Re: [PATCH 3/4] mm/readahead: add a_ops->ra_folio_order to get a desired folio order

Matthew Wilcox
2025-12-01T21:20:03Z

On Mon, Dec 01, 2025 at 09:01:26PM +0000, Jaegeuk Kim wrote:
> This patch introduces a new address operation, a_ops->ra_folio_order(), which
> proposes a new folio order based on the adjusted order for page_cache_sync_ra.
>
> Hence, each filesystem can set the desired minimum order of folio allocation
> when requesting fadvise(POSIX_FADV_WILLNEED).

Again, you've said what but not why. Does the mm code not ramp up the
folio order sufficiently quickly? What are you trying to accomplish?