Messages in this thread | | | Date | Tue, 2 Mar 2021 13:22:49 +0000 | From | Matthew Wilcox <> | Subject | Re: [PATCH v3 01/25] mm: Introduce struct folio |
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On Mon, Mar 01, 2021 at 03:26:11PM -0500, Zi Yan wrote: > > +static inline struct folio *next_folio(struct folio *folio) > > +{ > > + return folio + folio_nr_pages(folio); > > Are you planning to make hugetlb use folio too? > > If yes, this might not work if we have CONFIG_SPARSEMEM && !CONFIG_SPARSEMEM_VMEMMAP > with a hugetlb folio > MAX_ORDER, because struct page might not be virtually contiguous. > See the experiment I did in [1].
Actually, how about proofing this against a future change?
static inline struct folio *next_folio(struct folio *folio) { #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP) pfn_t next_pfn = page_to_pfn(&folio->page) + folio_nr_pages(folio); return (struct folio *)pfn_to_page(next_pfn); #else return folio + folio_nr_pages(folio); #endif }
(not compiled)
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