You've already forked runc
mirror of
https://github.com/opencontainers/runc.git
synced 2025-08-01 05:06:52 +03:00
c3b0b13fe9
Function defaultPath always parses /proc/self/cgroup, but the resulting value is not always used. Avoid unnecessary reading/parsing by moving the code to just before its use. Modify the test case accordingly. [v2: test: use UnifiedMountpoint, skip test if not on v2] Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
106 lines
2.9 KiB
Go
106 lines
2.9 KiB
Go
/*
|
|
Copyright The containerd 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 fs2
|
|
|
|
import (
|
|
"bufio"
|
|
"io"
|
|
"os"
|
|
"path/filepath"
|
|
"strings"
|
|
|
|
"github.com/opencontainers/runc/libcontainer/configs"
|
|
libcontainerUtils "github.com/opencontainers/runc/libcontainer/utils"
|
|
"github.com/pkg/errors"
|
|
)
|
|
|
|
const UnifiedMountpoint = "/sys/fs/cgroup"
|
|
|
|
func defaultDirPath(c *configs.Cgroup) (string, error) {
|
|
if (c.Name != "" || c.Parent != "") && c.Path != "" {
|
|
return "", errors.Errorf("cgroup: either Path or Name and Parent should be used, got %+v", c)
|
|
}
|
|
if len(c.Paths) != 0 {
|
|
// never set by specconv
|
|
return "", errors.Errorf("cgroup: Paths is unsupported, use Path, got %+v", c)
|
|
}
|
|
|
|
// XXX: Do not remove this code. Path safety is important! -- cyphar
|
|
cgPath := libcontainerUtils.CleanPath(c.Path)
|
|
cgParent := libcontainerUtils.CleanPath(c.Parent)
|
|
cgName := libcontainerUtils.CleanPath(c.Name)
|
|
|
|
return _defaultDirPath(UnifiedMountpoint, cgPath, cgParent, cgName)
|
|
}
|
|
|
|
func _defaultDirPath(root, cgPath, cgParent, cgName string) (string, error) {
|
|
if (cgName != "" || cgParent != "") && cgPath != "" {
|
|
return "", errors.New("cgroup: either Path or Name and Parent should be used")
|
|
}
|
|
innerPath := cgPath
|
|
if innerPath == "" {
|
|
innerPath = filepath.Join(cgParent, cgName)
|
|
}
|
|
if filepath.IsAbs(innerPath) {
|
|
return filepath.Join(root, innerPath), nil
|
|
}
|
|
|
|
ownCgroup, err := parseCgroupFile("/proc/self/cgroup")
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
// The current user scope most probably has tasks in it already,
|
|
// making it impossible to enable controllers for its sub-cgroup.
|
|
// A parent cgroup (with no tasks in it) is what we need.
|
|
ownCgroup = filepath.Dir(ownCgroup)
|
|
|
|
return filepath.Join(root, ownCgroup, innerPath), nil
|
|
}
|
|
|
|
// parseCgroupFile parses /proc/PID/cgroup file and return string
|
|
func parseCgroupFile(path string) (string, error) {
|
|
f, err := os.Open(path)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
defer f.Close()
|
|
return parseCgroupFromReader(f)
|
|
}
|
|
|
|
func parseCgroupFromReader(r io.Reader) (string, error) {
|
|
var (
|
|
s = bufio.NewScanner(r)
|
|
)
|
|
for s.Scan() {
|
|
var (
|
|
text = s.Text()
|
|
parts = strings.SplitN(text, ":", 3)
|
|
)
|
|
if len(parts) < 3 {
|
|
return "", errors.Errorf("invalid cgroup entry: %q", text)
|
|
}
|
|
// text is like "0::/user.slice/user-1001.slice/session-1.scope"
|
|
if parts[0] == "0" && parts[1] == "" {
|
|
return parts[2], nil
|
|
}
|
|
}
|
|
if err := s.Err(); err != nil {
|
|
return "", err
|
|
}
|
|
return "", errors.New("cgroup path not found")
|
|
}
|