diff options
| -rw-r--r-- | lib/Kconfig.debug | 3 | ||||
| -rw-r--r-- | mm/page_alloc.c | 26 |
2 files changed, 21 insertions, 8 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 156822e3cc79..1cedc2356b78 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -172,7 +172,8 @@ config DEBUG_VM bool "Debug VM" depends on DEBUG_KERNEL help - Enable this to debug the virtual-memory system. + Enable this to turn on extended checks in the virtual-memory system + that may impact performance. If unsure, say N. diff --git a/mm/page_alloc.c b/mm/page_alloc.c index b0647b515277..088712f2ac02 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -81,6 +81,7 @@ int min_free_kbytes = 1024; unsigned long __initdata nr_kernel_pages; unsigned long __initdata nr_all_pages; +#ifdef CONFIG_DEBUG_VM static int page_outside_zone_boundaries(struct zone *zone, struct page *page) { int ret = 0; @@ -122,6 +123,13 @@ static int bad_range(struct zone *zone, struct page *page) return 0; } +#else +static inline int bad_range(struct zone *zone, struct page *page) +{ + return 0; +} +#endif + static void bad_page(const char *function, struct page *page) { printk(KERN_EMERG "Bad page state at %s (in process '%s', page %p)\n", @@ -255,14 +263,20 @@ __find_combined_index(unsigned long page_idx, unsigned int order) /* * This function checks whether a page is free && is the buddy * we can do coalesce a page and its buddy if - * (a) the buddy is free && - * (b) the buddy is on the buddy system && - * (c) a page and its buddy have the same order. + * (a) the buddy is not in a hole && + * (b) the buddy is free && + * (c) the buddy is on the buddy system && + * (d) a page and its buddy have the same order. * for recording page's order, we use page_private(page) and PG_private. * */ static inline int page_is_buddy(struct page *page, int order) { +#ifdef CONFIG_HOLES_IN_ZONE + if (!pfn_valid(page_to_pfn(page))) + return 0; +#endif + if (PagePrivate(page) && (page_order(page) == order) && page_count(page) == 0) @@ -314,17 +328,15 @@ static inline void __free_pages_bulk (struct page *page, struct free_area *area; struct page *buddy; - combined_idx = __find_combined_index(page_idx, order); buddy = __page_find_buddy(page, page_idx, order); - - if (bad_range(zone, buddy)) - break; if (!page_is_buddy(buddy, order)) break; /* Move the buddy up one level. */ + list_del(&buddy->lru); area = zone->free_area + order; area->nr_free--; rmv_page_order(buddy); + combined_idx = __find_combined_index(page_idx, order); page = page + (combined_idx - page_idx); page_idx = combined_idx; order++; |