Re: [Patch v3 2/2] mm/huge_memory: merge uniform_split_supported() and non_uniform_split_supported()

[Zi Yan <ziy@nvidia.com>]

On 5 Nov 2025, at 22:41, Wei Yang wrote:

> The functions uniform_split_supported() and
> non_uniform_split_supported() share significantly similar logic.
>
> The only functional difference is that uniform_split_supported()
> includes an additional check on the requested @new_order.
>
> The reason for this check comes from the following two aspects:
>
>   * some file system or swap cache just supports order-0 folio
>   * the behavioral difference between uniform/non-uniform split
>
> The behavioral difference between uniform split and non-uniform:
>
>   * uniform split splits folio directly to @new_order
>   * non-uniform split creates after-split folios with orders from
>     folio_order(folio) - 1 to new_order.
>
> This means for non-uniform split or !new_order split we should check the
> file system and swap cache respectively.
>
> This commit unifies the logic and merge the two functions into a single
> combined helper, removing redundant code and simplifying the split
> support checking mechanism.
>
> Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
> Cc: Zi Yan <ziy@nvidia.com>
> Cc: "David Hildenbrand (Red Hat)" <david@kernel.org>
>
> ---
> v3:
>   * adjust to use split_type
>   * rebase on Zi Yan fix lkml.kernel.org/r/20251105162910.752266-1-ziy@nvidia.com
> v2:
>   * remove need_check
>   * update comment
>   * add more explanation in change log
> ---
>  include/linux/huge_mm.h |  8 ++---
>  mm/huge_memory.c        | 71 +++++++++++++++++------------------------
>  2 files changed, 33 insertions(+), 46 deletions(-)
>
LGTM. Thanks. Reviewed-by: Zi Yan <ziy@nvidia.com>

Best Regards,
Yan, Zi