Hi Kosaki-san,

2012/06/28 14:27, KOSAKI Motohiro wrote:

On Thu, Jun 28, 2012 at 1:06 AM, Yasuaki Ishimatsu
[off-list ref] wrote:

quoted

Hi Wen,

2012/06/27 17:49, Wen Congyang wrote:

quoted

At 06/27/2012 01:44 PM, Yasuaki Ishimatsu Wrote:

quoted

When offline_pages() is called to offlined memory, the function fails since
all memory has been offlined. In this case, the function should succeed.
The patch adds the check function into offline_pages().

You miss such case: some pages are online, while some pages are offline.
offline_pages() will fail too in such case.

You are right. But current code fails, when the function is called to offline
memory. In this case, the function should succeed. So the patch confirms
whether the memory was offlined or not. And if memory has already been
offlined, offline_pages return 0.

Can you please explain why the caller can't check it? I hope to avoid
an ignorance
as far as we can.

Of course, caller side can check it. But there is a possibility that
offline_pages() is called by many functions. So I do not think that it
is good that all functions which call offline_pages() check it.

Thanks,
Yasuaki Ishimatsu