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=-8.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 F3528C2BB1D for ; Tue, 17 Mar 2020 10:50:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BEA7A20719 for ; Tue, 17 Mar 2020 10:50:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="SgiBExM0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726016AbgCQKuA (ORCPT ); Tue, 17 Mar 2020 06:50:00 -0400 Received: from us-smtp-delivery-74.mimecast.com ([63.128.21.74]:47456 "EHLO us-smtp-delivery-74.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725794AbgCQKuA (ORCPT ); Tue, 17 Mar 2020 06:50:00 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1584442198; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=88OsB2jSDoNgzvIn7pkzvFuton0cXl1y6ameX4o2p6g=; b=SgiBExM0EVsMXqawwa7B8nG/tRJXIoiGk+pyaNEC7LxhD9V9XsYdIQ5C5fFWic/c3USmyV rzd5GDwX4OtVWkuLlZirNklrfvcHkRvxVPBm8d5buEx/UxliZ2V5e0yNH80NAP3xU3Nq38 dbmC4/Ws+dzRyfGP3zSqbZX0gadt+Z8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-364-zxSchhQfP1mBFTtHlQC6rw-1; Tue, 17 Mar 2020 06:49:54 -0400 X-MC-Unique: zxSchhQfP1mBFTtHlQC6rw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A3F511005514; Tue, 17 Mar 2020 10:49:51 +0000 (UTC) Received: from t480s.redhat.com (ovpn-112-136.ams2.redhat.com [10.36.112.136]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2A28273865; Tue, 17 Mar 2020 10:49:42 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, linux-hyperv@vger.kernel.org, David Hildenbrand , Vitaly Kuznetsov , Yumei Huang , Igor Mammedov , Baoquan He , Eduardo Habkost , Milan Zamazal , Andrew Morton , Benjamin Herrenschmidt , Greg Kroah-Hartman , Haiyang Zhang , "K. Y. Srinivasan" , Michael Ellerman , Michal Hocko , Michal Hocko , Oscar Salvador , Paul Mackerras , "Rafael J. Wysocki" , Stephen Hemminger , Wei Liu , Wei Yang Subject: [PATCH v2 0/8] mm/memory_hotplug: allow to specify a default online_type Date: Tue, 17 Mar 2020 11:49:34 +0100 Message-Id: <20200317104942.11178-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Content-Transfer-Encoding: quoted-printable Sender: linux-hyperv-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org Distributions nowadays use udev rules ([1] [2]) to specify if and how to online hotplugged memory. The rules seem to get more complex with many special cases. Due to the various special cases, CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE cannot be used. All memory hotplug is handled via udev rules. Everytime we hotplug memory, the udev rule will come to the same conclusion. Especially Hyper-V (but also soon virtio-mem) add a lot of memory in separate memory blocks and wait for memory to get onlined by us= er space before continuing to add more memory blocks (to not add memory fast= er than it is getting onlined). This of course slows down the whole memory hotplug process. To make the job of distributions easier and to avoid udev rules that get more and more complicated, let's extend the mechanism provided by - /sys/devices/system/memory/auto_online_blocks - "memhp_default_state=3D" on the kernel cmdline to be able to specify also "online_movable" as well as "online_kernel" v1 -> v2: - Tweaked some patch descriptions - Added -- "powernv/memtrace: always online added memory blocks" -- "hv_balloon: don't check for memhp_auto_online manually" -- "mm/memory_hotplug: unexport memhp_auto_online" - "mm/memory_hotplug: convert memhp_auto_online to store an online_type" -- No longer touches hv/memtrace code =3D=3D=3D Example /usr/libexec/config-memhotplug =3D=3D=3D #!/bin/bash VIRT=3D`systemd-detect-virt --vm` ARCH=3D`uname -p` sense_virtio_mem() { if [ -d "/sys/bus/virtio/drivers/virtio_mem/" ]; then DEVICES=3D`find /sys/bus/virtio/drivers/virtio_mem/ -maxdepth 1 -type= l | wc -l` if [ $DEVICES !=3D "0" ]; then return 0 fi fi return 1 } if [ ! -e "/sys/devices/system/memory/auto_online_blocks" ]; then echo "Memory hotplug configuration support missing in the kernel" exit 1 fi if grep "memhp_default_state=3D" /proc/cmdline > /dev/null; then echo "Memory hotplug configuration overridden in kernel cmdline (memhp_= default_state=3D)" exit 1 fi if [ $VIRT =3D=3D "microsoft" ]; then echo "Detected Hyper-V on $ARCH" # Hyper-V wants all memory in ZONE_NORMAL ONLINE_TYPE=3D"online_kernel" elif sense_virtio_mem; then echo "Detected virtio-mem on $ARCH" # virtio-mem wants all memory in ZONE_NORMAL ONLINE_TYPE=3D"online_kernel" elif [ $ARCH =3D=3D "s390x" ] || [ $ARCH =3D=3D "s390" ]; then echo "Detected $ARCH" # standby memory should not be onlined automatically ONLINE_TYPE=3D"offline" elif [ $ARCH =3D=3D "ppc64" ] || [ $ARCH =3D=3D "ppc64le" ]; then echo "Detected" $ARCH # PPC64 onlines all hotplugged memory right from the kernel ONLINE_TYPE=3D"offline" elif [ $VIRT =3D=3D "none" ]; then echo "Detected bare-metal on $ARCH" # Bare metal users expect hotplugged memory to be unpluggable. We assum= e # that ZONE imbalances on such enterpise servers cannot happen and is # properly documented ONLINE_TYPE=3D"online_movable" else # TODO: Hypervisors that want to unplug DIMMs and can guarantee that ZO= NE # imbalances won't happen echo "Detected $VIRT on $ARCH" # Usually, ballooning is used in virtual environments, so memory should= go to # ZONE_NORMAL. However, sometimes "movable_node" is relevant. ONLINE_TYPE=3D"online" fi echo "Selected online_type:" $ONLINE_TYPE # Configure what to do with memory that will be hotplugged in the future echo $ONLINE_TYPE 2>/dev/null > /sys/devices/system/memory/auto_online_bl= ocks if [ $? !=3D "0" ]; then echo "Memory hotplug cannot be configured (e.g., old kernel or missing = permissions)" # A backup udev rule should handle old kernels if necessary exit 1 fi # Process all already pluggedd blocks (e.g., DIMMs, but also Hyper-V or v= irtio-mem) if [ $ONLINE_TYPE !=3D "offline" ]; then for MEMORY in /sys/devices/system/memory/memory*; do STATE=3D`cat $MEMORY/state` if [ $STATE =3D=3D "offline" ]; then echo $ONLINE_TYPE > $MEMORY/state fi done fi =3D=3D=3D Example /usr/lib/systemd/system/config-memhotplug.service =3D=3D= =3D [Unit] Description=3DConfigure memory hotplug behavior DefaultDependencies=3Dno Conflicts=3Dshutdown.target Before=3Dsysinit.target shutdown.target After=3Dsystemd-modules-load.service ConditionPathExists=3D|/sys/devices/system/memory/auto_online_blocks [Service] ExecStart=3D/usr/libexec/config-memhotplug Type=3Doneshot TimeoutSec=3D0 RemainAfterExit=3Dyes [Install] WantedBy=3Dsysinit.target =3D=3D=3D Example modification to the 40-redhat.rules [2] =3D=3D=3D diff --git a/40-redhat.rules b/40-redhat.rules-new index 2c690e5..168fd03 100644 --- a/40-redhat.rules +++ b/40-redhat.rules-new @@ -6,6 +6,9 @@ SUBSYSTEM=3D=3D"cpu", ACTION=3D=3D"add", TEST=3D=3D"onlin= e", ATTR{online}=3D=3D"0", ATTR{online} # Memory hotadd request SUBSYSTEM!=3D"memory", GOTO=3D"memory_hotplug_end" ACTION!=3D"add", GOTO=3D"memory_hotplug_end" +# memory hotplug behavior configured +PROGRAM=3D=3D"grep online /sys/devices/system/memory/auto_online_blocks"= , GOTO=3D"memory_hotplug_end" + PROGRAM=3D"/bin/uname -p", RESULT=3D=3D"s390*", GOTO=3D"memory_hotplug_e= nd" ENV{.state}=3D"online" =3D=3D=3D [1] https://github.com/lnykryn/systemd-rhel/pull/281 [2] https://github.com/lnykryn/systemd-rhel/blob/staging/rules/40-redhat.= rules Cc: Vitaly Kuznetsov Cc: Yumei Huang Cc: Igor Mammedov Cc: Baoquan He Cc: Eduardo Habkost Cc: Milan Zamazal David Hildenbrand (8): drivers/base/memory: rename MMOP_ONLINE_KEEP to MMOP_ONLINE drivers/base/memory: map MMOP_OFFLINE to 0 drivers/base/memory: store mapping between MMOP_* and string in an array powernv/memtrace: always online added memory blocks hv_balloon: don't check for memhp_auto_online manually mm/memory_hotplug: unexport memhp_auto_online mm/memory_hotplug: convert memhp_auto_online to store an online_type mm/memory_hotplug: allow to specify a default online_type arch/powerpc/platforms/powernv/memtrace.c | 14 ++--- drivers/base/memory.c | 71 ++++++++++++----------- drivers/hv/hv_balloon.c | 25 ++++---- include/linux/memory_hotplug.h | 13 ++++- mm/memory_hotplug.c | 16 ++--- 5 files changed, 69 insertions(+), 70 deletions(-) --=20 2.24.1