Commit 2d4894b5 authored by Mel Gorman's avatar Mel Gorman Committed by Linus Torvalds
Browse files

mm: remove cold parameter from free_hot_cold_page* 

Most callers users of free_hot_cold_page claim the pages being released
are cache hot.  The exception is the page reclaim paths where it is
likely that enough pages will be freed in the near future that the
per-cpu lists are going to be recycled and the cache hotness information
is lost.  As no one really cares about the hotness of pages being
released to the allocator, just ditch the parameter.

The APIs are renamed to indicate that it's no longer about hot/cold
pages.  It should also be less confusing as there are subtle differences
between them.  __free_pages drops a reference and frees a page when the
refcount reaches zero.  free_hot_cold_page handled pages whose refcount
was already zero which is non-obvious from the name.  free_unref_page
should be more obvious.

No performance impact is expected as the overhead is marginal.  The
parameter is removed simply because it is a bit stupid to have a useless
parameter copied everywhere.

[mgorman@techsingularity.net: add pages to head, not tail]
  Link: http://lkml.kernel.org/r/20171019154321.qtpzaeftoyyw4iey@techsingularity.net
Link: http://lkml.kernel.org/r/20171018075952.10627-8-mgorman@techsingularity.net


Signed-off-by: default avatarMel Gorman <mgorman@techsingularity.net>
Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent c6f92f9f

arch/powerpc/mm/mmu_context_book3s64.c

+1 −1
Original line number Diff line number Diff line
@@ -200,7 +200,7 @@ static void destroy_pagetable_page(struct mm_struct *mm) 
	/* We allow PTE_FRAG_NR fragments from a PTE page */

	if (page_ref_sub_and_test(page, PTE_FRAG_NR - count)) {

		pgtable_page_dtor(page);

		free_hot_cold_page(page, 0);

		free_unref_page(page);

	}

}

arch/powerpc/mm/pgtable_64.c

+1 −1
Original line number Diff line number Diff line
@@ -404,7 +404,7 @@ void pte_fragment_free(unsigned long *table, int kernel) 
	if (put_page_testzero(page)) {

		if (!kernel)

			pgtable_page_dtor(page);

		free_hot_cold_page(page, 0);

		free_unref_page(page);

	}

}

arch/sparc/mm/init_64.c

+1 −1
Original line number Diff line number Diff line
@@ -2939,7 +2939,7 @@ pgtable_t pte_alloc_one(struct mm_struct *mm, 
	if (!page)

		return NULL;

	if (!pgtable_page_ctor(page)) {

		free_hot_cold_page(page, 0);

		free_unref_page(page);

		return NULL;

	}

	return (pte_t *) page_address(page);

arch/tile/mm/homecache.c

+1 −1
Original line number Diff line number Diff line
@@ -409,7 +409,7 @@ void __homecache_free_pages(struct page *page, unsigned int order) 
	if (put_page_testzero(page)) {

		homecache_change_page_home(page, order, PAGE_HOME_HASH);

		if (order == 0) {

			free_hot_cold_page(page, false);

			free_unref_page(page);

		} else {

			init_page_count(page);

			__free_pages(page, order);

include/linux/gfp.h

+2 −2
Original line number Diff line number Diff line
@@ -530,8 +530,8 @@ void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask); 


extern void __free_pages(struct page *page, unsigned int order);

extern void free_pages(unsigned long addr, unsigned int order);

extern void free_hot_cold_page(struct page *page, bool cold);

extern void free_hot_cold_page_list(struct list_head *list, bool cold);

extern void free_unref_page(struct page *page);

extern void free_unref_page_list(struct list_head *list);



struct page_frag_cache;

extern void __page_frag_cache_drain(struct page *page, unsigned int count);