Patent · US Expired

Handling cache misses by selectively flushing the pipeline

US7509484B1 · kind B1 · utility

73Cited by
62References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 30, 2004
Grant dateMar 24, 2009
Priority date
Expiry dateSep 3, 2025

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/3867
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

An apparatus and method for efficiently managing data cache load misses is described in connection with a multithreaded, pipelined multiprocessor chip. A CMT processor keeps track of load misses for each thread by issuing a load miss signal each time a load instruction to the data cache misses. A detection logic functionality in the IFU responds the load miss signal to determine if a valid instruction from the thread is at the one of the pipeline stages. If no instructions from the thread are detected in the pipeline, then no flush is required and the thread is placed in a wait state until the requested data is returned from higher order memory. If any instruction from the thread is detected in the pipeline, the thread is flushed and the instruction is re-fetched.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.