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
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
|
package cgroups
import (
"bytes"
"errors"
"fmt"
"io/ioutil"
"os"
"path/filepath"
"strconv"
"strings"
)
var TestMode bool
func cleanString(s string) string {
return strings.Trim(s, "\n")
}
func readAcct(ctr *CgroupControl, name string) (uint64, error) {
p := filepath.Join(ctr.getCgroupv1Path(CPUAcct), name)
return readFileAsUint64(p)
}
func readAcctList(ctr *CgroupControl, name string) ([]uint64, error) {
p := filepath.Join(ctr.getCgroupv1Path(CPUAcct), name)
data, err := ioutil.ReadFile(p)
if err != nil {
return nil, fmt.Errorf("reading %s: %w", p, err)
}
r := []uint64{}
for _, s := range strings.Split(string(data), " ") {
s = cleanString(s)
if s == "" {
break
}
v, err := strconv.ParseUint(s, 10, 64)
if err != nil {
return nil, fmt.Errorf("parsing %s: %w", s, err)
}
r = append(r, v)
}
return r, nil
}
// GetSystemCPUUsage returns the system usage for all the cgroups
func GetSystemCPUUsage() (uint64, error) {
cgroupv2, err := IsCgroup2UnifiedMode()
if err != nil {
return 0, err
}
if !cgroupv2 {
p := filepath.Join(cgroupRoot, CPUAcct, "cpuacct.usage")
return readFileAsUint64(p)
}
files, err := ioutil.ReadDir(cgroupRoot)
if err != nil {
return 0, err
}
var total uint64
for _, file := range files {
if !file.IsDir() {
continue
}
p := filepath.Join(cgroupRoot, file.Name(), "cpu.stat")
values, err := readCgroup2MapPath(p)
if err != nil {
return 0, err
}
if val, found := values["usage_usec"]; found {
v, err := strconv.ParseUint(cleanString(val[0]), 10, 64)
if err != nil {
return 0, err
}
total += v * 1000
}
}
return total, nil
}
func cpusetCopyFileFromParent(dir, file string, cgroupv2 bool) ([]byte, error) {
if dir == cgroupRoot {
return nil, fmt.Errorf("could not find parent to initialize cpuset %s", file)
}
path := filepath.Join(dir, file)
parentPath := path
if cgroupv2 {
parentPath = fmt.Sprintf("%s.effective", parentPath)
}
data, err := ioutil.ReadFile(parentPath)
if err != nil {
return nil, fmt.Errorf("open %s: %w", path, err)
}
if strings.Trim(string(data), "\n") != "" {
return data, nil
}
data, err = cpusetCopyFileFromParent(filepath.Dir(dir), file, cgroupv2)
if err != nil {
return nil, err
}
if err := ioutil.WriteFile(path, data, 0o644); err != nil {
return nil, fmt.Errorf("write %s: %w", path, err)
}
return data, nil
}
func cpusetCopyFromParent(path string, cgroupv2 bool) error {
for _, file := range []string{"cpuset.cpus", "cpuset.mems"} {
if _, err := cpusetCopyFileFromParent(path, file, cgroupv2); err != nil {
return err
}
}
return nil
}
// createCgroupv2Path creates the cgroupv2 path and enables all the available controllers
func createCgroupv2Path(path string) (deferredError error) {
if !strings.HasPrefix(path, cgroupRoot+"/") {
return fmt.Errorf("invalid cgroup path %s", path)
}
content, err := ioutil.ReadFile(cgroupRoot + "/cgroup.controllers")
if err != nil {
return err
}
ctrs := bytes.Fields(content)
res := append([]byte("+"), bytes.Join(ctrs, []byte(" +"))...)
current := "/sys/fs"
elements := strings.Split(path, "/")
for i, e := range elements[3:] {
current = filepath.Join(current, e)
if i > 0 {
if err := os.Mkdir(current, 0o755); err != nil {
if !os.IsExist(err) {
return err
}
} else {
// If the directory was created, be sure it is not left around on errors.
defer func() {
if deferredError != nil {
os.Remove(current)
}
}()
}
}
// We enable the controllers for all the path components except the last one. It is not allowed to add
// PIDs if there are already enabled controllers.
if i < len(elements[3:])-1 {
if err := ioutil.WriteFile(filepath.Join(current, "cgroup.subtree_control"), res, 0o755); err != nil {
return err
}
}
}
return nil
}
func (c *CgroupControl) createCgroupDirectory(controller string) (bool, error) {
cPath := c.getCgroupv1Path(controller)
_, err := os.Stat(cPath)
if err == nil {
return false, nil
}
if !errors.Is(err, os.ErrNotExist) {
return false, err
}
if err := os.MkdirAll(cPath, 0o755); err != nil {
return false, fmt.Errorf("error creating cgroup for %s: %w", controller, err)
}
return true, nil
}
|
