Re: [PATCH v2 2/3] mm, page_owner: decouple freeing stack trace from debug_pagealloc

Vlastimil Babka
2019-10-01T12:35:19Z

On 10/1/19 2:32 PM, Vlastimil Babka wrote:
> On 10/1/19 2:26 PM, Qian Cai wrote:
>> On Tue, 2019-10-01 at 14:51 +0300, Kirill A. Shutemov wrote:
>>> On Tue, Oct 01, 2019 at 10:07:44AM +0200, Vlastimil Babka wrote:
>>>> On 10/1/19 1:49 AM, Qian Cai wrote:
>>>
>>> DEBUG_PAGEALLOC is much more intrusive debug option. Not all architectures
>>> support it in an efficient way. Some require hibernation.
>>>
>>> I don't see a reason to tie these two option together.
>>
>> Make sense. How about page_owner=on will have page_owner_free=on by default?
>> That way we don't need the extra parameter.
>
> There were others that didn't want that overhead (memory+cpu) always. So the
> last version is as flexible as we can get, IMHO, before approaching bikeshed
> territory. It's just another parameter.

Or suggest how to replace page_owner=on with something else (page_owner=full?)
and I can change that. But I don't want to implement a variant where we store only
the freeing stack, though.