ASP.NET - Consulta Linq

SELECT p.rut from ProvEventServs pes join Proveedors p on pes.prov=p.rut group by p.rut having count(*)>=all(select count(*)

 from ProvEventServs pes join Proveedors p on pes.prov=p.rut group by p.rut)

var ret = from pro in db.P

        join pes in db.servicioProveedorEvento on pro.rut equals pes.prov

        group by pro.rut

db = clase de contexto;

P = Proveedor

servicioProveedorEvento = ProvEventServs