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:
Jul. 06, 2021
Filed:
Nov. 13, 2017
International Business Machines Corporation, Armonk, NY (US);
Paul E. McKenney, Beaverton, OR (US);
INTERNATIONAL BUSINESS MACHINES CORPORATION, Armonk, NY (US);
Abstract
A funnel locking technique improves scalability of callback handling while mediating grace-period-start requests in a sleepable read-copy update (SRCU) environment. Per-CPU data structures maintain lists of SRCU callbacks. A management data structure maintains a current-grace-period record tracking a current SRCU grace period and a future-grace-period record tracking a future SRCU grace period needed by the callbacks. A combining tree mediates grace-period-start requests concurrently vying for an opportunity to update the future-grace-period record. The grace-period-start requests are issued on behalf of the callbacks to a combining tree leaf level and propagate toward a combining tree root node. The future-grace-period record is updated in response to grace-period-start requests reaching the root node. The current-grace-period record is updated to start a new SRCU grace period in response to grace-period-start requests reaching the root node if the future SRCU grace period has not completed and there is no SRCU grace period in progress.