mirror of https://github.com/k3s-io/k3s
93 lines
2.8 KiB
Go
93 lines
2.8 KiB
Go
/*
|
|
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 controller
|
|
|
|
import (
|
|
"hash/fnv"
|
|
"sync"
|
|
|
|
"github.com/golang/groupcache/lru"
|
|
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
|
|
hashutil "k8s.io/kubernetes/pkg/util/hash"
|
|
)
|
|
|
|
type objectWithMeta interface {
|
|
metav1.Object
|
|
}
|
|
|
|
// keyFunc returns the key of an object, which is used to look up in the cache for it's matching object.
|
|
// Since we match objects by namespace and Labels/Selector, so if two objects have the same namespace and labels,
|
|
// they will have the same key.
|
|
func keyFunc(obj objectWithMeta) uint64 {
|
|
hash := fnv.New32a()
|
|
hashutil.DeepHashObject(hash, &equivalenceLabelObj{
|
|
namespace: obj.GetNamespace(),
|
|
labels: obj.GetLabels(),
|
|
})
|
|
return uint64(hash.Sum32())
|
|
}
|
|
|
|
type equivalenceLabelObj struct {
|
|
namespace string
|
|
labels map[string]string
|
|
}
|
|
|
|
// MatchingCache save label and selector matching relationship
|
|
type MatchingCache struct {
|
|
mutex sync.RWMutex
|
|
cache *lru.Cache
|
|
}
|
|
|
|
// NewMatchingCache return a NewMatchingCache, which save label and selector matching relationship.
|
|
func NewMatchingCache(maxCacheEntries int) *MatchingCache {
|
|
return &MatchingCache{
|
|
cache: lru.New(maxCacheEntries),
|
|
}
|
|
}
|
|
|
|
// Add will add matching information to the cache.
|
|
func (c *MatchingCache) Add(labelObj objectWithMeta, selectorObj objectWithMeta) {
|
|
key := keyFunc(labelObj)
|
|
c.mutex.Lock()
|
|
defer c.mutex.Unlock()
|
|
c.cache.Add(key, selectorObj)
|
|
}
|
|
|
|
// GetMatchingObject lookup the matching object for a given object.
|
|
// Note: the cache information may be invalid since the controller may be deleted or updated,
|
|
// we need check in the external request to ensure the cache data is not dirty.
|
|
func (c *MatchingCache) GetMatchingObject(labelObj objectWithMeta) (controller interface{}, exists bool) {
|
|
key := keyFunc(labelObj)
|
|
// NOTE: we use Lock() instead of RLock() here because lru's Get() method also modifies state(
|
|
// it need update the least recently usage information). So we can not call it concurrently.
|
|
c.mutex.Lock()
|
|
defer c.mutex.Unlock()
|
|
return c.cache.Get(key)
|
|
}
|
|
|
|
// Update update the cached matching information.
|
|
func (c *MatchingCache) Update(labelObj objectWithMeta, selectorObj objectWithMeta) {
|
|
c.Add(labelObj, selectorObj)
|
|
}
|
|
|
|
// InvalidateAll invalidate the whole cache.
|
|
func (c *MatchingCache) InvalidateAll() {
|
|
c.mutex.Lock()
|
|
defer c.mutex.Unlock()
|
|
c.cache = lru.New(c.cache.MaxEntries)
|
|
}
|