From 2847cf95c68fa5fa391c58a669e761c4b0c8fc57 Mon Sep 17 00:00:00 2001 From: Joonsoo Kim Date: Fri, 12 Dec 2014 16:55:01 -0800 Subject: [PATCH] mm/debug-pagealloc: cleanup page guard code Page guard is used by debug-pagealloc feature. Currently, it is open-coded, but, I think that more abstraction of it makes core page allocator code more readable. There is no functional difference. Signed-off-by: Joonsoo Kim Acked-by: Vlastimil Babka Cc: Gioh Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 38 +++++++++++++++++++------------------- 1 file changed, 19 insertions(+), 19 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index df542feaac3b..2e8b7f39605a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -439,18 +439,29 @@ static int __init debug_guardpage_minorder_setup(char *buf) } __setup("debug_guardpage_minorder=", debug_guardpage_minorder_setup); -static inline void set_page_guard_flag(struct page *page) +static inline void set_page_guard(struct zone *zone, struct page *page, + unsigned int order, int migratetype) { __set_bit(PAGE_DEBUG_FLAG_GUARD, &page->debug_flags); + INIT_LIST_HEAD(&page->lru); + set_page_private(page, order); + /* Guard pages are not available for any usage */ + __mod_zone_freepage_state(zone, -(1 << order), migratetype); } -static inline void clear_page_guard_flag(struct page *page) +static inline void clear_page_guard(struct zone *zone, struct page *page, + unsigned int order, int migratetype) { __clear_bit(PAGE_DEBUG_FLAG_GUARD, &page->debug_flags); + set_page_private(page, 0); + if (!is_migrate_isolate(migratetype)) + __mod_zone_freepage_state(zone, (1 << order), migratetype); } #else -static inline void set_page_guard_flag(struct page *page) { } -static inline void clear_page_guard_flag(struct page *page) { } +static inline void set_page_guard(struct zone *zone, struct page *page, + unsigned int order, int migratetype) {} +static inline void clear_page_guard(struct zone *zone, struct page *page, + unsigned int order, int migratetype) {} #endif static inline void set_page_order(struct page *page, unsigned int order) @@ -581,12 +592,7 @@ static inline void __free_one_page(struct page *page, * merge with it and move up one order. */ if (page_is_guard(buddy)) { - clear_page_guard_flag(buddy); - set_page_private(buddy, 0); - if (!is_migrate_isolate(migratetype)) { - __mod_zone_freepage_state(zone, 1 << order, - migratetype); - } + clear_page_guard(zone, buddy, order, migratetype); } else { list_del(&buddy->lru); zone->free_area[order].nr_free--; @@ -861,23 +867,17 @@ static inline void expand(struct zone *zone, struct page *page, size >>= 1; VM_BUG_ON_PAGE(bad_range(zone, &page[size]), &page[size]); -#ifdef CONFIG_DEBUG_PAGEALLOC - if (high < debug_guardpage_minorder()) { + if (IS_ENABLED(CONFIG_DEBUG_PAGEALLOC) && + high < debug_guardpage_minorder()) { /* * Mark as guard pages (or page), that will allow to * merge back to allocator when buddy will be freed. * Corresponding page table entries will not be touched, * pages will stay not present in virtual address space */ - INIT_LIST_HEAD(&page[size].lru); - set_page_guard_flag(&page[size]); - set_page_private(&page[size], high); - /* Guard pages are not available for any usage */ - __mod_zone_freepage_state(zone, -(1 << high), - migratetype); + set_page_guard(zone, &page[size], high, migratetype); continue; } -#endif list_add(&page[size].lru, &area->free_list[migratetype]); area->nr_free++; set_page_order(&page[size], high); -- 2.20.1