collector/ethtool: Expose NIC channel configuration

collector/ethtool_linux.go

@@ -49,6 +49,7 @@ type Ethtool interface {
 	DriverInfo(string) (ethtool.DrvInfo, error)
 	Stats(string) (map[string]uint64, error)
 	LinkInfo(string) (ethtool.EthtoolCmd, error)
+	GetChannels(string) (ethtool.Channels, error)
 }
 
 type ethtoolLibrary struct {
@@ -69,6 +70,10 @@ func (e *ethtoolLibrary) LinkInfo(intf string) (ethtool.EthtoolCmd, error) {
 	return ethtoolCmd, err
 }
 
+func (e *ethtoolLibrary) GetChannels(intf string) (ethtool.Channels, error) {
+	return e.ethtool.GetChannels(intf)
+}
+
 type ethtoolCollector struct {
 	fs             sysfs.FS
 	entries        map[string]*prometheus.Desc
@@ -199,6 +204,21 @@ func makeEthtoolCollector(logger *slog.Logger) (*ethtoolCollector, error) {
 				"If this port is using autonegotiate",
 				[]string{"device"}, nil,
 			),
+
+			// channel info
+			//
+			// Each metric will have four instances differentiated by its type,
+			// with type being one of rx, tx, other, or combined.
+			"channels_max": prometheus.NewDesc(
+				prometheus.BuildFQName(namespace, "ethtool", "channels_max"),
+				"Maximum supported network interface channels",
+				[]string{"device", "type"}, nil,
+			),
+			"channels_current": prometheus.NewDesc(
+				prometheus.BuildFQName(namespace, "ethtool", "channels_current"),
+				"Currently configured network interface channels",
+				[]string{"device", "type"}, nil,
+			),
 		},
 		infoDesc: prometheus.NewDesc(
 			prometheus.BuildFQName(namespace, "ethtool", "info"),
@@ -370,6 +390,33 @@ func (c *ethtoolCollector) updateSpeeds(ch chan<- prometheus.Metric, prefix stri
 	}
 }
 
+func (c *ethtoolCollector) updateChannels(ch chan<- prometheus.Metric, device string) {
+	channels, err := c.ethtool.GetChannels(device)
+	if err != nil {
+		if errno, ok := err.(syscall.Errno); ok {
+			if err == unix.EOPNOTSUPP {
+				c.logger.Debug("ethtool driver info error", "err", err, "device", device, "errno", uint(errno))
+			} else if errno != 0 {
+				c.logger.Error("ethtool get channels error", "err", err, "device", device, "errno", uint(errno))
+			}
+		} else {
+			c.logger.Error("ethtool get channels error", "err", err, "device", device)
+		}
+
+		return
+	}
+
+	ch <- prometheus.MustNewConstMetric(c.entry("channels_max"), prometheus.GaugeValue, float64(channels.MaxRx), device, "rx")
+	ch <- prometheus.MustNewConstMetric(c.entry("channels_max"), prometheus.GaugeValue, float64(channels.MaxTx), device, "tx")
+	ch <- prometheus.MustNewConstMetric(c.entry("channels_max"), prometheus.GaugeValue, float64(channels.MaxOther), device, "other")
+	ch <- prometheus.MustNewConstMetric(c.entry("channels_max"), prometheus.GaugeValue, float64(channels.MaxCombined), device, "combined")
+
+	ch <- prometheus.MustNewConstMetric(c.entry("channels_current"), prometheus.GaugeValue, float64(channels.RxCount), device, "rx")
+	ch <- prometheus.MustNewConstMetric(c.entry("channels_current"), prometheus.GaugeValue, float64(channels.TxCount), device, "tx")
+	ch <- prometheus.MustNewConstMetric(c.entry("channels_current"), prometheus.GaugeValue, float64(channels.OtherCount), device, "other")
+	ch <- prometheus.MustNewConstMetric(c.entry("channels_current"), prometheus.GaugeValue, float64(channels.CombinedCount), device, "combined")
+}
+
 func (c *ethtoolCollector) Update(ch chan<- prometheus.Metric) error {
 	netClass, err := c.fs.NetClassDevices()
 	if err != nil {
@@ -429,6 +476,8 @@ func (c *ethtoolCollector) Update(ch chan<- prometheus.Metric) error {
 			}
 		}
 
+		c.updateChannels(ch, device)
+
 		stats, err = c.ethtool.Stats(device)
 
 		// If Stats() returns EOPNOTSUPP it doesn't support ethtool stats. Log that only at Debug level.

collector/ethtool_linux_test.go

@@ -257,6 +257,81 @@ func (e *EthtoolFixture) LinkInfo(intf string) (ethtool.EthtoolCmd, error) {
 	return res, err
 }
 
+func (e *EthtoolFixture) GetChannels(intf string) (ethtool.Channels, error) {
+	res := ethtool.Channels{}
+
+	fixtureFile, err := os.Open(filepath.Join(e.fixturePath, intf, "channels"))
+	if e, ok := err.(*os.PathError); ok && e.Err == syscall.ENOENT {
+		// The fixture for this interface doesn't exist. Translate that to unix.EOPNOTSUPP
+		// to replicate an interface that doesn't support ethtool driver info
+		return res, unix.EOPNOTSUPP
+	}
+	if err != nil {
+		return res, err
+	}
+	defer fixtureFile.Close()
+
+	scanner := bufio.NewScanner(fixtureFile)
+	currentConfig := false
+
+	for scanner.Scan() {
+		line := scanner.Text()
+		if strings.HasPrefix(line, "#") || strings.HasPrefix(line, "Channel parameters for") || strings.HasPrefix(line, "Pre-set maximums") {
+			continue
+		}
+
+		line = strings.Trim(line, " ")
+		items := strings.Split(line, ":")
+		fmt.Printf("line: %s\n", line)
+		fmt.Printf("items: %s\n", strings.Join(items, ","))
+		switch items[0] {
+		case "Current hardware settings":
+			currentConfig = true
+		case "RX":
+			if currentConfig {
+				res.RxCount = readChannel(items[1])
+			} else {
+				res.MaxRx = readChannel(items[1])
+			}
+		case "TX":
+			if currentConfig {
+				res.TxCount = readChannel(items[1])
+			} else {
+				res.MaxTx = readChannel(items[1])
+			}
+		case "Other":
+			if currentConfig {
+				res.OtherCount = readChannel(items[1])
+			} else {
+				res.MaxOther = readChannel(items[1])
+			}
+		case "Combined":
+			if currentConfig {
+				res.CombinedCount = readChannel(items[1])
+			} else {
+				res.MaxCombined = readChannel(items[1])
+			}
+		}
+	}
+
+	return res, nil
+}
+
+func readChannel(val string) uint32 {
+	val = strings.TrimSpace(val)
+	if val == "n/a" {
+		return 0
+	}
+
+	intVal, err := strconv.ParseUint(val, 10, 32)
+	if err != nil {
+		return 0
+	}
+
+	return uint32(intVal)
+
+}
+
 func NewEthtoolTestCollector(logger *slog.Logger) (Collector, error) {
 	collector, err := makeEthtoolCollector(logger)
 	if err != nil {
@@ -291,6 +366,18 @@ func TestEthToolCollector(t *testing.T) {
 	testcase := `# HELP node_ethtool_align_errors Network interface align_errors
 # TYPE node_ethtool_align_errors untyped
 node_ethtool_align_errors{device="eth0"} 0
+# HELP node_ethtool_channels_current Currently configured network interface channels
+# TYPE node_ethtool_channels_current gauge
+node_ethtool_channels_current{device="eth0",type="combined"} 128
+node_ethtool_channels_current{device="eth0",type="other"} 1
+node_ethtool_channels_current{device="eth0",type="rx"} 0
+node_ethtool_channels_current{device="eth0",type="tx"} 0
+# HELP node_ethtool_channels_max Maximum supported network interface channels
+# TYPE node_ethtool_channels_max gauge
+node_ethtool_channels_max{device="eth0",type="combined"} 252
+node_ethtool_channels_max{device="eth0",type="other"} 1
+node_ethtool_channels_max{device="eth0",type="rx"} 252
+node_ethtool_channels_max{device="eth0",type="tx"} 252
 # HELP node_ethtool_info A metric with a constant '1' value labeled by bus_info, device, driver, expansion_rom_version, firmware_version, version.
 # TYPE node_ethtool_info gauge
 node_ethtool_info{bus_info="0000:00:1f.6",device="eth0",driver="e1000e",expansion_rom_version="",firmware_version="0.5-4",version="5.11.0-22-generic"} 1

collector/fixtures/ethtool/eth0/channels

@@ -0,0 +1,13 @@
+# ethtool --show-channels eth0
+Channel parameters for eth0:
+Pre-set maximums:
+RX:		252
+TX:		252
+Other:		1
+Combined:	252
+Current hardware settings:
+# Testing n/a (which will be translated into 0)
+RX:		n/a
+TX:		0
+Other:		1
+Combined:	128