From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760470Ab1D1OUx (ORCPT ); Thu, 28 Apr 2011 10:20:53 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:52688 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760010Ab1D1OUw convert rfc822-to-8bit (ORCPT ); Thu, 28 Apr 2011 10:20:52 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 From: KOSAKI Motohiro To: LKML , Andrew Morton , Oleg Nesterov , Peter Zijlstra , Ingo Molnar , Li Zefan , Miao Xie Subject: [RFC PATCH] cpuset: fix cpuset_cpus_allowed_fallback() don't update tsk->rt.nr_cpus_allowed Cc: kosaki.motohiro@jp.fujitsu.com Message-Id: <20110428232228.3D57.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 8BIT X-Mailer: Becky! ver. 2.56.05 [ja] Date: Thu, 28 Apr 2011 23:20:50 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Oleg, Peter, I apologize if I misunderstand a code. I'm afraid we need following patch. Is there any gurantte that cpusets user task is not RT task? >>From 400e24f7b6e15d1397dc82d74fdd1e0a631493ef Mon Sep 17 00:00:00 2001 From: KOSAKI Motohiro Date: Thu, 28 Apr 2011 16:14:16 +0900 Subject: [PATCH] cpuset: fix cpuset_cpus_allowed_fallback() don't update tsk->rt.nr_cpus_allowed The rule is, we have to update tsk->rt.nr_cpus_allowed too if we change tsk->cpus_allowed. Signed-off-by: KOSAKI Motohiro Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Ingo Molnar --- include/linux/cpuset.h | 1 + kernel/cpuset.c | 1 + 2 files changed, 2 insertions(+), 0 deletions(-) diff --git a/include/linux/cpuset.h b/include/linux/cpuset.h index f20eb8f..42dcbdc 100644 --- a/include/linux/cpuset.h +++ b/include/linux/cpuset.h @@ -147,6 +147,7 @@ static inline void cpuset_cpus_allowed(struct task_struct *p, static inline int cpuset_cpus_allowed_fallback(struct task_struct *p) { cpumask_copy(&p->cpus_allowed, cpu_possible_mask); + p->rt.nr_cpus_allowed = cpumask_weight(&p->cpus_allowed); return cpumask_any(cpu_active_mask); } diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 1ceeb04..6e5bbe8 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -2220,6 +2220,7 @@ int cpuset_cpus_allowed_fallback(struct task_struct *tsk) cpumask_copy(&tsk->cpus_allowed, cpu_possible_mask); cpu = cpumask_any(cpu_active_mask); } + tsk->rt.nr_cpus_allowed = cpumask_weight(&tsk->cpus_allowed); return cpu; } -- 1.7.3.1