Apple Inc.

Marina Sadini

James Michael Magee

Daniel Allen Chimene

Daniel Andreas Steffen

Jeremy C Andrus

Kushal Dalmia

Jainam Ashokkumar Shah

Pierre Habouzit

A turnstile OS primitive is provided that enables support for owner tracking and waiting. The turnstile primitive enables a common framework that can be adopted across multiple different types of synchronization primitives to provide a common service for priority boosting and wait queuing. A turnstile can also provide a mechanism to enable a turnstile to block on another turnstile, allowing multi-hop priority boosting within a chain of multiple blocking turnstiles.

Turnstile API for runtime priority boosting

One embodiment provides for a computer-implemented method comprising instantiating a synchronization primitive to control access to a resource, acquiring the synchronization primitive at a first thread, the first thread having a first priority, associating a turnstile with the synchronization primitive, setting an inheritor of the turnstile to the first thread, attempting to acquire the synchronization primitive at a second thread while the synchronization primitive is held by the first thread, the second thread having a second priority, adding the second thread to a wait queue of the turnstile; and in response to determining that the second priority is higher than the first priority, increasing the priority of the first thread to the second priority.

Growing community of inventors

Cupertino, CA, United States of America

Marina Sadini