// Copyright 2014 Google Inc. 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 libcontainer
import (
"fmt"
info "github.com/google/cadvisor/info/v1"
"github.com/opencontainers/runc/libcontainer/cgroups"
"github.com/google/cadvisor/container"
fs "github.com/opencontainers/runc/libcontainer/cgroups/fs"
fs2 "github.com/opencontainers/runc/libcontainer/cgroups/fs2"
configs "github.com/opencontainers/runc/libcontainer/configs"
"k8s.io/klog/v2"
)
// GetCgroupSubsystems returns information about the cgroup subsystems that are
// of interest as a map of cgroup controllers to their mount points.
// For example, "cpu" -> "/sys/fs/cgroup/cpu".
//
// The incudeMetrics arguments specifies which metrics are requested,
// and is used to filter out some cgroups and their mounts. If nil,
// all supported cgroup subsystems are included.
//
// For cgroup v2, includedMetrics argument is unused, the only map key is ""
// (empty string), and the value is the unified cgroup mount point.
func GetCgroupSubsystems(includedMetrics container.MetricSet) (map[string]string, error) {
if cgroups.IsCgroup2UnifiedMode() {
return map[string]string{"": fs2.UnifiedMountpoint}, nil
}
// Get all cgroup mounts.
allCgroups, err := cgroups.GetCgroupMounts(true)
if err != nil {
return nil, err
}
return getCgroupSubsystemsHelper(allCgroups, includedMetrics)
}
func getCgroupSubsystemsHelper(allCgroups []cgroups.Mount, includedMetrics container.MetricSet) (map[string]string, error) {
if len(allCgroups) == 0 {
return nil, fmt.Errorf("failed to find cgroup mounts")
}
// Trim the mounts to only the subsystems we care about.
mountPoints := make(map[string]string, len(allCgroups))
for _, mount := range allCgroups {
for _, subsystem := range mount.Subsystems {
if !needSubsys(subsystem, includedMetrics) {
continue
}
if _, ok := mountPoints[subsystem]; ok {
// duplicate mount for this subsystem; use the first one we saw
klog.V(5).Infof("skipping %s, already using mount at %s", mount.Mountpoint, mountPoints[subsystem])
continue
}
mountPoints[subsystem] = mount.Mountpoint
}
}
return mountPoints, nil
}
// A map of cgroup subsystems we support listing (should be the minimal set
// we need stats from) to a respective MetricKind.
var supportedSubsystems = map[string]container.MetricKind{
"cpu": container.CpuUsageMetrics,
"cpuacct": container.CpuUsageMetrics,
"memory": container.MemoryUsageMetrics,
"hugetlb": container.HugetlbUsageMetrics,
"pids": container.ProcessMetrics,
"cpuset": container.CPUSetMetrics,
"blkio": container.DiskIOMetrics,
"io": container.DiskIOMetrics,
"devices": "",
"perf_event": container.PerfMetrics,
}
// Check if this cgroup subsystem/controller is of use.
func needSubsys(name string, metrics container.MetricSet) bool {
// Check if supported.
metric, supported := supportedSubsystems[name]
if !supported {
return false
}
// Check if needed.
if metrics == nil || metric == "" {
return true
}
return metrics.Has(metric)
}
func diskStatsCopy0(major, minor uint64) *info.PerDiskStats {
disk := info.PerDiskStats{
Major: major,
Minor: minor,
}
disk.Stats = make(map[string]uint64)
return &disk
}
type diskKey struct {
Major uint64
Minor uint64
}
func diskStatsCopy1(diskStat map[diskKey]*info.PerDiskStats) []info.PerDiskStats {
i := 0
stat := make([]info.PerDiskStats, len(diskStat))
for _, disk := range diskStat {
stat[i] = *disk
i++
}
return stat
}
func diskStatsCopy(blkioStats []cgroups.BlkioStatEntry) (stat []info.PerDiskStats) {
if len(blkioStats) == 0 {
return
}
diskStat := make(map[diskKey]*info.PerDiskStats)
for i := range blkioStats {
major := blkioStats[i].Major
minor := blkioStats[i].Minor
key := diskKey{
Major: major,
Minor: minor,
}
diskp, ok := diskStat[key]
if !ok {
diskp = diskStatsCopy0(major, minor)
diskStat[key] = diskp
}
op := blkioStats[i].Op
if op == "" {
op = "Count"
}
diskp.Stats[op] = blkioStats[i].Value
}
return diskStatsCopy1(diskStat)
}
func NewCgroupManager(name string, paths map[string]string) (cgroups.Manager, error) {
config := &configs.Cgroup{
Name: name,
Resources: &configs.Resources{},
}
if cgroups.IsCgroup2UnifiedMode() {
path := paths[""]
return fs2.NewManager(config, path)
}
return fs.NewManager(config, paths)
}