From 32e7ba1ea1f8d1f0ea4983e768f8b566770a55b3 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Fri, 6 Nov 2015 16:29:47 -0800 Subject: zsmalloc: use page->private instead of page->first_page We are going to rework how compound_head() work. It will not use page->first_page as we have it now. The only other user of page->first_page beyond compound pages is zsmalloc. Let's use page->private instead of page->first_page here. It occupies the same storage space. Signed-off-by: Kirill A. Shutemov Acked-by: Vlastimil Babka Reviewed-by: Sergey Senozhatsky Reviewed-by: Andrea Arcangeli Cc: "Paul E. McKenney" Cc: Andi Kleen Cc: Aneesh Kumar K.V Cc: Christoph Lameter Cc: David Rientjes Cc: Hugh Dickins Cc: Joonsoo Kim Cc: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/zsmalloc.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) (limited to 'mm/zsmalloc.c') diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index 2858b20dce76..9f15bdd9163c 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -16,7 +16,7 @@ * struct page(s) to form a zspage. * * Usage of struct page fields: - * page->first_page: points to the first component (0-order) page + * page->private: points to the first component (0-order) page * page->index (union with page->freelist): offset of the first object * starting in this page. For the first page, this is * always 0, so we use this field (aka freelist) to point @@ -26,8 +26,7 @@ * * For _first_ page only: * - * page->private (union with page->first_page): refers to the - * component page after the first page + * page->private: refers to the component page after the first page * If the page is first_page for huge object, it stores handle. * Look at size_class->huge. * page->freelist: points to the first free object in zspage. @@ -774,7 +773,7 @@ static struct page *get_first_page(struct page *page) if (is_first_page(page)) return page; else - return page->first_page; + return (struct page *)page_private(page); } static struct page *get_next_page(struct page *page) @@ -959,7 +958,7 @@ static struct page *alloc_zspage(struct size_class *class, gfp_t flags) * Allocate individual pages and link them together as: * 1. first page->private = first sub-page * 2. all sub-pages are linked together using page->lru - * 3. each sub-page is linked to the first page using page->first_page + * 3. each sub-page is linked to the first page using page->private * * For each size class, First/Head pages are linked together using * page->lru. Also, we set PG_private to identify the first page @@ -984,7 +983,7 @@ static struct page *alloc_zspage(struct size_class *class, gfp_t flags) if (i == 1) set_page_private(first_page, (unsigned long)page); if (i >= 1) - page->first_page = first_page; + set_page_private(page, (unsigned long)first_page); if (i >= 2) list_add(&page->lru, &prev_page->lru); if (i == class->pages_per_zspage - 1) /* last page */ -- cgit