Golang cgroups.GetCgroupMounts函數代碼示例

// Get information about the cgroup subsystems.
func GetCgroupSubsystems() (CgroupSubsystems, error) {
	// Get all cgroup mounts.
	allCgroups, err := cgroups.GetCgroupMounts()
	if err != nil {
		return CgroupSubsystems{}, err
	}
	if len(allCgroups) == 0 {
		return CgroupSubsystems{}, fmt.Errorf("failed to find cgroup mounts")
	}

	// Trim the mounts to only the subsystems we care about.
	supportedCgroups := make([]cgroups.Mount, 0, len(allCgroups))
	mountPoints := make(map[string]string, len(allCgroups))
	for _, mount := range allCgroups {
		for _, subsystem := range mount.Subsystems {
			if _, ok := supportedSubsystems[subsystem]; ok {
				supportedCgroups = append(supportedCgroups, mount)
				mountPoints[subsystem] = mount.Mountpoint
			}
		}
	}

	return CgroupSubsystems{
		Mounts:      supportedCgroups,
		MountPoints: mountPoints,
	}, nil
}

func getCgroupMounts(m *configs.Mount) ([]*configs.Mount, error) {
	mounts, err := cgroups.GetCgroupMounts()
	if err != nil {
		return nil, err
	}

	var binds []*configs.Mount

	for _, mm := range mounts {
		dir, err := mm.GetThisCgroupDir()
		if err != nil {
			return nil, err
		}
		relDir, err := filepath.Rel(mm.Root, dir)
		if err != nil {
			return nil, err
		}
		binds = append(binds, &configs.Mount{
			Device:      "bind",
			Source:      filepath.Join(mm.Mountpoint, relDir),
			Destination: filepath.Join(m.Destination, strings.Join(mm.Subsystems, ",")),
			Flags:       syscall.MS_BIND | syscall.MS_REC | m.Flags,
		})
	}

	return binds, nil
}

func findCgroupMountpoints() (map[string]string, error) {
	cgMounts, err := cgroups.GetCgroupMounts()
	if err != nil {
		return nil, fmt.Errorf("Failed to parse cgroup information: %v", err)
	}
	mps := make(map[string]string)
	for _, m := range cgMounts {
		for _, ss := range m.Subsystems {
			mps[ss] = m.Mountpoint
		}
	}
	return mps, nil
}

// GetCgroupSubsystems returns information about the mounted cgroup subsystems
func GetCgroupSubsystems() (*CgroupSubsystems, error) {
	// get all cgroup mounts.
	allCgroups, err := libcontainercgroups.GetCgroupMounts(true)
	if err != nil {
		return &CgroupSubsystems{}, err
	}
	if len(allCgroups) == 0 {
		return &CgroupSubsystems{}, fmt.Errorf("failed to find cgroup mounts")
	}
	mountPoints := make(map[string]string, len(allCgroups))
	for _, mount := range allCgroups {
		for _, subsystem := range mount.Subsystems {
			mountPoints[subsystem] = mount.Mountpoint
		}
	}
	return &CgroupSubsystems{
		Mounts:      allCgroups,
		MountPoints: mountPoints,
	}, nil
}

// GetCgroupSubsystems returns information about the mounted cgroup subsystems
func getCgroupSubsystems() (*cgroupSubsystems, error) {
	// Get all cgroup mounts.
	allCgroups, err := libcontainercgroups.GetCgroupMounts()
	if err != nil {
		return &cgroupSubsystems{}, err
	}
	if len(allCgroups) == 0 {
		return &cgroupSubsystems{}, fmt.Errorf("failed to find cgroup mounts")
	}

	//TODO(@dubstack) should we trim to only the supported ones
	mountPoints := make(map[string]string, len(allCgroups))
	for _, mount := range allCgroups {
		for _, subsystem := range mount.Subsystems {
			mountPoints[subsystem] = mount.Mountpoint
		}
	}
	return &cgroupSubsystems{
		mounts:      allCgroups,
		mountPoints: mountPoints,
	}, nil
}

func mountToRootfs(m *configs.Mount, rootfs, mountLabel string) error {
	var (
		dest = m.Destination
		data = label.FormatMountLabel(m.Data, mountLabel)
	)
	if !strings.HasPrefix(dest, rootfs) {
		dest = filepath.Join(rootfs, dest)
	}

	switch m.Device {
	case "proc", "sysfs":
		if err := os.MkdirAll(dest, 0755); err != nil && !os.IsExist(err) {
			return err
		}
		return syscall.Mount(m.Source, dest, m.Device, uintptr(m.Flags), "")
	case "mqueue":
		if err := os.MkdirAll(dest, 0755); err != nil && !os.IsExist(err) {
			return err
		}
		if err := syscall.Mount(m.Source, dest, m.Device, uintptr(m.Flags), ""); err != nil {
			return err
		}
		return label.SetFileLabel(dest, mountLabel)
	case "tmpfs":
		stat, err := os.Stat(dest)
		if err != nil {
			if err := os.MkdirAll(dest, 0755); err != nil && !os.IsExist(err) {
				return err
			}
		}
		if err := syscall.Mount(m.Source, dest, m.Device, uintptr(m.Flags), data); err != nil {
			return err
		}
		if stat != nil {
			if err = os.Chmod(dest, stat.Mode()); err != nil {
				return err
			}
		}
		return nil
	case "devpts":
		if err := os.MkdirAll(dest, 0755); err != nil && !os.IsExist(err) {
			return err
		}
		return syscall.Mount(m.Source, dest, m.Device, uintptr(m.Flags), data)
	case "bind":
		stat, err := os.Stat(m.Source)
		if err != nil {
			// error out if the source of a bind mount does not exist as we will be
			// unable to bind anything to it.
			return err
		}
		// ensure that the destination of the bind mount is resolved of symlinks at mount time because
		// any previous mounts can invalidate the next mount's destination.
		// this can happen when a user specifies mounts within other mounts to cause breakouts or other
		// evil stuff to try to escape the container's rootfs.
		if dest, err = symlink.FollowSymlinkInScope(filepath.Join(rootfs, m.Destination), rootfs); err != nil {
			return err
		}
		if err := checkMountDestination(rootfs, dest); err != nil {
			return err
		}
		if err := createIfNotExists(dest, stat.IsDir()); err != nil {
			return err
		}
		if err := syscall.Mount(m.Source, dest, m.Device, uintptr(m.Flags), data); err != nil {
			return err
		}
		if m.Flags&syscall.MS_RDONLY != 0 {
			if err := syscall.Mount(m.Source, dest, m.Device, uintptr(m.Flags|syscall.MS_REMOUNT), ""); err != nil {
				return err
			}
		}
		if m.Relabel != "" {
			if err := label.Relabel(m.Source, mountLabel, m.Relabel); err != nil {
				return err
			}
		}
		if m.Flags&syscall.MS_PRIVATE != 0 {
			if err := syscall.Mount("", dest, "none", uintptr(syscall.MS_PRIVATE), ""); err != nil {
				return err
			}
		}
	case "cgroup":
		mounts, err := cgroups.GetCgroupMounts()
		if err != nil {
			return err
		}
		var binds []*configs.Mount
		for _, mm := range mounts {
			dir, err := mm.GetThisCgroupDir()
			if err != nil {
				return err
			}
			binds = append(binds, &configs.Mount{
				Device:      "bind",
				Source:      filepath.Join(mm.Mountpoint, dir),
				Destination: filepath.Join(m.Destination, strings.Join(mm.Subsystems, ",")),
				Flags:       syscall.MS_BIND | syscall.MS_REC | syscall.MS_RDONLY,
			})
		}
//.........這裏部分代碼省略.........

func (e *Exporter) collect(ch chan<- prometheus.Metric) error {
	containers, err := e.manager.Containers()
	if err != nil {
		e.errors.WithLabelValues("list").Inc()
		return err
	}
	mounts, err := cgroups.GetCgroupMounts()
	if err != nil {
		return err
	}
	for _, container := range containers {
		cgroupPaths := make(map[string]string, len(mounts))
		for _, mount := range mounts {
			p, err := e.findCgroupPath(mount.Mountpoint, container.ID)
			if err != nil {
				continue // Ignore
			}
			for _, subsystem := range mount.Subsystems {
				cgroupPaths[subsystem] = p
			}
		}
		manager := &fs.Manager{
			Paths:   cgroupPaths,
			Cgroups: nil,
		}
		stats, err := manager.GetStats()
		if err != nil {
			e.errors.WithLabelValues("stats").Inc()
			return err
		}
		name := container.Name
		id := container.ID
		image := container.Image

		//Additional information
		cont, err := e.client.InspectContainer(container.ID)
		if err != nil {
			e.errors.WithLabelValues("dockerclient").Inc()
			return err
		}

		var labelValues = make([]string, len(e.labels))
		for index, labelName := range e.labels {
			if val, ok := cont.Config.Labels[labelName]; ok {
				labelValues[index] = val
			} else {
				labelValues[index] = ""
			}
		}

		// Last seen
		e.lastSeen.WithLabelValues(append([]string{name, id, image}, labelValues...)...).Set(float64(time.Now().Unix()))

		// CPU stats
		// - Usage
		for i, value := range stats.CpuStats.CpuUsage.PercpuUsage {
			e.cpuUsageSecondsPerCPU.WithLabelValues(append([]string{name, id, image, fmt.Sprintf("cpu%02d", i)}, labelValues...)...).Set(float64(value) / float64(time.Second))
		}

		e.cpuUsageSeconds.WithLabelValues(append([]string{name, id, image, "kernel"}, labelValues...)...).Set(float64(stats.CpuStats.CpuUsage.UsageInKernelmode) / float64(time.Second))
		e.cpuUsageSeconds.WithLabelValues(append([]string{name, id, image, "user"}, labelValues...)...).Set(float64(stats.CpuStats.CpuUsage.UsageInUsermode) / float64(time.Second))

		// - Throttling
		e.cpuThrottledPeriods.WithLabelValues(append([]string{name, id, image, "total"}, labelValues...)...).Set(float64(stats.CpuStats.ThrottlingData.Periods))
		e.cpuThrottledPeriods.WithLabelValues(append([]string{name, id, image, "throttled"}, labelValues...)...).Set(float64(stats.CpuStats.ThrottlingData.ThrottledPeriods))
		e.cpuThrottledTime.WithLabelValues(append([]string{name, id, image}, labelValues...)...).Set(float64(stats.CpuStats.ThrottlingData.ThrottledTime) / float64(time.Second))

		// Memory stats
		e.memoryUsageBytes.WithLabelValues(append([]string{name, id, image}, labelValues...)...).Set(float64(stats.MemoryStats.Usage.Usage))
		e.memoryMaxUsageBytes.WithLabelValues(append([]string{name, id, image}, labelValues...)...).Set(float64(stats.MemoryStats.Usage.MaxUsage))

		for t, value := range stats.MemoryStats.Stats {
			if isMemoryPagingCounter(t) {
				e.memoryPaging.WithLabelValues(append([]string{name, id, image, t}, labelValues...)...).Set(float64(value))
			} else {
				e.memoryStats.WithLabelValues(append([]string{name, id, image, t}, labelValues...)...).Set(float64(value))
			}
		}
		e.memoryFailures.WithLabelValues(append([]string{name, id, image}, labelValues...)...).Set(float64(stats.MemoryStats.Usage.Failcnt))

		// BlkioStats
		devMap, err := newDeviceMap(procDiskStats)
		if err != nil {
			return err
		}
		for _, stat := range stats.BlkioStats.IoServiceBytesRecursive {
			e.blkioIoServiceBytesRecursive.WithLabelValues(append([]string{name, id, image, devMap.name(stat.Major, stat.Minor), stat.Op}, labelValues...)...).Set(float64(stat.Value))
		}
		for _, stat := range stats.BlkioStats.IoServicedRecursive {
			e.blkioIoServicedRecursive.WithLabelValues(append([]string{name, id, image, devMap.name(stat.Major, stat.Minor), stat.Op}, labelValues...)...).Set(float64(stat.Value))
		}
		for _, stat := range stats.BlkioStats.IoQueuedRecursive {
			e.blkioIoQueuedRecursive.WithLabelValues(append([]string{name, id, image, devMap.name(stat.Major, stat.Minor), stat.Op}, labelValues...)...).Set(float64(stat.Value))
		}
		for _, stat := range stats.BlkioStats.SectorsRecursive {
			e.blkioSectorsRecursive.WithLabelValues(append([]string{name, id, image, devMap.name(stat.Major, stat.Minor)}, labelValues...)...).Set(float64(stat.Value))
		}
	}
	return nil
}