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=-3.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 11F19C2BA80 for ; Tue, 7 Apr 2020 03:07:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id B0E0F218AC for ; Tue, 7 Apr 2020 03:07:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="dZEmCNrt" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B0E0F218AC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 5E8108E004B; Mon, 6 Apr 2020 23:07:47 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 571888E0001; Mon, 6 Apr 2020 23:07:47 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4866E8E004B; Mon, 6 Apr 2020 23:07:47 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0142.hostedemail.com [216.40.44.142]) by kanga.kvack.org (Postfix) with ESMTP id 2C4688E0001 for ; Mon, 6 Apr 2020 23:07:47 -0400 (EDT) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id F08AD180AD806 for ; Tue, 7 Apr 2020 03:07:46 +0000 (UTC) X-FDA: 76679574132.07.shirt27_7e1d1407f455b X-HE-Tag: shirt27_7e1d1407f455b X-Filterd-Recvd-Size: 6169 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf25.hostedemail.com (Postfix) with ESMTP for ; Tue, 7 Apr 2020 03:07:46 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id DD35A217D8; Tue, 7 Apr 2020 03:07:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586228865; bh=gLO7DR0n7aDF8udz2uElh+XvuIpTSVxiWlgoiOvF0xY=; h=Date:From:To:Subject:In-Reply-To:From; b=dZEmCNrtJ0TADt2kuZJG0q06qLQ95QA5ZANQPV9Te3poZeLDFflYZJmFdPMgtmKht Oh89KB+mEoY/hcTLoiMj/iZ4MJ9jEN42xHhL/yqE14Oz9557TAkl2FNtoX7ydcHxAY MjLCg0EexZzULFAItjVwbDQIeZIALsECNXeiTsV0= Date: Mon, 06 Apr 2020 20:07:44 -0700 From: Andrew Morton To: akpm@linux-foundation.org, benh@kernel.crashing.org, bhe@redhat.com, david@redhat.com, ehabkost@redhat.com, gregkh@linuxfoundation.org, haiyangz@microsoft.com, imammedo@redhat.com, kys@microsoft.com, linux-mm@kvack.org, mhocko@suse.com, mm-commits@vger.kernel.org, mpe@ellerman.id.au, osalvador@suse.de, pankaj.gupta.linux@gmail.com, paulus@samba.org, rafael@kernel.org, richard.weiyang@gmail.com, sthemmin@microsoft.com, torvalds@linux-foundation.org, vkuznets@redhat.com, wei.liu@kernel.org, yuhuang@redhat.com Subject: [patch 070/166] mm/memory_hotplug: allow to specify a default online_type Message-ID: <20200407030744.rxeMK84Sk%akpm@linux-foundation.org> In-Reply-To: <20200406200254.a69ebd9e08c4074e41ddebaf@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: David Hildenbrand Subject: mm/memory_hotplug: allow to specify a default online_type For now, distributions implement advanced udev rules to essentially - Don't online any hotplugged memory (s390x) - Online all memory to ZONE_NORMAL (e.g., most virt environments like hyperv) - Online all memory to ZONE_MOVABLE in case the zone imbalance is taken care of (e.g., bare metal, special virt environments) In summary: All memory is usually onlined the same way, however, the kernel always has to ask user space to come up with the same answer. E.g., Hyper-V always waits for a memory block to get onlined before continuing, otherwise it might end up adding memory faster than onlining it, which can result in strange OOM situations. This waiting slows down adding of a bigger amount of memory. Let's allow to specify a default online_type, not just "online" and "offline". This allows distributions to configure the default online_type when booting up and be done with it. We can now specify "offline", "online", "online_movable" and "online_kernel" via - "memhp_default_state=" on the kernel cmdline - /sys/devices/system/memory/auto_online_blocks just like we are able to specify for a single memory block via /sys/devices/system/memory/memoryX/state Link: http://lkml.kernel.org/r/20200317104942.11178-9-david@redhat.com Signed-off-by: David Hildenbrand Reviewed-by: Wei Yang Acked-by: Michal Hocko Reviewed-by: Baoquan He Acked-by: Pankaj Gupta Cc: Greg Kroah-Hartman Cc: Oscar Salvador Cc: "Rafael J. Wysocki" Cc: Wei Yang Cc: Benjamin Herrenschmidt Cc: Eduardo Habkost Cc: Haiyang Zhang Cc: Igor Mammedov Cc: "K. Y. Srinivasan" Cc: Michael Ellerman Cc: Paul Mackerras Cc: Stephen Hemminger Cc: Vitaly Kuznetsov Cc: Wei Liu Cc: Yumei Huang Signed-off-by: Andrew Morton --- drivers/base/memory.c | 11 +++++------ include/linux/memory_hotplug.h | 2 ++ mm/memory_hotplug.c | 8 ++++---- 3 files changed, 11 insertions(+), 10 deletions(-) --- a/drivers/base/memory.c~mm-memory_hotplug-allow-to-specify-a-default-online_type +++ a/drivers/base/memory.c @@ -34,7 +34,7 @@ static const char *const online_type_to_ [MMOP_ONLINE_MOVABLE] = "online_movable", }; -static int memhp_online_type_from_str(const char *str) +int memhp_online_type_from_str(const char *str) { int i; @@ -386,13 +386,12 @@ static ssize_t auto_online_blocks_store( struct device_attribute *attr, const char *buf, size_t count) { - if (sysfs_streq(buf, "online")) - memhp_default_online_type = MMOP_ONLINE; - else if (sysfs_streq(buf, "offline")) - memhp_default_online_type = MMOP_OFFLINE; - else + const int online_type = memhp_online_type_from_str(buf); + + if (online_type < 0) return -EINVAL; + memhp_default_online_type = online_type; return count; } --- a/include/linux/memory_hotplug.h~mm-memory_hotplug-allow-to-specify-a-default-online_type +++ a/include/linux/memory_hotplug.h @@ -117,6 +117,8 @@ extern int arch_add_memory(int nid, u64 struct mhp_restrictions *restrictions); extern u64 max_mem_size; +extern int memhp_online_type_from_str(const char *str); + /* Default online_type (MMOP_*) when new memory blocks are added. */ extern int memhp_default_online_type; /* If movable_node boot option specified */ --- a/mm/memory_hotplug.c~mm-memory_hotplug-allow-to-specify-a-default-online_type +++ a/mm/memory_hotplug.c @@ -74,10 +74,10 @@ int memhp_default_online_type = MMOP_ONL static int __init setup_memhp_default_state(char *str) { - if (!strcmp(str, "online")) - memhp_default_online_type = MMOP_ONLINE; - else if (!strcmp(str, "offline")) - memhp_default_online_type = MMOP_OFFLINE; + const int online_type = memhp_online_type_from_str(str); + + if (online_type >= 0) + memhp_default_online_type = online_type; return 1; } _