Re: [Question Resend] About z3fold page migration
From: linmiaohe
Date: Mon Oct 12 2020 - 22:42:08 EST
Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:
> On Mon, Oct 12, 2020 at 02:00:17PM +0000, linmiaohe wrote:
>> Hi all:
>>
>> Many thanks for brilliant z3fold code. I am reading it and have some questions about it. It's very nice of you if you can explain it for me.
>> 1.page->private is used in z3fold but PagePrivate flag is never set, should we SetPagePrivate for it?
>
>No. SetPagePrivate and page->private are related in interesting and complicated ways. I'm working on some documentation for it at the moment, but the short answer is: no.
I can't wait to read your document. PagePrivate confuses me now.
>
>> 2.Since PagePrivate flag is never set, why we ClearPagePrivate in free_z3fold_page and z3fold_page_migrate?
>
>That's probably a bug.
>
>
>> 3.Should we add page to the unbuddied list in z3fold_page_putback()
>> when zhdr->refcount does not reach 0 since we remove it from unbuddied list in z3fold_page_isolate? Or When we will add page to the unbuddied list after z3fold_page_putback?
>
>This one I do not know the answer to.
>
Many thanks for your reply. Enjoy your day! ;)