[PATCH 1/2] makedumpfile: Add description of pages lost by ENOSPACE in IMPLEMENTATION

["Zhou, Wenjian/周文剑"]

On 06/29/2015 04:33 PM, Atsushi Kumagai wrote:
> Hello Zhou,
>
>> Currently, there is no obvious description in IMPLEMENTATION for
>> distinguishing the lost pages resulted by ENOSPACE errors or others.
>> So, it is added.
>>
>> Signed-off-by: Zhou Wenjian<zhouwj-fnst at cn.fujitsu.com>
>> ---
>> IMPLEMENTATION |    2 ++
>> 1 files changed, 2 insertions(+), 0 deletions(-)
>>
>> diff --git a/IMPLEMENTATION b/IMPLEMENTATION
>> index 72df5d5..70a3f7c 100644
>> --- a/IMPLEMENTATION
>> +++ b/IMPLEMENTATION
>> @@ -240,6 +240,8 @@
>>      The page header and page data are written in pairs. When writing page data
>>      (pfn N+1), if ENOSPACE error happens, the page headers after N won't be
>>      written either.
>> +    When reading page from incomplete core, only the page lost by ENOSPACE errors
>> +    has 0 in its corresponding page descriptor's member offset.
>
> I'm not sure this is correct.
> Could you point me where is the code which sets 0 to the page_desc->offset
> of the lost page ?
>

There is no code to set it. Since the data lost is filled with zero when it is read,
the page_desc->offset will also be zero.
And zero page has its own offset not equal 0. So we can distinguish them with their
member offset.

-- 
Thanks
Zhou Wenjian