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charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: B2D86100006 X-Stat-Signature: s7y87iq6uob3rrzgozdqffupm9t4ffgj X-HE-Tag: 1773132430-594976 X-HE-Meta: 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 5RpeQA5Y JU+dbUqGG5q8+OtULOdPjLGSY74zC71fR3VTqv4Mych0CvOq/YsedLLy2MBOID2pnI9EgWGLCxY+D6dZKpjp5KjCXCQTlARBIwpyKNvNC8qaZLBsESp/S5ksi81HXmo9LZaUopxX8fvrwqSu7AsqghKvKHQLWjSK4k9OYr40230aeR/D+YXDg8WIiE9syChACLCjCNWuvBkJ62UCU5eDMAJ3OZ9FUki9SjbXMrm6CKOx1424xJZJlrGBJD/hNcZILljRQYVonoUtqX5tQqEydgWUuZA== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 10/03/26 1:57 pm, Kairui Song wrote: > On Tue, Mar 10, 2026 at 3:36 PM Dev Jain wrote: >> >> Teach folio_dup_swap to handle a batch of consecutive pages. Note that >> folio_dup_swap already can handle a subset of this: nr_pages == 1 and >> nr_pages == folio_nr_pages(folio). Generalize this to any nr_pages. > > Thanks a lot for doing this. I was thinking it's about time we respin > the batch unmapping of anon folios idea. Barry tried that before with > an RFC, and now batching from swap side is easier, so some parts can > be done cleaner. > >> Currently we have a not-so-nice logic of passing in subpage == NULL if >> we mean to exercise the logic on the entire folio, and subpage != NULL if >> we want to exercise the logic on only that subpage. Remove this >> indirection, and explicitly pass subpage != NULL, and the number of >> pages required. > > I was hoping most callers will just use the whole folio, but after > checking your code, yeah, using explicit subpage and nr does fit the > other parts better. > >> diff --git a/mm/swapfile.c b/mm/swapfile.c >> index 915bc93964dbd..eaf61ae6c3817 100644 >> --- a/mm/swapfile.c >> +++ b/mm/swapfile.c >> @@ -1738,7 +1738,8 @@ int folio_alloc_swap(struct folio *folio) >> /** >> * folio_dup_swap() - Increase swap count of swap entries of a folio. >> * @folio: folio with swap entries bounded. >> - * @subpage: if not NULL, only increase the swap count of this subpage. >> + * @subpage: Increase the swap count of this subpage till nr number of >> + * pages forward. > > The new nr_pages parameter isn't documented in the kernel-doc comment? Oops, will add this in v2, thanks.