Function parseContention

profile/legacy_profile.go:683–800

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.

(b []byte)

// "--- 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