Patent · US Active

Context switching system having context cache and a register file for the save and restore context operation

US8020169B2 · kind B2 · utility

59Cited by
9References
13Claims
0Family size

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Inventor

Key dates

Filing dateDec 11, 2003
Grant dateSep 13, 2011
Priority date
Expiry dateSep 2, 2027

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/461
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

In an application in which context switching often occurs such as in a real time OS, it is possible to significantly reduce the overhead caused by the context switching. The OS issues a Swap instruction and a context switch starts. The Swap instruction is issued together with a thread (i.e., context) ID to be replaced, to a thread control unit (9). The thread ID is used to uniquely identify threads stored in a context cache (8). The thread control unit (9) saves data from a register file (1) to the context cache (8) via a context-dedicated bus (12) and transmits data of a new thread from the context cache (8) to the register file (1). According to the thread ID received, the thread control unit (9) automatically interchanges the necessary number of data in the register file (1) and the data in the context cache (8).

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