From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [PATCH] Update sched_domains_numa_masks when new cpus are onlined. Date: Mon, 24 Sep 2012 12:12:08 +0200 Message-ID: <1348481528.11847.29.camel@twins> References: <1347963128-25942-1-git-send-email-tangchen@cn.fujitsu.com> <1348479536.11847.25.camel@twins> <50602E75.1010304@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7BIT Return-path: In-Reply-To: <50602E75.1010304@linux.vnet.ibm.com> Sender: linux-numa-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" To: "Srivatsa S. Bhat" Cc: Tang Chen , linux-kernel@vger.kernel.org, x86@kernel.org, linux-numa@vger.kernel.org, wency@cn.fujitsu.com, mingo@kernel.org, Thomas Gleixner On Mon, 2012-09-24 at 15:27 +0530, Srivatsa S. Bhat wrote: > On 09/24/2012 03:08 PM, Peter Zijlstra wrote: > >> + hotcpu_notifier(sched_domains_numa_masks_update, CPU_PRI_SCHED_ACTIVE); > >> hotcpu_notifier(cpuset_cpu_active, CPU_PRI_CPUSET_ACTIVE); > >> hotcpu_notifier(cpuset_cpu_inactive, CPU_PRI_CPUSET_INACTIVE); > > > > OK, so you really want your notifier to run before cpuset_cpu_active > > because otherwise you get that crash, yet you fail with the whole order > > thing.. You should not _ever_ rely on registration order. > > > > IMHO he isn't relying on registration order.. He uses the CPU_PRI_SCHED_ACTIVE > priority to ensure that the ordering of callbacks is right, isn't it? Oh argh indeed. I can't read :/