From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261311AbTLHSVt (ORCPT ); Mon, 8 Dec 2003 13:21:49 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261326AbTLHSVs (ORCPT ); Mon, 8 Dec 2003 13:21:48 -0500 Received: from mx1.elte.hu ([157.181.1.137]:156 "EHLO mx1.elte.hu") by vger.kernel.org with ESMTP id S261311AbTLHSVq (ORCPT ); Mon, 8 Dec 2003 13:21:46 -0500 Date: Mon, 8 Dec 2003 19:21:14 +0100 (CET) From: Ingo Molnar Reply-To: Ingo Molnar To: William Lee Irwin III Cc: linux-kernel , Anton Blanchard Subject: Re: [patch] sched-HT-2.6.0-test11-A5 In-Reply-To: <20031208175622.GY19856@holomorphy.com> Message-ID: References: <20031117021511.GA5682@averell> <1027750000.1069604762@[10.10.2.4]> <20031208175622.GY19856@holomorphy.com> 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 On Mon, 8 Dec 2003, William Lee Irwin III wrote: > This appears to either leak migration threads or not set > rq->cpu[x].migration_thread basically ever for x > 0. Or if they are > shut down, how? Also, what makes sure cpu_idx is initialized before they > wake? They'll all spin on cpu_rq(0)->lock, no? yep, it just leaks migration threads. Not a big problem right now, but for hotplug CPU support this needs to be fixed. > Furthermore, sched_map_runqueue() is performed after all the idle > threads are running and all the notifiers have kicked the migration > threads, but does no locking whatsoever. yep - at this point nothing else is really supposed to run but you are right it must be locked properly. > Also, does init_idle() need to move into rest_init()? It should be > equivalent to its current placement. this is a leftover of a change that went into 2.6 already. I've removed this change. > Why not per_cpu for __rq_idx[] and __cpu_idx[]? This would have the > advantage of residing on node-local memory for sane architectures (and > perhaps in the future, some insane ones). agreed, i've changed them to be per-cpu. new patch with all your suggestions included is at: redhat.com/~mingo/O(1)-scheduler/sched-SMT-2.6.0-test11-C1 it also includes the bounce-to-cpu1 fix from/for Anton. Ingo