Patent · US Expired

Method and logical apparatus for switching between single-threaded and multi-threaded execution states in a simultaneous multi-threaded (SMT) processor

US7155600B2 · kind B2 · utility

70Cited by
3References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 24, 2003
Grant dateDec 26, 2006
Priority date
Expiry dateSep 17, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/485
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method and logical apparatus for switching between single-threaded and multi-threaded execution states within a simultaneous multi-threaded (SMT) processor provides a mechanism for switching between single-threaded and multi-threaded execution. The processor receives an instruction specifying a transition from a single-threaded to a multi-threaded mode or vice-versa and halts execution of all threads executing on the processor. Internal control logic controls a sequence of events that ends instruction prefetching, dispatch of new instructions, interrupt processing and maintenance operations and waits for operation of the processor to complete for instructions that are in process. Then, the logic determines one or more threads to start in conformity with a thread enable state specifying the enable state of multiple threads and reallocates various resources, dividing them between threads if multiple threads are specified for further execution (multi-threaded mode) or allocating substantially all of the resources to a single thread if further execution is specified as single-threaded mode. The processor then starts execution of the remaining enabled threads.

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