// Check if minimally a single bool is set in the writeLocks array
		lockFound := false
		for _, uid := range dm.writeLocks {
			if isLocked(uid) {
				lockFound = true
				break
			}
		}
		if !lockFound {
			panic("Trying to Unlock() while no Lock() is active")
		}

		// Copy write locks to stack array
		copy(locks, dm.writeLocks)
	}

    // Establish an ordering from writeLockA -> writeLockB.
    writeLockA.lock();
    writeLockB.lock();
    writeLockB.unlock();
    writeLockA.unlock();

    // Establish an ordering from writeLockB -> writeLockC.
    writeLockB.lock();
    writeLockC.lock();
    writeLockB.unlock();

    // writeLockC -> writeLockA should fail.
    PotentialDeadlockException expected =

    // Establish an ordering from writeLockA -> writeLockB.
    writeLockA.lock();
    writeLockB.lock();
    writeLockB.unlock();
    writeLockA.unlock();

    // Establish an ordering from writeLockB -> writeLockC.
    writeLockB.lock();
    writeLockC.lock();
    writeLockB.unlock();

    // writeLockC -> writeLockA should fail.
    PotentialDeadlockException expected =

				ReadIOs:        1432553,
				ReadMerges:     420084,
				ReadSectors:    66247626,
				ReadTicks:      2398227,
				WriteIOs:       7077314,
				WriteMerges:    8720147,
				WriteSectors:   157049224,
				WriteTicks:     7469810,
				CurrentIOs:     0,
				TotalTicks:     7580552,
				ReqTicks:       9869354,
				DiscardIOs:     46037,
				DiscardMerges:  0,
				DiscardSectors: 41695120,
				DiscardTicks:   1315,

		subrouter.Methods(http.MethodPost).Path("/v1/force-unlock").HandlerFunc(lockServer.ForceUnlockHandler)

		nodes[i] = httptest.NewServer(router)
	}
}

const WriteLock = -1

type lockServer struct {
	mutex sync.Mutex
	// Map of locks, with negative value indicating (exclusive) write lock
	// and positive values indicating number of read locks
	lockMap map[string]int64

		WriteSectors: currentStats.WriteSectors - initialStats.WriteSectors,
		ReadTicks:    currentStats.ReadTicks - initialStats.ReadTicks,
		WriteTicks:   currentStats.WriteTicks - initialStats.WriteTicks,
		TotalTicks:   currentStats.TotalTicks - initialStats.TotalTicks,
	}
}

func getDriveIOStatMetrics(ioStats madmin.DiskIOStats, duration time.Duration) (m driveIOStatMetrics) {

    Lock readLock = striped.get(key).readLock();
    WeakReference<Object> garbage = new WeakReference<>(new Object());
    GcFinalization.awaitClear(garbage);
    Lock writeLock = striped.get(key).writeLock();
    readLock.lock();
    assertFalse(writeLock.tryLock());
    readLock.unlock();
  }

  @AndroidIncompatible // Presumably GC doesn't trigger, despite our efforts.
  public void testStrongImplementations() {

    Lock readLock = striped.get(key).readLock();
    WeakReference<Object> garbage = new WeakReference<>(new Object());
    GcFinalization.awaitClear(garbage);
    Lock writeLock = striped.get(key).writeLock();
    readLock.lock();
    assertFalse(writeLock.tryLock());
    readLock.unlock();
  }

  @AndroidIncompatible // Presumably GC doesn't trigger, despite our efforts.
  public void testStrongImplementations() {

      this.writeLock = new CycleDetectingReentrantWriteLock(this);
      this.lockGraphNode = Preconditions.checkNotNull(lockGraphNode);
    }

    ///// Overridden ReentrantReadWriteLock methods. /////

    @Override
    public ReadLock readLock() {
      return readLock;
    }

    @Override
    public WriteLock writeLock() {
      return writeLock;
    }

				ReadSectors:    st.ReadSectors,
				ReadTicks:      st.ReadTicks,
				WriteIOs:       st.WriteIOs,
				WriteMerges:    st.WriteMerges,
				WriteSectors:   st.WriteSectors,
				WriteTicks:     st.WriteTicks,
				CurrentIOs:     st.CurrentIOs,
				TotalTicks:     st.TotalTicks,
				ReqTicks:       st.ReqTicks,
				DiscardIOs:     st.DiscardIOs,
				DiscardMerges:  st.DiscardMerges,