/usr/share/gocode/src/github.com/opencontainers/runc/libcontainer/cgroups/fs/cpuset.go is in golang-github-opencontainers-runc-dev 0.0.8+dfsg-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 | // +build linux
package fs
import (
"bytes"
"fmt"
"io/ioutil"
"os"
"path/filepath"
"strconv"
"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
}
root, err := getCgroupRoot()
if err != nil {
return err
}
if err := s.ensureParent(dir, root); 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 := writeFile(dir, "cgroup.procs", strconv.Itoa(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
}
|