Files
Nadeem Douba 752fc9b8ba Added support for v1 and v2 cgroups
No longer using a plugin to deploy solution
2023-07-03 09:58:18 -04:00

92 lines
2.4 KiB
Go

//go:build linux
/*
* Copyright (c) 2021, NVIDIA CORPORATION. All rights reserved.
*
* 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 cgroup
import (
"bufio"
"fmt"
"os"
"path/filepath"
"strings"
"github.com/opencontainers/runtime-spec/specs-go"
)
type DeviceRule = specs.LinuxDeviceCgroup
type Interface interface {
GetDeviceCGroupMountPath(procRootPath string, pid int) (string, string, error)
GetDeviceCGroupRootPath(procRootPath string, prefix string, pid int) (string, error)
AddDeviceRules(cgroupPath string, devices []DeviceRule) error
}
func New(version int) (Interface, error) {
switch version {
case 1:
return &cgroupv1{}, nil
case 2:
return &cgroupv2{}, nil
default:
return nil, fmt.Errorf("invalid version")
}
}
type cgroupv1 struct{}
type cgroupv2 struct{}
var _ Interface = (*cgroupv1)(nil)
var _ Interface = (*cgroupv2)(nil)
// GetDeviceCGroupVersion returns the version of linux cgroups in use
func GetDeviceCGroupVersion(rootPath string, pid int) (int, error) {
// Open the pid's cgroup file in /proc.
path := fmt.Sprintf(filepath.Join(rootPath, "proc", "%v", "cgroup"), pid)
file, err := os.Open(path)
if err != nil {
return -1, fmt.Errorf("failed to open cgroup path for pid '%d': %v", pid, err)
}
defer file.Close()
// Create a scanner to loop through the file's contents.
scanner := bufio.NewScanner(file)
scanner.Split(bufio.ScanLines)
// Loop through the file looking for either a 'devices' or a '' (i.e. unified) entry
found := make(map[string]bool)
for scanner.Scan() {
parts := strings.SplitN(scanner.Text(), ":", 3)
if len(parts) != 3 {
return -1, fmt.Errorf("malformed cgroup entry: %v", scanner.Text())
}
found[parts[1]] = true
}
// If a 'devices' entry was found, return version 1.
if found["devices"] {
return 1, nil
}
// If a '', (i.e. 'unified') entry was found, return version 2.
if found[""] {
return 2, nil
}
return -1, fmt.Errorf("no devices or unified cgroup entries found")
}