1. A method for controlling the allocation of processing work in a system having a plurality of graphics processing units available for processing, the method comprising: receiving an affinity mask that enables an application to determine which graphics processing units in the plurality of graphics processing units are most appropriate for processing work associated with a first current rendering context; generating an affinity device context that includes the affinity mask, wherein the affinity mask is located within the affinity device context; and generating an affinity rendering context associated with the affinity device context, wherein the affinity rendering context inherits the affinity mask from the affinity device context.