linux-kernel - Re: [PATCH 2/2] smp_call_function: use rwlocks on queues rather than rcu

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: <48B2D343.4020100@linux-foundation.org>
Date:	Mon, 25 Aug 2008 10:44:03 -0500
From:	Christoph Lameter <cl@...ux-foundation.org>
To:	paulmck@...ux.vnet.ibm.com
CC:	Peter Zijlstra <peterz@...radead.org>,
	Pekka Enberg <penberg@...helsinki.fi>,
	Ingo Molnar <mingo@...e.hu>,
	Jeremy Fitzhardinge <jeremy@...p.org>,
	Nick Piggin <nickpiggin@...oo.com.au>,
	Andi Kleen <andi@...stfloor.org>,
	"Pallipadi, Venkatesh" <venkatesh.pallipadi@...el.com>,
	Suresh Siddha <suresh.b.siddha@...el.com>,
	Jens Axboe <jens.axboe@...cle.com>,
	Rusty Russell <rusty@...tcorp.com.au>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 2/2] smp_call_function: use rwlocks on queues rather	than
 rcu

Paul E. McKenney wrote:

> But I am not sure that this gets the grace periods to go fast enough to
> cover Christoph's use case -- he seems to be in a "faster is better"
> space rather than in an "at least this fast" space.  Still, it would
> likely help in some important cases.

I think there was an AIM9 regression in the close/open tests when the struct
file was switched to RCU. That test could be run with various intervals to
figure out if a shorter RCU period is beneficial and how short an RCU period
is needed to avoid the regression.


--
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/