// Do read unlock for given LockArgs. It should return
	// * a boolean to indicate success/failure of the operation
	// * an error on failure of unlock request operation.
	// Canceling the context will abort the remote call.
	// In that case, the resource may or may not be unlocked.
	RUnlock(ctx context.Context, args LockArgs) (bool, error)

	// Do write unlock for given LockArgs. It should return

	m.init.Do(m.initManager)
	m.mu.Lock()
	b, ok := m.buckets[bucket]
	if !ok {
		m.mu.Unlock()
		return
	}
	delete(m.buckets, bucket)
	m.mu.Unlock()

	// Since deletes may take some time we try to do it without
	// holding lock to m all the time.
	b.mu.Lock()
	defer b.mu.Unlock()
	for k, v := range b.caches {
		if time.Since(v.lastUpdate) > metacacheMaxRunningAge {

			select {
			// Check after a second
			case <-time.After(time.Second):
				h.mutex.Unlock()
				continue

			case <-h.ctx.Done():
				h.mutex.Unlock()
				// discard result and return.
				return errHealStopSignalled

			// Timeout if no results consumed for too long.
			case <-unconsumedTimer.C:
				h.mutex.Unlock()
				return errHealIdleTimeout
			}
		}
		break
	}

		}()
		time.Sleep(1 * time.Millisecond) // wait for goroutine to advance; ref=2

		// Unlock the 1st lock; ref=1 after this line
		nsLk.unlock("volume", "path", false)

		// Taking another lockMapMutex here allows queuing up additional lockers. This should
		// not be required but makes reproduction much easier.
		nsLk.lockMapMutex.Lock()

		// lk3 blocks.
		lk3ch := make(chan bool)
		go func() {

// UnlockHandler - releases the acquired lock.
func (l *lockRESTServer) UnlockHandler(args *dsync.LockArgs) (*dsync.LockResp, *grid.RemoteErr) {
	resp := lockRPCUnlock.NewResponse()
	_, err := l.ll.Unlock(context.Background(), *args)
	// Ignore the Unlock() "reply" return value because if err == nil, "reply" is always true
	// Consequently, if err != nil, reply is always false
	return l.makeResp(resp, err)
}

// RLockHandler - Acquires an RLock.

			delete(n.lockMap, resource)
		}
		n.lockMapMutex.Unlock()
	}

	return locked
}

// Unlock the namespace resource.
func (n *nsLockMap) unlock(volume string, path string, readLock bool) {
	resource := pathJoin(volume, path)

	n.lockMapMutex.Lock()
	defer n.lockMapMutex.Unlock()
	if _, found := n.lockMap[resource]; !found {
		return
	}
	if readLock {

}

func (t *tierMetrics) logSuccess(tier string) {
	t.Lock()
	defer t.Unlock()

	stat := t.requestsCount[tier]
	stat.success++
	t.requestsCount[tier] = stat
}

func (t *tierMetrics) logFailure(tier string) {
	t.Lock()
	defer t.Unlock()

	stat := t.requestsCount[tier]
	stat.failure++
	t.requestsCount[tier] = stat
}

var (

	m.tlock.Unlock()
	m.mlock.Lock()
	delete(m.bucketsMeasurement, BucketOptions{Name: bucket, ReplicationARN: arn})
	m.mlock.Unlock()
}

// throttle returns currently configured throttle for this bucket
func (m *Monitor) throttle(opts BucketOptions) *bucketThrottle {
	m.tlock.RLock()
	defer m.tlock.RUnlock()
	return m.bucketsThrottle[opts]
}

type LockArgs struct {
	// Unique ID of lock/unlock request.
	UID string

	// Resources contains single or multiple entries to be locked/unlocked.
	Resources []string

	// Owner represents unique ID for this instance, an owner who originally requested
	// the locked resource, useful primarily in figuring out stale locks.
	Owner string

	sys.aMutex.Lock()
	defer sys.aMutex.Unlock()
	if v, ok := sys.arnErrsMap[arn]; !ok {
		sys.arnErrsMap[arn] = arnErrs{
			updateInProgress: true,
			count:            v.count + 1,
			bucket:           bucket,
		}
	}
}

func (sys *BucketTargetSys) markRefreshDone(bucket, arn string) {
	sys.aMutex.Lock()
	defer sys.aMutex.Unlock()
	if v, ok := sys.arnErrsMap[arn]; ok {