Re: [PATCH 1/2] mm: call back alloc_pages_bulk_list since it is useful

[David Hildenbrand]

On 14.10.25 10:32, zhaoyang.huang wrote:
> From: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx>

Probably the subject should be "mm: reintroduce alloc_pages_bulk_list()"

> commit c8b979530f27 ("mm: alloc_pages_bulk_noprof: drop page_list
> argument") drops alloc_pages_bulk_list. This commit would like to call back
> it since it is proved to be helpful to the drivers which allocate a bulk of
> pages(see patch of 2 in this series ).

"Let's reintroduce it so we can us for bulk allocation in the context of 
XXX next."

> I do notice that Matthew's comment of the time cost of iterating a list.
> However, I also observed in our test that the extra page_array's allocation
> could be more expensive than cpu iteration when direct reclaiming happens
> when ram is low[1]. IMHO, could we leave the API here to have the users
> choose between the array or list according to their scenarios.

I'd prefer if we avoid reintroducing this interface.

How many pages are you intending to allocate? Wouldn't a smaller array 
on the stack be sufficient?


--
Cheers

David / dhildenb