Commit ffedd09f authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Vlastimil Babka
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zsmalloc: Stop using slab fields in struct page 



The ->freelist and ->units members of struct page are for the use of
slab only.  I'm not particularly familiar with zsmalloc, so generate the
same code by using page->index to store 'page' (page->index and
page->freelist are at the same offset in struct page).  This should be
cleaned up properly at some point by somebody who is familiar with
zsmalloc.

Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarVlastimil Babka <vbabka@suse.cz>
Acked-by: default avatarMinchan Kim <minchan@kernel.org>
Acked-by: default avatarJohannes Weiner <hannes@cmpxchg.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
parent 9c01e9af

mm/zsmalloc.c

+9 −9
Original line number Diff line number Diff line
@@ -17,10 +17,10 @@ 
 *

 * Usage of struct page fields:

 *	page->private: points to zspage

 *	page->freelist(index): links together all component pages of a zspage

 *	page->index: links together all component pages of a zspage

 *		For the huge page, this is always 0, so we use this field

 *		to store handle.

 *	page->units: first object offset in a subpage of zspage

 *	page->page_type: first object offset in a subpage of zspage

 *

 * Usage of struct page flags:

 *	PG_private: identifies the first component page
@@ -489,12 +489,12 @@ static inline struct page *get_first_page(struct zspage *zspage) 


static inline int get_first_obj_offset(struct page *page)

{

	return page->units;

	return page->page_type;

}



static inline void set_first_obj_offset(struct page *page, int offset)

{

	page->units = offset;

	page->page_type = offset;

}



static inline unsigned int get_freeobj(struct zspage *zspage)
@@ -827,7 +827,7 @@ static struct page *get_next_page(struct page *page) 
	if (unlikely(PageHugeObject(page)))

		return NULL;



	return page->freelist;

	return (struct page *)page->index;

}



/**
@@ -901,7 +901,7 @@ static void reset_page(struct page *page) 
	set_page_private(page, 0);

	page_mapcount_reset(page);

	ClearPageHugeObject(page);

	page->freelist = NULL;

	page->index = 0;

}



static int trylock_zspage(struct zspage *zspage)
@@ -1027,7 +1027,7 @@ static void create_page_chain(struct size_class *class, struct zspage *zspage, 


	/*

	 * Allocate individual pages and link them together as:

	 * 1. all pages are linked together using page->freelist

	 * 1. all pages are linked together using page->index

	 * 2. each sub-page point to zspage using page->private

	 *

	 * we set PG_private to identify the first page (i.e. no other sub-page
@@ -1036,7 +1036,7 @@ static void create_page_chain(struct size_class *class, struct zspage *zspage, 
	for (i = 0; i < nr_pages; i++) {

		page = pages[i];

		set_page_private(page, (unsigned long)zspage);

		page->freelist = NULL;

		page->index = 0;

		if (i == 0) {

			zspage->first_page = page;

			SetPagePrivate(page);
@@ -1044,7 +1044,7 @@ static void create_page_chain(struct size_class *class, struct zspage *zspage, 
					class->pages_per_zspage == 1))

				SetPageHugeObject(page);

		} else {

			prev_page->freelist = page;

			prev_page->index = (unsigned long)page;

		}

		prev_page = page;

	}