From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753882AbYLOOxk (ORCPT ); Mon, 15 Dec 2008 09:53:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754935AbYLOOxV (ORCPT ); Mon, 15 Dec 2008 09:53:21 -0500 Received: from mtagate7.uk.ibm.com ([195.212.29.140]:35778 "EHLO mtagate7.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754903AbYLOOxU (ORCPT ); Mon, 15 Dec 2008 09:53:20 -0500 Message-Id: <20081215143437.843064041@de.ibm.com> User-Agent: quilt/0.46-1 Date: Mon, 15 Dec 2008 15:34:37 +0100 From: Heiko Carstens To: mingo@elte.hu, akpm@linux-foundation.org Cc: maxk@qualcomm.com, schwidefsky@de.ibm.com, linux-kernel@vger.kernel.org Subject: [PATCH/RESEND 0/2] sched: re-add removed arch_update_cpu_topology call Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This fixes a regression introduced with e761b7725234276a802322549cee5255305a0930 ("cpu hotplug, sched: Introduce cpu_active_map and redo sched domain managment (take 2)": arch_reinit_sched_domains used to call arch_update_cpu_topology via arch_init_sched_domains. This call got lost with the above mentioned patch. So we might end up with outdated and missing cpus in the cpu core maps (s390 used to call arch_reinit_sched_domains if cpu topology changed). This patch set changes arch_update_cpu_topology so that it can indicate if the cpu topology changed and adds a call to arch_update_cpu_topology in partition_sched_domains which gets called whenever scheduling domains get updated. So whenever architecture code detects that cpu topology changed it might force an update of the scheduling domains by calling arch_reinit_sched_domains or rebuild_sched_domains. Besides that the first patch also adds a comment to arch_update_cpu_topology so that its purpose gets described, since most people seem to expect that cpu core mappings are stable which isn't necessarily the case.