Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754417AbZKKKID (ORCPT ); Wed, 11 Nov 2009 05:08:03 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753325AbZKKKIC (ORCPT ); Wed, 11 Nov 2009 05:08:02 -0500 Received: from casper.infradead.org ([85.118.1.10]:52549 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753172AbZKKKIB convert rfc822-to-8bit (ORCPT ); Wed, 11 Nov 2009 05:08:01 -0500 Subject: Re: [BUG] cpu controller can't provide fair CPU time for each group From: Peter Zijlstra To: Yasunori Goto Cc: Miao Xie , Linux-Kernel , containers , Ingo Molnar In-Reply-To: <20091111134910.5F42.E1E9C6FF@jp.fujitsu.com> References: <4AEF94E8.3030403@cn.fujitsu.com> <1257846518.4648.18.camel@twins> <20091111134910.5F42.E1E9C6FF@jp.fujitsu.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Wed, 11 Nov 2009 11:07:28 +0100 Message-ID: <1257934048.23203.76.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.28.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1790 Lines: 57 On Wed, 2009-11-11 at 15:21 +0900, Yasunori Goto wrote: > > Someone needs to fix that if they really care. > > To be honest, I don't have any good idea because I'm not familiar with > schduler's code. You could possible try something like the below, its rather gross but might maybe work,.. has other issues though. --- kernel/sched.c | 9 +++++++-- 1 files changed, 7 insertions(+), 2 deletions(-) diff --git a/kernel/sched.c b/kernel/sched.c index 91642c1..65629a3 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -1614,7 +1614,7 @@ static void update_group_shares_cpu(struct task_group *tg, int cpu, */ static int tg_shares_up(struct task_group *tg, void *data) { - unsigned long weight, rq_weight = 0, shares = 0; + unsigned long weight, rq_weight = 0, sum_weight = 0, shares = 0; unsigned long *usd_rq_weight; struct sched_domain *sd = data; unsigned long flags; @@ -1630,6 +1630,7 @@ static int tg_shares_up(struct task_group *tg, void *data) weight = tg->cfs_rq[i]->load.weight; usd_rq_weight[i] = weight; + rq_weight += weight; /* * If there are currently no tasks on the cpu pretend there * is one of average load so that when a new task gets to @@ -1638,10 +1639,14 @@ static int tg_shares_up(struct task_group *tg, void *data) if (!weight) weight = NICE_0_LOAD; - rq_weight += weight; + sum_weight += weight; + shares += tg->cfs_rq[i]->shares; } + if (!rq_weight) + rq_weight = sum_weight; + if ((!shares && rq_weight) || shares > tg->shares) shares = tg->shares; -- 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/