The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 20, 2004
Filed:
Nov. 05, 2002
William N. Joy, Aspen, CO (US);
James Michael O'Connor, Mountain View, CA (US);
Marc Tremblay, Menlo Park, CA (US);
Sun Microsystems, Inc., Santa Clara, CA (US);
Abstract
A computer processor includes a number of register pairs LOCKADD/LOCKCOUNT to hold values identifying when a computer resource is locked. The LOCKCOUNT register is incremented or decremented in response to lock or unlock instructions, respectively. The lock is freed when a count associated with the LOCKCOUNT register is decremented to zero. In embodiments without LOCKOUT registers, the lock may be freed on any unlock instruction corresponding to the lock. In some embodiments, a computer object includes a header in which two header LSBs store: (1) a LOCK bit indicating whether the object is locked, and (2) a WANT bit indicating whether a thread is waiting to acquire a lock for the object.