mirror of https://github.com/k3s-io/k3s
77 lines
2.5 KiB
Go
77 lines
2.5 KiB
Go
/*
|
|
Copyright 2016 The Kubernetes Authors.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
*/
|
|
|
|
package util
|
|
|
|
import (
|
|
"path/filepath"
|
|
|
|
libcontainercgroups "github.com/opencontainers/runc/libcontainer/cgroups"
|
|
libcontainerutils "github.com/opencontainers/runc/libcontainer/utils"
|
|
)
|
|
|
|
// Forked from opencontainers/runc/libcontainer/cgroup/fs.Manager.GetPids()
|
|
func GetPids(cgroupPath string) ([]int, error) {
|
|
dir, err := getCgroupPath(cgroupPath)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return libcontainercgroups.GetPids(dir)
|
|
}
|
|
|
|
// getCgroupPath gets the file path to the "devices" subsystem of the desired cgroup.
|
|
// cgroupPath is the path in the cgroup hierarchy.
|
|
func getCgroupPath(cgroupPath string) (string, error) {
|
|
cgroupPath = libcontainerutils.CleanPath(cgroupPath)
|
|
|
|
mnt, root, err := libcontainercgroups.FindCgroupMountpointAndRoot("devices")
|
|
// If we didn't mount the subsystem, there is no point we make the path.
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
|
|
// If the cgroup name/path is absolute do not look relative to the cgroup of the init process.
|
|
if filepath.IsAbs(cgroupPath) {
|
|
// Sometimes subsystems can be mounted together as 'cpu,cpuacct'.
|
|
return filepath.Join(root, mnt, cgroupPath), nil
|
|
}
|
|
|
|
parentPath, err := getCgroupParentPath(mnt, root)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
|
|
return filepath.Join(parentPath, cgroupPath), nil
|
|
}
|
|
|
|
// getCgroupParentPath gets the parent filepath to this cgroup, for resolving relative cgroup paths.
|
|
func getCgroupParentPath(mountpoint, root string) (string, error) {
|
|
// Use GetThisCgroupDir instead of GetInitCgroupDir, because the creating
|
|
// process could in container and shared pid namespace with host, and
|
|
// /proc/1/cgroup could point to whole other world of cgroups.
|
|
initPath, err := libcontainercgroups.GetOwnCgroup("devices")
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
// This is needed for nested containers, because in /proc/self/cgroup we
|
|
// see paths from host, which don't exist in container.
|
|
relDir, err := filepath.Rel(root, initPath)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
return filepath.Join(mountpoint, relDir), nil
|
|
}
|