Re: [PATCH v8 04/10] mm: thp: Support allocation of anonymous multi-size THP

From: David Hildenbrand
Date: Tue Dec 05 2023 - 11:35:30 EST


Comment: Both will eventually loop over all orders, correct? Could
eventually be sped up in the future.

Nit: the orders = ... order = ... looks like this might deserve a helper
function that makes this easier to read.

Nit: Why call thp_vma_suitable_orders if the orders are already 0?
Again, some helper might be reasonable where that is handled internally.

Comment: For order-0 we'll always perform a function call to both
thp_vma_allowable_orders() / thp_vma_suitable_orders(). We should
perform some fast and efficient check if any <PMD THP are even enabled
in the system / for this VMA, and in that case just fallback before
doing more expensive checks.

Correction: only a call to thp_vma_allowable_orders(). I wonder if we can move some of thp_vma_allowable_orders() into the header file where we'd just check as fast and as efficiently for "no THP < PMD_THP enabled" on this system.

--
Cheers,

David / dhildenb