[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <4FFCE3E6.709@cn.fujitsu.com>
Date: Wed, 11 Jul 2012 10:24:38 +0800
From: Wen Congyang <wency@...fujitsu.com>
To: Yasuaki Ishimatsu <isimatu.yasuaki@...fujitsu.com>
CC: linux-mm@...ck.org, linux-kernel@...r.kernel.org,
linuxppc-dev@...ts.ozlabs.org, linux-acpi@...r.kernel.org,
rientjes@...gle.com, liuj97@...il.com, len.brown@...el.com,
benh@...nel.crashing.org, paulus@...ba.org, cl@...ux.com,
minchan.kim@...il.com, akpm@...ux-foundation.org,
kosaki.motohiro@...fujitsu.com
Subject: Re: [RFC PATCH v3 0/13] memory-hotplug : hot-remove physical memory
At 07/11/2012 09:52 AM, Wen Congyang Wrote:
> At 07/09/2012 06:21 PM, Yasuaki Ishimatsu Wrote:
>> This patch series aims to support physical memory hot-remove.
>>
>> [RFC PATCH v3 1/13] memory-hotplug : rename remove_memory to offline_memory
>> [RFC PATCH v3 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove
>> [RFC PATCH v3 3/13] memory-hotplug : unify argument of firmware_map_add_early/hotplug
>> [RFC PATCH v3 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs
>> [RFC PATCH v3 5/13] memory-hotplug : does not release memory region in PAGES_PER_SECTION chunks
>> [RFC PATCH v3 6/13] memory-hotplug : add memory_block_release
>> [RFC PATCH v3 7/13] memory-hotplug : remove_memory calls __remove_pages
>> [RFC PATCH v3 8/13] memory-hotplug : check page type in get_page_bootmem
>> [RFC PATCH v3 9/13] memory-hotplug : move register_page_bootmem_info_node and put_page_bootmem for
>> sparse-vmemmap
>> [RFC PATCH v3 10/13] memory-hotplug : implement register_page_bootmem_info_section of sparse-vmemmap
>> [RFC PATCH v3 11/13] memory-hotplug : free memmap of sparse-vmemmap
>> [RFC PATCH v3 12/13] memory-hotplug : add node_device_release
>> [RFC PATCH v3 13/13] memory-hotplug : remove sysfs file of node
>>
>> Even if you apply these patches, you cannot remove the physical memory
>> completely since these patches are still under development. I want you to
>> cooperate to improve the physical memory hot-remove. So please review these
>> patches and give your comment/idea.
>>
>> The patches can free/remove following things:
>>
>> - acpi_memory_info : [RFC PATCH 2/13]
>> - /sys/firmware/memmap/X/{end, start, type} : [RFC PATCH 4/13]
>> - iomem_resource : [RFC PATCH 5/13]
>> - mem_section and related sysfs files : [RFC PATCH 6-11/13]
>> - node and related sysfs files : [RFC PATCH 12-13/13]
>>
>> The patches cannot do following things yet:
>>
>> - page table of removed memory
>>
>> If you find lack of function for physical memory hot-remove, please let me
>> know.
>>
>> 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
>
> acpi_memory_device_remove() will be called not only when we write
> 1 to /sys/bus/acpi/devices/PNP0C80:XX/eject. When we unbind it
> from the driver or remove the module acpi_memhotplug, this function
> will be called too.
>
> I will check whether your patch can work for these two cases.
I have checked it, and I think your patch can not work for these 2 cases.
When we unbind the device from the driver(write device name to
/sys/bus/acpi/drivers/acpi_memhotplug/unbind), driver_unbind()
will be called. This function does not care the return value.
When we remove the module acpi_memhotplug, acpi_memory_device_exit()
will be called. This function does not care the return value too.
I don't know whether there are some other cases that acpi_memory_device_remove()
will be called.
Thanks
Wen Congyang
>
> Thanks
> Wen Congyang
>
>>
>> [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()
>>
>> ---
>> arch/powerpc/platforms/pseries/hotplug-memory.c | 16 +-
>> arch/x86/mm/init_64.c | 144 ++++++++++++++++++++++++
>> drivers/acpi/acpi_memhotplug.c | 28 ++++
>> drivers/base/memory.c | 54 ++++++++-
>> drivers/base/node.c | 7 +
>> drivers/firmware/memmap.c | 78 ++++++++++++-
>> include/linux/firmware-map.h | 6 +
>> include/linux/memory.h | 5
>> include/linux/memory_hotplug.h | 17 --
>> include/linux/mm.h | 5
>> mm/memory_hotplug.c | 98 ++++++++++++----
>> mm/sparse.c | 5
>> 12 files changed, 414 insertions(+), 49 deletions(-)
>>
>>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists