Re: [PATCH v3 00/12] memory-hotplug: hot-remove physical memory

Wen Congyang
2012-11-16T11:49:23Z

Ping

At 11/01/2012 05:44 PM, Wen Congyang Wrote:
> The patch-set was divided from following thread's patch-set.
> https://lkml.org/lkml/2012/9/5/201
>
> The last version of this patchset:
> https://lkml.org/lkml/2012/10/23/213
>
> If you want to know the reason, please read following thread.
>
> https://lkml.org/lkml/2012/10/2/83
>
> The patch-set has only the function of kernel core side for physical
> memory hot remove. So if you use the patch, please apply following
> patches.
>
> - bug fix for memory hot remove
> https://lkml.org/lkml/2012/10/31/269
>
> - acpi framework
> https://lkml.org/lkml/2012/10/26/175
>
> The patches can free/remove the following things:
>
> - /sys/firmware/memmap/X/{end, start, type} : [PATCH 2/10]
> - mem_section and related sysfs files : [PATCH 3-4/10]
> - memmap of sparse-vmemmap : [PATCH 5-7/10]
> - page table of removed memory : [RFC PATCH 8/10]
> - node and related sysfs files : [RFC PATCH 9-10/10]
>
> * [PATCH 2/10] checks whether the memory can be removed or not.
>
> 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
> 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. 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
>
>
> Changelogs from v2 to v3:
> Patch9: call sync_global_pgds() if pgd is changed
> Patch10: fix a problem int the patch
>
> Changelogs from v1 to v2:
> Patch1: new patch, offline memory twice. 1st iterate: offline every non primary
> memory block. 2nd iterate: offline primary (i.e. first added) memory
> block.
>
> Patch3: new patch, no logical change, just remove reduntant codes.
>
> Patch9: merge the patch from wujianguo into this patch. flush tlb on all cpu
> after the pagetable is changed.
>
> Patch12: new patch, free node_data when a node is offlined
>
> Wen Congyang (6):
> memory-hotplug: try to offline the memory twice to avoid dependence
> memory-hotplug: remove redundant codes
> memory-hotplug: introduce new function arch_remove_memory() for
> removing page table depends on architecture
> memory-hotplug: remove page table of x86_64 architecture
> memory-hotplug: remove sysfs file of node
> memory-hotplug: free node_data when a node is offlined
>
> Yasuaki Ishimatsu (6):
> memory-hotplug: check whether all memory blocks are offlined or not
> when removing memory
> memory-hotplug: remove /sys/firmware/memmap/X sysfs
> memory-hotplug: unregister memory section on SPARSEMEM_VMEMMAP
> memory-hotplug: implement register_page_bootmem_info_section of
> sparse-vmemmap
> memory-hotplug: remove memmap of sparse-vmemmap
> memory-hotplug: memory_hotplug: clear zone when removing the memory
>
> arch/ia64/mm/discontig.c | 14 ++
> arch/ia64/mm/init.c | 18 ++
> arch/powerpc/mm/init_64.c | 14 ++
> arch/powerpc/mm/mem.c | 12 +
> arch/s390/mm/init.c | 12 +
> arch/s390/mm/vmem.c | 14 ++
> arch/sh/mm/init.c | 17 ++
> 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 | 12 +
> arch/x86/mm/init_64.c | 417 +++++++++++++++++++++++++++++++++++
> arch/x86/mm/pageattr.c | 47 ++--
> drivers/acpi/acpi_memhotplug.c | 8 +-
> drivers/base/memory.c | 6 +
> drivers/firmware/memmap.c | 98 +++++++-
> include/linux/firmware-map.h | 6 +
> include/linux/memory_hotplug.h | 15 +-
> include/linux/mm.h | 5 +-
> mm/memory_hotplug.c | 409 ++++++++++++++++++++++++++++++++--
> mm/sparse.c | 5 +-
> 21 files changed, 1095 insertions(+), 57 deletions(-)
>