1. A computer program product for facilitating interruption processing in a computing environment, said computer program product comprising: a non-transitory computer readable storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method comprising: setting an interruption code, based on one or more requests for interruption by an adapter, the interruption code comprising an adapter interruption source mask (AISM) representing a plurality of different types of adapters, the AISM comprising a source indicator for each adapter type of the plurality of different types of adapters, an adapter interruption indicator that indicates that the one or more requests are for interruption, and an interruption subclass of the adapter requesting the interrupt, and the setting the interruption code comprising determining the adapter type of the adapter requesting an interruption, and setting a source indicator in the AISM corresponding to the determined adapter type; and presenting the interruption code to the operating system to process the one or more requests for interruption for the adapter, the adapter requesting the interruption to be determined based on the set source indicator in the interruption code, the set source indicator configured to identify an interruption mechanism of a plurality of interruption mechanisms to be examined to determine the adapter requesting the interruption.