Messages in this thread | | | Date | Sat, 29 Sep 2012 16:19:38 +0800 | From | Ni zhan Chen <> | Subject | Re: [RFC v9 PATCH 00/21] memory-hotplug: hot-remove physical memory |
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On 09/05/2012 05:25 PM, wency@cn.fujitsu.com wrote: > From: Wen Congyang <wency@cn.fujitsu.com> > > This patch series aims to support physical memory hot-remove. > > The patches can free/remove the following things: > > - acpi_memory_info : [RFC PATCH 4/19] > - /sys/firmware/memmap/X/{end, start, type} : [RFC PATCH 8/19] > - iomem_resource : [RFC PATCH 9/19] > - mem_section and related sysfs files : [RFC PATCH 10-11, 13-16/19] > - page table of removed memory : [RFC PATCH 12/19] > - node and related sysfs files : [RFC PATCH 18-19/19] > > If you find lack of function for physical memory hot-remove, please let me > know. > > How to test this patchset? > 1. apply this patchset and build the kernel. MEMORY_HOTPLUG, MEMORY_HOTREMOVE, > ACPI_HOTPLUG_MEMORY must be selected. > 2. load the module acpi_memhotplug
Hi Yasuaki,
where is the acpi_memhotplug module?
> 3. hotplug the memory device(it depends on your hardware) > You will see the memory device under the directory /sys/bus/acpi/devices/. > Its name is PNP0C80:XX. > 4. online/offline pages provided by this memory device > You can write online/offline to /sys/devices/system/memory/memoryX/state to > online/offline pages provided by this memory device > 5. hotremove the memory device > You can hotremove the memory device by the hardware, or writing 1 to > /sys/bus/acpi/devices/PNP0C80:XX/eject. > > Note: if the memory provided by the memory device is used by the kernel, it > can't be offlined. It is not a bug. > > Known problems: > 1. memory can't be offlined when CONFIG_MEMCG is selected. > For example: there is a memory device on node 1. The address range > is [1G, 1.5G). You will find 4 new directories memory8, memory9, memory10, > and memory11 under the directory /sys/devices/system/memory/. > If CONFIG_MEMCG is selected, we will allocate memory to store page cgroup > when we online pages. When we online memory8, the memory stored page cgroup > is not provided by this memory device. But when we online memory9, the memory > stored page cgroup may be provided by memory8. So we can't offline memory8 > now. We should offline the memory in the reversed order. > When the memory device is hotremoved, we will auto offline memory provided > by this memory device. But we don't know which memory is onlined first, so > offlining memory may fail. In such case, you should offline the memory by > hand before hotremoving the memory device. > 2. hotremoving memory device may cause kernel panicked > This bug will be fixed by Liu Jiang's patch: > https://lkml.org/lkml/2012/7/3/1 > > change log of v9: > [RFC PATCH v9 8/21] > * add a lock to protect the list map_entries > * add an indicator to firmware_map_entry to remember whether the memory > is allocated from bootmem > [RFC PATCH v9 10/21] > * change the macro to inline function > [RFC PATCH v9 19/21] > * don't offline the node if the cpu on the node is onlined > [RFC PATCH v9 21/21] > * create new patch: auto offline page_cgroup when onlining memory block > failed > > change log of v8: > [RFC PATCH v8 17/20] > * Fix problems when one node's range include the other nodes > [RFC PATCH v8 18/20] > * fix building error when CONFIG_MEMORY_HOTPLUG_SPARSE or CONFIG_HUGETLBFS > is not defined. > [RFC PATCH v8 19/20] > * don't offline node when some memory sections are not removed > [RFC PATCH v8 20/20] > * create new patch: clear hwpoisoned flag when onlining pages > > change log of v7: > [RFC PATCH v7 4/19] > * do not continue if acpi_memory_device_remove_memory() fails. > [RFC PATCH v7 15/19] > * handle usemap in register_page_bootmem_info_section() too. > > change log of v6: > [RFC PATCH v6 12/19] > * fix building error on other archtitectures than x86 > > [RFC PATCH v6 15-16/19] > * fix building error on other archtitectures than x86 > > change log of v5: > * merge the patchset to clear page table and the patchset to hot remove > memory(from ishimatsu) to one big patchset. > > [RFC PATCH v5 1/19] > * rename remove_memory() to offline_memory()/offline_pages() > > [RFC PATCH v5 2/19] > * new patch: implement offline_memory(). This function offlines pages, > update memory block's state, and notify the userspace that the memory > block's state is changed. > > [RFC PATCH v5 4/19] > * offline and remove memory in acpi_memory_disable_device() too. > > [RFC PATCH v5 17/19] > * new patch: add a new function __remove_zone() to revert the things done > in the function __add_zone(). > > [RFC PATCH v5 18/19] > * flush work befor reseting node device. > > change log of v4: > * remove "memory-hotplug : unify argument of firmware_map_add_early/hotplug" > from the patch series, since the patch is a bugfix. It is being disccussed > on other thread. But for testing the patch series, the patch is needed. > So I added the patch as [PATCH 0/13]. > > [RFC PATCH v4 2/13] > * check memory is online or not at remove_memory() > * add memory_add_physaddr_to_nid() to acpi_memory_device_remove() for > getting node id > > [RFC PATCH v4 3/13] > * create new patch : check memory is online or not at online_pages() > > [RFC PATCH v4 4/13] > * add __ref section to remove_memory() > * call firmware_map_remove_entry() before remove_sysfs_fw_map_entry() > > [RFC PATCH v4 11/13] > * rewrite register_page_bootmem_memmap() for removing page used as PT/PMD > > change log of v3: > * rebase to 3.5.0-rc6 > > [RFC PATCH v2 2/13] > * remove extra kobject_put() > > * The patch was commented by Wen. Wen's comment is > "acpi_memory_device_remove() should ignore a return value of > remove_memory() since caller does not care the return value". > But I did not change it since I think caller should care the > return value. And I am trying to fix it as follow: > > https://lkml.org/lkml/2012/7/5/624 > > [RFC PATCH v2 4/13] > * remove a firmware_memmap_entry allocated by kzmalloc() > > change log of v2: > [RFC PATCH v2 2/13] > * check whether memory block is offline or not before calling offline_memory() > * check whether section is valid or not in is_memblk_offline() > * call kobject_put() for each memory_block in is_memblk_offline() > > [RFC PATCH v2 3/13] > * unify the end argument of firmware_map_add_early/hotplug > > [RFC PATCH v2 4/13] > * add release_firmware_map_entry() for freeing firmware_map_entry > > [RFC PATCH v2 6/13] > * add release_memory_block() for freeing memory_block > > [RFC PATCH v2 11/13] > * fix wrong arguments of free_pages() > > > Wen Congyang (8): > memory-hotplug: implement offline_memory() > memory-hotplug: store the node id in acpi_memory_device > memory-hotplug: export the function acpi_bus_remove() > memory-hotplug: call acpi_bus_remove() to remove memory device > memory-hotplug: introduce new function arch_remove_memory() > memory-hotplug: remove sysfs file of node > memory-hotplug: clear hwpoisoned flag when onlining pages > memory-hotplug: auto offline page_cgroup when onlining memory block > failed > > Yasuaki Ishimatsu (13): > memory-hotplug: rename remove_memory() to > offline_memory()/offline_pages() > memory-hotplug: offline and remove memory when removing the memory > device > memory-hotplug: check whether memory is present or not > memory-hotplug: remove /sys/firmware/memmap/X sysfs > memory-hotplug: does not release memory region in PAGES_PER_SECTION > chunks > memory-hotplug: add memory_block_release > memory-hotplug: remove_memory calls __remove_pages > memory-hotplug: check page type in get_page_bootmem > memory-hotplug: move register_page_bootmem_info_node and > put_page_bootmem for sparse-vmemmap > memory-hotplug: implement register_page_bootmem_info_section of > sparse-vmemmap > memory-hotplug: free memmap of sparse-vmemmap > memory_hotplug: clear zone when the memory is removed > memory-hotplug: add node_device_release > > arch/ia64/mm/discontig.c | 14 + > arch/ia64/mm/init.c | 16 + > arch/powerpc/mm/init_64.c | 14 + > arch/powerpc/mm/mem.c | 14 + > arch/powerpc/platforms/pseries/hotplug-memory.c | 16 +- > arch/s390/mm/init.c | 12 + > arch/s390/mm/vmem.c | 14 + > arch/sh/mm/init.c | 15 + > arch/sparc/mm/init_64.c | 14 + > arch/tile/mm/init.c | 8 + > arch/x86/include/asm/pgtable_types.h | 1 + > arch/x86/mm/init_32.c | 10 + > arch/x86/mm/init_64.c | 331 ++++++++++++++++++ > arch/x86/mm/pageattr.c | 47 ++-- > drivers/acpi/acpi_memhotplug.c | 54 +++- > drivers/acpi/scan.c | 3 +- > drivers/base/memory.c | 88 ++++- > drivers/base/node.c | 11 + > drivers/firmware/memmap.c | 98 +++++- > include/acpi/acpi_bus.h | 1 + > include/linux/firmware-map.h | 6 + > include/linux/memory.h | 5 + > include/linux/memory_hotplug.h | 25 +- > include/linux/mm.h | 5 +- > include/linux/mmzone.h | 19 + > mm/memory_hotplug.c | 424 +++++++++++++++++++++-- > mm/page_cgroup.c | 3 + > mm/sparse.c | 5 +- > 28 files changed, 1181 insertions(+), 92 deletions(-) > > -- > 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: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> >
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