From e162956cbeae2587cfe01e4ab424ca67df6b30dc Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Fri, 17 Jun 2022 18:49:59 +0100 Subject: [PATCH] mm: add folios_put() Patch series "Convert the swap code to be more folio-based". There's still more to do with the swap code, but this reaps a lot of the folio benefit. More than 4kB of kernel text saved (with the UEK7 kernel config). I don't know how much that's going to translate into CPU savings, but some of those compound_head() calls are on every page free, so it should be noticable. It might even be noticable just from an I-cache consumption perspective. This patch (of 22): This is just a wrapper around release_pages() for now. Place the prototype in mm.h along with folio_put() and folio_put_refs(). Link: https://lkml.kernel.org/r/20220617175020.717127-1-willy@infradead.org Link: https://lkml.kernel.org/r/20220617175020.717127-2-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton --- include/linux/mm.h | 19 +++++++++++++++++++ include/linux/pagemap.h | 2 -- 2 files changed, 19 insertions(+), 2 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 09ea26056e2f5..09670ccb94e7e 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1220,6 +1220,25 @@ static inline void folio_put_refs(struct folio *folio, int refs) __put_page(&folio->page); } +void release_pages(struct page **pages, int nr); + +/** + * folios_put - Decrement the reference count on an array of folios. + * @folios: The folios. + * @nr: How many folios there are. + * + * Like folio_put(), but for an array of folios. This is more efficient + * than writing the loop yourself as it will optimise the locks which + * need to be taken if the folios are freed. + * + * Context: May be called in process or interrupt context, but not in NMI + * context. May be called while holding a spinlock. + */ +static inline void folios_put(struct folio **folios, unsigned int nr) +{ + release_pages((struct page **)folios, nr); +} + static inline void put_page(struct page *page) { struct folio *folio = page_folio(page); diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index ce96866fbec40..c399a9c5da7d4 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -345,8 +345,6 @@ static inline void filemap_nr_thps_dec(struct address_space *mapping) #endif } -void release_pages(struct page **pages, int nr); - struct address_space *page_mapping(struct page *); struct address_space *folio_mapping(struct folio *); struct address_space *swapcache_mapping(struct folio *); -- 2.39.5