On Mon, May 17, 2021 at 4:37 PM Linus Torvalds
<torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> I don't mind that rule, but what's the advantage of introducing a new
> name for that? IOW, I get the feeling that almost all of this
> could/should just be "don't use non-head pages".
Put another way: I've often wanted to remove the (quite expensive)
"compund_head()" calls out of the code page functions, and move them
into the callers (and in most cases they probably just end up
disappearing entirely, because the callers fundamentally always have a
proper head page).
It feels like this is what the folio patches do, they just spend a
*lot* of effort doing so incrementally by renaming things and
duplicating functionality, rather than just do it (again
incrementally) by just doing one compound_head() movement at a time..
Linus
