Golang Profile.Function方法代码示例

func printTopProto(w io.Writer, rpt *Report) error {
	p := rpt.prof
	o := rpt.options
	g, _, _, _ := rpt.newTrimmedGraph()
	rpt.selectOutputUnit(g)

	out := profile.Profile{
		SampleType: []*profile.ValueType{
			{Type: "cum", Unit: o.OutputUnit},
			{Type: "flat", Unit: o.OutputUnit},
		},
		TimeNanos:     p.TimeNanos,
		DurationNanos: p.DurationNanos,
		PeriodType:    p.PeriodType,
		Period:        p.Period,
	}
	var flatSum int64
	for i, n := range g.Nodes {
		name, flat, cum := n.Info.PrintableName(), n.Flat, n.Cum

		flatSum += flat
		f := &profile.Function{
			ID:         uint64(i + 1),
			Name:       name,
			SystemName: name,
		}
		l := &profile.Location{
			ID: uint64(i + 1),
			Line: []profile.Line{
				{
					Function: f,
				},
			},
		}

		fv, _ := measurement.Scale(flat, o.SampleUnit, o.OutputUnit)
		cv, _ := measurement.Scale(cum, o.SampleUnit, o.OutputUnit)
		s := &profile.Sample{
			Location: []*profile.Location{l},
			Value:    []int64{int64(cv), int64(fv)},
		}
		out.Function = append(out.Function, f)
		out.Location = append(out.Location, l)
		out.Sample = append(out.Sample, s)
	}

	return out.Write(w)
}

// symbolizeMapping symbolizes locations belonging to a Mapping by querying
// a symbolz handler. An offset is applied to all addresses to take care of
// normalization occured for merged Mappings.
func symbolizeMapping(source string, offset int64, syms func(string, string) ([]byte, error), m *profile.Mapping, p *profile.Profile) error {
	// Construct query of addresses to symbolize.
	var a []string
	for _, l := range p.Location {
		if l.Mapping == m && l.Address != 0 && len(l.Line) == 0 {
			// Compensate for normalization.
			addr := int64(l.Address) + offset
			if addr < 0 {
				return fmt.Errorf("unexpected negative adjusted address, mapping %v source %d, offset %d", l.Mapping, l.Address, offset)
			}
			a = append(a, fmt.Sprintf("%#x", addr))
		}
	}

	if len(a) == 0 {
		// No addresses to symbolize.
		return nil
	}

	lines := make(map[uint64]profile.Line)
	functions := make(map[string]*profile.Function)

	b, err := syms(source, strings.Join(a, "+"))
	if err != nil {
		return err
	}

	buf := bytes.NewBuffer(b)
	for {
		l, err := buf.ReadString('\n')

		if err != nil {
			if err == io.EOF {
				break
			}
			return err
		}

		if symbol := symbolzRE.FindStringSubmatch(l); len(symbol) == 3 {
			addr, err := strconv.ParseInt(symbol[1], 0, 64)
			if err != nil {
				return fmt.Errorf("unexpected parse failure %s: %v", symbol[1], err)
			}
			if addr < 0 {
				return fmt.Errorf("unexpected negative adjusted address, source %s, offset %d", symbol[1], offset)
			}
			// Reapply offset expected by the profile.
			addr -= offset

			name := symbol[2]
			fn := functions[name]
			if fn == nil {
				fn = &profile.Function{
					ID:         uint64(len(p.Function) + 1),
					Name:       name,
					SystemName: name,
				}
				functions[name] = fn
				p.Function = append(p.Function, fn)
			}

			lines[uint64(addr)] = profile.Line{Function: fn}
		}
	}

	for _, l := range p.Location {
		if l.Mapping != m {
			continue
		}
		if line, ok := lines[l.Address]; ok {
			l.Line = []profile.Line{line}
		}
	}

	return nil
}