1. A computer program product for implementing cache coherency verification using ordered lists, the computer program product comprising: a computer readable storage medium having program instructions embodied therewith, the program instructions readable by a processing circuit to cause the processing circuit to perform a method comprising: maintaining, by a cache coherency verification module, a plurality of ordered lists, each ordered list corresponding to a respective thread that is executed by a processor, wherein each ordered list comprises a plurality of atoms, each atom corresponding to a respective operation performed in a cache by the respective thread that corresponds to the ordered list in which the atom is located, wherein the plurality of atoms in an ordered list are ordered based on program order; determining a state of an atom in an ordered list of the plurality of ordered lists; comparing the state of the atom in an ordered list to a state of an operation corresponding to the atom in the cache; and based on the comparing, determining that there is a coherency violation in the cache.