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
| ||
|
Date: Thu, 10 Oct 2013 09:43:55 -0700 From: Andrew Morton <akpm@...ux-foundation.org> To: Steven Rostedt <rostedt@...dmis.org> Cc: Oleg Nesterov <oleg@...hat.com>, Ingo Molnar <mingo@...nel.org>, "Srivatsa S. Bhat" <srivatsa.bhat@...ux.vnet.ibm.com>, Peter Zijlstra <peterz@...radead.org>, Paul McKenney <paulmck@...ux.vnet.ibm.com>, Mel Gorman <mgorman@...e.de>, Rik van Riel <riel@...hat.com>, Srikar Dronamraju <srikar@...ux.vnet.ibm.com>, Andrea Arcangeli <aarcange@...hat.com>, Johannes Weiner <hannes@...xchg.org>, Thomas Gleixner <tglx@...utronix.de>, Linus Torvalds <torvalds@...ux-foundation.org>, linux-kernel@...r.kernel.org Subject: Re: [PATCH 0/6] Optimize the cpu hotplug locking -v2 On Thu, 10 Oct 2013 12:36:31 -0400 Steven Rostedt <rostedt@...dmis.org> wrote: > On Thu, 10 Oct 2013 09:00:44 -0700 > Andrew Morton <akpm@...ux-foundation.org> wrote: > > > It's been ages since I looked at this stuff :( Although it isn't used > > much, memory hotplug manages to use stop_machine() on the add/remove > > (ie, "writer") side and nothing at all on the "reader" side. Is there > > anything which fundamentally prevents cpu hotplug from doing the same? > > > I would think that memory hotplug may require stop machine as all CPUs > may touch that memory. Sure. > But we would like to remove stomp machine from > CPU hotplug. We do? That's news. It wasn't mentioned in the changelog and should have been. Why? > Why prevent all CPUs from running when we want to remove > one? So get_online_cpus() goes away. Nothing is more scalable than nothing! -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists