mig_info_provider.go:fillMigInstances will now use locking when calli…

…ng the gce api.

This is to avoid multiple gce calls for the same mig during scale down (which is done in parallel).

cluster-autoscaler/cloudprovider/gce/mig_info_provider.go

@@ -49,12 +49,13 @@ type MigInfoProvider interface {
 }
 
 type cachingMigInfoProvider struct {
-	mutex                  sync.Mutex
+	migInfoMutex           sync.Mutex
 	cache                  *GceCache
 	migLister              MigLister
 	gceClient              AutoscalingGceClient
 	projectId              string
 	concurrentGceRefreshes int
+	migInstanceMutex       sync.Mutex
 }
 
 // NewCachingMigInfoProvider creates an instance of caching MigInfoProvider
@@ -85,6 +86,9 @@ func (c *cachingMigInfoProvider) GetMigInstances(migRef GceRef) ([]cloudprovider
 
 // GetMigForInstance returns MIG ref for a given instance
 func (c *cachingMigInfoProvider) GetMigForInstance(instanceRef GceRef) (Mig, error) {
+	c.migInstanceMutex.Lock()
+	defer c.migInstanceMutex.Unlock()
+
 	mig, found, err := c.getCachedMigForInstance(instanceRef)
 	if found {
 		return mig, err
@@ -160,8 +164,8 @@ func (c *cachingMigInfoProvider) fillMigInstances(migRef GceRef) error {
 }
 
 func (c *cachingMigInfoProvider) GetMigTargetSize(migRef GceRef) (int64, error) {
-	c.mutex.Lock()
-	defer c.mutex.Unlock()
+	c.migInfoMutex.Lock()
+	defer c.migInfoMutex.Unlock()
 
 	targetSize, found := c.cache.GetMigTargetSize(migRef)
 	if found {
@@ -185,8 +189,8 @@ func (c *cachingMigInfoProvider) GetMigTargetSize(migRef GceRef) (int64, error)
 }
 
 func (c *cachingMigInfoProvider) GetMigBasename(migRef GceRef) (string, error) {
-	c.mutex.Lock()
-	defer c.mutex.Unlock()
+	c.migInfoMutex.Lock()
+	defer c.migInfoMutex.Unlock()
 
 	basename, found := c.cache.GetMigBasename(migRef)
 	if found {
@@ -210,8 +214,8 @@ func (c *cachingMigInfoProvider) GetMigBasename(migRef GceRef) (string, error) {
 }
 
 func (c *cachingMigInfoProvider) GetMigInstanceTemplateName(migRef GceRef) (string, error) {
-	c.mutex.Lock()
-	defer c.mutex.Unlock()
+	c.migInfoMutex.Lock()
+	defer c.migInfoMutex.Unlock()
 
 	templateName, found := c.cache.GetMigInstanceTemplateName(migRef)
 	if found {
@@ -240,8 +244,8 @@ func (c *cachingMigInfoProvider) GetMigInstanceTemplate(migRef GceRef) (*gce.Ins
 		return nil, err
 	}
 
-	c.mutex.Lock()
-	defer c.mutex.Unlock()
+	c.migInfoMutex.Lock()
+	defer c.migInfoMutex.Unlock()
 
 	template, found := c.cache.GetMigInstanceTemplate(migRef)
 	if found && template.Name == templateName {
@@ -257,7 +261,7 @@ func (c *cachingMigInfoProvider) GetMigInstanceTemplate(migRef GceRef) (*gce.Ins
 	return template, nil
 }
 
-// filMigInfoCache needs to be called with mutex locked
+// filMigInfoCache needs to be called with migInfoMutex locked
 func (c *cachingMigInfoProvider) fillMigInfoCache() error {
 	var zones []string
 	for zone := range c.listAllZonesWithMigs() {