Public bug reported: Will Deacon proposed the RELEASE/ACQUIRE/RELAXED semantics for atomic operations(https://lkml.org/lkml/2015/8/6/498), which has been already merged in 4.3-rc1. More people tend to use it for better performance(https://lkml.org/lkml/2015/9/20/47). These semantics are proposed for better fitting the need of high scalability.
However, the efficient implementation hasn't been merged yet. As we have a weaker memory order model on POWER, if we didn't implement these atomics efficently, there would be no benefit we can gain from these new operations. A proposal of an efficient implemenation has been sent out to upstream(https://lkml.org/lkml/2015/9/16/527), hopefully will get merged. Still there may be more atomics having RELEASE and ACQUIRE semantics, and there need more effort to implement them correctly. Also, we need to spread these new atomic variants to LTC kernel team to understand what they can provide and how to use them. > Was this feature already accepted upstream? Not yet, still waiting to get into the maintainer's tree, but there is no obvious objection to this feature. ** Affects: ubuntu Importance: Undecided Assignee: Taco Screen team (taco-screen-team) Status: New ** Tags: architecture-ppc64le bugnameltc-136580 severity-medium targetmilestone-inin16041 ** Tags added: architecture-ppc64le bugnameltc-136580 severity-medium targetmilestone-inin16041 ** Changed in: ubuntu Assignee: (unassigned) => Taco Screen team (taco-screen-team) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1556096 Title: [Ubuntu 16.04.1] RELEASE and ACQUIRE atomics on Power To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+bug/1556096/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
