Re: [PATCH 2/2] driver: dma-buf: use alloc_pages_bulk_list for order-0 allocation

[Zhaoyang Huang]

On Wed, Oct 15, 2025 at 11:21 AM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:
>
> On Wed, Oct 15, 2025 at 09:12:07AM +0800, Zhaoyang Huang wrote:
> > > Could be that we need to make this behavior conditional, but somebody would need to come up with some really good arguments to justify the complexity.
> > ok, should we use CONFIG_DMA_BUF_BULK_ALLOCATION or a variable
> > controlled by sysfs interface?
>
> No.  Explain what you're trying to solve, because you haven't yet.
Dma-buf works as a memory allocation backend could loop thousands of
times alloc_pages for allocating order-0 pages to fulfill the dozens
MB demand, this commit would like to replace the loop by once
alloc_pages_bulk. Whereas, alloc_pages_bulk_array perhaps introduces
extra memory allocation along with direct-reclaim which could be more
expensive than iterating the list. so call back the API
alloc_pages_bulk_list as well