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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 C9940C2BC11 for ; Tue, 8 Sep 2020 20:10:44 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (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 5FC3B208FE for ; Tue, 8 Sep 2020 20:10:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="e7kL1KLP" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5FC3B208FE Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=virtualization-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id BB617203CA; Tue, 8 Sep 2020 20:10:43 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Fdu+9TinyJht; Tue, 8 Sep 2020 20:10:42 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by silver.osuosl.org (Postfix) with ESMTP id 4559620358; Tue, 8 Sep 2020 20:10:42 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 31FE6C0859; Tue, 8 Sep 2020 20:10:42 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 81DADC0051 for ; Tue, 8 Sep 2020 20:10:41 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 67A4D8562A for ; Tue, 8 Sep 2020 20:10:41 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id FsqpzKQZTGji for ; Tue, 8 Sep 2020 20:10:38 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by fraxinus.osuosl.org (Postfix) with ESMTPS id 9004F85623 for ; Tue, 8 Sep 2020 20:10:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599595837; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=c3EXsANyRQfNPWugjklxVXDT/m3en9wKUY4fM1Sf5tA=; b=e7kL1KLPTC0NcQ56BOvHfFkbQJPwH36+0DPCRvptTbit5NPXHvcA7IyAmlIo6SD1WAdjHZ N3SC+qGJLWZoecYsGAWt3Q+N3tLXb26/bs8lfm6rBZmRInvH1agGGIM0fSz9DgVPSpnQwU t3sHBFe+ct0OWZ8l1DzL7gWw40SOXs0= 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-7-5kkWOmFZP5m0Qe57B5e2tg-1; Tue, 08 Sep 2020 16:10:34 -0400 X-MC-Unique: 5kkWOmFZP5m0Qe57B5e2tg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id F25761074667; Tue, 8 Sep 2020 20:10:28 +0000 (UTC) Received: from t480s.redhat.com (ovpn-115-46.ams2.redhat.com [10.36.115.46]) by smtp.corp.redhat.com (Postfix) with ESMTP id 04EEC5D9E8; Tue, 8 Sep 2020 20:10:13 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Subject: [PATCH v2 0/7] mm/memory_hotplug: selective merging of system ram resources Date: Tue, 8 Sep 2020 22:10:05 +0200 Message-Id: <20200908201012.44168-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Cc: linux-hyperv@vger.kernel.org, Michal Hocko , Benjamin Herrenschmidt , Pingfan Liu , virtualization@lists.linux-foundation.org, linux-mm@kvack.org, Oliver O'Halloran , Dan Williams , linux-s390@vger.kernel.org, Wei Liu , Stefano Stabellini , Dave Jiang , Baoquan He , linux-nvdimm@lists.01.org, Jason Gunthorpe , Michael Ellerman , "Michael S. Tsirkin" , Ard Biesheuvel , linux-acpi@vger.kernel.org, Wei Yang , xen-devel@lists.xenproject.org, Anton Blanchard , Heiko Carstens , Len Brown , Nathan Lynch , Julien Grall , Kees Cook , Vasily Gorbik , Leonardo Bras , Haiyang Zhang , Stephen Hemminger , Boris Ostrovsky , Christian Borntraeger , Juergen Gross , Pankaj Gupta , "Rafael J. Wysocki" , Greg Kroah-Hartman , Libor Pechacek , Thomas Gleixner , Eric Biederman , Vishal Verma , Paul Mackerras , Andrew Morton , =?UTF-8?q?Roger=20Pau=20Monn=C3=A9?= X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" Some add_memory*() users add memory in small, contiguous memory blocks. Examples include virtio-mem, hyper-v balloon, and the XEN balloon. This can quickly result in a lot of memory resources, whereby the actual resource boundaries are not of interest (e.g., it might be relevant for DIMMs, exposed via /proc/iomem to user space). We really want to merge added resources in this scenario where possible. Resources are effectively stored in a list-based tree. Having a lot of resources not only wastes memory, it also makes traversing that tree more expensive, and makes /proc/iomem explode in size (e.g., requiring kexec-tools to manually merge resources when creating a kdump header. The current kexec-tools resource count limit does not allow for more than ~100GB of memory with a memory block size of 128MB on x86-64). Let's allow to selectively merge system ram resources by specifying a new flag for add_memory*(). Patch #5 contains a /proc/iomem example. Only tested with virtio-mem. v1 -> v2: - I had another look at v1 after vacation and didn't like it - it felt like a hack. So I want forward and added a proper flag to add_memory*(), and introduce a clean (non-racy) way to mark System RAM resources mergeable. - "kernel/resource: move and rename IORESOURCE_MEM_DRIVER_MANAGED" -- Clean that flag up, felt wrong in the PnP section - "mm/memory_hotplug: prepare passing flags to add_memory() and friends" -- Previously sent in other context - decided to keep Wei's ack - "mm/memory_hotplug: MEMHP_MERGE_RESOURCE to specify merging of System RAM resources" -- Cleaner approach to get the job done by using proper flags and only merging the single, specified resource - "virtio-mem: try to merge system ram resources" "xen/balloon: try to merge system ram resources" "hv_balloon: try to merge system ram resources" -- Use the new flag MEMHP_MERGE_RESOURCE, much cleaner RFC -> v1: - Switch from rather generic "merge_child_mem_resources()" where a resource name has to be specified to "merge_system_ram_resources(). - Smaller comment/documentation/patch description changes/fixes David Hildenbrand (7): kernel/resource: make release_mem_region_adjustable() never fail kernel/resource: move and rename IORESOURCE_MEM_DRIVER_MANAGED mm/memory_hotplug: prepare passing flags to add_memory() and friends mm/memory_hotplug: MEMHP_MERGE_RESOURCE to specify merging of System RAM resources virtio-mem: try to merge system ram resources xen/balloon: try to merge system ram resources hv_balloon: try to merge system ram resources arch/powerpc/platforms/powernv/memtrace.c | 2 +- .../platforms/pseries/hotplug-memory.c | 2 +- drivers/acpi/acpi_memhotplug.c | 2 +- drivers/base/memory.c | 2 +- drivers/dax/kmem.c | 2 +- drivers/hv/hv_balloon.c | 2 +- drivers/s390/char/sclp_cmd.c | 2 +- drivers/virtio/virtio_mem.c | 3 +- drivers/xen/balloon.c | 2 +- include/linux/ioport.h | 12 +- include/linux/memory_hotplug.h | 19 ++- kernel/kexec_file.c | 2 +- kernel/resource.c | 109 ++++++++++++++---- mm/memory_hotplug.c | 48 +++----- 14 files changed, 141 insertions(+), 68 deletions(-) -- 2.26.2 _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization