package sysinfo import ( "io/ioutil" "os" "path" "strings" "github.com/Sirupsen/logrus" "github.com/docker/libcontainer/cgroups" ) // New returns a new SysInfo, using the filesystem to detect which features the kernel supports. func New(quiet bool) *SysInfo { sysInfo := &SysInfo{} sysInfo.cgroupMemInfo = checkCgroupMem(quiet) sysInfo.cgroupCpuInfo = checkCgroupCpu(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 } return sysInfo } 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.") } 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.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 cgroupEnabled(mountPoint, name string) bool { _, err := os.Stat(path.Join(mountPoint, name)) return err == nil } func readProcBool(path string) bool { val, err := ioutil.ReadFile(path) if err != nil { return false } return strings.TrimSpace(string(val)) == "1" }