Remove unused runc files

We no longer use runc code to read network I/O usage. This lets
us remove a lot of vendored code.

Signed-off-by: Matthew Heon <matthew.heon@gmail.com>

Closes: #425
Approved by: rhatdan

vendor/github.com/opencontainers/runc/libcontainer/cgroups/fs/cpuset.go

@@ -1,163 +0,0 @@
-// +build linux
-
-package fs
-
-import (
-	"bytes"
-	"fmt"
-	"io/ioutil"
-	"os"
-	"path/filepath"
-
-	"github.com/opencontainers/runc/libcontainer/cgroups"
-	"github.com/opencontainers/runc/libcontainer/configs"
-	libcontainerUtils "github.com/opencontainers/runc/libcontainer/utils"
-)
-
-type CpusetGroup struct {
-}
-
-func (s *CpusetGroup) Name() string {
-	return "cpuset"
-}
-
-func (s *CpusetGroup) Apply(d *cgroupData) error {
-	dir, err := d.path("cpuset")
-	if err != nil && !cgroups.IsNotFound(err) {
-		return err
-	}
-	return s.ApplyDir(dir, d.config, d.pid)
-}
-
-func (s *CpusetGroup) Set(path string, cgroup *configs.Cgroup) error {
-	if cgroup.Resources.CpusetCpus != "" {
-		if err := writeFile(path, "cpuset.cpus", cgroup.Resources.CpusetCpus); err != nil {
-			return err
-		}
-	}
-	if cgroup.Resources.CpusetMems != "" {
-		if err := writeFile(path, "cpuset.mems", cgroup.Resources.CpusetMems); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-func (s *CpusetGroup) Remove(d *cgroupData) error {
-	return removePath(d.path("cpuset"))
-}
-
-func (s *CpusetGroup) GetStats(path string, stats *cgroups.Stats) error {
-	return nil
-}
-
-func (s *CpusetGroup) ApplyDir(dir string, cgroup *configs.Cgroup, pid int) error {
-	// This might happen if we have no cpuset cgroup mounted.
-	// Just do nothing and don't fail.
-	if dir == "" {
-		return nil
-	}
-	mountInfo, err := ioutil.ReadFile("/proc/self/mountinfo")
-	if err != nil {
-		return err
-	}
-	root := filepath.Dir(cgroups.GetClosestMountpointAncestor(dir, string(mountInfo)))
-	// 'ensureParent' start with parent because we don't want to
-	// explicitly inherit from parent, it could conflict with
-	// 'cpuset.cpu_exclusive'.
-	if err := s.ensureParent(filepath.Dir(dir), root); err != nil {
-		return err
-	}
-	if err := os.MkdirAll(dir, 0755); err != nil {
-		return err
-	}
-	// We didn't inherit cpuset configs from parent, but we have
-	// to ensure cpuset configs are set before moving task into the
-	// cgroup.
-	// The logic is, if user specified cpuset configs, use these
-	// specified configs, otherwise, inherit from parent. This makes
-	// cpuset configs work correctly with 'cpuset.cpu_exclusive', and
-	// keep backward compatbility.
-	if err := s.ensureCpusAndMems(dir, cgroup); err != nil {
-		return err
-	}
-
-	// because we are not using d.join we need to place the pid into the procs file
-	// unlike the other subsystems
-	if err := cgroups.WriteCgroupProc(dir, pid); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func (s *CpusetGroup) getSubsystemSettings(parent string) (cpus []byte, mems []byte, err error) {
-	if cpus, err = ioutil.ReadFile(filepath.Join(parent, "cpuset.cpus")); err != nil {
-		return
-	}
-	if mems, err = ioutil.ReadFile(filepath.Join(parent, "cpuset.mems")); err != nil {
-		return
-	}
-	return cpus, mems, nil
-}
-
-// ensureParent makes sure that the parent directory of current is created
-// and populated with the proper cpus and mems files copied from
-// it's parent.
-func (s *CpusetGroup) ensureParent(current, root string) error {
-	parent := filepath.Dir(current)
-	if libcontainerUtils.CleanPath(parent) == root {
-		return nil
-	}
-	// Avoid infinite recursion.
-	if parent == current {
-		return fmt.Errorf("cpuset: cgroup parent path outside cgroup root")
-	}
-	if err := s.ensureParent(parent, root); err != nil {
-		return err
-	}
-	if err := os.MkdirAll(current, 0755); err != nil {
-		return err
-	}
-	return s.copyIfNeeded(current, parent)
-}
-
-// copyIfNeeded copies the cpuset.cpus and cpuset.mems from the parent
-// directory to the current directory if the file's contents are 0
-func (s *CpusetGroup) copyIfNeeded(current, parent string) error {
-	var (
-		err                      error
-		currentCpus, currentMems []byte
-		parentCpus, parentMems   []byte
-	)
-
-	if currentCpus, currentMems, err = s.getSubsystemSettings(current); err != nil {
-		return err
-	}
-	if parentCpus, parentMems, err = s.getSubsystemSettings(parent); err != nil {
-		return err
-	}
-
-	if s.isEmpty(currentCpus) {
-		if err := writeFile(current, "cpuset.cpus", string(parentCpus)); err != nil {
-			return err
-		}
-	}
-	if s.isEmpty(currentMems) {
-		if err := writeFile(current, "cpuset.mems", string(parentMems)); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-func (s *CpusetGroup) isEmpty(b []byte) bool {
-	return len(bytes.Trim(b, "\n")) == 0
-}
-
-func (s *CpusetGroup) ensureCpusAndMems(path string, cgroup *configs.Cgroup) error {
-	if err := s.Set(path, cgroup); err != nil {
-		return err
-	}
-	return s.copyIfNeeded(path, filepath.Dir(path))
-}