func()

in pkg/exporter/probe/tracetcpreset/tracetcpreset.go [77:142]
52 lines of code
12 McCabe index (conditional complexity)

func (p *tcpResetProbe) perfLoop() {
	for {
		record, err := p.perfReader.Read()
		if err != nil {
			if errors.Is(err, ringbuf.ErrClosed) {
				log.Infof("%s received signal, exiting..", probeName)
				return
			}
			log.Errorf("%s failed reading from reader, err: %v", probeName, err)
			continue
		}

		if record.LostSamples != 0 {
			log.Infof("%s perf event ring buffer full, drop: %d", probeName, record.LostSamples)
			continue
		}

		var event bpfInspTcpresetEventT
		if err := binary.Read(bytes.NewBuffer(record.RawSample), binary.LittleEndian, &event); err != nil {
			log.Infof("%s failed parsing event, err: %v", probeName, err)
			continue
		}

		/*
			#define RESET_NOSOCK 1
			#define RESET_ACTIVE 2
			#define RESET_PROCESS 4
			#define RESET_RECEIVE 8
		*/

		var eventType probe.EventType

		switch event.Type {
		case 1:
			eventType = TCPRESET_NOSOCK
		case 2:
			eventType = TCPRESET_ACTIVE
		case 4:
			eventType = TCPRESET_PROCESS
		case 8:
			eventType = TCPRESET_RECEIVE
		default:
			log.Infof("%s got invalid perf event type %d, data: %s", probeName, event.Type, util.ToJSONString(event))
			continue
		}

		if event.Tuple.L3Proto == syscall.ETH_P_IPV6 {
			log.Infof("%s ignore event of ipv6 proto", probeName)
			continue
		}

		evt := &probe.Event{
			Timestamp: time.Now().UnixNano(),
			Type:      eventType,
			Labels:    probe.LegacyEventLabels(event.SkbMeta.Netns),
		}

		tuple := fmt.Sprintf("protocol=%s saddr=%s sport=%d daddr=%s dport=%d ", bpfutil.GetProtoStr(event.Tuple.L4Proto), bpfutil.GetAddrStr(event.Tuple.L3Proto, *(*[16]byte)(unsafe.Pointer(&event.Tuple.Saddr))), bits.ReverseBytes16(event.Tuple.Sport), bpfutil.GetAddrStr(event.Tuple.L3Proto, *(*[16]byte)(unsafe.Pointer(&event.Tuple.Daddr))), bits.ReverseBytes16(event.Tuple.Dport))
		stateStr := bpfutil.GetSkcStateStr(event.State)
		evt.Message = fmt.Sprintf("%s state:%s ", tuple, stateStr)
		if p.sink != nil {
			log.Debugf("%s sink event: %s", probeName, util.ToJSONString(evt))
			p.sink <- evt
		}
	}
}