"
"runtime/pprof"
"cmd/compile/internal/base"
)
var (
memprofilerate int64
traceHandler func(string)
)
func startProfile() {
if base.Flag.CPUProfile != "" {
f, err := os.Create(base.Flag.CPUProfile)
if err != nil {
base.Fatalf("%v", err)
}
if err := pprof.StartCPUProfile(f); err != nil {
base.Fatalf("%v", err)
}
base.AtExit(pprof.StopCPUProfile)
}
if base.Flag.MemProfile != "" {
if memprofilerate != 0 {
runtime.MemProfileRate = int(memprofilerate)
}
f, err := os.Create(base.Flag.MemProfile)
if err != nil {
base.Fatalf("%v", err)
}
base.AtExit(func() {
// Profile all outstanding allocations.
runtime.GC()
// compilebench parses the memory profile to extract memstats,
// which are only written in the legacy pprof format.
// See golang.org/issue/18641 and runtime/pprof/pprof.go:writeHeap.
const writeLegacyFormat = 1
if err := pprof.Lookup("heap").WriteTo(f, writeLegacyFormat); err != nil {
base.Fatalf("%v", err)
}
})
} else {
// Not doing memory profiling; disable it entirely.
runtime.MemProfileRate = 0
}
if base.Flag.BlockProfile != "" {
f, err := os.Create(base.Flag.BlockProfile)
if err != nil {
base.Fatalf("%v", err)
}
runtime.SetBlockProfileRate(1)
base.AtExit(func() {
pprof.Lookup("block").WriteTo(f, 0)
f.Close()
})
}
if base.Flag.MutexProfile != "" {
f, err := os.Create(base.Flag.MutexProfile)
if err != nil {
base.Fatalf("%v", err)
}
startMutexProfiling()
base.AtExit(func() {
pprof.Lookup("mutex").WriteTo(f, 0)
f.Close()
})
}
if base.Flag.TraceProfile != "" && traceHandler != nil {
traceHandler(base.Flag.TraceProfile)
}
}