From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262116AbVFRN4R (ORCPT ); Sat, 18 Jun 2005 09:56:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262117AbVFRN4R (ORCPT ); Sat, 18 Jun 2005 09:56:17 -0400 Received: from ipx10786.ipxserver.de ([80.190.251.108]:55769 "EHLO allen.werkleitz.de") by vger.kernel.org with ESMTP id S262116AbVFRN4O (ORCPT ); Sat, 18 Jun 2005 09:56:14 -0400 Date: Sat, 18 Jun 2005 15:57:52 +0200 From: Johannes Stezenbach To: Bill Davidsen Cc: Linus Torvalds , Kernel Mailing List Message-ID: <20050618135752.GB19838@linuxtv.org> Mail-Followup-To: Johannes Stezenbach , Bill Davidsen , Linus Torvalds , Kernel Mailing List References: <20050607091144.GA5701@linuxtv.org> <20050608111503.GA5777@linuxtv.org> <42A6D521.606@ens-lyon.org> <20050608113718.GA5949@linuxtv.org> <42B30CE9.4050707@tmr.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <42B30CE9.4050707@tmr.com> User-Agent: Mutt/1.5.9i X-SA-Exim-Connect-IP: 84.189.217.46 Subject: Re: Linux v2.6.12-rc6 X-SA-Exim-Version: 4.2 (built Thu, 03 Mar 2005 10:44:12 +0100) X-SA-Exim-Scanned: Yes (on allen.werkleitz.de) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Bill Davidsen wrote: > Johannes Stezenbach wrote: > >Brice Goglin wrote: > >>Johannes Stezenbach a écrit : > >>>Indeed SMT works fine if I enable ACPI. > >>>Is SMT without ACPI not supported? > >> > >>You can pass acpi=ht into the kernel command line to disable > >>ACPI except the minimum required to get HT support. > > > > > >That's nice, but I was thinking along the lines of: > > > >diff -ur linux-2.6.12-rc6.orig/arch/i386/Kconfig > >linux-2.6.12-rc6/arch/i386/Kconfig > >--- linux-2.6.12-rc6.orig/arch/i386/Kconfig 2005-06-06 > >23:16:27.000000000 +0200 > >+++ linux-2.6.12-rc6/arch/i386/Kconfig 2005-06-08 > >13:35:08.000000000 +0200 > >@@ -503,7 +503,7 @@ > > > > config SCHED_SMT > > bool "SMT (Hyperthreading) scheduler support" > >- depends on SMP > >+ depends on SMP && ACPI > > default off > > help > > SMT scheduler support improves the CPU scheduler's decision making > > > >Comments? Is this intended? > > I would think that you can't do HT without ACPI, so there's no point in > building in HT scheduling unless you can have HT. > > Is that what you were asking? I was hoping someone else would comment. In 2.6.12-rc5 SMT worked without CONFIG_ACPI. (IIRC the kernel used some minimal ACPI stuff anyway for CPU initialisation). I don't use power management or other features of ACPI so I had it disabled, and my build broke with 2.6.12-rc6. Johannes