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. > 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.