Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758262AbYGODXU (ORCPT ); Mon, 14 Jul 2008 23:23:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753238AbYGODXN (ORCPT ); Mon, 14 Jul 2008 23:23:13 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.123]:49701 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750715AbYGODXM (ORCPT ); Mon, 14 Jul 2008 23:23:12 -0400 Date: Mon, 14 Jul 2008 23:23:09 -0400 (EDT) From: Steven Rostedt X-X-Sender: rostedt@gandalf.stny.rr.com To: Linus Torvalds cc: Dmitry Adamushko , Vegard Nossum , Paul Menage , Max Krasnyansky , Paul Jackson , Peter Zijlstra , miaox@cn.fujitsu.com, Thomas Gleixner , Ingo Molnar , Linux Kernel Subject: Re: current linux-2.6.git: cpusets completely broken In-Reply-To: Message-ID: References: <20080712031736.GA3040@damson.getinternet.no> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 830 Lines: 20 On Mon, 14 Jul 2008, Linus Torvalds wrote: > So by doing the test for cpu_active_map not at queuing time, but at the > time when we actually try to do the migration, we can now also make that > cpu_active_map be totally serialized. > > (Of course, anybody who clears the bit does need to take the runqueue lock > of that CPU too, but cpu_down() will have to do that as it does the > "migrate away live tasks" anyway, so that's not a problem) Wouldn't simply doing a synchronize_sched() after clearing the bit also make sure that no new task will be scheduled on that CPU? -- Steve -- 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/