Merge pull request #108007 from endocrimes/dani/cm-remove-docker

cm: Remove legacy docker references

pkg/kubelet/cm/container_manager_linux.go

@@ -25,7 +25,6 @@ import (
 	"io/ioutil"
 	"os"
 	"path"
-	"strconv"
 	"strings"
 	"sync"
 	"time"
@@ -36,7 +35,6 @@ import (
 	"github.com/opencontainers/runc/libcontainer/configs"
 	"k8s.io/klog/v2"
 	"k8s.io/mount-utils"
-	utilio "k8s.io/utils/io"
 	utilpath "k8s.io/utils/path"
 
 	libcontaineruserns "github.com/opencontainers/runc/libcontainer/userns"
@@ -44,7 +42,6 @@ import (
 	"k8s.io/apimachinery/pkg/api/resource"
 	utilerrors "k8s.io/apimachinery/pkg/util/errors"
 	"k8s.io/apimachinery/pkg/util/sets"
-	utilversion "k8s.io/apimachinery/pkg/util/version"
 	"k8s.io/apimachinery/pkg/util/wait"
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/client-go/tools/record"
@@ -70,20 +67,6 @@ import (
 	"k8s.io/kubernetes/pkg/kubelet/status"
 	schedulerframework "k8s.io/kubernetes/pkg/scheduler/framework"
 	"k8s.io/kubernetes/pkg/util/oom"
-	"k8s.io/kubernetes/pkg/util/procfs"
-)
-
-const (
-	dockerProcessName = "dockerd"
-	// dockerd option --pidfile can specify path to use for daemon PID file, pid file path is default "/var/run/docker.pid"
-	dockerPidFile         = "/var/run/docker.pid"
-	containerdProcessName = "containerd"
-	maxPidFileLength      = 1 << 10 // 1KB
-)
-
-var (
-	// The docker version in which containerd was introduced.
-	containerdAPIVersion = utilversion.MustParseGeneric("1.23")
 )
 
 // A non-user container tracked by the Kubelet.
@@ -496,24 +479,6 @@ func (cm *containerManagerImpl) setupNode(activePods ActivePodsFunc) error {
 	}
 
 	systemContainers := []*systemContainer{}
-	if cm.ContainerRuntime == "docker" {
-		// With the docker-CRI integration, dockershim manages the cgroups
-		// and oom score for the docker processes.
-		// Check the cgroup for docker periodically, so kubelet can serve stats for the docker runtime.
-		// TODO(KEP#866): remove special processing for CRI "docker" enablement
-		cm.periodicTasks = append(cm.periodicTasks, func() {
-			klog.V(4).InfoS("Adding periodic tasks for docker CRI integration")
-			cont, err := getContainerNameForProcess(dockerProcessName, dockerPidFile)
-			if err != nil {
-				klog.ErrorS(err, "Failed to get container name for process")
-				return
-			}
-			klog.V(2).InfoS("Discovered runtime cgroup name", "cgroupName", cont)
-			cm.Lock()
-			defer cm.Unlock()
-			cm.RuntimeCgroupsName = cont
-		})
-	}
 
 	if cm.SystemCgroupsName != "" {
 		if cm.SystemCgroupsName == "/" {
@@ -561,21 +526,6 @@ func (cm *containerManagerImpl) setupNode(activePods ActivePodsFunc) error {
 	return nil
 }
 
-func getContainerNameForProcess(name, pidFile string) (string, error) {
-	pids, err := getPidsForProcess(name, pidFile)
-	if err != nil {
-		return "", fmt.Errorf("failed to detect process id for %q - %v", name, err)
-	}
-	if len(pids) == 0 {
-		return "", nil
-	}
-	cont, err := getContainer(pids[0])
-	if err != nil {
-		return "", err
-	}
-	return cont, nil
-}
-
 func (cm *containerManagerImpl) GetNodeConfig() NodeConfig {
 	cm.RLock()
 	defer cm.RUnlock()
@@ -820,78 +770,6 @@ func isProcessRunningInHost(pid int) (bool, error) {
 	return initPidNs == processPidNs, nil
 }
 
-func getPidFromPidFile(pidFile string) (int, error) {
-	file, err := os.Open(pidFile)
-	if err != nil {
-		return 0, fmt.Errorf("error opening pid file %s: %v", pidFile, err)
-	}
-	defer file.Close()
-
-	data, err := utilio.ReadAtMost(file, maxPidFileLength)
-	if err != nil {
-		return 0, fmt.Errorf("error reading pid file %s: %v", pidFile, err)
-	}
-
-	pid, err := strconv.Atoi(string(data))
-	if err != nil {
-		return 0, fmt.Errorf("error parsing %s as a number: %v", string(data), err)
-	}
-
-	return pid, nil
-}
-
-func getPidsForProcess(name, pidFile string) ([]int, error) {
-	if len(pidFile) == 0 {
-		return procfs.PidOf(name)
-	}
-
-	pid, err := getPidFromPidFile(pidFile)
-	if err == nil {
-		return []int{pid}, nil
-	}
-
-	// Try to lookup pid by process name
-	pids, err2 := procfs.PidOf(name)
-	if err2 == nil {
-		return pids, nil
-	}
-
-	// Return error from getPidFromPidFile since that should have worked
-	// and is the real source of the problem.
-	klog.V(4).InfoS("Unable to get pid from file", "path", pidFile, "err", err)
-	return []int{}, err
-}
-
-// Ensures that the Docker daemon is in the desired container.
-// Temporarily export the function to be used by dockershim.
-// TODO(yujuhong): Move this function to dockershim once kubelet migrates to
-// dockershim as the default.
-func EnsureDockerInContainer(dockerAPIVersion *utilversion.Version, oomScoreAdj int, manager cgroups.Manager) error {
-	type process struct{ name, file string }
-	dockerProcs := []process{{dockerProcessName, dockerPidFile}}
-	if dockerAPIVersion.AtLeast(containerdAPIVersion) {
-		// By default containerd is started separately, so there is no pid file.
-		containerdPidFile := ""
-		dockerProcs = append(dockerProcs, process{containerdProcessName, containerdPidFile})
-	}
-	var errs []error
-	for _, proc := range dockerProcs {
-		pids, err := getPidsForProcess(proc.name, proc.file)
-		if err != nil {
-			errs = append(errs, fmt.Errorf("failed to get pids for %q: %v", proc.name, err))
-			continue
-		}
-
-		// Move if the pid is not already in the desired container.
-		for _, pid := range pids {
-			if err := ensureProcessInContainerWithOOMScore(pid, oomScoreAdj, manager); err != nil {
-				errs = append(errs, fmt.Errorf("errors moving %q pid: %v", proc.name, err))
-			}
-		}
-	}
-	return utilerrors.NewAggregate(errs)
-}
-
 func ensureProcessInContainerWithOOMScore(pid int, oomScoreAdj int, manager cgroups.Manager) error {
 	if runningInHost, err := isProcessRunningInHost(pid); err != nil {
 		// Err on the side of caution. Avoid moving the docker daemon unless we are able to identify its context.

pkg/kubelet/cm/helpers_linux.go

@@ -25,7 +25,7 @@ import (
 
 	libcontainercgroups "github.com/opencontainers/runc/libcontainer/cgroups"
 
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/types"
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/kubernetes/pkg/api/v1/resource"
@@ -340,12 +340,5 @@ func GetKubeletContainer(kubeletCgroups string) (string, error) {
 
 // GetRuntimeContainer returns the cgroup used by the container runtime
 func GetRuntimeContainer(containerRuntime, runtimeCgroups string) (string, error) {
-	if containerRuntime == "docker" {
-		cont, err := getContainerNameForProcess(dockerProcessName, dockerPidFile)
-		if err != nil {
-			return "", fmt.Errorf("failed to get container name for docker process: %v", err)
-		}
-		return cont, nil
-	}
 	return runtimeCgroups, nil
 }