From a031b83a09a8628435317a03f199cdc18b78262f Mon Sep 17 00:00:00 2001 From: Matthew Heon Date: Wed, 1 Nov 2017 11:24:59 -0400 Subject: Initial checkin from CRI-O repo Signed-off-by: Matthew Heon --- vendor/github.com/containerd/cgroups/utils.go | 280 ++++++++++++++++++++++++++ 1 file changed, 280 insertions(+) create mode 100644 vendor/github.com/containerd/cgroups/utils.go (limited to 'vendor/github.com/containerd/cgroups/utils.go') diff --git a/vendor/github.com/containerd/cgroups/utils.go b/vendor/github.com/containerd/cgroups/utils.go new file mode 100644 index 000000000..d5c7230a0 --- /dev/null +++ b/vendor/github.com/containerd/cgroups/utils.go @@ -0,0 +1,280 @@ +package cgroups + +import ( + "bufio" + "fmt" + "io" + "io/ioutil" + "os" + "path/filepath" + "strconv" + "strings" + "time" + + units "github.com/docker/go-units" + specs "github.com/opencontainers/runtime-spec/specs-go" +) + +var isUserNS = runningInUserNS() + +// runningInUserNS detects whether we are currently running in a user namespace. +// Copied from github.com/lxc/lxd/shared/util.go +func runningInUserNS() bool { + file, err := os.Open("/proc/self/uid_map") + if err != nil { + // This kernel-provided file only exists if user namespaces are supported + return false + } + defer file.Close() + + buf := bufio.NewReader(file) + l, _, err := buf.ReadLine() + if err != nil { + return false + } + + line := string(l) + var a, b, c int64 + fmt.Sscanf(line, "%d %d %d", &a, &b, &c) + /* + * We assume we are in the initial user namespace if we have a full + * range - 4294967295 uids starting at uid 0. + */ + if a == 0 && b == 0 && c == 4294967295 { + return false + } + return true +} + +// defaults returns all known groups +func defaults(root string) ([]Subsystem, error) { + h, err := NewHugetlb(root) + if err != nil && !os.IsNotExist(err) { + return nil, err + } + s := []Subsystem{ + NewNamed(root, "systemd"), + NewFreezer(root), + NewPids(root), + NewNetCls(root), + NewNetPrio(root), + NewPerfEvent(root), + NewCputset(root), + NewCpu(root), + NewCpuacct(root), + NewMemory(root), + NewBlkio(root), + } + // only add the devices cgroup if we are not in a user namespace + // because modifications are not allowed + if !isUserNS { + s = append(s, NewDevices(root)) + } + // add the hugetlb cgroup if error wasn't due to missing hugetlb + // cgroup support on the host + if err == nil { + s = append(s, h) + } + return s, nil +} + +// remove will remove a cgroup path handling EAGAIN and EBUSY errors and +// retrying the remove after a exp timeout +func remove(path string) error { + delay := 10 * time.Millisecond + for i := 0; i < 5; i++ { + if i != 0 { + time.Sleep(delay) + delay *= 2 + } + if err := os.RemoveAll(path); err == nil { + return nil + } + } + return fmt.Errorf("cgroups: unable to remove path %q", path) +} + +// readPids will read all the pids in a cgroup by the provided path +func readPids(path string, subsystem Name) ([]Process, error) { + f, err := os.Open(filepath.Join(path, cgroupProcs)) + if err != nil { + return nil, err + } + defer f.Close() + var ( + out []Process + s = bufio.NewScanner(f) + ) + for s.Scan() { + if t := s.Text(); t != "" { + pid, err := strconv.Atoi(t) + if err != nil { + return nil, err + } + out = append(out, Process{ + Pid: pid, + Subsystem: subsystem, + Path: path, + }) + } + } + return out, nil +} + +func hugePageSizes() ([]string, error) { + var ( + pageSizes []string + sizeList = []string{"B", "kB", "MB", "GB", "TB", "PB"} + ) + files, err := ioutil.ReadDir("/sys/kernel/mm/hugepages") + if err != nil { + return nil, err + } + for _, st := range files { + nameArray := strings.Split(st.Name(), "-") + pageSize, err := units.RAMInBytes(nameArray[1]) + if err != nil { + return nil, err + } + pageSizes = append(pageSizes, units.CustomSize("%g%s", float64(pageSize), 1024.0, sizeList)) + } + return pageSizes, nil +} + +func readUint(path string) (uint64, error) { + v, err := ioutil.ReadFile(path) + if err != nil { + return 0, err + } + return parseUint(strings.TrimSpace(string(v)), 10, 64) +} + +func parseUint(s string, base, bitSize int) (uint64, error) { + v, err := strconv.ParseUint(s, base, bitSize) + if err != nil { + intValue, intErr := strconv.ParseInt(s, base, bitSize) + // 1. Handle negative values greater than MinInt64 (and) + // 2. Handle negative values lesser than MinInt64 + if intErr == nil && intValue < 0 { + return 0, nil + } else if intErr != nil && + intErr.(*strconv.NumError).Err == strconv.ErrRange && + intValue < 0 { + return 0, nil + } + return 0, err + } + return v, nil +} + +func parseKV(raw string) (string, uint64, error) { + parts := strings.Fields(raw) + switch len(parts) { + case 2: + v, err := parseUint(parts[1], 10, 64) + if err != nil { + return "", 0, err + } + return parts[0], v, nil + default: + return "", 0, ErrInvalidFormat + } +} + +func parseCgroupFile(path string) (map[string]string, error) { + f, err := os.Open(path) + if err != nil { + return nil, err + } + defer f.Close() + return parseCgroupFromReader(f) +} + +func parseCgroupFromReader(r io.Reader) (map[string]string, error) { + var ( + cgroups = make(map[string]string) + s = bufio.NewScanner(r) + ) + for s.Scan() { + if err := s.Err(); err != nil { + return nil, err + } + var ( + text = s.Text() + parts = strings.SplitN(text, ":", 3) + ) + if len(parts) < 3 { + return nil, fmt.Errorf("invalid cgroup entry: %q", text) + } + for _, subs := range strings.Split(parts[1], ",") { + if subs != "" { + cgroups[subs] = parts[2] + } + } + } + return cgroups, nil +} + +func getCgroupDestination(subsystem string) (string, error) { + f, err := os.Open("/proc/self/mountinfo") + if err != nil { + return "", err + } + defer f.Close() + s := bufio.NewScanner(f) + for s.Scan() { + if err := s.Err(); err != nil { + return "", err + } + fields := strings.Fields(s.Text()) + for _, opt := range strings.Split(fields[len(fields)-1], ",") { + if opt == subsystem { + return fields[3], nil + } + } + } + return "", ErrNoCgroupMountDestination +} + +func pathers(subystems []Subsystem) []pather { + var out []pather + for _, s := range subystems { + if p, ok := s.(pather); ok { + out = append(out, p) + } + } + return out +} + +func initializeSubsystem(s Subsystem, path Path, resources *specs.LinuxResources) error { + if c, ok := s.(creator); ok { + p, err := path(s.Name()) + if err != nil { + return err + } + if err := c.Create(p, resources); err != nil { + return err + } + } else if c, ok := s.(pather); ok { + p, err := path(s.Name()) + if err != nil { + return err + } + // do the default create if the group does not have a custom one + if err := os.MkdirAll(c.Path(p), defaultDirPerm); err != nil { + return err + } + } + return nil +} + +func cleanPath(path string) string { + if path == "" { + return "" + } + path = filepath.Clean(path) + if !filepath.IsAbs(path) { + path, _ = filepath.Rel(string(os.PathSeparator), filepath.Clean(string(os.PathSeparator)+path)) + } + return filepath.Clean(path) +} -- cgit v1.2.3-54-g00ecf