for i := 0; i < numIterations; i++ {
		if rwm.GetRLock(context.Background(), "", "", time.Second) {
			n := atomic.AddInt32(activity, 1)
			if n < 1 || n >= 10000 {
				panic(fmt.Sprintf("wlock(%d)\n", n))
			}
			for i := 0; i < 100; i++ {
			}
			atomic.AddInt32(activity, -1)
			rwm.RUnlock()
		}
	}
	cdone <- true
}

// Borrowed from rwmutex_test.go