[VOL-4211] Persist meters in the Core
Change-Id: I0f9a2914996a69be080bd8f77b3c7ae6cc902cb3
diff --git a/rw_core/core/device/meter/cache.go b/rw_core/core/device/meter/cache.go
deleted file mode 100644
index 8912bbe..0000000
--- a/rw_core/core/device/meter/cache.go
+++ /dev/null
@@ -1,148 +0,0 @@
-/*
- * Copyright 2018-present Open Networking Foundation
-
- * 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 meter
-
-import (
- "context"
- "sync"
-
- ofp "github.com/opencord/voltha-protos/v4/go/openflow_13"
-)
-
-// Cache hides all low-level locking & synchronization related to meter state updates
-type Cache struct {
- // this lock protects the meters map, it does not protect individual meters
- lock sync.RWMutex
- meters map[uint32]*chunk
-}
-
-// chunk keeps a meter and the lock for this meter
-type chunk struct {
- // this lock is used to synchronize all access to the meter, and also to the "deleted" variable
- lock sync.Mutex
- deleted bool
-
- meter *ofp.OfpMeterEntry
-}
-
-func NewCache() *Cache {
- return &Cache{
- meters: make(map[uint32]*chunk),
- }
-}
-
-// LockOrCreate locks this meter if it exists, or creates a new meter if it does not.
-// In the case of meter creation, the provided "meter" must not be modified afterwards.
-func (cache *Cache) LockOrCreate(ctx context.Context, meter *ofp.OfpMeterEntry) (*Handle, bool, error) {
- // try to use read lock instead of full lock if possible
- if handle, have := cache.Lock(meter.Config.MeterId); have {
- return handle, false, nil
- }
-
- cache.lock.Lock()
- entry, have := cache.meters[meter.Config.MeterId]
- if !have {
- entry := &chunk{meter: meter}
- cache.meters[meter.Config.MeterId] = entry
- entry.lock.Lock()
- cache.lock.Unlock()
-
- return &Handle{loader: cache, chunk: entry}, true, nil
- }
- cache.lock.Unlock()
-
- entry.lock.Lock()
- if entry.deleted {
- entry.lock.Unlock()
- return cache.LockOrCreate(ctx, meter)
- }
- return &Handle{loader: cache, chunk: entry}, false, nil
-}
-
-// Lock acquires the lock for this meter, and returns a handle which can be used to access the meter until it's unlocked.
-// This handle ensures that the meter cannot be accessed if the lock is not held.
-// Returns false if the meter is not present.
-// TODO: consider accepting a ctx and aborting the lock attempt on cancellation
-func (cache *Cache) Lock(id uint32) (*Handle, bool) {
- cache.lock.RLock()
- entry, have := cache.meters[id]
- cache.lock.RUnlock()
-
- if !have {
- return nil, false
- }
-
- entry.lock.Lock()
- if entry.deleted {
- entry.lock.Unlock()
- return cache.Lock(id)
- }
- return &Handle{loader: cache, chunk: entry}, true
-}
-
-// Handle is allocated for each Lock() call, all modifications are made using it, and it is invalidated by Unlock()
-// This enforces correct Lock()-Usage()-Unlock() ordering.
-type Handle struct {
- loader *Cache
- chunk *chunk
-}
-
-// GetReadOnly returns an *ofp.OfpMeterEntry which MUST NOT be modified externally, but which is safe to keep indefinitely
-func (h *Handle) GetReadOnly() *ofp.OfpMeterEntry {
- return h.chunk.meter
-}
-
-// Update updates an existing meter in cache.
-// The provided "meter" must not be modified afterwards.
-func (h *Handle) Update(ctx context.Context, meter *ofp.OfpMeterEntry) error {
- h.chunk.meter = meter
- return nil
-}
-
-// Delete removes the meter from the cache
-func (h *Handle) Delete(ctx context.Context) error {
- h.chunk.deleted = true
-
- h.loader.lock.Lock()
- delete(h.loader.meters, h.chunk.meter.Config.MeterId)
- h.loader.lock.Unlock()
-
- h.Unlock()
- return nil
-}
-
-// Unlock releases the lock on the meter
-func (h *Handle) Unlock() {
- if h.chunk != nil {
- h.chunk.lock.Unlock()
- h.chunk = nil // attempting to access the meter through this handle in future will panic
- }
-}
-
-// ListIDs returns a snapshot of all the managed meter IDs
-// TODO: iterating through meters safely is expensive now, since all meters are stored & locked separately
-// should avoid this where possible
-func (cache *Cache) ListIDs() map[uint32]struct{} {
- cache.lock.RLock()
- defer cache.lock.RUnlock()
- // copy the IDs so caller can safely iterate
- ret := make(map[uint32]struct{}, len(cache.meters))
- for id := range cache.meters {
- ret[id] = struct{}{}
- }
- return ret
-}
diff --git a/rw_core/core/device/meter/common.go b/rw_core/core/device/meter/common.go
new file mode 100644
index 0000000..773c0b7
--- /dev/null
+++ b/rw_core/core/device/meter/common.go
@@ -0,0 +1,33 @@
+/*
+ * Copyright 2020-present Open Networking Foundation
+ *
+ * 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 core Common Logger initialization
+package meter
+
+import (
+ "github.com/opencord/voltha-lib-go/v5/pkg/log"
+)
+
+var logger log.CLogger
+
+func init() {
+ // Setup this package so that it's log level can be modified at run time
+ var err error
+ logger, err = log.RegisterPackage(log.JSON, log.ErrorLevel, log.Fields{})
+ if err != nil {
+ panic(err)
+ }
+}
diff --git a/rw_core/core/device/meter/loader.go b/rw_core/core/device/meter/loader.go
new file mode 100644
index 0000000..42f4264
--- /dev/null
+++ b/rw_core/core/device/meter/loader.go
@@ -0,0 +1,172 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+ * 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 meter
+
+import (
+ "context"
+ "fmt"
+ "github.com/opencord/voltha-go/db/model"
+ "github.com/opencord/voltha-lib-go/v5/pkg/log"
+ ofp "github.com/opencord/voltha-protos/v4/go/openflow_13"
+ "google.golang.org/grpc/codes"
+ "google.golang.org/grpc/status"
+ "sync"
+)
+
+// Loader hides all low-level locking & synchronization related to meter state updates
+type Loader struct {
+ dbProxy *model.Proxy
+ // this lock protects the meters map, it does not protect individual meters
+ lock sync.RWMutex
+ meters map[uint32]*chunk
+}
+
+// chunk keeps a meter and the lock for this meter
+type chunk struct {
+ // this lock is used to synchronize all access to the meter, and also to the "deleted" variable
+ lock sync.Mutex
+ deleted bool
+ meter *ofp.OfpMeterEntry
+}
+
+func NewLoader(dbProxy *model.Proxy) *Loader {
+ return &Loader{
+ dbProxy: dbProxy,
+ meters: make(map[uint32]*chunk),
+ }
+}
+
+// Load queries existing meters from the kv,
+// and should only be called once when first created.
+func (loader *Loader) Load(ctx context.Context) {
+ loader.lock.Lock()
+ defer loader.lock.Unlock()
+ var meters []*ofp.OfpMeterEntry
+ if err := loader.dbProxy.List(ctx, &meters); err != nil {
+ logger.Errorw(ctx, "failed-to-list-meters-from-cluster-data-proxy", log.Fields{"error": err})
+ return
+ }
+ for _, meter := range meters {
+ loader.meters[meter.Config.MeterId] = &chunk{meter: meter}
+ }
+}
+
+// LockOrCreate locks this meter if it exists, or creates a new meter if it does not.
+// In the case of meter creation, the provided "meter" must not be modified afterwards.
+func (loader *Loader) LockOrCreate(ctx context.Context, meter *ofp.OfpMeterEntry) (*Handle, bool, error) {
+ // try to use read lock instead of full lock if possible
+ if handle, have := loader.Lock(meter.Config.MeterId); have {
+ return handle, false, nil
+ }
+ loader.lock.Lock()
+ entry, have := loader.meters[meter.Config.MeterId]
+ if !have {
+ entry := &chunk{meter: meter}
+ loader.meters[meter.Config.MeterId] = entry
+ entry.lock.Lock()
+ loader.lock.Unlock()
+ if err := loader.dbProxy.Set(ctx, fmt.Sprint(meter.Config.MeterId), meter); err != nil {
+ // revert the map
+ loader.lock.Lock()
+ delete(loader.meters, meter.Config.MeterId)
+ loader.lock.Unlock()
+ entry.deleted = true
+ entry.lock.Unlock()
+ return nil, false, err
+ }
+ return &Handle{loader: loader, chunk: entry}, true, nil
+ }
+ loader.lock.Unlock()
+ entry.lock.Lock()
+ if entry.deleted {
+ entry.lock.Unlock()
+ return loader.LockOrCreate(ctx, meter)
+ }
+ return &Handle{loader: loader, chunk: entry}, false, nil
+}
+
+// Lock acquires the lock for this meter, and returns a handle which can be used to access the meter until it's unlocked.
+// This handle ensures that the meter cannot be accessed if the lock is not held.
+// Returns false if the meter is not present.
+// TODO: consider accepting a ctx and aborting the lock attempt on cancellation
+func (loader *Loader) Lock(id uint32) (*Handle, bool) {
+ loader.lock.RLock()
+ entry, have := loader.meters[id]
+ loader.lock.RUnlock()
+ if !have {
+ return nil, false
+ }
+ entry.lock.Lock()
+ if entry.deleted {
+ entry.lock.Unlock()
+ return loader.Lock(id)
+ }
+ return &Handle{loader: loader, chunk: entry}, true
+}
+
+// Handle is allocated for each Lock() call, all modifications are made using it, and it is invalidated by Unlock()
+// This enforces correct Lock()-Usage()-Unlock() ordering.
+type Handle struct {
+ loader *Loader
+ chunk *chunk
+}
+
+// GetReadOnly returns an *ofp.OfpMeterEntry which MUST NOT be modified externally, but which is safe to keep indefinitely
+func (h *Handle) GetReadOnly() *ofp.OfpMeterEntry {
+ return h.chunk.meter
+}
+
+// Update updates an existing meter in the kv.
+// The provided "meter" must not be modified afterwards.
+func (h *Handle) Update(ctx context.Context, meter *ofp.OfpMeterEntry) error {
+ if err := h.loader.dbProxy.Set(ctx, fmt.Sprint(meter.Config.MeterId), meter); err != nil {
+ return status.Errorf(codes.Internal, "failed-update-meter-%v: %s", meter.Config.MeterId, err)
+ }
+ h.chunk.meter = meter
+ return nil
+}
+
+// Delete removes the device from the kv
+func (h *Handle) Delete(ctx context.Context) error {
+ if err := h.loader.dbProxy.Remove(ctx, fmt.Sprint(h.chunk.meter.Config.MeterId)); err != nil {
+ return fmt.Errorf("couldnt-delete-meter-from-store-%v", h.chunk.meter.Config.MeterId)
+ }
+ h.chunk.deleted = true
+ h.loader.lock.Lock()
+ delete(h.loader.meters, h.chunk.meter.Config.MeterId)
+ h.loader.lock.Unlock()
+ h.Unlock()
+ return nil
+}
+
+// Unlock releases the lock on the meter
+func (h *Handle) Unlock() {
+ if h.chunk != nil {
+ h.chunk.lock.Unlock()
+ h.chunk = nil // attempting to access the meter through this handle in future will panic
+ }
+}
+
+// ListIDs returns a snapshot of all the managed meter IDs
+// TODO: iterating through meters safely is expensive now, since all meters are stored & locked separately
+// should avoid this where possible
+func (loader *Loader) ListIDs() map[uint32]struct{} {
+ loader.lock.RLock()
+ defer loader.lock.RUnlock()
+ // copy the IDs so caller can safely iterate
+ ret := make(map[uint32]struct{}, len(loader.meters))
+ for id := range loader.meters {
+ ret[id] = struct{}{}
+ }
+ return ret
+}