Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754195AbbGAPrt (ORCPT ); Wed, 1 Jul 2015 11:47:49 -0400 Received: from mail-wi0-f181.google.com ([209.85.212.181]:33758 "EHLO mail-wi0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753137AbbGAPrk (ORCPT ); Wed, 1 Jul 2015 11:47:40 -0400 Message-ID: <1435765657.2863.14.camel@gmail.com> Subject: Re: [PATCH?] Livelock in pick_next_task_fair() / idle_balance() From: Mike Galbraith To: Rabin Vincent Cc: "mingo@redhat.com" , "peterz@infradead.org" , "linux-kernel@vger.kernel.org" Date: Wed, 01 Jul 2015 17:47:37 +0200 In-Reply-To: <20150701145551.GA15690@axis.com> References: <20150630143057.GA31689@axis.com> <1435728995.9397.7.camel@gmail.com> <20150701145551.GA15690@axis.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.11 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 777 Lines: 20 On Wed, 2015-07-01 at 16:55 +0200, Rabin Vincent wrote: > So, we will not hit the "if (env->src_rq->load.weight <= > env->dst_rq->load.weight + d_load)" condition to break out of the loop until we > actualy move all tasks. So the patch will not have any effect on this case. > Or am I missing something? Probably not. I did have it breaking if dst_rq would pass src_rq->nr_running, which would certainly stop it, but thought I try to let it watch weights. Either way, task_h_load(p) returning 0 is not very wonderful. -Mike -- 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/