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-rw-r--r--vendor/github.com/containerd/cgroups/cpuset.go139
1 files changed, 139 insertions, 0 deletions
diff --git a/vendor/github.com/containerd/cgroups/cpuset.go b/vendor/github.com/containerd/cgroups/cpuset.go
new file mode 100644
index 000000000..f0f95f569
--- /dev/null
+++ b/vendor/github.com/containerd/cgroups/cpuset.go
@@ -0,0 +1,139 @@
+package cgroups
+
+import (
+ "bytes"
+ "fmt"
+ "io/ioutil"
+ "os"
+ "path/filepath"
+
+ specs "github.com/opencontainers/runtime-spec/specs-go"
+)
+
+func NewCputset(root string) *cpusetController {
+ return &cpusetController{
+ root: filepath.Join(root, string(Cpuset)),
+ }
+}
+
+type cpusetController struct {
+ root string
+}
+
+func (c *cpusetController) Name() Name {
+ return Cpuset
+}
+
+func (c *cpusetController) Path(path string) string {
+ return filepath.Join(c.root, path)
+}
+
+func (c *cpusetController) Create(path string, resources *specs.LinuxResources) error {
+ if err := c.ensureParent(c.Path(path), c.root); err != nil {
+ return err
+ }
+ if err := os.MkdirAll(c.Path(path), defaultDirPerm); err != nil {
+ return err
+ }
+ if err := c.copyIfNeeded(c.Path(path), filepath.Dir(c.Path(path))); err != nil {
+ return err
+ }
+ if resources.CPU != nil {
+ for _, t := range []struct {
+ name string
+ value *string
+ }{
+ {
+ name: "cpus",
+ value: &resources.CPU.Cpus,
+ },
+ {
+ name: "mems",
+ value: &resources.CPU.Mems,
+ },
+ } {
+ if t.value != nil {
+ if err := ioutil.WriteFile(
+ filepath.Join(c.Path(path), fmt.Sprintf("cpuset.%s", t.name)),
+ []byte(*t.value),
+ defaultFilePerm,
+ ); err != nil {
+ return err
+ }
+ }
+ }
+ }
+ return nil
+}
+
+func (c *cpusetController) getValues(path string) (cpus []byte, mems []byte, err error) {
+ if cpus, err = ioutil.ReadFile(filepath.Join(path, "cpuset.cpus")); err != nil && !os.IsNotExist(err) {
+ return
+ }
+ if mems, err = ioutil.ReadFile(filepath.Join(path, "cpuset.mems")); err != nil && !os.IsNotExist(err) {
+ 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 (c *cpusetController) ensureParent(current, root string) error {
+ parent := filepath.Dir(current)
+ if _, err := filepath.Rel(root, parent); err != nil {
+ return nil
+ }
+ // Avoid infinite recursion.
+ if parent == current {
+ return fmt.Errorf("cpuset: cgroup parent path outside cgroup root")
+ }
+ if cleanPath(parent) != root {
+ if err := c.ensureParent(parent, root); err != nil {
+ return err
+ }
+ }
+ if err := os.MkdirAll(current, defaultDirPerm); err != nil {
+ return err
+ }
+ return c.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 (c *cpusetController) copyIfNeeded(current, parent string) error {
+ var (
+ err error
+ currentCpus, currentMems []byte
+ parentCpus, parentMems []byte
+ )
+ if currentCpus, currentMems, err = c.getValues(current); err != nil {
+ return err
+ }
+ if parentCpus, parentMems, err = c.getValues(parent); err != nil {
+ return err
+ }
+ if isEmpty(currentCpus) {
+ if err := ioutil.WriteFile(
+ filepath.Join(current, "cpuset.cpus"),
+ parentCpus,
+ defaultFilePerm,
+ ); err != nil {
+ return err
+ }
+ }
+ if isEmpty(currentMems) {
+ if err := ioutil.WriteFile(
+ filepath.Join(current, "cpuset.mems"),
+ parentMems,
+ defaultFilePerm,
+ ); err != nil {
+ return err
+ }
+ }
+ return nil
+}
+
+func isEmpty(b []byte) bool {
+ return len(bytes.Trim(b, "\n")) == 0
+}