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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 31BBDCA9EAE for ; Tue, 29 Oct 2019 11:13:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0DD7720874 for ; Tue, 29 Oct 2019 11:13:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731670AbfJ2LNd (ORCPT ); Tue, 29 Oct 2019 07:13:33 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:61398 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727020AbfJ2LNc (ORCPT ); Tue, 29 Oct 2019 07:13:32 -0400 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x9TAxqka045400; Tue, 29 Oct 2019 07:13:21 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0b-001b2d01.pphosted.com with ESMTP id 2vxjpk3xmw-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 29 Oct 2019 07:13:21 -0400 Received: from m0098413.ppops.net (m0098413.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.27/8.16.0.27) with SMTP id x9TB0jjZ049636; Tue, 29 Oct 2019 07:13:20 -0400 Received: from ppma01dal.us.ibm.com (83.d6.3fa9.ip4.static.sl-reverse.com [169.63.214.131]) by mx0b-001b2d01.pphosted.com with ESMTP id 2vxjpk3xm7-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 29 Oct 2019 07:13:20 -0400 Received: from pps.filterd (ppma01dal.us.ibm.com [127.0.0.1]) by ppma01dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id x9TBAO0A016392; Tue, 29 Oct 2019 11:13:19 GMT Received: from b01cxnp23034.gho.pok.ibm.com (b01cxnp23034.gho.pok.ibm.com [9.57.198.29]) by ppma01dal.us.ibm.com with ESMTP id 2vvds91be4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 29 Oct 2019 11:13:19 +0000 Received: from b01ledav001.gho.pok.ibm.com (b01ledav001.gho.pok.ibm.com [9.57.199.106]) by b01cxnp23034.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x9TBDInd52560190 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 29 Oct 2019 11:13:18 GMT Received: from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C84842805A; Tue, 29 Oct 2019 11:13:18 +0000 (GMT) Received: from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7428D28059; Tue, 29 Oct 2019 11:13:18 +0000 (GMT) Received: from sofia.ibm.com (unknown [9.199.37.192]) by b01ledav001.gho.pok.ibm.com (Postfix) with ESMTP; Tue, 29 Oct 2019 11:13:18 +0000 (GMT) Received: by sofia.ibm.com (Postfix, from userid 1000) id A873D2E3143; Tue, 29 Oct 2019 16:43:14 +0530 (IST) Date: Tue, 29 Oct 2019 16:43:14 +0530 From: Gautham R Shenoy To: Nathan Lynch Cc: "Gautham R. Shenoy" , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Michael Ellerman , Nicholas Piggin , Tyrel Datwyler , Vaidyanathan Srinivasan , Kamalesh Babulal , "Naveen N. Rao" , "Aneesh Kumar K.V" Subject: Re: [PATCH v2 0/1] pseries/hotplug: Change the default behaviour of cede_offline Message-ID: <20191029111314.GC12266@in.ibm.com> Reply-To: ego@linux.vnet.ibm.com References: <1571740391-3251-1-git-send-email-ego@linux.vnet.ibm.com> <87o8y45sxt.fsf@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87o8y45sxt.fsf@linux.ibm.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-10-29_03:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=901 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910290114 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Nathan, On Fri, Oct 25, 2019 at 06:03:26PM -0500, Nathan Lynch wrote: > "Gautham R. Shenoy" writes: > > This is the v2 of the fix to change the default behaviour of > > cede_offline. > > OK, but why keep the cede offline behavior at all? Can we remove it? I > think doing so would allow us to remove all the code that temporarily > onlines threads for partition migration. May be I am missing something. But don't we want all the CPUs to come online and execute the H_JOIN hcall before performing partition migration? How will this change whether the offlined CPUs are in H_CEDE or rtas-stop-self? -- Thanks and Regards gautham.