From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, T_DKIMWL_WL_HIGH,UNPARSEABLE_RELAY,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 107FEC43141 for ; Thu, 28 Jun 2018 22:44:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AA8C627821 for ; Thu, 28 Jun 2018 22:44:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="PjhfDh4u" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AA8C627821 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=oracle.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967051AbeF1WoE (ORCPT ); Thu, 28 Jun 2018 18:44:04 -0400 Received: from aserp2130.oracle.com ([141.146.126.79]:49746 "EHLO aserp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964786AbeF1Wn5 (ORCPT ); Thu, 28 Jun 2018 18:43:57 -0400 Received: from pps.filterd (aserp2130.oracle.com [127.0.0.1]) by aserp2130.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w5SMcu9I071628; Thu, 28 Jun 2018 22:43:24 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references; s=corp-2017-10-26; bh=T0yaG9ciUukEyvK2f0cZ03RZkhvc+EAbx0OcpNZfKU4=; b=PjhfDh4u5D6US2ZNSih75qGWQ2mJYswh4ce9Q6QR86w8Wz6LGG7Qt17Zv+KQ/jy/C7q7 K8iLQ2dJHa2z5cEB4MG8IjN5k6dj01XQLdVyUlGz2wz0UWZ4KJIyW53dBYfWSkNm5GEd 2ltG2R3DwBLxgkGVCTW+Gmt7Mn4eTYixUbjw6sgUNAoyi8tpl1RkffhILfDt4te3QZmp KnzrYGCZx4WWC1hoGNy2Se7YWua583vNJ1KcrjBrslyblYV8aRh5QArML1tVsRYQM128 /BljigkBViswFAWO3d5F0UanMeFs6HD+/rb9bFai3utkLr7wHuYVXWt5qX/bhc16/0Jc Ow== Received: from userv0021.oracle.com (userv0021.oracle.com [156.151.31.71]) by aserp2130.oracle.com with ESMTP id 2jukmu49rv-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 28 Jun 2018 22:43:24 +0000 Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by userv0021.oracle.com (8.14.4/8.14.4) with ESMTP id w5SMhNHA012773 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 28 Jun 2018 22:43:23 GMT Received: from abhmp0018.oracle.com (abhmp0018.oracle.com [141.146.116.24]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id w5SMhNom023374; Thu, 28 Jun 2018 22:43:23 GMT Received: from smazumda-Precision-T1600.us.oracle.com (/10.132.91.87) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 28 Jun 2018 15:43:23 -0700 From: subhra mazumdar To: linux-kernel@vger.kernel.org Cc: peterz@infradead.org, mingo@redhat.com, steven.sistare@oracle.com, dhaval.giani@oracle.com, rohit.k.jain@oracle.com, daniel.lezcano@linaro.org Subject: [PATCH 5/5] sched: SIS_CORE to disable idle core search Date: Thu, 28 Jun 2018 15:44:56 -0700 Message-Id: <20180628224456.13548-6-subhra.mazumdar@oracle.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20180628224456.13548-1-subhra.mazumdar@oracle.com> References: <20180628224456.13548-1-subhra.mazumdar@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8938 signatures=668703 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=1 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=395 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1806210000 definitions=main-1806280249 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Use SIS_CORE to disable idle core search. For some workloads select_idle_core becomes a scalability bottleneck, removing it improves throughput. Also there are workloads where disabling it can hurt latency, so need to have an option. Signed-off-by: subhra mazumdar --- kernel/sched/fair.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 574cb14..33fbc47 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6464,9 +6464,11 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target) if (!sd) return target; - i = select_idle_core(p, sd, target); - if ((unsigned)i < nr_cpumask_bits) - return i; + if (sched_feat(SIS_CORE)) { + i = select_idle_core(p, sd, target); + if ((unsigned)i < nr_cpumask_bits) + return i; + } i = select_idle_cpu(p, sd, target); if ((unsigned)i < nr_cpumask_bits) -- 2.9.3