linux-kernel - Re: [PATCH tip/core/rcu 4/5] sys_membarrier: Add expedited option

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: <20170727102422.dgaq7qqkpikvue4l@hirez.programming.kicks-ass.net>
Date:   Thu, 27 Jul 2017 12:24:22 +0200
From:   Peter Zijlstra <peterz@...radead.org>
To:     "Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>
Cc:     Mathieu Desnoyers <mathieu.desnoyers@...icios.com>,
        linux-kernel <linux-kernel@...r.kernel.org>,
        Ingo Molnar <mingo@...nel.org>,
        Lai Jiangshan <jiangshanlai@...il.com>,
        dipankar <dipankar@...ibm.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Josh Triplett <josh@...htriplett.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        rostedt <rostedt@...dmis.org>,
        David Howells <dhowells@...hat.com>,
        Eric Dumazet <edumazet@...gle.com>,
        fweisbec <fweisbec@...il.com>, Oleg Nesterov <oleg@...hat.com>,
        Will Deacon <will.deacon@....com>
Subject: Re: [PATCH tip/core/rcu 4/5] sys_membarrier: Add expedited option

On Wed, Jul 26, 2017 at 11:30:32AM -0700, Paul E. McKenney wrote:
> The patch I posted reverts to synchronize_sched() in kernels booted with
> rcupdate.rcu_normal=1.  ;-)

So boot parameters are no solution and are only slightly better than
compile time switches.

What if you have a machine that runs workloads that want both options?
partitioning and containers are somewhat popular these days and system
wide tunables don't work for them.