From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f199.google.com (mail-wr0-f199.google.com [209.85.128.199]) by kanga.kvack.org (Postfix) with ESMTP id ADADA6B0069 for ; Thu, 23 Nov 2017 11:03:01 -0500 (EST) Received: by mail-wr0-f199.google.com with SMTP id z14so7899271wrb.12 for ; Thu, 23 Nov 2017 08:03:01 -0800 (PST) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id 59si2126382edf.265.2017.11.23.08.03.00 for (version=TLS1 cipher=AES128-SHA bits=128/128); Thu, 23 Nov 2017 08:03:00 -0800 (PST) Date: Thu, 23 Nov 2017 17:02:58 +0100 From: Michal Hocko Subject: Re: [PATCH v2 0/5] Memory hotplug support for arm64 - complete patchset v2 Message-ID: <20171123160258.xmw5lxnjfch2dxfw@dhcp22.suse.cz> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Andrea Reale Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, m.bielski@virtualopensystems.com, arunks@qti.qualcomm.com, mark.rutland@arm.com, scott.branden@broadcom.com, will.deacon@arm.com, qiuxishi@huawei.com, catalin.marinas@arm.com, realean2@ie.ibm.com On Thu 23-11-17 11:13:35, Andrea Reale wrote: > Hi all, Hi, > > this is a second round of patches to introduce memory hotplug and > hotremove support for arm64. It builds on the work previously published at > [1] and it implements the feedback received in the first round of reviews. > > The patchset applies and has been tested on commit bebc6082da0a ("Linux > 4.14"). > > Due to a small regression introduced with commit 8135d8926c08 > ("mm: memory_hotplug: memory hotremove supports thp migration"), you > will need to appy patch [2] first, until the fix is not upstreamed. > > Comments and feedback are gold. > > [1] https://lkml.org/lkml/2017/4/11/536 > [2] https://lkml.org/lkml/2017/11/20/902 I will try to have a look but I do not expect to understand any of arm64 specific changes so I will focus on the generic code but it would help a _lot_ if the cover letter provided some overview of what has been done from a higher level POV. What are the arch pieces and what is the generic code missing. A quick glance over patches suggests that changelogs for specific patches are modest as well. Could you give us more information please? Reviewing hundreds lines of code without context is a pain. > Changes v1->v2: > - swapper pgtable updated in place on hot add, avoiding unnecessary copy > - stop_machine used to updated swapper on hot add, avoiding races > - introduced check on offlining state before hot remove > - new memblock flag used to mark partially unused vmemmap pages, avoiding > the nasty 0xFD hack used in the prev rev (and in x86 hot remove code) > - proper cleaning sequence for p[um]ds,ptes and related TLB management > - Removed macros that changed hot remove behavior based on number > of pgtable levels. Now this is hidden in the pgtable traversal macros. > - Check on the corner case where P[UM]Ds would have to be split during > hot remove: now this is forbidden. > - Minor fixes and refactoring. > > Andrea Reale (4): > mm: memory_hotplug: Remove assumption on memory state before hotremove > mm: memory_hotplug: memblock to track partially removed vmemmap mem > mm: memory_hotplug: Add memory hotremove probe device > mm: memory-hotplug: Add memory hot remove support for arm64 > > Maciej Bielski (1): > mm: memory_hotplug: Memory hotplug (add) support for arm64 > > arch/arm64/Kconfig | 15 + > arch/arm64/configs/defconfig | 2 + > arch/arm64/include/asm/mmu.h | 7 + > arch/arm64/mm/init.c | 116 ++++++++ > arch/arm64/mm/mmu.c | 609 ++++++++++++++++++++++++++++++++++++++++- > drivers/acpi/acpi_memhotplug.c | 2 +- > drivers/base/memory.c | 34 ++- > include/linux/memblock.h | 12 + > include/linux/memory_hotplug.h | 9 +- > mm/memblock.c | 32 +++ > mm/memory_hotplug.c | 13 +- > 11 files changed, 835 insertions(+), 16 deletions(-) > > -- > 2.7.4 > -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org