Golang cgroups.FindCgroupMountpoint函數代碼示例

func checkCgroupMem(quiet bool) *cgroupMemInfo {
	info := &cgroupMemInfo{}
	mountPoint, err := cgroups.FindCgroupMountpoint("memory")
	if err != nil {
		if !quiet {
			logrus.Warnf("Your kernel does not support cgroup memory limit: %v", err)
		}
		return info
	}
	info.MemoryLimit = true

	info.SwapLimit = cgroupEnabled(mountPoint, "memory.memsw.limit_in_bytes")
	if !quiet && !info.SwapLimit {
		logrus.Warn("Your kernel does not support swap memory limit.")
	}
	info.OomKillDisable = cgroupEnabled(mountPoint, "memory.oom_control")
	if !quiet && !info.OomKillDisable {
		logrus.Warnf("Your kernel does not support oom control.")
	}
	info.MemorySwappiness = cgroupEnabled(mountPoint, "memory.swappiness")
	if !quiet && !info.MemorySwappiness {
		logrus.Warnf("Your kernel does not support memory swappiness.")
	}

	return info
}

func checkCgroupCPU(quiet bool) *cgroupCPUInfo {
	info := &cgroupCPUInfo{}
	mountPoint, err := cgroups.FindCgroupMountpoint("cpu")
	if err != nil {
		if !quiet {
			logrus.Warn(err)
		}
		return info
	}

	info.CPUShares = cgroupEnabled(mountPoint, "cpu.shares")
	if !quiet && !info.CPUShares {
		logrus.Warn("Your kernel does not support cgroup cpu shares")
	}

	info.CPUCfsPeriod = cgroupEnabled(mountPoint, "cpu.cfs_period_us")
	if !quiet && !info.CPUCfsPeriod {
		logrus.Warn("Your kernel does not support cgroup cfs period")
	}

	info.CPUCfsQuota = cgroupEnabled(mountPoint, "cpu.cfs_quota_us")
	if !quiet && !info.CPUCfsQuota {
		logrus.Warn("Your kernel does not support cgroup cfs quotas")
	}
	return info
}

func getSubsystemPath(c *configs.Cgroup, subsystem string) (string, error) {
	mountpoint, err := cgroups.FindCgroupMountpoint(subsystem)
	if err != nil {
		return "", err
	}

	initPath, err := cgroups.GetInitCgroupDir(subsystem)
	if err != nil {
		return "", err
	}
	// if pid 1 is systemd 226 or later, it will be in init.scope, not the root
	initPath = strings.TrimSuffix(filepath.Clean(initPath), "init.scope")

	slice := "system.slice"
	if c.Parent != "" {
		slice = c.Parent
	}

	slice, err = ExpandSlice(slice)
	if err != nil {
		return "", err
	}

	return filepath.Join(mountpoint, initPath, slice, getUnitName(c)), nil
}

// checkCgroupBlkioInfo reads the blkio information from the blkio cgroup mount point.
func checkCgroupBlkioInfo(quiet bool) cgroupBlkioInfo {
	mountPoint, err := cgroups.FindCgroupMountpoint("blkio")
	if err != nil {
		if !quiet {
			logrus.Warn(err)
		}
		return cgroupBlkioInfo{}
	}

	weight := cgroupEnabled(mountPoint, "blkio.weight")
	if !quiet && !weight {
		logrus.Warn("Your kernel does not support cgroup blkio weight")
	}

	weightDevice := cgroupEnabled(mountPoint, "blkio.weight_device")
	if !quiet && !weightDevice {
		logrus.Warn("Your kernel does not support cgroup blkio weight_device")
	}

	readBpsDevice := cgroupEnabled(mountPoint, "blkio.throttle.read_bps_device")
	if !quiet && !readBpsDevice {
		logrus.Warn("Your kernel does not support cgroup blkio throttle.read_bps_device")
	}

	writeBpsDevice := cgroupEnabled(mountPoint, "blkio.throttle.write_bps_device")
	if !quiet && !writeBpsDevice {
		logrus.Warn("Your kernel does not support cgroup blkio throttle.write_bps_device")
	}
	return cgroupBlkioInfo{
		BlkioWeight:         weight,
		BlkioWeightDevice:   weightDevice,
		BlkioReadBpsDevice:  readBpsDevice,
		BlkioWriteBpsDevice: writeBpsDevice,
	}
}

// New returns a new SysInfo, using the filesystem to detect which features
// the kernel supports. If `quiet` is `false` warnings are printed in logs
// whenever an error occurs or misconfigurations are present.
func New(quiet bool) *SysInfo {
	sysInfo := &SysInfo{}
	sysInfo.cgroupMemInfo = checkCgroupMem(quiet)
	sysInfo.cgroupCPUInfo = checkCgroupCPU(quiet)
	sysInfo.cgroupBlkioInfo = checkCgroupBlkioInfo(quiet)
	sysInfo.cgroupCpusetInfo = checkCgroupCpusetInfo(quiet)

	_, err := cgroups.FindCgroupMountpoint("devices")
	sysInfo.CgroupDevicesEnabled = err == nil

	sysInfo.IPv4ForwardingDisabled = !readProcBool("/proc/sys/net/ipv4/ip_forward")
	sysInfo.BridgeNfCallIptablesDisabled = !readProcBool("/proc/sys/net/bridge/bridge-nf-call-iptables")
	sysInfo.BridgeNfCallIP6tablesDisabled = !readProcBool("/proc/sys/net/bridge/bridge-nf-call-ip6tables")

	// Check if AppArmor is supported.
	if _, err := os.Stat("/sys/kernel/security/apparmor"); !os.IsNotExist(err) {
		sysInfo.AppArmor = true
	}

	// Check if Seccomp is supported, via CONFIG_SECCOMP.
	if _, _, err := syscall.RawSyscall(syscall.SYS_PRCTL, syscall.PR_GET_SECCOMP, 0, 0); err != syscall.EINVAL {
		// Make sure the kernel has CONFIG_SECCOMP_FILTER.
		if _, _, err := syscall.RawSyscall(syscall.SYS_PRCTL, syscall.PR_SET_SECCOMP, SeccompModeFilter, 0); err != syscall.EINVAL {
			sysInfo.Seccomp = true
		}
	}

	return sysInfo
}

// checkCgroupMem reads the memory information from the memory cgroup mount point.
func checkCgroupMem(quiet bool) cgroupMemInfo {
	mountPoint, err := cgroups.FindCgroupMountpoint("memory")
	if err != nil {
		if !quiet {
			logrus.Warnf("Your kernel does not support cgroup memory limit: %v", err)
		}
		return cgroupMemInfo{}
	}

	swapLimit := cgroupEnabled(mountPoint, "memory.memsw.limit_in_bytes")
	if !quiet && !swapLimit {
		logrus.Warn("Your kernel does not support swap memory limit.")
	}
	oomKillDisable := cgroupEnabled(mountPoint, "memory.oom_control")
	if !quiet && !oomKillDisable {
		logrus.Warnf("Your kernel does not support oom control.")
	}
	memorySwappiness := cgroupEnabled(mountPoint, "memory.swappiness")
	if !quiet && !memorySwappiness {
		logrus.Warnf("Your kernel does not support memory swappiness.")
	}

	return cgroupMemInfo{
		MemoryLimit:      true,
		SwapLimit:        swapLimit,
		OomKillDisable:   oomKillDisable,
		MemorySwappiness: memorySwappiness,
	}
}

// checkCgroupCpusetInfo reads the cpuset information from the cpuset cgroup mount point.
func checkCgroupCpusetInfo(quiet bool) cgroupCpusetInfo {
	mountPoint, err := cgroups.FindCgroupMountpoint("cpuset")
	if err != nil {
		if !quiet {
			logrus.Warn(err)
		}
		return cgroupCpusetInfo{}
	}

	cpus, err := ioutil.ReadFile(path.Join(mountPoint, "cpuset.cpus"))
	if err != nil {
		return cgroupCpusetInfo{}
	}

	mems, err := ioutil.ReadFile(path.Join(mountPoint, "cpuset.mems"))
	if err != nil {
		return cgroupCpusetInfo{}
	}

	return cgroupCpusetInfo{
		Cpuset: true,
		Cpus:   strings.TrimSpace(string(cpus)),
		Mems:   strings.TrimSpace(string(mems)),
	}
}

// checkCgroupCPU reads the cpu information from the cpu cgroup mount point.
func checkCgroupCPU(quiet bool) cgroupCPUInfo {
	mountPoint, err := cgroups.FindCgroupMountpoint("cpu")
	if err != nil {
		if !quiet {
			logrus.Warn(err)
		}
		return cgroupCPUInfo{}
	}

	cpuShares := cgroupEnabled(mountPoint, "cpu.shares")
	if !quiet && !cpuShares {
		logrus.Warn("Your kernel does not support cgroup cpu shares")
	}

	cpuCfsPeriod := cgroupEnabled(mountPoint, "cpu.cfs_period_us")
	if !quiet && !cpuCfsPeriod {
		logrus.Warn("Your kernel does not support cgroup cfs period")
	}

	cpuCfsQuota := cgroupEnabled(mountPoint, "cpu.cfs_quota_us")
	if !quiet && !cpuCfsQuota {
		logrus.Warn("Your kernel does not support cgroup cfs quotas")
	}
	return cgroupCPUInfo{
		CPUShares:    cpuShares,
		CPUCfsPeriod: cpuCfsPeriod,
		CPUCfsQuota:  cpuCfsQuota,
	}
}

func setupCGroups(partitions map[string]int64) error {
	subsystems, err := cgroups.GetAllSubsystems()
	if err != nil {
		return fmt.Errorf("error getting cgroup subsystems: %s", err)
	} else if len(subsystems) == 0 {
		return fmt.Errorf("failed to detect any cgroup subsystems")
	}

	for _, subsystem := range subsystems {
		if _, err := cgroups.FindCgroupMountpoint(subsystem); err == nil {
			// subsystem already mounted
			continue
		}
		path := filepath.Join(cgroupRoot, subsystem)
		if err := os.Mkdir(path, 0755); err != nil && !os.IsExist(err) {
			return fmt.Errorf("error creating %s cgroup directory: %s", subsystem, err)
		}
		if err := syscall.Mount("cgroup", path, "cgroup", 0, subsystem); err != nil {
			return fmt.Errorf("error mounting %s cgroup: %s", subsystem, err)
		}
	}

	for name, shares := range partitions {
		if err := createCGroupPartition(name, shares); err != nil {
			return err
		}
	}
	return nil
}

func getSubsystemPath(subsystem string, id string) (string, error) {
	var subsystemPath string
	systemSlice := "system.slice"
	// hack for finding proper mount point for shares
	// cpu shares are part of cpu group, but openlibcontainers does not support it
	if subsystem == "shares" {
		subsystem = "cpu"
	}
	groupPath, err := cgroups.FindCgroupMountpoint(subsystem)
	if err != nil {
		fmt.Fprintf(os.Stderr, "[WARNING] Could not find mount point for %v\n", subsystem)
		return "", err
	}
	if isHost(id) {
		if isRunningSystemd() {
			subsystemPath = filepath.Join(groupPath, systemSlice)
		} else {
			subsystemPath = groupPath
		}
		return subsystemPath, nil
	}

	if isFsCgroupParent(groupPath) {
		// default cgroupfs parent is used for container
		subsystemPath = filepath.Join(groupPath, "docker", id)
	} else {
		// cgroup is created under systemd.slice
		subsystemPath = filepath.Join(groupPath, systemSlice, "docker-"+id+".scope")
	}

	return subsystemPath, nil
}

// checkCgroupCpusetInfo reads the cpuset information from the cpuset cgroup mount point.
func checkCgroupCpusetInfo(quiet bool) cgroupCpusetInfo {
	_, err := cgroups.FindCgroupMountpoint("cpuset")
	if err != nil {
		if !quiet {
			logrus.Warn(err)
		}
		return cgroupCpusetInfo{}
	}

	return cgroupCpusetInfo{Cpuset: true}
}

func findCgroupRootAndDir(subsystem string) (string, string, error) {
	cgroupRoot, err := cgroups.FindCgroupMountpoint(subsystem)
	if err != nil {
		return "", "", err
	}

	cgroupDir, err := cgroups.GetThisCgroupDir(subsystem)
	if err != nil {
		return "", "", err
	}
	return cgroupRoot, cgroupDir, nil
}

func createCgroupdir(dir string) error {
	for _, subsystem := range []string{"memory", "cpu", "cpuset", "blkio"} {
		subsystemDir, err := cgroups.FindCgroupMountpoint(subsystem)
		if err != nil {
			return err
		}
		if err := os.MkdirAll(filepath.Join(subsystemDir, dir), 0700); err != nil {
			return err
		}
	}
	return nil
}

func (h *cgroupfsHelper) apply(subsystem, file, data string) error {
	subsystemDir, err := cgroups.FindCgroupMountpoint(subsystem)
	if err != nil {
		return err
	}
	if err := os.MkdirAll(filepath.Join(subsystemDir, h.cgroupDir), 0700); err != nil {
		return err
	}
	if err := writeFile(filepath.Join(subsystemDir, h.cgroupDir), file, data); err != nil {
		return err
	}
	return nil
}

func checkCgroupCpusetInfo(quiet bool) *cgroupCpusetInfo {
	info := &cgroupCpusetInfo{}
	_, err := cgroups.FindCgroupMountpoint("cpuset")
	if err != nil {
		if !quiet {
			logrus.Warn(err)
		}
		return info
	}

	info.Cpuset = true
	return info
}