A method and apparatus for deterministic removal and reclamation of work
items from an expansion bus schedule are disclosed herein. A work item is
removed from an enabled expansion bus schedule data structure and a
coherency signal is then generated utilizing an expansion bus host
controller. The work item is then reclaimed in response to the generation
of the coherency signal. In one embodiment, the enabled expansion bus
schedule data structure is a Universal Serial Bus (USB) asynchronous
schedule including a plurality of queue heads.