From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752040AbZHJITu (ORCPT ); Mon, 10 Aug 2009 04:19:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751668AbZHJITu (ORCPT ); Mon, 10 Aug 2009 04:19:50 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:36735 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751606AbZHJITt (ORCPT ); Mon, 10 Aug 2009 04:19:49 -0400 Date: Mon, 10 Aug 2009 10:19:41 +0200 From: Pavel Machek To: "Rafael J. Wysocki" Cc: Shaohua Li , Gautham R Shenoy , Joel Schopp , "Brown, Len" , Peter Zijlstra , Balbir Singh , "Pallipadi, Venkatesh" , Benjamin Herrenschmidt , Ingo Molnar , Vaidyanathan Srinivasan , Dipankar Sarma , "Darrick J. Wong" , "linuxppc-dev@lists.ozlabs.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 0/3] cpu: idle state framework for offline CPUs. Message-ID: <20090810081941.GA18649@elf.ucw.cz> References: <20090805142311.553.78286.stgit@sofia.in.ibm.com> <20090806015855.GA20596@sli10-desk.sh.intel.com> <20090809120818.GA1338@ucw.cz> <200908091522.02898.rjw@sisk.pl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200908091522.02898.rjw@sisk.pl> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun 2009-08-09 15:22:02, Rafael J. Wysocki wrote: > On Sunday 09 August 2009, Pavel Machek wrote: > > Hi! > > > > > > Also, approaches such as [1] can make use of this > > > > extended infrastructure instead of putting the CPU to an arbitrary C-state > > > > when it is offlined, thereby providing the system administrator a rope to hang > > > > himself with should he feel the need to do so. > > > I didn't see the reason why administrator needs to know which state offline cpu > > > should stay. Don't know about powerpc side, but in x86 side, it appears deepest > > > C-state is already preferred. > > > > > > > Agreed, deepest c-state is always best, there's no need to make it configurable. > > Unless it doesn't work. If it does not work, machine will not boot. We already have max_cstate= kernel command line option to work around that... Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html