cri-o/oci/memory_store.go
Antonio Murdaca f67662e684
lib,oci: drop stateLock when possible
Should fix a possible deadlock in, at least, ListPodSandbox.
There seems to be no reason to hold stateLock when doing operations on
the memory_store for containers and sandboxes.

Signed-off-by: Antonio Murdaca <runcom@redhat.com>
2017-12-18 17:44:31 +01:00

93 lines
2 KiB
Go

package oci
import "sync"
// memoryStore implements a Store in memory.
type memoryStore struct {
s map[string]*Container
sync.RWMutex
}
// NewMemoryStore initializes a new memory store.
func NewMemoryStore() ContainerStorer {
return &memoryStore{
s: make(map[string]*Container),
}
}
// Add appends a new container to the memory store.
// It overrides the id if it existed before.
func (c *memoryStore) Add(id string, cont *Container) {
c.Lock()
c.s[id] = cont
c.Unlock()
}
// Get returns a container from the store by id.
func (c *memoryStore) Get(id string) *Container {
var res *Container
c.RLock()
res = c.s[id]
c.RUnlock()
return res
}
// Delete removes a container from the store by id.
func (c *memoryStore) Delete(id string) {
c.Lock()
delete(c.s, id)
c.Unlock()
}
// List returns a sorted list of containers from the store.
// The containers are ordered by creation date.
func (c *memoryStore) List() []*Container {
containers := History(c.all())
containers.sort()
return containers
}
// Size returns the number of containers in the store.
func (c *memoryStore) Size() int {
c.RLock()
defer c.RUnlock()
return len(c.s)
}
// First returns the first container found in the store by a given filter.
func (c *memoryStore) First(filter StoreFilter) *Container {
for _, cont := range c.all() {
if filter(cont) {
return cont
}
}
return nil
}
// ApplyAll calls the reducer function with every container in the store.
// This operation is asynchronous in the memory store.
// NOTE: Modifications to the store MUST NOT be done by the StoreReducer.
func (c *memoryStore) ApplyAll(apply StoreReducer) {
wg := new(sync.WaitGroup)
for _, cont := range c.all() {
wg.Add(1)
go func(container *Container) {
apply(container)
wg.Done()
}(cont)
}
wg.Wait()
}
func (c *memoryStore) all() []*Container {
c.RLock()
containers := make([]*Container, 0, len(c.s))
for _, cont := range c.s {
containers = append(containers, cont)
}
c.RUnlock()
return containers
}
var _ ContainerStorer = &memoryStore{}