From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755981AbbDIRA6 (ORCPT ); Thu, 9 Apr 2015 13:00:58 -0400 Received: from mail-db3on0057.outbound.protection.outlook.com ([157.55.234.57]:52479 "EHLO emea01-db3-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755956AbbDIRAy (ORCPT ); Thu, 9 Apr 2015 13:00:54 -0400 Authentication-Results: spf=fail (sender IP is 12.216.194.146) smtp.mailfrom=ezchip.com; ezchip.com; dkim=none (message not signed) header.d=none; From: Chris Metcalf To: "Peter Zijlstra (Intel)" , Frederic Weisbecker , "Paul E. McKenney" , "Rafael J. Wysocki" , Martin Schwidefsky , Ingo Molnar , CC: Chris Metcalf Subject: [PATCH v4 2/2] nohz: set isolcpus when nohz_full is set Date: Thu, 9 Apr 2015 13:00:39 -0400 Message-ID: <1428598839-24296-2-git-send-email-cmetcalf@ezchip.com> X-Mailer: git-send-email 2.1.2 In-Reply-To: <1428598839-24296-1-git-send-email-cmetcalf@ezchip.com> References: <20150409082921.GP27490@worktop.programming.kicks-ass.net> <1428598839-24296-1-git-send-email-cmetcalf@ezchip.com> X-EOPAttributedMessage: 0 X-Forefront-Antispam-Report: CIP:12.216.194.146;CTRY:US;IPV:NLI;EFV:NLI;BMV:1;SFV:NSPM;SFS:(10009020)(6009001)(339900001)(199003)(189002)(54534003)(47776003)(105606002)(19580395003)(85426001)(106466001)(229853001)(6806004)(86362001)(42186005)(575784001)(87936001)(46102003)(104016003)(92566002)(77156002)(62966003)(76176999)(50226001)(50466002)(36756003)(50986999)(2950100001)(33646002)(48376002);DIR:OUT;SFP:1101;SCL:1;SRVR:HE1PR02MB0778;H:ld-1.internal.tilera.com;FPR:;SPF:Fail;MLV:sfv;A:1;MX:1;LANG:en; MIME-Version: 1.0 Content-Type: text/plain X-Microsoft-Antispam: UriScan:;BCL:0;PCL:0;RULEID:;SRVR:HE1PR02MB0778; X-Microsoft-Antispam-PRVS: X-Exchange-Antispam-Report-Test: UriScan:; X-Exchange-Antispam-Report-CFA-Test: BCL:0;PCL:0;RULEID:(601004)(5002010)(5005006);SRVR:HE1PR02MB0778;BCL:0;PCL:0;RULEID:;SRVR:HE1PR02MB0778; X-Forefront-PRVS: 0541031FF6 X-OriginatorOrg: ezchip.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Apr 2015 17:00:48.9786 (UTC) X-MS-Exchange-CrossTenant-Id: 0fc16e0a-3cd3-4092-8b2f-0a42cff122c3 X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=0fc16e0a-3cd3-4092-8b2f-0a42cff122c3;Ip=[12.216.194.146];Helo=[ld-1.internal.tilera.com] X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: HE1PR02MB0778 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org nohz_full is only useful with isolcpus also set, since otherwise the scheduler has to run periodically to try to determine whether to steal work from other cores. Accordingly, when booting with nohz_full=xxx on the command line, we should act as if isolcpus=xxx was also set, and set (or extend) the isolcpus set to include the nohz_full cpus. Signed-off-by: Chris Metcalf Acked-by: Mike Galbraith ["thumbs up!"] Acked-by: Rik van Riel --- v4: update accessor names to make them clearer [PeterZ] v3: update changelog language to avoid using unclear "implies" [PeterZ] kernel/sched/core.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index f0f831e8a345..f8bce1b24cf3 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6836,6 +6836,7 @@ static int init_sched_domains(const struct cpumask *cpu_map) doms_cur = alloc_sched_domains(ndoms_cur); if (!doms_cur) doms_cur = &fallback_doms; + tick_nohz_full_cpumask_or(cpu_isolated_map); cpumask_andnot(doms_cur[0], cpu_map, cpu_isolated_map); err = build_sched_domains(doms_cur[0], NULL); register_sched_domain_sysctl(); -- 2.1.2