Re: [PATCH 5/7] mm: add new 'orders' parameter for find_get_entries() and find_lock_entries()

[Baolin Wang]

On 2024/6/11 00:59, Matthew Wilcox wrote:
> On Thu, Jun 06, 2024 at 07:58:55PM +0800, Baolin Wang wrote:
> > In the following patches, shmem will support the swap out of large folios,
> > which means the shmem mappings may contain large order swap entries, so an
> > 'orders' array is added for find_get_entries() and find_lock_entries() to
> > obtain the order size of shmem swap entries, which will help in the release
> > of shmem large folio swap entries.
>
> I am not a fan.

With Daniel's suggestion, I think I can drop the 'order' parameter if 
you don't like it.

I was hoping that 'order' would be encoded in the swap
> entry, not passed as a separate parameter.
>
> As I understand it, we currently have a free bit, or
> swp_to_radix_entry() would not work.  We can use that as detailed
> here to encode the order in a single bit.
>
> https://kernelnewbies.org/MatthewWilcox/NaturallyAlignedOrder

OK. This seems to deserve a separate patch set. I will look at your 
suggestion in detail. Thanks.