linux-kernel - Re: [RFC PATCH v2 3/5] futex: Throughput-optimized (TO) futexes

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <alpine.DEB.2.20.1609221641540.5599@nanos>
Date:   Thu, 22 Sep 2016 16:46:17 +0200 (CEST)
From:   Thomas Gleixner <tglx@...utronix.de>
To:     Davidlohr Bueso <dave@...olabs.net>
cc:     Peter Zijlstra <peterz@...radead.org>,
        Waiman Long <waiman.long@....com>,
        Mike Galbraith <umgwanakikbuti@...il.com>,
        Ingo Molnar <mingo@...nel.org>,
        Jonathan Corbet <corbet@....net>, linux-kernel@...r.kernel.org,
        linux-doc@...r.kernel.org, Jason Low <jason.low2@....com>,
        Scott J Norton <scott.norton@....com>,
        Douglas Hatch <doug.hatch@....com>
Subject: Re: [RFC PATCH v2 3/5] futex: Throughput-optimized (TO) futexes

On Thu, 22 Sep 2016, Davidlohr Bueso wrote:
> On Thu, 22 Sep 2016, Thomas Gleixner wrote:
> > Also what's the reason that we can't do probabilistic spinning for
> > FUTEX_WAIT and have to add yet another specialized variant of futexes?
> 
> Where would this leave the respective FUTEX_WAKE? A nop? Probably have to
> differentiate the fact that the queue was empty, but there was a spinning,
> instead of straightforward returning 0.

Sorry, but I really can't parse this answer.

Can you folks please communicate with proper and coherent explanations
instead of throwing a few gnawed off bones in my direction?

Thanks,

	tglx