At 10/05/2012 05:31 AM, KOSAKI Motohiro Wrote:
> On Wed, Oct 3, 2012 at 6:02 AM, Yasuaki Ishimatsu
> <isimatu.yasu...@jp.fujitsu.com> wrote:
>> From: Yasuaki Ishimatsu <isimatu.yasu...@jp.fujitsu.com>
>>
>> add_memory() hot adds a physical memory. But remove_memory does not
>> hot remove a phsical memory. It only offlines memory. The name
>> confuse us.
>>
>> So the patch renames remove_memory() to offline_memory(). We will
>> use rename_memory() for hot removing memory.
>>
>> CC: David Rientjes <rient...@google.com>
>> CC: Jiang Liu <liu...@gmail.com>
>> CC: Len Brown <len.br...@intel.com>
>> CC: Christoph Lameter <c...@linux.com>
>> Cc: Minchan Kim <minchan....@gmail.com>
>> CC: Andrew Morton <a...@linux-foundation.org>
>> CC: KOSAKI Motohiro <kosaki.motoh...@jp.fujitsu.com>
>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasu...@jp.fujitsu.com>
>> Signed-off-by: Wen Congyang <we...@cn.fujitsu.com>
>> ---
>>  drivers/acpi/acpi_memhotplug.c |    2 +-
>>  include/linux/memory_hotplug.h |    2 +-
>>  mm/memory_hotplug.c            |    6 +++---
>>  3 files changed, 5 insertions(+), 5 deletions(-)
> 
> Probably, the better way is to just remove remove_memory() and use
> offline_pages().

we don't notify the userspace that the memory is offlined in offline_pages().
We reimplement offline_memory(), but ishimatsu doesn't include that patch to
this series.

Thanks
Wen Congyang

> 
> btw, current remove_memory() pfn calculation is just buggy.
> 
> 
>> int remove_memory(u64 start, u64 size)
>> {
>>      unsigned long start_pfn, end_pfn;
>>
>>      start_pfn = PFN_DOWN(start);
>>      end_pfn = start_pfn + PFN_DOWN(size);
> 
> It should be:
> 
>       start_pfn = PFN_DOWN(start);
>       end_pfn = PFN_UP(start + size)
> 
> or
> 
>       start_pfn = PFN_UP(start);
>       end_pfn = PFN_DOWN(start + size)
> 

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to