Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752656Ab1E0Rzd (ORCPT ); Fri, 27 May 2011 13:55:33 -0400 Received: from caramon.arm.linux.org.uk ([78.32.30.218]:37264 "EHLO caramon.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751353Ab1E0Rzc (ORCPT ); Fri, 27 May 2011 13:55:32 -0400 Date: Fri, 27 May 2011 18:55:00 +0100 From: Russell King - ARM Linux To: Ingo Molnar Cc: Catalin Marinas , Peter Zijlstra , Marc Zyngier , Frank Rowand , Oleg Nesterov , linux-kernel@vger.kernel.org, Yong Zhang , linux-arm-kernel@lists.infradead.org Subject: Re: [BUG] "sched: Remove rq->lock from the first half of ttwu()" locks up on ARM Message-ID: <20110527175500.GQ24876@n2100.arm.linux.org.uk> References: <1306405979.1200.63.camel@twins> <1306407759.27474.207.camel@e102391-lin.cambridge.arm.com> <1306409575.1200.71.camel@twins> <1306412511.1200.90.camel@twins> <20110526122623.GA11875@elte.hu> <20110526123137.GG24876@n2100.arm.linux.org.uk> <20110526125007.GA27083@elte.hu> <20110527120629.GA32617@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110527120629.GA32617@elte.hu> User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1085 Lines: 21 On Fri, May 27, 2011 at 02:06:29PM +0200, Ingo Molnar wrote: > I'd suggest doing this once modern ARM chips get so widespread that > you can realistically induce a ~700 usecs irqs-off delays on old, > virtual-cache ARM chips. Old chips would likely use old kernels > anyway, right? Not necessarily. I have rather a lot of legacy hardware (it outweighs the more modern stuff) and that legacy hardware is _loads_ more useful than the modern stuff in that it can actually do stuff like run a network (such as running kerberos servers, httpd, mtas, etc). Modern ARM machines typically don't have ways to attach mass storage to them which make them hellishly limited for such applications. I'm planning to continue using my old machines, and continue to upgrade their kernels, especially in order to keep up to date with security issues. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/