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=-2.5 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 EB6B7C49ED7 for ; Fri, 13 Sep 2019 05:47:07 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2230B21479 for ; Fri, 13 Sep 2019 05:47:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2230B21479 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.vnet.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 46V4Qb0K1vzF58j for ; Fri, 13 Sep 2019 15:47:03 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=none (mailfrom) smtp.mailfrom=linux.vnet.ibm.com (client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com; envelope-from=srikar@linux.vnet.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.vnet.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 46V4NG6b1tzF3s3 for ; Fri, 13 Sep 2019 15:45:02 +1000 (AEST) Received: from pps.filterd (m0098396.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x8D5bGvI076887 for ; Fri, 13 Sep 2019 01:44:59 -0400 Received: from e06smtp05.uk.ibm.com (e06smtp05.uk.ibm.com [195.75.94.101]) by mx0a-001b2d01.pphosted.com with ESMTP id 2v03x325n1-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 13 Sep 2019 01:44:59 -0400 Received: from localhost by e06smtp05.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 13 Sep 2019 06:44:57 +0100 Received: from b06cxnps3074.portsmouth.uk.ibm.com (9.149.109.194) by e06smtp05.uk.ibm.com (192.168.101.135) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Fri, 13 Sep 2019 06:44:54 +0100 Received: from d06av24.portsmouth.uk.ibm.com (mk.ibm.com [9.149.105.60]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x8D5irlp32309396 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 13 Sep 2019 05:44:54 GMT Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C881C4204B; Fri, 13 Sep 2019 05:44:53 +0000 (GMT) Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A319042042; Fri, 13 Sep 2019 05:44:52 +0000 (GMT) Received: from linux.vnet.ibm.com (unknown [9.122.211.212]) by d06av24.portsmouth.uk.ibm.com (Postfix) with SMTP; Fri, 13 Sep 2019 05:44:52 +0000 (GMT) Date: Fri, 13 Sep 2019 11:14:51 +0530 From: Srikar Dronamraju To: Nathan Lynch Subject: Re: [PATCH v3 3/5] powerpc/numa: Use cpu node map of first sibling thread References: <20190906135020.19772-1-srikar@linux.vnet.ibm.com> <20190906135020.19772-4-srikar@linux.vnet.ibm.com> <87lfuurirh.fsf@linux.ibm.com> <20190911165845.GA31643@linux.vnet.ibm.com> <87ftl1qxey.fsf@linux.ibm.com> <20190912171751.GA16497@linux.vnet.ibm.com> <87d0g5qt3s.fsf@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <87d0g5qt3s.fsf@linux.ibm.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-TM-AS-GCONF: 00 x-cbid: 19091305-0020-0000-0000-0000036BB946 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19091305-0021-0000-0000-000021C14E37 Message-Id: <20190913021649.GA23865@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-09-13_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=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1909130057 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Srikar Dronamraju Cc: Satheesh Rajendran , linuxppc-dev , Nicholas Piggin Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" * Nathan Lynch [2019-09-12 13:15:03]: > Srikar Dronamraju writes: > > >> > >> I think just WARN_ON(cpu_online(fcpu)) would be satisfactory. In my > >> experience, the downstream effects of violating this condition are > >> varied and quite difficult to debug. Seems only appropriate to emit a > >> warning and stack trace before the OS inevitably becomes unstable. > > > > I still have to try but wouldn't this be a problem for the boot-cpu? > > I mean boot-cpu would be marked online while it tries to do numa_setup_cpu. > > No? > > This is what I mean: > > + if (fcpu != lcpu) { > + WARN_ON(cpu_online(fcpu)); > + map_cpu_to_node(fcpu, nid); > + } > Yes this should work. Will send an updated patch with this change. > I.e. if we're modifying the mapping for a remote cpu, warn if it's > online. > > I don't think this would warn on the boot cpu -- I would expect fcpu and > lcpu to be the same and this branch would not be taken. -- Thanks and Regards Srikar Dronamraju