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

David Hildenbrand
2023-12-05T16:36:02Z

> 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