Re: [PATCH] MAINTAINERS: add mm THP section

From: Matthew Wilcox
Date: Thu Apr 24 2025 - 13:57:38 EST


On Thu, Apr 24, 2025 at 12:16:32PM +0100, Lorenzo Stoakes wrote:
> As part of the ongoing efforts to sub-divide memory management
> maintainership and reviewership, establish a section for Transparent Huge
> Page support and add appropriate maintainers and reviewers.

I'm quite queasy about this. I'm doing my best to make "THP" disappear
as a concept. How would you define what THP is? Originally, it was
PMD-sized-and-aligned allocations, and some of the way we expose it to
userspace, that's still the interpretation. But we also have folios which
are of some hardware-defined magic sizes, as well as (for filesystems,
at least) random other non-zero orders.

Memory is just managed in variously sized quantities. There should be
nothing magic about "THP", and I'm still annoyed at the anon-mem people
for baking various magic sizes into user-visible APIs.