Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161232AbWJRQpR (ORCPT ); Wed, 18 Oct 2006 12:45:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1161233AbWJRQpQ (ORCPT ); Wed, 18 Oct 2006 12:45:16 -0400 Received: from pollux.ds.pg.gda.pl ([153.19.208.7]:56073 "EHLO pollux.ds.pg.gda.pl") by vger.kernel.org with ESMTP id S1161232AbWJRQpO (ORCPT ); Wed, 18 Oct 2006 12:45:14 -0400 Date: Wed, 18 Oct 2006 17:45:12 +0100 (BST) From: "Maciej W. Rozycki" To: Andi Kleen cc: john stultz , lkml Subject: Re: [PATCH] i386 Time: Avoid PIT SMP lockups In-Reply-To: Message-ID: References: <1160596462.5973.12.camel@localhost.localdomain> <20061011142646.eb41fac3.akpm@osdl.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 875 Lines: 22 On Wed, 18 Oct 2006, Andi Kleen wrote: > It wouldn't work on dual core laptop chipsets which support C3 and where > the APIC timer stops during C3. > > I had a apicrunsmaintimer option for some time on x86-64 but it broke > on a few other non laptop machines for unknown reasons too, so I cannot > really recommend it. So they managed to break it too? Oh well... If you look at early APIC documentation, then you'll see how the APIC timers were recommended to be the only source of the clock tick for SMP systems in favour to the old-fashioned PIT. Now, how can it be used if it does not run all the time?... Maciej - 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/