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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 5C231C4CEC4 for ; Wed, 18 Sep 2019 17:08:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3A6A220665 for ; Wed, 18 Sep 2019 17:08:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731109AbfIRRI6 (ORCPT ); Wed, 18 Sep 2019 13:08:58 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:49386 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727243AbfIRRI6 (ORCPT ); Wed, 18 Sep 2019 13:08:58 -0400 Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x8IH22vn038322; Wed, 18 Sep 2019 13:08:47 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 2v3rdbrpk4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 18 Sep 2019 13:08:47 -0400 Received: from m0098399.ppops.net (m0098399.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.27/8.16.0.27) with SMTP id x8IH3QWk042500; Wed, 18 Sep 2019 13:08:47 -0400 Received: from ppma04wdc.us.ibm.com (1a.90.2fa9.ip4.static.sl-reverse.com [169.47.144.26]) by mx0a-001b2d01.pphosted.com with ESMTP id 2v3rdbrpja-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 18 Sep 2019 13:08:47 -0400 Received: from pps.filterd (ppma04wdc.us.ibm.com [127.0.0.1]) by ppma04wdc.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id x8IGxX68002888; Wed, 18 Sep 2019 17:08:46 GMT Received: from b03cxnp08026.gho.boulder.ibm.com (b03cxnp08026.gho.boulder.ibm.com [9.17.130.18]) by ppma04wdc.us.ibm.com with ESMTP id 2v37jw6xmv-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 18 Sep 2019 17:08:45 +0000 Received: from b03ledav002.gho.boulder.ibm.com (b03ledav002.gho.boulder.ibm.com [9.17.130.233]) by b03cxnp08026.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x8IH8i9a60293628 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 18 Sep 2019 17:08:44 GMT Received: from b03ledav002.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 4DF3E136067; Wed, 18 Sep 2019 17:08:44 +0000 (GMT) Received: from b03ledav002.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3436B136059; Wed, 18 Sep 2019 17:08:44 +0000 (GMT) Received: from localhost (unknown [9.41.179.186]) by b03ledav002.gho.boulder.ibm.com (Postfix) with ESMTP; Wed, 18 Sep 2019 17:08:44 +0000 (GMT) From: Nathan Lynch To: Gautham R Shenoy Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Vaidyanathan Srinivasan , Kamalesh Babulal , "Naveen N . Rao" , "Aneesh Kumar K.V" , Michael Ellerman , Nicholas Piggin , Tyrel Datwyler Subject: Re: [PATCH 0/2] pseries/hotplug: Change the default behaviour of cede_offline In-Reply-To: <20190918123039.GA12534@in.ibm.com> References: <1568284541-15169-1-git-send-email-ego@linux.vnet.ibm.com> <87impxr0am.fsf@linux.ibm.com> <20190915074217.GA943@in.ibm.com> <87a7b2rfj0.fsf@linux.ibm.com> <20190918123039.GA12534@in.ibm.com> Date: Wed, 18 Sep 2019 12:08:43 -0500 Message-ID: <874l19r0pw.fsf@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-09-18_09:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=998 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1909180158 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Gautham R Shenoy writes: > The accounting problem in tools such as lparstat with > "cede_offline=on" is affecting customers who are using these tools for > capacity-planning. That problem needs a fix in the short-term, for > which Patch 1 changes the default behaviour of cede_offline from "on" > to "off". Since this patch would break the existing userspace tools > that use the CPU-Offline infrastructure to fold CPUs for saving power, > the sysfs interface allowing a runtime change of cede_offline_enabled > was provided to enable these userspace tools to cope with minimal > change. So we would be putting users in the position of choosing between folding and correct accounting. :-( Actually how does changing the offline mechanism to stop-self break the folding utility?