Refresh row after Datatable event after CellEdit primefaces!

I'm updating a datatable cell, it has 3 columns, description, current price, and old price. I can normally call the bean to make the change and save in the bd. But I can not update the record in the datatable. I can not update the "row" of the cell I'm sending. I tried through, tried through the RequestContext, but I did not succeed in both.

    <p:dataTable var="tabela" 
value="#{cad012Bean.listaCptTerceirizadaServico}" 
editable="true" editMode="cell"
id="listadeServicosTerceirizados"
emptyMessage="Sem registro para mostrar"
widgetVar="#{widgetVar}" rowIndexVar="rowIndex">

    <p:ajax event="cellEdit" listener="#{cad012Bean.onCellEdit}" update=":listadeServicosTerceirizados" />

    <p:column headerText="Serviço" filterBy="#{tabela.descricao}" filterMatchMode="contains">
        <h:outputText value="#{tabela.descricao}"  />
    </p:column> 
    <p:column headerText="Valor atual"> 
        <p:cellEditor>
                <f:facet name="output">
                        <h:outputText value="#{tabela.valor}" id="e"/>
                    </f:facet>
                    <f:facet name="input">
                        <p:inputText value="#{tabela.valor}"/>
                    </f:facet>
            </p:cellEditor>
     </p:column> 
     <p:column headerText="Valor anterior">
        <h:outputText value="#{cad012Bean.retornaValorAnterior(rowIndex)}" />
     </p:column> 
</p:dataTable>