k3s/vendor/github.com/opencontainers/runc/libcontainer/cgroups/fs/cpu.go

118 lines
3.0 KiB
Go

// +build linux
package fs
import (
"bufio"
"fmt"
"os"
"path/filepath"
"strconv"
"github.com/opencontainers/runc/libcontainer/cgroups"
"github.com/opencontainers/runc/libcontainer/cgroups/fscommon"
"github.com/opencontainers/runc/libcontainer/configs"
)
type CpuGroup struct {
}
func (s *CpuGroup) Name() string {
return "cpu"
}
func (s *CpuGroup) Apply(path string, d *cgroupData) error {
// This might happen if we have no cpu cgroup mounted.
// Just do nothing and don't fail.
if path == "" {
return nil
}
if err := os.MkdirAll(path, 0755); err != nil {
return err
}
// We should set the real-Time group scheduling settings before moving
// in the process because if the process is already in SCHED_RR mode
// and no RT bandwidth is set, adding it will fail.
if err := s.SetRtSched(path, d.config); err != nil {
return err
}
// Since we are not using join(), we need to place the pid
// into the procs file unlike other subsystems.
return cgroups.WriteCgroupProc(path, d.pid)
}
func (s *CpuGroup) SetRtSched(path string, cgroup *configs.Cgroup) error {
if cgroup.Resources.CpuRtPeriod != 0 {
if err := fscommon.WriteFile(path, "cpu.rt_period_us", strconv.FormatUint(cgroup.Resources.CpuRtPeriod, 10)); err != nil {
return err
}
}
if cgroup.Resources.CpuRtRuntime != 0 {
if err := fscommon.WriteFile(path, "cpu.rt_runtime_us", strconv.FormatInt(cgroup.Resources.CpuRtRuntime, 10)); err != nil {
return err
}
}
return nil
}
func (s *CpuGroup) Set(path string, cgroup *configs.Cgroup) error {
if cgroup.Resources.CpuShares != 0 {
shares := cgroup.Resources.CpuShares
if err := fscommon.WriteFile(path, "cpu.shares", strconv.FormatUint(shares, 10)); err != nil {
return err
}
// read it back
sharesRead, err := fscommon.GetCgroupParamUint(path, "cpu.shares")
if err != nil {
return err
}
// ... and check
if shares > sharesRead {
return fmt.Errorf("the maximum allowed cpu-shares is %d", sharesRead)
} else if shares < sharesRead {
return fmt.Errorf("the minimum allowed cpu-shares is %d", sharesRead)
}
}
if cgroup.Resources.CpuPeriod != 0 {
if err := fscommon.WriteFile(path, "cpu.cfs_period_us", strconv.FormatUint(cgroup.Resources.CpuPeriod, 10)); err != nil {
return err
}
}
if cgroup.Resources.CpuQuota != 0 {
if err := fscommon.WriteFile(path, "cpu.cfs_quota_us", strconv.FormatInt(cgroup.Resources.CpuQuota, 10)); err != nil {
return err
}
}
return s.SetRtSched(path, cgroup)
}
func (s *CpuGroup) GetStats(path string, stats *cgroups.Stats) error {
f, err := os.Open(filepath.Join(path, "cpu.stat"))
if err != nil {
if os.IsNotExist(err) {
return nil
}
return err
}
defer f.Close()
sc := bufio.NewScanner(f)
for sc.Scan() {
t, v, err := fscommon.GetCgroupParamKeyValue(sc.Text())
if err != nil {
return err
}
switch t {
case "nr_periods":
stats.CpuStats.ThrottlingData.Periods = v
case "nr_throttled":
stats.CpuStats.ThrottlingData.ThrottledPeriods = v
case "throttled_time":
stats.CpuStats.ThrottlingData.ThrottledTime = v
}
}
return nil
}