k3s/vendor/github.com/containerd/cgroups/cpuacct.go

122 lines
2.8 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 cgroups
import (
"fmt"
"io/ioutil"
"path/filepath"
"strconv"
"strings"
)
const nanosecondsInSecond = 1000000000
var clockTicks = getClockTicks()
func NewCpuacct(root string) *cpuacctController {
return &cpuacctController{
root: filepath.Join(root, string(Cpuacct)),
}
}
type cpuacctController struct {
root string
}
func (c *cpuacctController) Name() Name {
return Cpuacct
}
func (c *cpuacctController) Path(path string) string {
return filepath.Join(c.root, path)
}
func (c *cpuacctController) Stat(path string, stats *Metrics) error {
user, kernel, err := c.getUsage(path)
if err != nil {
return err
}
total, err := readUint(filepath.Join(c.Path(path), "cpuacct.usage"))
if err != nil {
return err
}
percpu, err := c.percpuUsage(path)
if err != nil {
return err
}
stats.CPU.Usage.Total = total
stats.CPU.Usage.User = user
stats.CPU.Usage.Kernel = kernel
stats.CPU.Usage.PerCPU = percpu
return nil
}
func (c *cpuacctController) percpuUsage(path string) ([]uint64, error) {
var usage []uint64
data, err := ioutil.ReadFile(filepath.Join(c.Path(path), "cpuacct.usage_percpu"))
if err != nil {
return nil, err
}
for _, v := range strings.Fields(string(data)) {
u, err := strconv.ParseUint(v, 10, 64)
if err != nil {
return nil, err
}
usage = append(usage, u)
}
return usage, nil
}
func (c *cpuacctController) getUsage(path string) (user uint64, kernel uint64, err error) {
statPath := filepath.Join(c.Path(path), "cpuacct.stat")
data, err := ioutil.ReadFile(statPath)
if err != nil {
return 0, 0, err
}
fields := strings.Fields(string(data))
if len(fields) != 4 {
return 0, 0, fmt.Errorf("%q is expected to have 4 fields", statPath)
}
for _, t := range []struct {
index int
name string
value *uint64
}{
{
index: 0,
name: "user",
value: &user,
},
{
index: 2,
name: "system",
value: &kernel,
},
} {
if fields[t.index] != t.name {
return 0, 0, fmt.Errorf("expected field %q but found %q in %q", t.name, fields[t.index], statPath)
}
v, err := strconv.ParseUint(fields[t.index+1], 10, 64)
if err != nil {
return 0, 0, err
}
*t.value = v
}
return (user * nanosecondsInSecond) / clockTicks, (kernel * nanosecondsInSecond) / clockTicks, nil
}