Commit 02d65d6f authored by Sidhartha Kumar's avatar Sidhartha Kumar Committed by Andrew Morton
Browse files

mm: introduce folio_is_pfmemalloc 

Add a folio equivalent for page_is_pfmemalloc. This removes two instances
of page_is_pfmemalloc(folio_page(folio, 0)) so the folio can be used
directly.

Link: https://lkml.kernel.org/r/20230106215251.599222-1-sidhartha.kumar@oracle.com


Suggested-by: default avatarMatthew Wilcox <willy@infradead.org>
Signed-off-by: default avatarSidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: default avatarSeongJae Park <sj@kernel.org>
Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 17e81022

include/linux/mm.h

+15 −0
Original line number Diff line number Diff line
@@ -1926,6 +1926,21 @@ static inline bool page_is_pfmemalloc(const struct page *page) 
	return (uintptr_t)page->lru.next & BIT(1);

}



/*

 * Return true only if the folio has been allocated with

 * ALLOC_NO_WATERMARKS and the low watermark was not

 * met implying that the system is under some pressure.

 */

static inline bool folio_is_pfmemalloc(const struct folio *folio)

{

	/*

	 * lru.next has bit 1 set if the page is allocated from the

	 * pfmemalloc reserves.  Callers may simply overwrite it if

	 * they do not need to preserve that information.

	 */

	return (uintptr_t)folio->lru.next & BIT(1);

}



/*

 * Only to be called by the page allocator on a freshly allocated

 * page.

mm/slab.c

+1 −1
Original line number Diff line number Diff line
@@ -1373,7 +1373,7 @@ static struct slab *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, 
	/* Make the flag visible before any changes to folio->mapping */

	smp_wmb();

	/* Record if ALLOC_NO_WATERMARKS was set when allocating the slab */

	if (sk_memalloc_socks() && page_is_pfmemalloc(folio_page(folio, 0)))

	if (sk_memalloc_socks() && folio_is_pfmemalloc(folio))

		slab_set_pfmemalloc(slab);



	return slab;

mm/slub.c

+1 −1
Original line number Diff line number Diff line
@@ -1859,7 +1859,7 @@ static inline struct slab *alloc_slab_page(gfp_t flags, int node, 
	__folio_set_slab(folio);

	/* Make the flag visible before any changes to folio->mapping */

	smp_wmb();

	if (page_is_pfmemalloc(folio_page(folio, 0)))

	if (folio_is_pfmemalloc(folio))

		slab_set_pfmemalloc(slab);



	return slab;