Translation lookaside buffer entry systems and methods

摘要

Presented systems and methods can facilitate efficient information storage and tracking operations, including translation look aside buffer operations. In one embodiment, the systems and methods effectively allow the caching of invalid entries (with the attendant benefits e.g., regarding power, resource usage, stalls, etc), while maintaining the illusion that the TLBs do not in fact cache invalid entries (e.g., act in compliance with architectural rules). In one exemplary implementation, an “unreal” TLB entry effectively serves as a hint that the linear address in question currently has no valid mapping. In one exemplary implementation, speculative operations that hit an unreal entry are discarded; architectural operations that hit an unreal entry discard the entry and perform a normal page walk, either obtaining a valid entry, or raising an architectural fault.

主权项

1. A method comprising:
determining a category for a memory operation, wherein the category includes at least one of an architectural category memory operation and a speculative category memory operation; and performing a TLB cache process, including handling speculative memory operation invalid page walk responses with unreal entry indicators, wherein the TLB cache process includes:
performing a page fault process if the category is determined to be an architectural category memory operation; andperforming an unreal TLB entry process if the category is determined to be a speculative category memory operation.