}

	// if no update is needed return right away.
	if !update {
		z.poolMetaMutex.Lock()
		z.poolMeta = meta
		z.poolMetaMutex.Unlock()
	} else {
		newMeta := newPoolMeta(z, meta)
		if err = newMeta.save(ctx, z.serverPools); err != nil {
			return err
		}
		z.poolMetaMutex.Lock()
		z.poolMeta = newMeta
		z.poolMetaMutex.Unlock()
	}

	pools := meta.returnResumablePools()

		return
	}

	// Take read lock on object, here so subsequent lower-level
	// calls do not need to.
	lock := objectAPI.NewNSLock(bucket, object)
	lkctx, err := lock.GetRLock(ctx, globalOperationTimeout)
	if err != nil {
		writeErrorResponse(ctx, w, toAPIError(ctx, err), r.URL)
		return
	}
	ctx = lkctx.Context()
	defer lock.RUnlock(lkctx)

	getObjectNInfo := objectAPI.GetObjectNInfo

	timeout.LogSuccess(UTCNow().Sub(start))
	return LockContext{ctx: newCtx, cancel: cancel}, nil
}

// Unlock - block until write lock is released.
func (di *distLockInstance) Unlock(lc LockContext) {
	if lc.cancel != nil {
		lc.cancel()
	}
	di.rwMutex.Unlock(context.Background())
}

// RLock - block until read lock is taken or timeout has occurred.

	*LockedFile
	mutex sync.Mutex
	refs  int // Holds read lock refs.
}

// IsClosed - Check if the rlocked file is already closed.
func (r *RLockedFile) IsClosed() bool {
	r.mutex.Lock()
	defer r.mutex.Unlock()
	return r.refs == 0
}

// IncLockRef - is used by called to indicate lock refs.
func (r *RLockedFile) IncLockRef() {
	r.mutex.Lock()
	r.refs++
	r.mutex.Unlock()
}

	if responses == nil {
		return nil, errors.New("RequestStream: responses channel is nil")
	}
	m.init = true
	m.respMu.Lock()
	if m.closed {
		m.respMu.Unlock()
		return nil, ErrDisconnected
	}
	m.respWait = responses // Route directly to output.
	m.respMu.Unlock()

	// Try to grab an initial block.
	m.singleResp = false
	m.RecvSeq = m.SendSeq // Sync
	if cap(requests) > 0 {

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package dsync

//go:generate msgp -file $GOFILE

// LockArgs is minimal required values for any dsync compatible lock operation.
type LockArgs struct {
	// Unique ID of lock/unlock request.
	UID string

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

		err = errLockNotInitialized
	default:
		err = errors.New(r.Err)
	}
	return ok, err
}

// RLock calls read lock REST API.
func (c *lockRESTClient) RLock(ctx context.Context, args dsync.LockArgs) (reply bool, err error) {
	return c.call(ctx, lockRPCRLock, &args)
}

// Lock calls lock REST API.
func (c *lockRESTClient) Lock(ctx context.Context, args dsync.LockArgs) (reply bool, err error) {
	return c.call(ctx, lockRPCLock, &args)
}

		if !ok || mid == nil {
			resp(true)
			return
		}
		mid.respMu.Lock()
		resp(mid.closed)
		mid.respMu.Unlock()
	case debugBlockInboundMessages:
		c.connMu.Lock()
		block := (<-chan struct{})(args[0].(chan struct{}))
		c.blockMessages.Store(&block)
		c.connMu.Unlock()
	}
}

// wsWriter writes websocket messages.
type wsWriter struct {

func (r *RingBuffer) Reset() {
	r.mu.Lock()
	defer r.mu.Unlock()

	// Set error so any readers/writers will return immediately.
	r.setErr(errors.New("reset called"), true)
	if r.block {
		r.readCond.Broadcast()
		r.writeCond.Broadcast()
	}

	// Unlock the mutex so readers/writers can finish.
	r.mu.Unlock()
	r.wg.Wait()
	r.mu.Lock()
	r.r = 0
	r.w = 0
	r.err = nil

    Lock myLock = CycleDetectingLockFactory.newInstance(Policies.THROW).newReentrantLock("MyLock");
    lock03.lock();
    myLock.lock();
    lock03.unlock();

    PotentialDeadlockException expected =
        assertThrows(PotentialDeadlockException.class, () -> lock01.lock());
    checkMessage(
        expected,
        "MyLock -> OtherOrder.FIRST",
        "OtherOrder.THIRD -> MyLock",