Move scheduler code out of plugin directory.

This moves plugin/pkg/scheduler to pkg/scheduler and
plugin/cmd/kube-scheduler to cmd/kube-scheduler.

Bulk of the work was done with gomvpkg, except for kube-scheduler main
package.

pkg/scheduler/algorithm/predicates/utils.go

@@ -0,0 +1,202 @@
+/*
+Copyright 2016 The Kubernetes 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 predicates
+
+import (
+	"strings"
+
+	"github.com/golang/glog"
+
+	"k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/labels"
+	"k8s.io/apimachinery/pkg/util/sets"
+	"k8s.io/kubernetes/pkg/scheduler/algorithm"
+	schedutil "k8s.io/kubernetes/pkg/scheduler/util"
+)
+
+// FindLabelsInSet gets as many key/value pairs as possible out of a label set.
+func FindLabelsInSet(labelsToKeep []string, selector labels.Set) map[string]string {
+	aL := make(map[string]string)
+	for _, l := range labelsToKeep {
+		if selector.Has(l) {
+			aL[l] = selector.Get(l)
+		}
+	}
+	return aL
+}
+
+// AddUnsetLabelsToMap backfills missing values with values we find in a map.
+func AddUnsetLabelsToMap(aL map[string]string, labelsToAdd []string, labelSet labels.Set) {
+	for _, l := range labelsToAdd {
+		// if the label is already there, dont overwrite it.
+		if _, exists := aL[l]; exists {
+			continue
+		}
+		// otherwise, backfill this label.
+		if labelSet.Has(l) {
+			aL[l] = labelSet.Get(l)
+		}
+	}
+}
+
+// FilterPodsByNamespace filters pods outside a namespace from the given list.
+func FilterPodsByNamespace(pods []*v1.Pod, ns string) []*v1.Pod {
+	filtered := []*v1.Pod{}
+	for _, nsPod := range pods {
+		if nsPod.Namespace == ns {
+			filtered = append(filtered, nsPod)
+		}
+	}
+	return filtered
+}
+
+// CreateSelectorFromLabels is used to define a selector that corresponds to the keys in a map.
+func CreateSelectorFromLabels(aL map[string]string) labels.Selector {
+	if aL == nil || len(aL) == 0 {
+		return labels.Everything()
+	}
+	return labels.Set(aL).AsSelector()
+}
+
+// EquivalencePodGenerator is a generator of equivalence class for pod with consideration of PVC info.
+type EquivalencePodGenerator struct {
+	pvcInfo PersistentVolumeClaimInfo
+}
+
+// NewEquivalencePodGenerator returns a getEquivalencePod method with consideration of PVC info.
+func NewEquivalencePodGenerator(pvcInfo PersistentVolumeClaimInfo) algorithm.GetEquivalencePodFunc {
+	g := &EquivalencePodGenerator{
+		pvcInfo: pvcInfo,
+	}
+	return g.getEquivalencePod
+}
+
+// GetEquivalencePod returns a EquivalencePod which contains a group of pod attributes which can be reused.
+func (e *EquivalencePodGenerator) getEquivalencePod(pod *v1.Pod) interface{} {
+	// For now we only consider pods:
+	// 1. OwnerReferences is Controller
+	// 2. with same OwnerReferences
+	// 3. with same PVC claim
+	// to be equivalent
+	for _, ref := range pod.OwnerReferences {
+		if ref.Controller != nil && *ref.Controller {
+			if pvcSet, err := e.getPVCSet(pod); err == nil {
+				// A pod can only belongs to one controller, so let's return.
+				return &EquivalencePod{
+					ControllerRef: ref,
+					PVCSet:        pvcSet,
+				}
+			} else {
+				// If error encountered, log warning and return nil (i.e. no equivalent pod found)
+				glog.Warningf("[EquivalencePodGenerator] for pod: %v failed due to: %v", pod.GetName(), err)
+				return nil
+			}
+		}
+	}
+	return nil
+}
+
+// getPVCSet returns a set of PVC UIDs of given pod.
+func (e *EquivalencePodGenerator) getPVCSet(pod *v1.Pod) (sets.String, error) {
+	result := sets.NewString()
+	for _, volume := range pod.Spec.Volumes {
+		if volume.PersistentVolumeClaim == nil {
+			continue
+		}
+		pvcName := volume.PersistentVolumeClaim.ClaimName
+		pvc, err := e.pvcInfo.GetPersistentVolumeClaimInfo(pod.GetNamespace(), pvcName)
+		if err != nil {
+			return nil, err
+		}
+		result.Insert(string(pvc.UID))
+	}
+
+	return result, nil
+}
+
+// EquivalencePod is a group of pod attributes which can be reused as equivalence to schedule other pods.
+type EquivalencePod struct {
+	ControllerRef metav1.OwnerReference
+	PVCSet        sets.String
+}
+
+type hostPortInfo struct {
+	protocol string
+	hostIP   string
+	hostPort string
+}
+
+// decode decodes string ("protocol/hostIP/hostPort") to *hostPortInfo object.
+func decode(info string) *hostPortInfo {
+	hostPortInfoSlice := strings.Split(info, "/")
+
+	protocol := hostPortInfoSlice[0]
+	hostIP := hostPortInfoSlice[1]
+	hostPort := hostPortInfoSlice[2]
+
+	return &hostPortInfo{
+		protocol: protocol,
+		hostIP:   hostIP,
+		hostPort: hostPort,
+	}
+}
+
+// specialPortConflictCheck detects whether specailHostPort(whose hostIP is 0.0.0.0) is conflict with otherHostPorts.
+// return true if we have a conflict.
+func specialPortConflictCheck(specialHostPort string, otherHostPorts map[string]bool) bool {
+	specialHostPortInfo := decode(specialHostPort)
+
+	if specialHostPortInfo.hostIP == schedutil.DefaultBindAllHostIP {
+		// loop through all the otherHostPorts to see if there exists a conflict
+		for hostPortItem := range otherHostPorts {
+			hostPortInfo := decode(hostPortItem)
+
+			// if there exists one hostPortItem which has the same hostPort and protocol with the specialHostPort, that will cause a conflict
+			if specialHostPortInfo.hostPort == hostPortInfo.hostPort && specialHostPortInfo.protocol == hostPortInfo.protocol {
+				return true
+			}
+		}
+
+	}
+
+	return false
+}
+
+// portsConflict check whether existingPorts and wantPorts conflict with each other
+// return true if we have a conflict
+func portsConflict(existingPorts, wantPorts map[string]bool) bool {
+
+	for existingPort := range existingPorts {
+		if specialPortConflictCheck(existingPort, wantPorts) {
+			return true
+		}
+	}
+
+	for wantPort := range wantPorts {
+		if specialPortConflictCheck(wantPort, existingPorts) {
+			return true
+		}
+
+		// general check hostPort conflict procedure for hostIP is not 0.0.0.0
+		if existingPorts[wantPort] {
+			return true
+		}
+	}
+
+	return false
+}