blob: 53afbaddf1ff96c94ad5f44541e2231711ae63c5 [file] [log] [blame]
// +build linux
package fs
import (
"fmt"
"io/ioutil"
"path/filepath"
"strconv"
"strings"
"github.com/opencontainers/runc/libcontainer/cgroups"
"github.com/opencontainers/runc/libcontainer/configs"
"github.com/opencontainers/runc/libcontainer/system"
)
const (
cgroupCpuacctStat = "cpuacct.stat"
nanosecondsInSecond = 1000000000
)
var clockTicks = uint64(system.GetClockTicks())
type CpuacctGroup struct {
}
func (s *CpuacctGroup) Name() string {
return "cpuacct"
}
func (s *CpuacctGroup) Apply(d *cgroupData) error {
// we just want to join this group even though we don't set anything
if _, err := d.join("cpuacct"); err != nil && !cgroups.IsNotFound(err) {
return err
}
return nil
}
func (s *CpuacctGroup) Set(path string, cgroup *configs.Cgroup) error {
return nil
}
func (s *CpuacctGroup) Remove(d *cgroupData) error {
return removePath(d.path("cpuacct"))
}
func (s *CpuacctGroup) GetStats(path string, stats *cgroups.Stats) error {
userModeUsage, kernelModeUsage, err := getCpuUsageBreakdown(path)
if err != nil {
return err
}
totalUsage, err := getCgroupParamUint(path, "cpuacct.usage")
if err != nil {
return err
}
percpuUsage, err := getPercpuUsage(path)
if err != nil {
return err
}
stats.CpuStats.CpuUsage.TotalUsage = totalUsage
stats.CpuStats.CpuUsage.PercpuUsage = percpuUsage
stats.CpuStats.CpuUsage.UsageInUsermode = userModeUsage
stats.CpuStats.CpuUsage.UsageInKernelmode = kernelModeUsage
return nil
}
// Returns user and kernel usage breakdown in nanoseconds.
func getCpuUsageBreakdown(path string) (uint64, uint64, error) {
userModeUsage := uint64(0)
kernelModeUsage := uint64(0)
const (
userField = "user"
systemField = "system"
)
// Expected format:
// user <usage in ticks>
// system <usage in ticks>
data, err := ioutil.ReadFile(filepath.Join(path, cgroupCpuacctStat))
if err != nil {
return 0, 0, err
}
fields := strings.Fields(string(data))
if len(fields) != 4 {
return 0, 0, fmt.Errorf("failure - %s is expected to have 4 fields", filepath.Join(path, cgroupCpuacctStat))
}
if fields[0] != userField {
return 0, 0, fmt.Errorf("unexpected field %q in %q, expected %q", fields[0], cgroupCpuacctStat, userField)
}
if fields[2] != systemField {
return 0, 0, fmt.Errorf("unexpected field %q in %q, expected %q", fields[2], cgroupCpuacctStat, systemField)
}
if userModeUsage, err = strconv.ParseUint(fields[1], 10, 64); err != nil {
return 0, 0, err
}
if kernelModeUsage, err = strconv.ParseUint(fields[3], 10, 64); err != nil {
return 0, 0, err
}
return (userModeUsage * nanosecondsInSecond) / clockTicks, (kernelModeUsage * nanosecondsInSecond) / clockTicks, nil
}
func getPercpuUsage(path string) ([]uint64, error) {
percpuUsage := []uint64{}
data, err := ioutil.ReadFile(filepath.Join(path, "cpuacct.usage_percpu"))
if err != nil {
return percpuUsage, err
}
for _, value := range strings.Fields(string(data)) {
value, err := strconv.ParseUint(value, 10, 64)
if err != nil {
return percpuUsage, fmt.Errorf("Unable to convert param value to uint64: %s", err)
}
percpuUsage = append(percpuUsage, value)
}
return percpuUsage, nil
}