SLEEP STATE MECHANISM FOR VIRTUAL MULTITHREADING

摘要

Method, apparatus and system embodiments provide support for multiple SoEMT software threads on multiple SMT logical thread contexts. A sleep state mechanism maintains a current value of an element of architecture state for each physical thread. The current value corresponds to an active virtual thread currently running on the physical thread. The sleep state mechanism also maintains sleep values of the architecture state element for each inactive thread. The active and inactive values may be maintained in a cross-bar configuration. Upon a read of the architecture state element, simplified mux logic selects among the current values to provide the current value for the appropriate active thread. Upon a thread switch, control logic associated with the sleep state mechanism swaps the active state value for the current thread with the inactive state value for the new thread.