Re: [PATCH] mm/page_ext: init page_ext early if there are no deferred struct pages

From: Pasha Tatashin
Date: Wed Jan 18 2023 - 10:04:29 EST


On Tue, Jan 17, 2023 at 8:13 PM Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> On Tue, 17 Jan 2023 20:46:17 +0000 Pasha Tatashin <pasha.tatashin@xxxxxxxxxx> wrote:
>
> > page_ext must be initialized after all struct pages are initialized.
> > Therefore, page_ext is initialized after page_alloc_init_late(), and
> > can optionally be initialized earlier via early_page_ext kernel
> > parameter which as a side effect also disables deferred struct pages.
> >
> > Allow to automatically init page_ext early when there are no deferred
> > struct pages in order to be able to use page_ext during kernel boot
> > and track for example page allocations early.
>
> Compilation blows up with CONFIG_PAGE_EXTENSION=n. I did

Thanks, I will update the patch and send it soon.

Pasha