Commit e3c4cebf authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Andrew Morton
Browse files

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: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent a83f0551

include/linux/mm.h

+19 −0
Original line number Diff line number Diff line
@@ -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);

include/linux/pagemap.h

+0 −2
Original line number Diff line number Diff line
@@ -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 *);