Re: [PATCH -V3 4/5] swap: remove get/put_swap_device() in __swap_duplicate()

[David Hildenbrand]

On 29.05.23 08:13, Huang Ying wrote:
> __swap_duplicate() is called by
>
> - swap_shmem_alloc(): the folio in swap cache is locked.
>
> - copy_nonpresent_pte() -> swap_duplicate() and try_to_unmap_one() ->
>    swap_duplicate(): the page table lock is held.
>
> - __read_swap_cache_async() -> swapcache_prepare(): enclosed with
>    get/put_swap_device() in __read_swap_cache_async() already.
>
> So, it's safe to remove get/put_swap_device() in __swap_duplicate().
>
> Signed-off-by: "Huang, Ying" <ying.huang@xxxxxxxxx>
> Reviewed-by: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
> Cc: David Hildenbrand <david@xxxxxxxxxx>
> Cc: Hugh Dickins <hughd@xxxxxxxxxx>
> Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
> Cc: Michal Hocko <mhocko@xxxxxxxx>
> Cc: Minchan Kim <minchan@xxxxxxxxxx>
> Cc: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx>
> Cc: Yang Shi <shy828301@xxxxxxxxx>
> Cc: Yu Zhao <yuzhao@xxxxxxxxxx>
> Cc: Chris Li <chrisl@xxxxxxxxxx>
> ---

Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>

--
Thanks,

David / dhildenb