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=-3.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 E3394C28CBC for ; Fri, 1 May 2020 03:12:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C922820656 for ; Fri, 1 May 2020 03:12:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728133AbgEADMB (ORCPT ); Thu, 30 Apr 2020 23:12:01 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:35406 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727889AbgEADMA (ORCPT ); Thu, 30 Apr 2020 23:12:00 -0400 Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 041337oG155241; Thu, 30 Apr 2020 23:11:41 -0400 Received: from ppma02fra.de.ibm.com (47.49.7a9f.ip4.static.sl-reverse.com [159.122.73.71]) by mx0a-001b2d01.pphosted.com with ESMTP id 30r7m25m6w-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 30 Apr 2020 23:11:41 -0400 Received: from pps.filterd (ppma02fra.de.ibm.com [127.0.0.1]) by ppma02fra.de.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 0412txPY006271; Fri, 1 May 2020 03:11:39 GMT Received: from b06avi18878370.portsmouth.uk.ibm.com (b06avi18878370.portsmouth.uk.ibm.com [9.149.26.194]) by ppma02fra.de.ibm.com with ESMTP id 30mcu7y4sv-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 01 May 2020 03:11:39 +0000 Received: from d06av25.portsmouth.uk.ibm.com (d06av25.portsmouth.uk.ibm.com [9.149.105.61]) by b06avi18878370.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 0413BbGL61931826 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 1 May 2020 03:11:37 GMT Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0CAC011C050; Fri, 1 May 2020 03:11:37 +0000 (GMT) Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0EA8511C04A; Fri, 1 May 2020 03:11:34 +0000 (GMT) Received: from srikart450.in.ibm.com (unknown [9.199.43.214]) by d06av25.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 1 May 2020 03:11:33 +0000 (GMT) From: Srikar Dronamraju To: Andrew Morton Cc: Srikar Dronamraju , linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Michal Hocko , Mel Gorman , Vlastimil Babka , "Kirill A. Shutemov" , Christopher Lameter , Michael Ellerman , Linus Torvalds , Gautham R Shenoy Subject: [PATCH v3 0/3] Offline memoryless cpuless node 0 Date: Fri, 1 May 2020 08:41:25 +0530 Message-Id: <20200501031128.19584-1-srikar@linux.vnet.ibm.com> X-Mailer: git-send-email 2.17.1 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.676 definitions=2020-04-30_13:2020-04-30,2020-04-30 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 mlxscore=0 clxscore=1015 mlxlogscore=804 phishscore=0 impostorscore=0 priorityscore=1501 adultscore=0 lowpriorityscore=0 suspectscore=0 bulkscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2005010021 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Changelog v2:->v3: - Resolved comments from Gautham. Link v2: https://lore.kernel.org/linuxppc-dev/20200428093836.27190-1-srikar@linux.vnet.ibm.com/t/#u Changelog v1:->v2: - Rebased to v5.7-rc3 - Updated the changelog. Link v1: https://lore.kernel.org/linuxppc-dev/20200311110237.5731-1-srikar@linux.vnet.ibm.com/t/#u Linux kernel configured with CONFIG_NUMA on a system with multiple possible nodes, marks node 0 as online at boot. However in practice, there are systems which have node 0 as memoryless and cpuless. This can cause 1. numa_balancing to be enabled on systems with only one online node. 2. Existence of dummy (cpuless and memoryless) node which can confuse users/scripts looking at output of lscpu / numactl. This patchset wants to correct this anomaly. This should only affect systems that have CONFIG_MEMORYLESS_NODES. Currently there are only 2 architectures ia64 and powerpc that have this config. Note: Patch 3 in this patch series depends on patches 1 and 2. Without patches 1 and 2, patch 3 might crash powerpc. v5.7-rc3 available: 2 nodes (0,2) node 0 cpus: node 0 size: 0 MB node 0 free: 0 MB node 2 cpus: 0 1 2 3 4 5 6 7 node 2 size: 32625 MB node 2 free: 31490 MB node distances: node 0 2 0: 10 20 2: 20 10 proc and sys files ------------------ /sys/devices/system/node/online: 0,2 /proc/sys/kernel/numa_balancing: 1 /sys/devices/system/node/has_cpu: 2 /sys/devices/system/node/has_memory: 2 /sys/devices/system/node/has_normal_memory: 2 /sys/devices/system/node/possible: 0-31 v5.7-rc3 + patches ------------------ available: 1 nodes (2) node 2 cpus: 0 1 2 3 4 5 6 7 node 2 size: 32625 MB node 2 free: 31487 MB node distances: node 2 2: 10 proc and sys files ------------------ /sys/devices/system/node/online: 2 /proc/sys/kernel/numa_balancing: 0 /sys/devices/system/node/has_cpu: 2 /sys/devices/system/node/has_memory: 2 /sys/devices/system/node/has_normal_memory: 2 /sys/devices/system/node/possible: 0-31 Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Cc: Michal Hocko Cc: Mel Gorman Cc: Vlastimil Babka Cc: "Kirill A. Shutemov" Cc: Christopher Lameter Cc: Michael Ellerman Cc: Andrew Morton Cc: Linus Torvalds Cc: Gautham R Shenoy Srikar Dronamraju (3): powerpc/numa: Set numa_node for all possible cpus powerpc/numa: Prefer node id queried from vphn mm/page_alloc: Keep memoryless cpuless node 0 offline arch/powerpc/mm/numa.c | 35 ++++++++++++++++++++++++----------- mm/page_alloc.c | 4 +++- 2 files changed, 27 insertions(+), 12 deletions(-) -- 2.20.1