diff options
Diffstat (limited to 'mm/page_alloc.c')
| -rw-r--r-- | mm/page_alloc.c | 4779 |
1 files changed, 4779 insertions, 0 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c new file mode 100644 index 0000000..566ee21 --- /dev/null +++ b/mm/page_alloc.c @@ -0,0 +1,4779 @@ +/* + * linux/mm/page_alloc.c + * + * Manages the free list, the system allocates free pages here. + * Note that kmalloc() lives in slab.c + * + * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds + * Swap reorganised 29.12.95, Stephen Tweedie + * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999 + * Reshaped it to be a zoned allocator, Ingo Molnar, Red Hat, 1999 + * Discontiguous memory support, Kanoj Sarcar, SGI, Nov 1999 + * Zone balancing, Kanoj Sarcar, SGI, Jan 2000 + * Per cpu hot/cold page lists, bulk allocation, Martin J. Bligh, Sept 2002 + * (lots of bits borrowed from Ingo Molnar & Andrew Morton) + */ + +#include <linux/stddef.h> +#include <linux/mm.h> +#include <linux/swap.h> +#include <linux/interrupt.h> +#include <linux/pagemap.h> +#include <linux/jiffies.h> +#include <linux/bootmem.h> +#include <linux/compiler.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/suspend.h> +#include <linux/pagevec.h> +#include <linux/blkdev.h> +#include <linux/slab.h> +#include <linux/oom.h> +#include <linux/notifier.h> +#include <linux/topology.h> +#include <linux/sysctl.h> +#include <linux/cpu.h> +#include <linux/cpuset.h> +#include <linux/memory_hotplug.h> +#include <linux/nodemask.h> +#include <linux/vmalloc.h> +#include <linux/mempolicy.h> +#include <linux/stop_machine.h> +#include <linux/sort.h> +#include <linux/pfn.h> +#include <linux/backing-dev.h> +#include <linux/fault-inject.h> +#include <linux/page-isolation.h> +#include <linux/page_cgroup.h> +#include <linux/debugobjects.h> + +#include <asm/tlbflush.h> +#include <asm/div64.h> +#include "internal.h" + +/* + * Array of node states. + */ +nodemask_t node_states[NR_NODE_STATES] __read_mostly = { + [N_POSSIBLE] = NODE_MASK_ALL, + [N_ONLINE] = { { [0] = 1UL } }, +#ifndef CONFIG_NUMA + [N_NORMAL_MEMORY] = { { [0] = 1UL } }, +#ifdef CONFIG_HIGHMEM + [N_HIGH_MEMORY] = { { [0] = 1UL } }, +#endif + [N_CPU] = { { [0] = 1UL } }, +#endif /* NUMA */ +}; +EXPORT_SYMBOL(node_states); + +unsigned long totalram_pages __read_mostly; +unsigned long totalreserve_pages __read_mostly; +long nr_swap_pages; +int percpu_pagelist_fraction; + +#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE +int pageblock_order __read_mostly; +#endif + +static void __free_pages_ok(struct page *page, unsigned int order); + +/* + * results with 256, 32 in the lowmem_reserve sysctl: + * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high) + * 1G machine -> (16M dma, 784M normal, 224M high) + * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA + * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL + * HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA + * + * TBD: should special case ZONE_DMA32 machines here - in those we normally + * don't need any ZONE_NORMAL reservation + */ +int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = { +#ifdef CONFIG_ZONE_DMA + 256, +#endif +#ifdef CONFIG_ZONE_DMA32 + 256, +#endif +#ifdef CONFIG_HIGHMEM + 32, +#endif + 32, +}; + +EXPORT_SYMBOL(totalram_pages); + +static char * const zone_names[MAX_NR_ZONES] = { +#ifdef CONFIG_ZONE_DMA + "DMA", +#endif +#ifdef CONFIG_ZONE_DMA32 + "DMA32", +#endif + "Normal", +#ifdef CONFIG_HIGHMEM + "HighMem", +#endif + "Movable", +}; + +int min_free_kbytes = 1024; + +unsigned long __meminitdata nr_kernel_pages; +unsigned long __meminitdata nr_all_pages; +static unsigned long __meminitdata dma_reserve; + +#ifdef CONFIG_ARCH_POPULATES_NODE_MAP + /* + * MAX_ACTIVE_REGIONS determines the maximum number of distinct + * ranges of memory (RAM) that may be registered with add_active_range(). + * Ranges passed to add_active_range() will be merged if possible + * so the number of times add_active_range() can be called is + * related to the number of nodes and the number of holes + */ + #ifdef CONFIG_MAX_ACTIVE_REGIONS + /* Allow an architecture to set MAX_ACTIVE_REGIONS to save memory */ + #define MAX_ACTIVE_REGIONS CONFIG_MAX_ACTIVE_REGIONS + #else + #if MAX_NUMNODES >= 32 + /* If there can be many nodes, allow up to 50 holes per node */ + #define MAX_ACTIVE_REGIONS (MAX_NUMNODES*50) + #else + /* By default, allow up to 256 distinct regions */ + #define MAX_ACTIVE_REGIONS 256 + #endif + #endif + + static struct node_active_region __meminitdata early_node_map[MAX_ACTIVE_REGIONS]; + static int __meminitdata nr_nodemap_entries; + static unsigned long __meminitdata arch_zone_lowest_possible_pfn[MAX_NR_ZONES]; + static unsigned long __meminitdata arch_zone_highest_possible_pfn[MAX_NR_ZONES]; +#ifdef CONFIG_MEMORY_HOTPLUG_RESERVE + static unsigned long __meminitdata node_boundary_start_pfn[MAX_NUMNODES]; + static unsigned long __meminitdata node_boundary_end_pfn[MAX_NUMNODES]; +#endif /* CONFIG_MEMORY_HOTPLUG_RESERVE */ + static unsigned long __initdata required_kernelcore; + static unsigned long __initdata required_movablecore; + static unsigned long __meminitdata zone_movable_pfn[MAX_NUMNODES]; + + /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */ + int movable_zone; + EXPORT_SYMBOL(movable_zone); +#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */ + +#if MAX_NUMNODES > 1 +int nr_node_ids __read_mostly = MAX_NUMNODES; +EXPORT_SYMBOL(nr_node_ids); +#endif + +int page_group_by_mobility_disabled __read_mostly; + +static void set_pageblock_migratetype(struct page *page, int migratetype) +{ + set_pageblock_flags_group(page, (unsigned long)migratetype, + PB_migrate, PB_migrate_end); +} + +#ifdef CONFIG_DEBUG_VM +static int page_outside_zone_boundaries(struct zone *zone, struct page *page) +{ + int ret = 0; + unsigned seq; + unsigned long pfn = page_to_pfn(page); + + do { + seq = zone_span_seqbegin(zone); + if (pfn >= zone->zone_start_pfn + zone->spanned_pages) + ret = 1; + else if (pfn < zone->zone_start_pfn) + ret = 1; + } while (zone_span_seqretry(zone, seq)); + + return ret; +} + +static int page_is_consistent(struct zone *zone, struct page *page) +{ + if (!pfn_valid_within(page_to_pfn(page))) + return 0; + if (zone != page_zone(page)) + return 0; + + return 1; +} +/* + * Temporary debugging check for pages not lying within a given zone. + */ +static int bad_range(struct zone *zone, struct page *page) +{ + if (page_outside_zone_boundaries(zone, page)) + return 1; + if (!page_is_consistent(zone, page)) + return 1; + + return 0; +} +#else +static inline int bad_range(struct zone *zone, struct page *page) +{ + return 0; +} +#endif + +static void bad_page(struct page *page) +{ + printk(KERN_EMERG "Bad page state in process '%s'\n" KERN_EMERG + "page:%p flags:0x%0*lx mapping:%p mapcount:%d count:%d\n", + current->comm, page, (int)(2*sizeof(unsigned long)), + (unsigned long)page->flags, page->mapping, + page_mapcount(page), page_count(page)); + + printk(KERN_EMERG "Trying to fix it up, but a reboot is needed\n" + KERN_EMERG "Backtrace:\n"); + dump_stack(); + page->flags &= ~PAGE_FLAGS_CLEAR_WHEN_BAD; + set_page_count(page, 0); + reset_page_mapcount(page); + page->mapping = NULL; + add_taint(TAINT_BAD_PAGE); +} + +/* + * Higher-order pages are called "compound pages". They are structured thusly: + * + * The first PAGE_SIZE page is called the "head page". + * + * The remaining PAGE_SIZE pages are called "tail pages". + * + * All pages have PG_compound set. All pages have their ->private pointing at + * the head page (even the head page has this). + * + * The first tail page's ->lru.next holds the address of the compound page's + * put_page() function. Its ->lru.prev holds the order of allocation. + * This usage means that zero-order pages may not be compound. + */ + +static void free_compound_page(struct page *page) +{ + __free_pages_ok(page, compound_order(page)); +} + +void prep_compound_page(struct page *page, unsigned long order) +{ + int i; + int nr_pages = 1 << order; + + set_compound_page_dtor(page, free_compound_page); + set_compound_order(page, order); + __SetPageHead(page); + for (i = 1; i < nr_pages; i++) { + struct page *p = page + i; + + __SetPageTail(p); + p->first_page = page; + } +} + +#ifdef CONFIG_HUGETLBFS +void prep_compound_gigantic_page(struct page *page, unsigned long order) +{ + int i; + int nr_pages = 1 << order; + struct page *p = page + 1; + + set_compound_page_dtor(page, free_compound_page); + set_compound_order(page, order); + __SetPageHead(page); + for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) { + __SetPageTail(p); + p->first_page = page; + } +} +#endif + +static void destroy_compound_page(struct page *page, unsigned long order) +{ + int i; + int nr_pages = 1 << order; + + if (unlikely(compound_order(page) != order)) + bad_page(page); + + if (unlikely(!PageHead(page))) + bad_page(page); + __ClearPageHead(page); + for (i = 1; i < nr_pages; i++) { + struct page *p = page + i; + + if (unlikely(!PageTail(p) | + (p->first_page != page))) + bad_page(page); + __ClearPageTail(p); + } +} + +static inline void prep_zero_page(struct page *page, int order, gfp_t gfp_flags) +{ + int i; + + /* + * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO + * and __GFP_HIGHMEM from hard or soft interrupt context. + */ + VM_BUG_ON((gfp_flags & __GFP_HIGHMEM) && in_interrupt()); + for (i = 0; i < (1 << order); i++) + clear_highpage(page + i); +} + +static inline void set_page_order(struct page *page, int order) +{ + set_page_private(page, order); + __SetPageBuddy(page); +} + +static inline void rmv_page_order(struct page *page) +{ + __ClearPageBuddy(page); + set_page_private(page, 0); +} + +/* + * Locate the struct page for both the matching buddy in our + * pair (buddy1) and the combined O(n+1) page they form (page). + * + * 1) Any buddy B1 will have an order O twin B2 which satisfies + * the following equation: + * B2 = B1 ^ (1 << O) + * For example, if the starting buddy (buddy2) is #8 its order + * 1 buddy is #10: + * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10 + * + * 2) Any buddy B will have an order O+1 parent P which + * satisfies the following equation: + * P = B & ~(1 << O) + * + * Assumption: *_mem_map is contiguous at least up to MAX_ORDER + */ +static inline struct page * +__page_find_buddy(struct page *page, unsigned long page_idx, unsigned int order) +{ + unsigned long buddy_idx = page_idx ^ (1 << order); + + return page + (buddy_idx - page_idx); +} + +static inline unsigned long +__find_combined_index(unsigned long page_idx, unsigned int order) +{ + return (page_idx & ~(1 << 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 not in a hole && + * (b) the buddy is in the buddy system && + * (c) a page and its buddy have the same order && + * (d) a page and its buddy are in the same zone. + * + * For recording whether a page is in the buddy system, we use PG_buddy. + * Setting, clearing, and testing PG_buddy is serialized by zone->lock. + * + * For recording page's order, we use page_private(page). + */ +static inline int page_is_buddy(struct page *page, struct page *buddy, + int order) +{ + if (!pfn_valid_within(page_to_pfn(buddy))) + return 0; + + if (page_zone_id(page) != page_zone_id(buddy)) + return 0; + + if (PageBuddy(buddy) && page_order(buddy) == order) { + BUG_ON(page_count(buddy) != 0); + return 1; + } + return 0; +} + +/* + * Freeing function for a buddy system allocator. + * + * The concept of a buddy system is to maintain direct-mapped table + * (containing bit values) for memory blocks of various "orders". + * The bottom level table contains the map for the smallest allocatable + * units of memory (here, pages), and each level above it describes + * pairs of units from the levels below, hence, "buddies". + * At a high level, all that happens here is marking the table entry + * at the bottom level available, and propagating the changes upward + * as necessary, plus some accounting needed to play nicely with other + * parts of the VM system. + * At each level, we keep a list of pages, which are heads of continuous + * free pages of length of (1 << order) and marked with PG_buddy. Page's + * order is recorded in page_private(page) field. + * So when we are allocating or freeing one, we can derive the state of the + * other. That is, if we allocate a small block, and both were + * free, the remainder of the region must be split into blocks. + * If a block is freed, and its buddy is also free, then this + * triggers coalescing into a block of larger size. + * + * -- wli + */ + +static inline void __free_one_page(struct page *page, + struct zone *zone, unsigned int order) +{ + unsigned long page_idx; + int order_size = 1 << order; + int migratetype = get_pageblock_migratetype(page); + + if (unlikely(PageCompound(page))) + destroy_compound_page(page, order); + + page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1); + + VM_BUG_ON(page_idx & (order_size - 1)); + VM_BUG_ON(bad_range(zone, page)); + + __mod_zone_page_state(zone, NR_FREE_PAGES, order_size); + while (order < MAX_ORDER-1) { + unsigned long combined_idx; + struct page *buddy; + + buddy = __page_find_buddy(page, page_idx, order); + if (!page_is_buddy(page, buddy, order)) + break; + + /* Our buddy is free, merge with it and move up one order. */ + list_del(&buddy->lru); + zone->free_area[order].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++; + } + set_page_order(page, order); + list_add(&page->lru, + &zone->free_area[order].free_list[migratetype]); + zone->free_area[order].nr_free++; +} + +static inline int free_pages_check(struct page *page) +{ + free_page_mlock(page); + if (unlikely(page_mapcount(page) | + (page->mapping != NULL) | + (page_count(page) != 0) | + (page->flags & PAGE_FLAGS_CHECK_AT_FREE))) + bad_page(page); + if (PageDirty(page)) + __ClearPageDirty(page); + if (PageSwapBacked(page)) + __ClearPageSwapBacked(page); + /* + * For now, we report if PG_reserved was found set, but do not + * clear it, and do not free the page. But we shall soon need + * to do more, for when the ZERO_PAGE count wraps negative. + */ + return PageReserved(page); +} + +/* + * Frees a list of pages. + * Assumes all pages on list are in same zone, and of same order. + * count is the number of pages to free. + * + * If the zone was previously in an "all pages pinned" state then look to + * see if this freeing clears that state. + * + * And clear the zone's pages_scanned counter, to hold off the "all pages are + * pinned" detection logic. + */ +static void free_pages_bulk(struct zone *zone, int count, + struct list_head *list, int order) +{ + spin_lock(&zone->lock); + zone_clear_flag(zone, ZONE_ALL_UNRECLAIMABLE); + zone->pages_scanned = 0; + while (count--) { + struct page *page; + + VM_BUG_ON(list_empty(list)); + page = list_entry(list->prev, struct page, lru); + /* have to delete it as __free_one_page list manipulates */ + list_del(&page->lru); + __free_one_page(page, zone, order); + } + spin_unlock(&zone->lock); +} + +static void free_one_page(struct zone *zone, struct page *page, int order) +{ + spin_lock(&zone->lock); + zone_clear_flag(zone, ZONE_ALL_UNRECLAIMABLE); + zone->pages_scanned = 0; + __free_one_page(page, zone, order); + spin_unlock(&zone->lock); +} + +static void __free_pages_ok(struct page *page, unsigned int order) +{ + unsigned long flags; + int i; + int reserved = 0; + + for (i = 0 ; i < (1 << order) ; ++i) + reserved += free_pages_check(page + i); + if (reserved) + return; + + if (!PageHighMem(page)) { + debug_check_no_locks_freed(page_address(page),PAGE_SIZE<<order); + debug_check_no_obj_freed(page_address(page), + PAGE_SIZE << order); + } + arch_free_page(page, order); + kernel_map_pages(page, 1 << order, 0); + + local_irq_save(flags); + __count_vm_events(PGFREE, 1 << order); + free_one_page(page_zone(page), page, order); + local_irq_restore(flags); +} + +/* + * permit the bootmem allocator to evade page validation on high-order frees + */ +void __meminit __free_pages_bootmem(struct page *page, unsigned int order) +{ + if (order == 0) { + __ClearPageReserved(page); + set_page_count(page, 0); + set_page_refcounted(page); + __free_page(page); + } else { + int loop; + + prefetchw(page); + for (loop = 0; loop < BITS_PER_LONG; loop++) { + struct page *p = &page[loop]; + + if (loop + 1 < BITS_PER_LONG) + prefetchw(p + 1); + __ClearPageReserved(p); + set_page_count(p, 0); + } + + set_page_refcounted(page); + __free_pages(page, order); + } +} + + +/* + * The order of subdivision here is critical for the IO subsystem. + * Please do not alter this order without good reasons and regression + * testing. Specifically, as large blocks of memory are subdivided, + * the order in which smaller blocks are delivered depends on the order + * they're subdivided in this function. This is the primary factor + * influencing the order in which pages are delivered to the IO + * subsystem according to empirical testing, and this is also justified + * by considering the behavior of a buddy system containing a single + * large block of memory acted on by a series of small allocations. + * This behavior is a critical factor in sglist merging's success. + * + * -- wli + */ +static inline void expand(struct zone *zone, struct page *page, + int low, int high, struct free_area *area, + int migratetype) +{ + unsigned long size = 1 << high; + + while (high > low) { + area--; + high--; + size >>= 1; + VM_BUG_ON(bad_range(zone, &page[size])); + list_add(&page[size].lru, &area->free_list[migratetype]); + area->nr_free++; + set_page_order(&page[size], high); + } +} + +/* + * This page is about to be returned from the page allocator + */ +static int prep_new_page(struct page *page, int order, gfp_t gfp_flags) +{ + if (unlikely(page_mapcount(page) | + (page->mapping != NULL) | + (page_count(page) != 0) | + (page->flags & PAGE_FLAGS_CHECK_AT_PREP))) + bad_page(page); + + /* + * For now, we report if PG_reserved was found set, but do not + * clear it, and do not allocate the page: as a safety net. + */ + if (PageReserved(page)) + return 1; + + page->flags &= ~(1 << PG_uptodate | 1 << PG_error | 1 << PG_reclaim | + 1 << PG_referenced | 1 << PG_arch_1 | + 1 << PG_owner_priv_1 | 1 << PG_mappedtodisk +#ifdef CONFIG_UNEVICTABLE_LRU + | 1 << PG_mlocked +#endif + ); + set_page_private(page, 0); + set_page_refcounted(page); + + arch_alloc_page(page, order); + kernel_map_pages(page, 1 << order, 1); + + if (gfp_flags & __GFP_ZERO) + prep_zero_page(page, order, gfp_flags); + + if (order && (gfp_flags & __GFP_COMP)) + prep_compound_page(page, order); + + return 0; +} + +/* + * Go through the free lists for the given migratetype and remove + * the smallest available page from the freelists + */ +static struct page *__rmqueue_smallest(struct zone *zone, unsigned int order, + int migratetype) +{ + unsigned int current_order; + struct free_area * area; + struct page *page; + + /* Find a page of the appropriate size in the preferred list */ + for (current_order = order; current_order < MAX_ORDER; ++current_order) { + area = &(zone->free_area[current_order]); + if (list_empty(&area->free_list[migratetype])) + continue; + + page = list_entry(area->free_list[migratetype].next, + struct page, lru); + list_del(&page->lru); + rmv_page_order(page); + area->nr_free--; + __mod_zone_page_state(zone, NR_FREE_PAGES, - (1UL << order)); + expand(zone, page, order, current_order, area, migratetype); + return page; + } + + return NULL; +} + + +/* + * This array describes the order lists are fallen back to when + * the free lists for the desirable migrate type are depleted + */ +static int fallbacks[MIGRATE_TYPES][MIGRATE_TYPES-1] = { + [MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE }, + [MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE }, + [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE }, + [MIGRATE_RESERVE] = { MIGRATE_RESERVE, MIGRATE_RESERVE, MIGRATE_RESERVE }, /* Never used */ +}; + +/* + * Move the free pages in a range to the free lists of the requested type. + * Note that start_page and end_pages are not aligned on a pageblock + * boundary. If alignment is required, use move_freepages_block() + */ +static int move_freepages(struct zone *zone, + struct page *start_page, struct page *end_page, + int migratetype) +{ + struct page *page; + unsigned long order; + int pages_moved = 0; + +#ifndef CONFIG_HOLES_IN_ZONE + /* + * page_zone is not safe to call in this context when + * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant + * anyway as we check zone boundaries in move_freepages_block(). + * Remove at a later date when no bug reports exist related to + * grouping pages by mobility + */ + BUG_ON(page_zone(start_page) != page_zone(end_page)); +#endif + + for (page = start_page; page <= end_page;) { + /* Make sure we are not inadvertently changing nodes */ + VM_BUG_ON(page_to_nid(page) != zone_to_nid(zone)); + + if (!pfn_valid_within(page_to_pfn(page))) { + page++; + continue; + } + + if (!PageBuddy(page)) { + page++; + continue; + } + + order = page_order(page); + list_del(&page->lru); + list_add(&page->lru, + &zone->free_area[order].free_list[migratetype]); + page += 1 << order; + pages_moved += 1 << order; + } + + return pages_moved; +} + +static int move_freepages_block(struct zone *zone, struct page *page, + int migratetype) +{ + unsigned long start_pfn, end_pfn; + struct page *start_page, *end_page; + + start_pfn = page_to_pfn(page); + start_pfn = start_pfn & ~(pageblock_nr_pages-1); + start_page = pfn_to_page(start_pfn); + end_page = start_page + pageblock_nr_pages - 1; + end_pfn = start_pfn + pageblock_nr_pages - 1; + + /* Do not cross zone boundaries */ + if (start_pfn < zone->zone_start_pfn) + start_page = page; + if (end_pfn >= zone->zone_start_pfn + zone->spanned_pages) + return 0; + + return move_freepages(zone, start_page, end_page, migratetype); +} + +/* Remove an element from the buddy allocator from the fallback list */ +static struct page *__rmqueue_fallback(struct zone *zone, int order, + int start_migratetype) +{ + struct free_area * area; + int current_order; + struct page *page; + int migratetype, i; + + /* Find the largest possible block of pages in the other list */ + for (current_order = MAX_ORDER-1; current_order >= order; + --current_order) { + for (i = 0; i < MIGRATE_TYPES - 1; i++) { + migratetype = fallbacks[start_migratetype][i]; + + /* MIGRATE_RESERVE handled later if necessary */ + if (migratetype == MIGRATE_RESERVE) + continue; + + area = &(zone->free_area[current_order]); + if (list_empty(&area->free_list[migratetype])) + continue; + + page = list_entry(area->free_list[migratetype].next, + struct page, lru); + area->nr_free--; + + /* + * If breaking a large block of pages, move all free + * pages to the preferred allocation list. If falling + * back for a reclaimable kernel allocation, be more + * agressive about taking ownership of free pages + */ + if (unlikely(current_order >= (pageblock_order >> 1)) || + start_migratetype == MIGRATE_RECLAIMABLE) { + unsigned long pages; + pages = move_freepages_block(zone, page, + start_migratetype); + + /* Claim the whole block if over half of it is free */ + if (pages >= (1 << (pageblock_order-1))) + set_pageblock_migratetype(page, + start_migratetype); + + migratetype = start_migratetype; + } + + /* Remove the page from the freelists */ + list_del(&page->lru); + rmv_page_order(page); + __mod_zone_page_state(zone, NR_FREE_PAGES, + -(1UL << order)); + + if (current_order == pageblock_order) + set_pageblock_migratetype(page, + start_migratetype); + + expand(zone, page, order, current_order, area, migratetype); + return page; + } + } + + /* Use MIGRATE_RESERVE rather than fail an allocation */ + return __rmqueue_smallest(zone, order, MIGRATE_RESERVE); +} + +/* + * Do the hard work of removing an element from the buddy allocator. + * Call me with the zone->lock already held. + */ +static struct page *__rmqueue(struct zone *zone, unsigned int order, + int migratetype) +{ + struct page *page; + + page = __rmqueue_smallest(zone, order, migratetype); + + if (unlikely(!page)) + page = __rmqueue_fallback(zone, order, migratetype); + + return page; +} + +/* + * Obtain a specified number of elements from the buddy allocator, all under + * a single hold of the lock, for efficiency. Add them to the supplied list. + * Returns the number of new pages which were placed at *list. + */ +static int rmqueue_bulk(struct zone *zone, unsigned int order, + unsigned long count, struct list_head *list, + int migratetype) +{ + int i; + + spin_lock(&zone->lock); + for (i = 0; i < count; ++i) { + struct page *page = __rmqueue(zone, order, migratetype); + if (unlikely(page == NULL)) + break; + + /* + * Split buddy pages returned by expand() are received here + * in physical page order. The page is added to the callers and + * list and the list head then moves forward. From the callers + * perspective, the linked list is ordered by page number in + * some conditions. This is useful for IO devices that can + * merge IO requests if the physical pages are ordered + * properly. + */ + list_add(&page->lru, list); + set_page_private(page, migratetype); + list = &page->lru; + } + spin_unlock(&zone->lock); + return i; +} + +#ifdef CONFIG_NUMA +/* + * Called from the vmstat counter updater to drain pagesets of this + * currently executing processor on remote nodes after they have + * expired. + * + * Note that this function must be called with the thread pinned to + * a single processor. + */ +void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp) +{ + unsigned long flags; + int to_drain; + + local_irq_save(flags); + if (pcp->count >= pcp->batch) + to_drain = pcp->batch; + else + to_drain = pcp->count; + free_pages_bulk(zone, to_drain, &pcp->list, 0); + pcp->count -= to_drain; + local_irq_restore(flags); +} +#endif + +/* + * Drain pages of the indicated processor. + * + * The processor must either be the current processor and the + * thread pinned to the current processor or a processor that + * is not online. + */ +static void drain_pages(unsigned int cpu) +{ + unsigned long flags; + struct zone *zone; + + for_each_zone(zone) { + struct per_cpu_pageset *pset; + struct per_cpu_pages *pcp; + + if (!populated_zone(zone)) + continue; + + pset = zone_pcp(zone, cpu); + + pcp = &pset->pcp; + local_irq_save(flags); + free_pages_bulk(zone, pcp->count, &pcp->list, 0); + pcp->count = 0; + local_irq_restore(flags); + } +} + +/* + * Spill all of this CPU's per-cpu pages back into the buddy allocator. + */ +void drain_local_pages(void *arg) +{ + drain_pages(smp_processor_id()); +} + +/* + * Spill all the per-cpu pages from all CPUs back into the buddy allocator + */ +void drain_all_pages(void) +{ + on_each_cpu(drain_local_pages, NULL, 1); +} + +#ifdef CONFIG_HIBERNATION + +void mark_free_pages(struct zone *zone) +{ + unsigned long pfn, max_zone_pfn; + unsigned long flags; + int order, t; + struct list_head *curr; + + if (!zone->spanned_pages) + return; + + spin_lock_irqsave(&zone->lock, flags); + + max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; + for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) + if (pfn_valid(pfn)) { + struct page *page = pfn_to_page(pfn); + + if (!swsusp_page_is_forbidden(page)) + swsusp_unset_page_free(page); + } + + for_each_migratetype_order(order, t) { + list_for_each(curr, &zone->free_area[order].free_list[t]) { + unsigned long i; + + pfn = page_to_pfn(list_entry(curr, struct page, lru)); + for (i = 0; i < (1UL << order); i++) + swsusp_set_page_free(pfn_to_page(pfn + i)); + } + } + spin_unlock_irqrestore(&zone->lock, flags); +} +#endif /* CONFIG_PM */ + +/* + * Free a 0-order page + */ +static void free_hot_cold_page(struct page *page, int cold) +{ + struct zone *zone = page_zone(page); + struct per_cpu_pages *pcp; + unsigned long flags; + + if (PageAnon(page)) + page->mapping = NULL; + if (free_pages_check(page)) + return; + + if (!PageHighMem(page)) { + debug_check_no_locks_freed(page_address(page), PAGE_SIZE); + debug_check_no_obj_freed(page_address(page), PAGE_SIZE); + } + arch_free_page(page, 0); + kernel_map_pages(page, 1, 0); + + pcp = &zone_pcp(zone, get_cpu())->pcp; + local_irq_save(flags); + __count_vm_event(PGFREE); + if (cold) + list_add_tail(&page->lru, &pcp->list); + else + list_add(&page->lru, &pcp->list); + set_page_private(page, get_pageblock_migratetype(page)); + pcp->count++; + if (pcp->count >= pcp->high) { + free_pages_bulk(zone, pcp->batch, &pcp->list, 0); + pcp->count -= pcp->batch; + } + local_irq_restore(flags); + put_cpu(); +} + +void free_hot_page(struct page *page) +{ + free_hot_cold_page(page, 0); +} + +void free_cold_page(struct page *page) +{ + free_hot_cold_page(page, 1); +} + +/* + * split_page takes a non-compound higher-order page, and splits it into + * n (1<<order) sub-pages: page[0..n] + * Each sub-page must be freed individually. + * + * Note: this is probably too low level an operation for use in drivers. + * Please consult with lkml before using this in your driver. + */ +void split_page(struct page *page, unsigned int order) +{ + int i; + + VM_BUG_ON(PageCompound(page)); + VM_BUG_ON(!page_count(page)); + for (i = 1; i < (1 << order); i++) + set_page_refcounted(page + i); +} + +/* + * Really, prep_compound_page() should be called from __rmqueue_bulk(). But + * we cheat by calling it from here, in the order > 0 path. Saves a branch + * or two. + */ +static struct page *buffered_rmqueue(struct zone *preferred_zone, + struct zone *zone, int order, gfp_t gfp_flags) +{ + unsigned long flags; + struct page *page; + int cold = !!(gfp_flags & __GFP_COLD); + int cpu; + int migratetype = allocflags_to_migratetype(gfp_flags); + +again: + cpu = get_cpu(); + if (likely(order == 0)) { + struct per_cpu_pages *pcp; + + pcp = &zone_pcp(zone, cpu)->pcp; + local_irq_save(flags); + if (!pcp->count) { + pcp->count = rmqueue_bulk(zone, 0, + pcp->batch, &pcp->list, migratetype); + if (unlikely(!pcp->count)) + goto failed; + } + + /* Find a page of the appropriate migrate type */ + if (cold) { + list_for_each_entry_reverse(page, &pcp->list, lru) + if (page_private(page) == migratetype) + break; + } else { + list_for_each_entry(page, &pcp->list, lru) + if (page_private(page) == migratetype) + break; + } + + /* Allocate more to the pcp list if necessary */ + if (unlikely(&page->lru == &pcp->list)) { + pcp->count += rmqueue_bulk(zone, 0, + pcp->batch, &pcp->list, migratetype); + page = list_entry(pcp->list.next, struct page, lru); + } + + list_del(&page->lru); + pcp->count--; + } else { + spin_lock_irqsave(&zone->lock, flags); + page = __rmqueue(zone, order, migratetype); + spin_unlock(&zone->lock); + if (!page) + goto failed; + } + + __count_zone_vm_events(PGALLOC, zone, 1 << order); + zone_statistics(preferred_zone, zone); + local_irq_restore(flags); + put_cpu(); + + VM_BUG_ON(bad_range(zone, page)); + if (prep_new_page(page, order, gfp_flags)) + goto again; + return page; + +failed: + local_irq_restore(flags); + put_cpu(); + return NULL; +} + +#define ALLOC_NO_WATERMARKS 0x01 /* don't check watermarks at all */ +#define ALLOC_WMARK_MIN 0x02 /* use pages_min watermark */ +#define ALLOC_WMARK_LOW 0x04 /* use pages_low watermark */ +#define ALLOC_WMARK_HIGH 0x08 /* use pages_high watermark */ +#define ALLOC_HARDER 0x10 /* try to alloc harder */ +#define ALLOC_HIGH 0x20 /* __GFP_HIGH set */ +#define ALLOC_CPUSET 0x40 /* check for correct cpuset */ + +#ifdef CONFIG_FAIL_PAGE_ALLOC + +static struct fail_page_alloc_attr { + struct fault_attr attr; + + u32 ignore_gfp_highmem; + u32 ignore_gfp_wait; + u32 min_order; + +#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS + + struct dentry *ignore_gfp_highmem_file; + struct dentry *ignore_gfp_wait_file; + struct dentry *min_order_file; + +#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */ + +} fail_page_alloc = { + .attr = FAULT_ATTR_INITIALIZER, + .ignore_gfp_wait = 1, + .ignore_gfp_highmem = 1, + .min_order = 1, +}; + +static int __init setup_fail_page_alloc(char *str) +{ + return setup_fault_attr(&fail_page_alloc.attr, str); +} +__setup("fail_page_alloc=", setup_fail_page_alloc); + +static int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) +{ + if (order < fail_page_alloc.min_order) + return 0; + if (gfp_mask & __GFP_NOFAIL) + return 0; + if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM)) + return 0; + if (fail_page_alloc.ignore_gfp_wait && (gfp_mask & __GFP_WAIT)) + return 0; + + return should_fail(&fail_page_alloc.attr, 1 << order); +} + +#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS + +static int __init fail_page_alloc_debugfs(void) +{ + mode_t mode = S_IFREG | S_IRUSR | S_IWUSR; + struct dentry *dir; + int err; + + err = init_fault_attr_dentries(&fail_page_alloc.attr, + "fail_page_alloc"); + if (err) + return err; + dir = fail_page_alloc.attr.dentries.dir; + + fail_page_alloc.ignore_gfp_wait_file = + debugfs_create_bool("ignore-gfp-wait", mode, dir, + &fail_page_alloc.ignore_gfp_wait); + + fail_page_alloc.ignore_gfp_highmem_file = + debugfs_create_bool("ignore-gfp-highmem", mode, dir, + &fail_page_alloc.ignore_gfp_highmem); + fail_page_alloc.min_order_file = + debugfs_create_u32("min-order", mode, dir, + &fail_page_alloc.min_order); + + if (!fail_page_alloc.ignore_gfp_wait_file || + !fail_page_alloc.ignore_gfp_highmem_file || + !fail_page_alloc.min_order_file) { + err = -ENOMEM; + debugfs_remove(fail_page_alloc.ignore_gfp_wait_file); + debugfs_remove(fail_page_alloc.ignore_gfp_highmem_file); + debugfs_remove(fail_page_alloc.min_order_file); + cleanup_fault_attr_dentries(&fail_page_alloc.attr); + } + + return err; +} + +late_initcall(fail_page_alloc_debugfs); + +#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */ + +#else /* CONFIG_FAIL_PAGE_ALLOC */ + +static inline int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) +{ + return 0; +} + +#endif /* CONFIG_FAIL_PAGE_ALLOC */ + +/* + * Return 1 if free pages are above 'mark'. This takes into account the order + * of the allocation. + */ +int zone_watermark_ok(struct zone *z, int order, unsigned long mark, + int classzone_idx, int alloc_flags) +{ + /* free_pages my go negative - that's OK */ + long min = mark; + long free_pages = zone_page_state(z, NR_FREE_PAGES) - (1 << order) + 1; + int o; + + if (alloc_flags & ALLOC_HIGH) + min -= min / 2; + if (alloc_flags & ALLOC_HARDER) + min -= min / 4; + + if (free_pages <= min + z->lowmem_reserve[classzone_idx]) + return 0; + for (o = 0; o < order; o++) { + /* At the next order, this order's pages become unavailable */ + free_pages -= z->free_area[o].nr_free << o; + + /* Require fewer higher order pages to be free */ + min >>= 1; + + if (free_pages <= min) + return 0; + } + return 1; +} + +#ifdef CONFIG_NUMA +/* + * zlc_setup - Setup for "zonelist cache". Uses cached zone data to + * skip over zones that are not allowed by the cpuset, or that have + * been recently (in last second) found to be nearly full. See further + * comments in mmzone.h. Reduces cache footprint of zonelist scans + * that have to skip over a lot of full or unallowed zones. + * + * If the zonelist cache is present in the passed in zonelist, then + * returns a pointer to the allowed node mask (either the current + * tasks mems_allowed, or node_states[N_HIGH_MEMORY].) + * + * If the zonelist cache is not available for this zonelist, does + * nothing and returns NULL. + * + * If the fullzones BITMAP in the zonelist cache is stale (more than + * a second since last zap'd) then we zap it out (clear its bits.) + * + * We hold off even calling zlc_setup, until after we've checked the + * first zone in the zonelist, on the theory that most allocations will + * be satisfied from that first zone, so best to examine that zone as + * quickly as we can. + */ +static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags) +{ + struct zonelist_cache *zlc; /* cached zonelist speedup info */ + nodemask_t *allowednodes; /* zonelist_cache approximation */ + + zlc = zonelist->zlcache_ptr; + if (!zlc) + return NULL; + + if (time_after(jiffies, zlc->last_full_zap + HZ)) { + bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST); + zlc->last_full_zap = jiffies; + } + + allowednodes = !in_interrupt() && (alloc_flags & ALLOC_CPUSET) ? + &cpuset_current_mems_allowed : + &node_states[N_HIGH_MEMORY]; + return allowednodes; +} + +/* + * Given 'z' scanning a zonelist, run a couple of quick checks to see + * if it is worth looking at further for free memory: + * 1) Check that the zone isn't thought to be full (doesn't have its + * bit set in the zonelist_cache fullzones BITMAP). + * 2) Check that the zones node (obtained from the zonelist_cache + * z_to_n[] mapping) is allowed in the passed in allowednodes mask. + * Return true (non-zero) if zone is worth looking at further, or + * else return false (zero) if it is not. + * + * This check -ignores- the distinction between various watermarks, + * such as GFP_HIGH, GFP_ATOMIC, PF_MEMALLOC, ... If a zone is + * found to be full for any variation of these watermarks, it will + * be considered full for up to one second by all requests, unless + * we are so low on memory on all allowed nodes that we are forced + * into the second scan of the zonelist. + * + * In the second scan we ignore this zonelist cache and exactly + * apply the watermarks to all zones, even it is slower to do so. + * We are low on memory in the second scan, and should leave no stone + * unturned looking for a free page. + */ +static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z, + nodemask_t *allowednodes) +{ + struct zonelist_cache *zlc; /* cached zonelist speedup info */ + int i; /* index of *z in zonelist zones */ + int n; /* node that zone *z is on */ + + zlc = zonelist->zlcache_ptr; + if (!zlc) + return 1; + + i = z - zonelist->_zonerefs; + n = zlc->z_to_n[i]; + + /* This zone is worth trying if it is allowed but not full */ + return node_isset(n, *allowednodes) && !test_bit(i, zlc->fullzones); +} + +/* + * Given 'z' scanning a zonelist, set the corresponding bit in + * zlc->fullzones, so that subsequent attempts to allocate a page + * from that zone don't waste time re-examining it. + */ +static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z) +{ + struct zonelist_cache *zlc; /* cached zonelist speedup info */ + int i; /* index of *z in zonelist zones */ + + zlc = zonelist->zlcache_ptr; + if (!zlc) + return; + + i = z - zonelist->_zonerefs; + + set_bit(i, zlc->fullzones); +} + +#else /* CONFIG_NUMA */ + +static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags) +{ + return NULL; +} + +static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z, + nodemask_t *allowednodes) +{ + return 1; +} + +static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z) +{ +} +#endif /* CONFIG_NUMA */ + +/* + * get_page_from_freelist goes through the zonelist trying to allocate + * a page. + */ +static struct page * +get_page_from_freelist(gfp_t gfp_mask, nodemask_t *nodemask, unsigned int order, + struct zonelist *zonelist, int high_zoneidx, int alloc_flags) +{ + struct zoneref *z; + struct page *page = NULL; + int classzone_idx; + struct zone *zone, *preferred_zone; + nodemask_t *allowednodes = NULL;/* zonelist_cache approximation */ + int zlc_active = 0; /* set if using zonelist_cache */ + int did_zlc_setup = 0; /* just call zlc_setup() one time */ + + (void)first_zones_zonelist(zonelist, high_zoneidx, nodemask, + &preferred_zone); + if (!preferred_zone) + return NULL; + + classzone_idx = zone_idx(preferred_zone); + +zonelist_scan: + /* + * Scan zonelist, looking for a zone with enough free. + * See also cpuset_zone_allowed() comment in kernel/cpuset.c. + */ + for_each_zone_zonelist_nodemask(zone, z, zonelist, + high_zoneidx, nodemask) { + if (NUMA_BUILD && zlc_active && + !zlc_zone_worth_trying(zonelist, z, allowednodes)) + continue; + if ((alloc_flags & ALLOC_CPUSET) && + !cpuset_zone_allowed_softwall(zone, gfp_mask)) + goto try_next_zone; + + if (!(alloc_flags & ALLOC_NO_WATERMARKS)) { + unsigned long mark; + if (alloc_flags & ALLOC_WMARK_MIN) + mark = zone->pages_min; + else if (alloc_flags & ALLOC_WMARK_LOW) + mark = zone->pages_low; + else + mark = zone->pages_high; + if (!zone_watermark_ok(zone, order, mark, + classzone_idx, alloc_flags)) { + if (!zone_reclaim_mode || + !zone_reclaim(zone, gfp_mask, order)) + goto this_zone_full; + } + } + + page = buffered_rmqueue(preferred_zone, zone, order, gfp_mask); + if (page) + break; +this_zone_full: + if (NUMA_BUILD) + zlc_mark_zone_full(zonelist, z); +try_next_zone: + if (NUMA_BUILD && !did_zlc_setup) { + /* we do zlc_setup after the first zone is tried */ + allowednodes = zlc_setup(zonelist, alloc_flags); + zlc_active = 1; + did_zlc_setup = 1; + } + } + + if (unlikely(NUMA_BUILD && page == NULL && zlc_active)) { + /* Disable zlc cache for second zonelist scan */ + zlc_active = 0; + goto zonelist_scan; + } + return page; +} + +/* + * This is the 'heart' of the zoned buddy allocator. + */ +struct page * +__alloc_pages_internal(gfp_t gfp_mask, unsigned int order, + struct zonelist *zonelist, nodemask_t *nodemask) +{ + const gfp_t wait = gfp_mask & __GFP_WAIT; + enum zone_type high_zoneidx = gfp_zone(gfp_mask); + struct zoneref *z; + struct zone *zone; + struct page *page; + struct reclaim_state reclaim_state; + struct task_struct *p = current; + int do_retry; + int alloc_flags; + unsigned long did_some_progress; + unsigned long pages_reclaimed = 0; + + might_sleep_if(wait); + + if (should_fail_alloc_page(gfp_mask, order)) + return NULL; + +restart: + z = zonelist->_zonerefs; /* the list of zones suitable for gfp_mask */ + + if (unlikely(!z->zone)) { + /* + * Happens if we have an empty zonelist as a result of + * GFP_THISNODE being used on a memoryless node + */ + return NULL; + } + + page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order, + zonelist, high_zoneidx, ALLOC_WMARK_LOW|ALLOC_CPUSET); + if (page) + goto got_pg; + + /* + * GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and + * __GFP_NOWARN set) should not cause reclaim since the subsystem + * (f.e. slab) using GFP_THISNODE may choose to trigger reclaim + * using a larger set of nodes after it has established that the + * allowed per node queues are empty and that nodes are + * over allocated. + */ + if (NUMA_BUILD && (gfp_mask & GFP_THISNODE) == GFP_THISNODE) + goto nopage; + + for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) + wakeup_kswapd(zone, order); + + /* + * OK, we're below the kswapd watermark and have kicked background + * reclaim. Now things get more complex, so set up alloc_flags according + * to how we want to proceed. + * + * The caller may dip into page reserves a bit more if the caller + * cannot run direct reclaim, or if the caller has realtime scheduling + * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will + * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH). + */ + alloc_flags = ALLOC_WMARK_MIN; + if ((unlikely(rt_task(p)) && !in_interrupt()) || !wait) + alloc_flags |= ALLOC_HARDER; + if (gfp_mask & __GFP_HIGH) + alloc_flags |= ALLOC_HIGH; + if (wait) + alloc_flags |= ALLOC_CPUSET; + + /* + * Go through the zonelist again. Let __GFP_HIGH and allocations + * coming from realtime tasks go deeper into reserves. + * + * This is the last chance, in general, before the goto nopage. + * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc. + * See also cpuset_zone_allowed() comment in kernel/cpuset.c. + */ + page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist, + high_zoneidx, alloc_flags); + if (page) + goto got_pg; + + /* This allocation should allow future memory freeing. */ + +rebalance: + if (((p->flags & PF_MEMALLOC) || unlikely(test_thread_flag(TIF_MEMDIE))) + && !in_interrupt()) { + if (!(gfp_mask & __GFP_NOMEMALLOC)) { +nofail_alloc: + /* go through the zonelist yet again, ignoring mins */ + page = get_page_from_freelist(gfp_mask, nodemask, order, + zonelist, high_zoneidx, ALLOC_NO_WATERMARKS); + if (page) + goto got_pg; + if (gfp_mask & __GFP_NOFAIL) { + congestion_wait(WRITE, HZ/50); + goto nofail_alloc; + } + } + goto nopage; + } + + /* Atomic allocations - we can't balance anything */ + if (!wait) + goto nopage; + + cond_resched(); + + /* We now go into synchronous reclaim */ + cpuset_memory_pressure_bump(); + /* + * The task's cpuset might have expanded its set of allowable nodes + */ + cpuset_update_task_memory_state(); + p->flags |= PF_MEMALLOC; + reclaim_state.reclaimed_slab = 0; + p->reclaim_state = &reclaim_state; + + did_some_progress = try_to_free_pages(zonelist, order, gfp_mask); + + p->reclaim_state = NULL; + p->flags &= ~PF_MEMALLOC; + + cond_resched(); + + if (order != 0) + drain_all_pages(); + + if (likely(did_some_progress)) { + page = get_page_from_freelist(gfp_mask, nodemask, order, + zonelist, high_zoneidx, alloc_flags); + if (page) + goto got_pg; + } else if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) { + if (!try_set_zone_oom(zonelist, gfp_mask)) { + schedule_timeout_uninterruptible(1); + goto restart; + } + + /* + * Go through the zonelist yet one more time, keep + * very high watermark here, this is only to catch + * a parallel oom killing, we must fail if we're still + * under heavy pressure. + */ + page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, + order, zonelist, high_zoneidx, + ALLOC_WMARK_HIGH|ALLOC_CPUSET); + if (page) { + clear_zonelist_oom(zonelist, gfp_mask); + goto got_pg; + } + + /* The OOM killer will not help higher order allocs so fail */ + if (order > PAGE_ALLOC_COSTLY_ORDER) { + clear_zonelist_oom(zonelist, gfp_mask); + goto nopage; + } + + out_of_memory(zonelist, gfp_mask, order); + clear_zonelist_oom(zonelist, gfp_mask); + goto restart; + } + + /* + * Don't let big-order allocations loop unless the caller explicitly + * requests that. Wait for some write requests to complete then retry. + * + * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER + * means __GFP_NOFAIL, but that may not be true in other + * implementations. + * + * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is + * specified, then we retry until we no longer reclaim any pages + * (above), or we've reclaimed an order of pages at least as + * large as the allocation's order. In both cases, if the + * allocation still fails, we stop retrying. + */ + pages_reclaimed += did_some_progress; + do_retry = 0; + if (!(gfp_mask & __GFP_NORETRY)) { + if (order <= PAGE_ALLOC_COSTLY_ORDER) { + do_retry = 1; + } else { + if (gfp_mask & __GFP_REPEAT && + pages_reclaimed < (1 << order)) + do_retry = 1; + } + if (gfp_mask & __GFP_NOFAIL) + do_retry = 1; + } + if (do_retry) { + congestion_wait(WRITE, HZ/50); + goto rebalance; + } + +nopage: + if (!(gfp_mask & __GFP_NOWARN) && printk_ratelimit()) { + printk(KERN_WARNING "%s: page allocation failure." + " order:%d, mode:0x%x\n", + p->comm, order, gfp_mask); + dump_stack(); + show_mem(); + } +got_pg: + return page; +} +EXPORT_SYMBOL(__alloc_pages_internal); + +/* + * Common helper functions. + */ +unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order) +{ + struct page * page; + page = alloc_pages(gfp_mask, order); + if (!page) + return 0; + return (unsigned long) page_address(page); +} + +EXPORT_SYMBOL(__get_free_pages); + +unsigned long get_zeroed_page(gfp_t gfp_mask) +{ + struct page * page; + + /* + * get_zeroed_page() returns a 32-bit address, which cannot represent + * a highmem page + */ + VM_BUG_ON((gfp_mask & __GFP_HIGHMEM) != 0); + + page = alloc_pages(gfp_mask | __GFP_ZERO, 0); + if (page) + return (unsigned long) page_address(page); + return 0; +} + +EXPORT_SYMBOL(get_zeroed_page); + +void __pagevec_free(struct pagevec *pvec) +{ + int i = pagevec_count(pvec); + + while (--i >= 0) + free_hot_cold_page(pvec->pages[i], pvec->cold); +} + +void __free_pages(struct page *page, unsigned int order) +{ + if (put_page_testzero(page)) { + if (order == 0) + free_hot_page(page); + else + __free_pages_ok(page, order); + } +} + +EXPORT_SYMBOL(__free_pages); + +void free_pages(unsigned long addr, unsigned int order) +{ + if (addr != 0) { + VM_BUG_ON(!virt_addr_valid((void *)addr)); + __free_pages(virt_to_page((void *)addr), order); + } +} + +EXPORT_SYMBOL(free_pages); + +/** + * alloc_pages_exact - allocate an exact number physically-contiguous pages. + * @size: the number of bytes to allocate + * @gfp_mask: GFP flags for the allocation + * + * This function is similar to alloc_pages(), except that it allocates the + * minimum number of pages to satisfy the request. alloc_pages() can only + * allocate memory in power-of-two pages. + * + * This function is also limited by MAX_ORDER. + * + * Memory allocated by this function must be released by free_pages_exact(). + */ +void *alloc_pages_exact(size_t size, gfp_t gfp_mask) +{ + unsigned int order = get_order(size); + unsigned long addr; + + addr = __get_free_pages(gfp_mask, order); + if (addr) { + unsigned long alloc_end = addr + (PAGE_SIZE << order); + unsigned long used = addr + PAGE_ALIGN(size); + + split_page(virt_to_page(addr), order); + while (used < alloc_end) { + free_page(used); + used += PAGE_SIZE; + } + } + + return (void *)addr; +} +EXPORT_SYMBOL(alloc_pages_exact); + +/** + * free_pages_exact - release memory allocated via alloc_pages_exact() + * @virt: the value returned by alloc_pages_exact. + * @size: size of allocation, same value as passed to alloc_pages_exact(). + * + * Release the memory allocated by a previous call to alloc_pages_exact. + */ +void free_pages_exact(void *virt, size_t size) +{ + unsigned long addr = (unsigned long)virt; + unsigned long end = addr + PAGE_ALIGN(size); + + while (addr < end) { + free_page(addr); + addr += PAGE_SIZE; + } +} +EXPORT_SYMBOL(free_pages_exact); + +static unsigned int nr_free_zone_pages(int offset) +{ + struct zoneref *z; + struct zone *zone; + + /* Just pick one node, since fallback list is circular */ + unsigned int sum = 0; + + struct zonelist *zonelist = node_zonelist(numa_node_id(), GFP_KERNEL); + + for_each_zone_zonelist(zone, z, zonelist, offset) { + unsigned long size = zone->present_pages; + unsigned long high = zone->pages_high; + if (size > high) + sum += size - high; + } + + return sum; +} + +/* + * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL + */ +unsigned int nr_free_buffer_pages(void) +{ + return nr_free_zone_pages(gfp_zone(GFP_USER)); +} +EXPORT_SYMBOL_GPL(nr_free_buffer_pages); + +/* + * Amount of free RAM allocatable within all zones + */ +unsigned int nr_free_pagecache_pages(void) +{ + return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE)); +} + +static inline void show_node(struct zone *zone) +{ + if (NUMA_BUILD) + printk("Node %d ", zone_to_nid(zone)); +} + +void si_meminfo(struct sysinfo *val) +{ + val->totalram = totalram_pages; + val->sharedram = 0; + val->freeram = global_page_state(NR_FREE_PAGES); + val->bufferram = nr_blockdev_pages(); + val->totalhigh = totalhigh_pages; + val->freehigh = nr_free_highpages(); + val->mem_unit = PAGE_SIZE; +} + +EXPORT_SYMBOL(si_meminfo); + +#ifdef CONFIG_NUMA +void si_meminfo_node(struct sysinfo *val, int nid) +{ + pg_data_t *pgdat = NODE_DATA(nid); + + val->totalram = pgdat->node_present_pages; + val->freeram = node_page_state(nid, NR_FREE_PAGES); +#ifdef CONFIG_HIGHMEM + val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].present_pages; + val->freehigh = zone_page_state(&pgdat->node_zones[ZONE_HIGHMEM], + NR_FREE_PAGES); +#else + val->totalhigh = 0; + val->freehigh = 0; +#endif + val->mem_unit = PAGE_SIZE; +} +#endif + +#define K(x) ((x) << (PAGE_SHIFT-10)) + +/* + * Show free area list (used inside shift_scroll-lock stuff) + * We also calculate the percentage fragmentation. We do this by counting the + * memory on each free list with the exception of the first item on the list. + */ +void show_free_areas(void) +{ + int cpu; + struct zone *zone; + + for_each_zone(zone) { + if (!populated_zone(zone)) + continue; + + show_node(zone); + printk("%s per-cpu:\n", zone->name); + + for_each_online_cpu(cpu) { + struct per_cpu_pageset *pageset; + + pageset = zone_pcp(zone, cpu); + + printk("CPU %4d: hi:%5d, btch:%4d usd:%4d\n", + cpu, pageset->pcp.high, + pageset->pcp.batch, pageset->pcp.count); + } + } + + printk("Active_anon:%lu active_file:%lu inactive_anon:%lu\n" + " inactive_file:%lu" +//TODO: check/adjust line lengths +#ifdef CONFIG_UNEVICTABLE_LRU + " unevictable:%lu" +#endif + " dirty:%lu writeback:%lu unstable:%lu\n" + " free:%lu slab:%lu mapped:%lu pagetables:%lu bounce:%lu\n", + global_page_state(NR_ACTIVE_ANON), + global_page_state(NR_ACTIVE_FILE), + global_page_state(NR_INACTIVE_ANON), + global_page_state(NR_INACTIVE_FILE), +#ifdef CONFIG_UNEVICTABLE_LRU + global_page_state(NR_UNEVICTABLE), +#endif + global_page_state(NR_FILE_DIRTY), + global_page_state(NR_WRITEBACK), + global_page_state(NR_UNSTABLE_NFS), + global_page_state(NR_FREE_PAGES), + global_page_state(NR_SLAB_RECLAIMABLE) + + global_page_state(NR_SLAB_UNRECLAIMABLE), + global_page_state(NR_FILE_MAPPED), + global_page_state(NR_PAGETABLE), + global_page_state(NR_BOUNCE)); + + for_each_zone(zone) { + int i; + + if (!populated_zone(zone)) + continue; + + show_node(zone); + printk("%s" + " free:%lukB" + " min:%lukB" + " low:%lukB" + " high:%lukB" + " active_anon:%lukB" + " inactive_anon:%lukB" + " active_file:%lukB" + " inactive_file:%lukB" +#ifdef CONFIG_UNEVICTABLE_LRU + " unevictable:%lukB" +#endif + " present:%lukB" + " pages_scanned:%lu" + " all_unreclaimable? %s" + "\n", + zone->name, + K(zone_page_state(zone, NR_FREE_PAGES)), + K(zone->pages_min), + K(zone->pages_low), + K(zone->pages_high), + K(zone_page_state(zone, NR_ACTIVE_ANON)), + K(zone_page_state(zone, NR_INACTIVE_ANON)), + K(zone_page_state(zone, NR_ACTIVE_FILE)), + K(zone_page_state(zone, NR_INACTIVE_FILE)), +#ifdef CONFIG_UNEVICTABLE_LRU + K(zone_page_state(zone, NR_UNEVICTABLE)), +#endif + K(zone->present_pages), + zone->pages_scanned, + (zone_is_all_unreclaimable(zone) ? "yes" : "no") + ); + printk("lowmem_reserve[]:"); + for (i = 0; i < MAX_NR_ZONES; i++) + printk(" %lu", zone->lowmem_reserve[i]); + printk("\n"); + } + + for_each_zone(zone) { + unsigned long nr[MAX_ORDER], flags, order, total = 0; + + if (!populated_zone(zone)) + continue; + + show_node(zone); + printk("%s: ", zone->name); + + spin_lock_irqsave(&zone->lock, flags); + for (order = 0; order < MAX_ORDER; order++) { + nr[order] = zone->free_area[order].nr_free; + total += nr[order] << order; + } + spin_unlock_irqrestore(&zone->lock, flags); + for (order = 0; order < MAX_ORDER; order++) + printk("%lu*%lukB ", nr[order], K(1UL) << order); + printk("= %lukB\n", K(total)); + } + + printk("%ld total pagecache pages\n", global_page_state(NR_FILE_PAGES)); + + show_swap_cache_info(); +} + +static void zoneref_set_zone(struct zone *zone, struct zoneref *zoneref) +{ + zoneref->zone = zone; + zoneref->zone_idx = zone_idx(zone); +} + +/* + * Builds allocation fallback zone lists. + * + * Add all populated zones of a node to the zonelist. + */ +static int build_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist, + int nr_zones, enum zone_type zone_type) +{ + struct zone *zone; + + BUG_ON(zone_type >= MAX_NR_ZONES); + zone_type++; + + do { + zone_type--; + zone = pgdat->node_zones + zone_type; + if (populated_zone(zone)) { + zoneref_set_zone(zone, + &zonelist->_zonerefs[nr_zones++]); + check_highest_zone(zone_type); + } + + } while (zone_type); + return nr_zones; +} + + +/* + * zonelist_order: + * 0 = automatic detection of better ordering. + * 1 = order by ([node] distance, -zonetype) + * 2 = order by (-zonetype, [node] distance) + * + * If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create + * the same zonelist. So only NUMA can configure this param. + */ +#define ZONELIST_ORDER_DEFAULT 0 +#define ZONELIST_ORDER_NODE 1 +#define ZONELIST_ORDER_ZONE 2 + +/* zonelist order in the kernel. + * set_zonelist_order() will set this to NODE or ZONE. + */ +static int current_zonelist_order = ZONELIST_ORDER_DEFAULT; +static char zonelist_order_name[3][8] = {"Default", "Node", "Zone"}; + + +#ifdef CONFIG_NUMA +/* The value user specified ....changed by config */ +static int user_zonelist_order = ZONELIST_ORDER_DEFAULT; +/* string for sysctl */ +#define NUMA_ZONELIST_ORDER_LEN 16 +char numa_zonelist_order[16] = "default"; + +/* + * interface for configure zonelist ordering. + * command line option "numa_zonelist_order" + * = "[dD]efault - default, automatic configuration. + * = "[nN]ode - order by node locality, then by zone within node + * = "[zZ]one - order by zone, then by locality within zone + */ + +static int __parse_numa_zonelist_order(char *s) +{ + if (*s == 'd' || *s == 'D') { + user_zonelist_order = ZONELIST_ORDER_DEFAULT; + } else if (*s == 'n' || *s == 'N') { + user_zonelist_order = ZONELIST_ORDER_NODE; + } else if (*s == 'z' || *s == 'Z') { + user_zonelist_order = ZONELIST_ORDER_ZONE; + } else { + printk(KERN_WARNING + "Ignoring invalid numa_zonelist_order value: " + "%s\n", s); + return -EINVAL; + } + return 0; +} + +static __init int setup_numa_zonelist_order(char *s) +{ + if (s) + return __parse_numa_zonelist_order(s); + return 0; +} +early_param("numa_zonelist_order", setup_numa_zonelist_order); + +/* + * sysctl handler for numa_zonelist_order + */ +int numa_zonelist_order_handler(ctl_table *table, int write, + struct file *file, void __user *buffer, size_t *length, + loff_t *ppos) +{ + char saved_string[NUMA_ZONELIST_ORDER_LEN]; + int ret; + + if (write) + strncpy(saved_string, (char*)table->data, + NUMA_ZONELIST_ORDER_LEN); + ret = proc_dostring(table, write, file, buffer, length, ppos); + if (ret) + return ret; + if (write) { + int oldval = user_zonelist_order; + if (__parse_numa_zonelist_order((char*)table->data)) { + /* + * bogus value. restore saved string + */ + strncpy((char*)table->data, saved_string, + NUMA_ZONELIST_ORDER_LEN); + user_zonelist_order = oldval; + } else if (oldval != user_zonelist_order) + build_all_zonelists(); + } + return 0; +} + + +#define MAX_NODE_LOAD (num_online_nodes()) +static int node_load[MAX_NUMNODES]; + +/** + * find_next_best_node - find the next node that should appear in a given node's fallback list + * @node: node whose fallback list we're appending + * @used_node_mask: nodemask_t of already used nodes + * + * We use a number of factors to determine which is the next node that should + * appear on a given node's fallback list. The node should not have appeared + * already in @node's fallback list, and it should be the next closest node + * according to the distance array (which contains arbitrary distance values + * from each node to each node in the system), and should also prefer nodes + * with no CPUs, since presumably they'll have very little allocation pressure + * on them otherwise. + * It returns -1 if no node is found. + */ +static int find_next_best_node(int node, nodemask_t *used_node_mask) +{ + int n, val; + int min_val = INT_MAX; + int best_node = -1; + node_to_cpumask_ptr(tmp, 0); + + /* Use the local node if we haven't already */ + if (!node_isset(node, *used_node_mask)) { + node_set(node, *used_node_mask); + return node; + } + + for_each_node_state(n, N_HIGH_MEMORY) { + + /* Don't want a node to appear more than once */ + if (node_isset(n, *used_node_mask)) + continue; + + /* Use the distance array to find the distance */ + val = node_distance(node, n); + + /* Penalize nodes under us ("prefer the next node") */ + val += (n < node); + + /* Give preference to headless and unused nodes */ + node_to_cpumask_ptr_next(tmp, n); + if (!cpus_empty(*tmp)) + val += PENALTY_FOR_NODE_WITH_CPUS; + + /* Slight preference for less loaded node */ + val *= (MAX_NODE_LOAD*MAX_NUMNODES); + val += node_load[n]; + + if (val < min_val) { + min_val = val; + best_node = n; + } + } + + if (best_node >= 0) + node_set(best_node, *used_node_mask); + + return best_node; +} + + +/* + * Build zonelists ordered by node and zones within node. + * This results in maximum locality--normal zone overflows into local + * DMA zone, if any--but risks exhausting DMA zone. + */ +static void build_zonelists_in_node_order(pg_data_t *pgdat, int node) +{ + int j; + struct zonelist *zonelist; + + zonelist = &pgdat->node_zonelists[0]; + for (j = 0; zonelist->_zonerefs[j].zone != NULL; j++) + ; + j = build_zonelists_node(NODE_DATA(node), zonelist, j, + MAX_NR_ZONES - 1); + zonelist->_zonerefs[j].zone = NULL; + zonelist->_zonerefs[j].zone_idx = 0; +} + +/* + * Build gfp_thisnode zonelists + */ +static void build_thisnode_zonelists(pg_data_t *pgdat) +{ + int j; + struct zonelist *zonelist; + + zonelist = &pgdat->node_zonelists[1]; + j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1); + zonelist->_zonerefs[j].zone = NULL; + zonelist->_zonerefs[j].zone_idx = 0; +} + +/* + * Build zonelists ordered by zone and nodes within zones. + * This results in conserving DMA zone[s] until all Normal memory is + * exhausted, but results in overflowing to remote node while memory + * may still exist in local DMA zone. + */ +static int node_order[MAX_NUMNODES]; + +static void build_zonelists_in_zone_order(pg_data_t *pgdat, int nr_nodes) +{ + int pos, j, node; + int zone_type; /* needs to be signed */ + struct zone *z; + struct zonelist *zonelist; + + zonelist = &pgdat->node_zonelists[0]; + pos = 0; + for (zone_type = MAX_NR_ZONES - 1; zone_type >= 0; zone_type--) { + for (j = 0; j < nr_nodes; j++) { + node = node_order[j]; + z = &NODE_DATA(node)->node_zones[zone_type]; + if (populated_zone(z)) { + zoneref_set_zone(z, + &zonelist->_zonerefs[pos++]); + check_highest_zone(zone_type); + } + } + } + zonelist->_zonerefs[pos].zone = NULL; + zonelist->_zonerefs[pos].zone_idx = 0; +} + +static int default_zonelist_order(void) +{ + int nid, zone_type; + unsigned long low_kmem_size,total_size; + struct zone *z; + int average_size; + /* + * ZONE_DMA and ZONE_DMA32 can be very small area in the sytem. + * If they are really small and used heavily, the system can fall + * into OOM very easily. + * This function detect ZONE_DMA/DMA32 size and confgigures zone order. + */ + /* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */ + low_kmem_size = 0; + total_size = 0; + for_each_online_node(nid) { + for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) { + z = &NODE_DATA(nid)->node_zones[zone_type]; + if (populated_zone(z)) { + if (zone_type < ZONE_NORMAL) + low_kmem_size += z->present_pages; + total_size += z->present_pages; + } + } + } + if (!low_kmem_size || /* there are no DMA area. */ + low_kmem_size > total_size/2) /* DMA/DMA32 is big. */ + return ZONELIST_ORDER_NODE; + /* + * look into each node's config. + * If there is a node whose DMA/DMA32 memory is very big area on + * local memory, NODE_ORDER may be suitable. + */ + average_size = total_size / + (nodes_weight(node_states[N_HIGH_MEMORY]) + 1); + for_each_online_node(nid) { + low_kmem_size = 0; + total_size = 0; + for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) { + z = &NODE_DATA(nid)->node_zones[zone_type]; + if (populated_zone(z)) { + if (zone_type < ZONE_NORMAL) + low_kmem_size += z->present_pages; + total_size += z->present_pages; + } + } + if (low_kmem_size && + total_size > average_size && /* ignore small node */ + low_kmem_size > total_size * 70/100) + return ZONELIST_ORDER_NODE; + } + return ZONELIST_ORDER_ZONE; +} + +static void set_zonelist_order(void) +{ + if (user_zonelist_order == ZONELIST_ORDER_DEFAULT) + current_zonelist_order = default_zonelist_order(); + else + current_zonelist_order = user_zonelist_order; +} + +static void build_zonelists(pg_data_t *pgdat) +{ + int j, node, load; + enum zone_type i; + nodemask_t used_mask; + int local_node, prev_node; + struct zonelist *zonelist; + int order = current_zonelist_order; + + /* initialize zonelists */ + for (i = 0; i < MAX_ZONELISTS; i++) { + zonelist = pgdat->node_zonelists + i; + zonelist->_zonerefs[0].zone = NULL; + zonelist->_zonerefs[0].zone_idx = 0; + } + + /* NUMA-aware ordering of nodes */ + local_node = pgdat->node_id; + load = num_online_nodes(); + prev_node = local_node; + nodes_clear(used_mask); + + memset(node_load, 0, sizeof(node_load)); + memset(node_order, 0, sizeof(node_order)); + j = 0; + + while ((node = find_next_best_node(local_node, &used_mask)) >= 0) { + int distance = node_distance(local_node, node); + + /* + * If another node is sufficiently far away then it is better + * to reclaim pages in a zone before going off node. + */ + if (distance > RECLAIM_DISTANCE) + zone_reclaim_mode = 1; + + /* + * We don't want to pressure a particular node. + * So adding penalty to the first node in same + * distance group to make it round-robin. + */ + if (distance != node_distance(local_node, prev_node)) + node_load[node] = load; + + prev_node = node; + load--; + if (order == ZONELIST_ORDER_NODE) + build_zonelists_in_node_order(pgdat, node); + else + node_order[j++] = node; /* remember order */ + } + + if (order == ZONELIST_ORDER_ZONE) { + /* calculate node order -- i.e., DMA last! */ + build_zonelists_in_zone_order(pgdat, j); + } + + build_thisnode_zonelists(pgdat); +} + +/* Construct the zonelist performance cache - see further mmzone.h */ +static void build_zonelist_cache(pg_data_t *pgdat) +{ + struct zonelist *zonelist; + struct zonelist_cache *zlc; + struct zoneref *z; + + zonelist = &pgdat->node_zonelists[0]; + zonelist->zlcache_ptr = zlc = &zonelist->zlcache; + bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST); + for (z = zonelist->_zonerefs; z->zone; z++) + zlc->z_to_n[z - zonelist->_zonerefs] = zonelist_node_idx(z); +} + + +#else /* CONFIG_NUMA */ + +static void set_zonelist_order(void) +{ + current_zonelist_order = ZONELIST_ORDER_ZONE; +} + +static void build_zonelists(pg_data_t *pgdat) +{ + int node, local_node; + enum zone_type j; + struct zonelist *zonelist; + + local_node = pgdat->node_id; + + zonelist = &pgdat->node_zonelists[0]; + j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1); + + /* + * Now we build the zonelist so that it contains the zones + * of all the other nodes. + * We don't want to pressure a particular node, so when + * building the zones for node N, we make sure that the + * zones coming right after the local ones are those from + * node N+1 (modulo N) + */ + for (node = local_node + 1; node < MAX_NUMNODES; node++) { + if (!node_online(node)) + continue; + j = build_zonelists_node(NODE_DATA(node), zonelist, j, + MAX_NR_ZONES - 1); + } + for (node = 0; node < local_node; node++) { + if (!node_online(node)) + continue; + j = build_zonelists_node(NODE_DATA(node), zonelist, j, + MAX_NR_ZONES - 1); + } + + zonelist->_zonerefs[j].zone = NULL; + zonelist->_zonerefs[j].zone_idx = 0; +} + +/* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */ +static void build_zonelist_cache(pg_data_t *pgdat) +{ + pgdat->node_zonelists[0].zlcache_ptr = NULL; +} + +#endif /* CONFIG_NUMA */ + +/* return values int ....just for stop_machine() */ +static int __build_all_zonelists(void *dummy) +{ + int nid; + + for_each_online_node(nid) { + pg_data_t *pgdat = NODE_DATA(nid); + + build_zonelists(pgdat); + build_zonelist_cache(pgdat); + } + return 0; +} + +void build_all_zonelists(void) +{ + set_zonelist_order(); + + if (system_state == SYSTEM_BOOTING) { + __build_all_zonelists(NULL); + mminit_verify_zonelist(); + cpuset_init_current_mems_allowed(); + } else { + /* we have to stop all cpus to guarantee there is no user + of zonelist */ + stop_machine(__build_all_zonelists, NULL, NULL); + /* cpuset refresh routine should be here */ + } + vm_total_pages = nr_free_pagecache_pages(); + /* + * Disable grouping by mobility if the number of pages in the + * system is too low to allow the mechanism to work. It would be + * more accurate, but expensive to check per-zone. This check is + * made on memory-hotadd so a system can start with mobility + * disabled and enable it later + */ + if (vm_total_pages < (pageblock_nr_pages * MIGRATE_TYPES)) + page_group_by_mobility_disabled = 1; + else + page_group_by_mobility_disabled = 0; + + printk("Built %i zonelists in %s order, mobility grouping %s. " + "Total pages: %ld\n", + num_online_nodes(), + zonelist_order_name[current_zonelist_order], + page_group_by_mobility_disabled ? "off" : "on", + vm_total_pages); +#ifdef CONFIG_NUMA + printk("Policy zone: %s\n", zone_names[policy_zone]); +#endif +} + +/* + * Helper functions to size the waitqueue hash table. + * Essentially these want to choose hash table sizes sufficiently + * large so that collisions trying to wait on pages are rare. + * But in fact, the number of active page waitqueues on typical + * systems is ridiculously low, less than 200. So this is even + * conservative, even though it seems large. + * + * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to + * waitqueues, i.e. the size of the waitq table given the number of pages. + */ +#define PAGES_PER_WAITQUEUE 256 + +#ifndef CONFIG_MEMORY_HOTPLUG +static inline unsigned long wait_table_hash_nr_entries(unsigned long pages) +{ + unsigned long size = 1; + + pages /= PAGES_PER_WAITQUEUE; + + while (size < pages) + size <<= 1; + + /* + * Once we have dozens or even hundreds of threads sleeping + * on IO we've got bigger problems than wait queue collision. + * Limit the size of the wait table to a reasonable size. + */ + size = min(size, 4096UL); + + return max(size, 4UL); +} +#else +/* + * A zone's size might be changed by hot-add, so it is not possible to determine + * a suitable size for its wait_table. So we use the maximum size now. + * + * The max wait table size = 4096 x sizeof(wait_queue_head_t). ie: + * + * i386 (preemption config) : 4096 x 16 = 64Kbyte. + * ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte. + * ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte. + * + * The maximum entries are prepared when a zone's memory is (512K + 256) pages + * or more by the traditional way. (See above). It equals: + * + * i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte. + * ia64(16K page size) : = ( 8G + 4M)byte. + * powerpc (64K page size) : = (32G +16M)byte. + */ +static inline unsigned long wait_table_hash_nr_entries(unsigned long pages) +{ + return 4096UL; +} +#endif + +/* + * This is an integer logarithm so that shifts can be used later + * to extract the more random high bits from the multiplicative + * hash function before the remainder is taken. + */ +static inline unsigned long wait_table_bits(unsigned long size) +{ + return ffz(~size); +} + +#define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1)) + +/* + * Mark a number of pageblocks as MIGRATE_RESERVE. The number + * of blocks reserved is based on zone->pages_min. The memory within the + * reserve will tend to store contiguous free pages. Setting min_free_kbytes + * higher will lead to a bigger reserve which will get freed as contiguous + * blocks as reclaim kicks in + */ +static void setup_zone_migrate_reserve(struct zone *zone) +{ + unsigned long start_pfn, pfn, end_pfn; + struct page *page; + unsigned long reserve, block_migratetype; + + /* Get the start pfn, end pfn and the number of blocks to reserve */ + start_pfn = zone->zone_start_pfn; + end_pfn = start_pfn + zone->spanned_pages; + reserve = roundup(zone->pages_min, pageblock_nr_pages) >> + pageblock_order; + + for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) { + if (!pfn_valid(pfn)) + continue; + page = pfn_to_page(pfn); + + /* Watch out for overlapping nodes */ + if (page_to_nid(page) != zone_to_nid(zone)) + continue; + + /* Blocks with reserved pages will never free, skip them. */ + if (PageReserved(page)) + continue; + + block_migratetype = get_pageblock_migratetype(page); + + /* If this block is reserved, account for it */ + if (reserve > 0 && block_migratetype == MIGRATE_RESERVE) { + reserve--; + continue; + } + + /* Suitable for reserving if this block is movable */ + if (reserve > 0 && block_migratetype == MIGRATE_MOVABLE) { + set_pageblock_migratetype(page, MIGRATE_RESERVE); + move_freepages_block(zone, page, MIGRATE_RESERVE); + reserve--; + continue; + } + + /* + * If the reserve is met and this is a previous reserved block, + * take it back + */ + if (block_migratetype == MIGRATE_RESERVE) { + set_pageblock_migratetype(page, MIGRATE_MOVABLE); + move_freepages_block(zone, page, MIGRATE_MOVABLE); + } + } +} + +/* + * Initially all pages are reserved - free ones are freed + * up by free_all_bootmem() once the early boot process is + * done. Non-atomic initialization, single-pass. + */ +void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, + unsigned long start_pfn, enum memmap_context context) +{ + struct page *page; + unsigned long end_pfn = start_pfn + size; + unsigned long pfn; + struct zone *z; + + z = &NODE_DATA(nid)->node_zones[zone]; + for (pfn = start_pfn; pfn < end_pfn; pfn++) { + /* + * There can be holes in boot-time mem_map[]s + * handed to this function. They do not + * exist on hotplugged memory. + */ + if (context == MEMMAP_EARLY) { + if (!early_pfn_valid(pfn)) + continue; + if (!early_pfn_in_nid(pfn, nid)) + continue; + } + page = pfn_to_page(pfn); + set_page_links(page, zone, nid, pfn); + mminit_verify_page_links(page, zone, nid, pfn); + init_page_count(page); + reset_page_mapcount(page); + SetPageReserved(page); + /* + * Mark the block movable so that blocks are reserved for + * movable at startup. This will force kernel allocations + * to reserve their blocks rather than leaking throughout + * the address space during boot when many long-lived + * kernel allocations are made. Later some blocks near + * the start are marked MIGRATE_RESERVE by + * setup_zone_migrate_reserve() + * + * bitmap is created for zone's valid pfn range. but memmap + * can be created for invalid pages (for alignment) + * check here not to call set_pageblock_migratetype() against + * pfn out of zone. + */ + if ((z->zone_start_pfn <= pfn) + && (pfn < z->zone_start_pfn + z->spanned_pages) + && !(pfn & (pageblock_nr_pages - 1))) + set_pageblock_migratetype(page, MIGRATE_MOVABLE); + + INIT_LIST_HEAD(&page->lru); +#ifdef WANT_PAGE_VIRTUAL + /* The shift won't overflow because ZONE_NORMAL is below 4G. */ + if (!is_highmem_idx(zone)) + set_page_address(page, __va(pfn << PAGE_SHIFT)); +#endif + } +} + +static void __meminit zone_init_free_lists(struct zone *zone) +{ + int order, t; + for_each_migratetype_order(order, t) { + INIT_LIST_HEAD(&zone->free_area[order].free_list[t]); + zone->free_area[order].nr_free = 0; + } +} + +#ifndef __HAVE_ARCH_MEMMAP_INIT +#define memmap_init(size, nid, zone, start_pfn) \ + memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY) +#endif + +static int zone_batchsize(struct zone *zone) +{ + int batch; + + /* + * The per-cpu-pages pools are set to around 1000th of the + * size of the zone. But no more than 1/2 of a meg. + * + * OK, so we don't know how big the cache is. So guess. + */ + batch = zone->present_pages / 1024; + if (batch * PAGE_SIZE > 512 * 1024) + batch = (512 * 1024) / PAGE_SIZE; + batch /= 4; /* We effectively *= 4 below */ + if (batch < 1) + batch = 1; + + /* + * Clamp the batch to a 2^n - 1 value. Having a power + * of 2 value was found to be more likely to have + * suboptimal cache aliasing properties in some cases. + * + * For example if 2 tasks are alternately allocating + * batches of pages, one task can end up with a lot + * of pages of one half of the possible page colors + * and the other with pages of the other colors. + */ + batch = (1 << (fls(batch + batch/2)-1)) - 1; + + return batch; +} + +static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch) +{ + struct per_cpu_pages *pcp; + + memset(p, 0, sizeof(*p)); + + pcp = &p->pcp; + pcp->count = 0; + pcp->high = 6 * batch; + pcp->batch = max(1UL, 1 * batch); + INIT_LIST_HEAD(&pcp->list); +} + +/* + * setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist + * to the value high for the pageset p. + */ + +static void setup_pagelist_highmark(struct per_cpu_pageset *p, + unsigned long high) +{ + struct per_cpu_pages *pcp; + + pcp = &p->pcp; + pcp->high = high; + pcp->batch = max(1UL, high/4); + if ((high/4) > (PAGE_SHIFT * 8)) + pcp->batch = PAGE_SHIFT * 8; +} + + +#ifdef CONFIG_NUMA +/* + * Boot pageset table. One per cpu which is going to be used for all + * zones and all nodes. The parameters will be set in such a way + * that an item put on a list will immediately be handed over to + * the buddy list. This is safe since pageset manipulation is done + * with interrupts disabled. + * + * Some NUMA counter updates may also be caught by the boot pagesets. + * + * The boot_pagesets must be kept even after bootup is complete for + * unused processors and/or zones. They do play a role for bootstrapping + * hotplugged processors. + * + * zoneinfo_show() and maybe other functions do + * not check if the processor is online before following the pageset pointer. + * Other parts of the kernel may not check if the zone is available. + */ +static struct per_cpu_pageset boot_pageset[NR_CPUS]; + +/* + * Dynamically allocate memory for the + * per cpu pageset array in struct zone. + */ +static int __cpuinit process_zones(int cpu) +{ + struct zone *zone, *dzone; + int node = cpu_to_node(cpu); + + node_set_state(node, N_CPU); /* this node has a cpu */ + + for_each_zone(zone) { + + if (!populated_zone(zone)) + continue; + + zone_pcp(zone, cpu) = kmalloc_node(sizeof(struct per_cpu_pageset), + GFP_KERNEL, node); + if (!zone_pcp(zone, cpu)) + goto bad; + + setup_pageset(zone_pcp(zone, cpu), zone_batchsize(zone)); + + if (percpu_pagelist_fraction) + setup_pagelist_highmark(zone_pcp(zone, cpu), + (zone->present_pages / percpu_pagelist_fraction)); + } + + return 0; +bad: + for_each_zone(dzone) { + if (!populated_zone(dzone)) + continue; + if (dzone == zone) + break; + kfree(zone_pcp(dzone, cpu)); + zone_pcp(dzone, cpu) = NULL; + } + return -ENOMEM; +} + +static inline void free_zone_pagesets(int cpu) +{ + struct zone *zone; + + for_each_zone(zone) { + struct per_cpu_pageset *pset = zone_pcp(zone, cpu); + + /* Free per_cpu_pageset if it is slab allocated */ + if (pset != &boot_pageset[cpu]) + kfree(pset); + zone_pcp(zone, cpu) = NULL; + } +} + +static int __cpuinit pageset_cpuup_callback(struct notifier_block *nfb, + unsigned long action, + void *hcpu) +{ + int cpu = (long)hcpu; + int ret = NOTIFY_OK; + + switch (action) { + case CPU_UP_PREPARE: + case CPU_UP_PREPARE_FROZEN: + if (process_zones(cpu)) + ret = NOTIFY_BAD; + break; + case CPU_UP_CANCELED: + case CPU_UP_CANCELED_FROZEN: + case CPU_DEAD: + case CPU_DEAD_FROZEN: + free_zone_pagesets(cpu); + break; + default: + break; + } + return ret; +} + +static struct notifier_block __cpuinitdata pageset_notifier = + { &pageset_cpuup_callback, NULL, 0 }; + +void __init setup_per_cpu_pageset(void) +{ + int err; + + /* Initialize per_cpu_pageset for cpu 0. + * A cpuup callback will do this for every cpu + * as it comes online + */ + err = process_zones(smp_processor_id()); + BUG_ON(err); + register_cpu_notifier(&pageset_notifier); +} + +#endif + +static noinline __init_refok +int zone_wait_table_init(struct zone *zone, unsigned long zone_size_pages) +{ + int i; + struct pglist_data *pgdat = zone->zone_pgdat; + size_t alloc_size; + + /* + * The per-page waitqueue mechanism uses hashed waitqueues + * per zone. + */ + zone->wait_table_hash_nr_entries = + wait_table_hash_nr_entries(zone_size_pages); + zone->wait_table_bits = + wait_table_bits(zone->wait_table_hash_nr_entries); + alloc_size = zone->wait_table_hash_nr_entries + * sizeof(wait_queue_head_t); + + if (!slab_is_available()) { + zone->wait_table = (wait_queue_head_t *) + alloc_bootmem_node(pgdat, alloc_size); + } else { + /* + * This case means that a zone whose size was 0 gets new memory + * via memory hot-add. + * But it may be the case that a new node was hot-added. In + * this case vmalloc() will not be able to use this new node's + * memory - this wait_table must be initialized to use this new + * node itself as well. + * To use this new node's memory, further consideration will be + * necessary. + */ + zone->wait_table = vmalloc(alloc_size); + } + if (!zone->wait_table) + return -ENOMEM; + + for(i = 0; i < zone->wait_table_hash_nr_entries; ++i) + init_waitqueue_head(zone->wait_table + i); + + return 0; +} + +static __meminit void zone_pcp_init(struct zone *zone) +{ + int cpu; + unsigned long batch = zone_batchsize(zone); + + for (cpu = 0; cpu < NR_CPUS; cpu++) { +#ifdef CONFIG_NUMA + /* Early boot. Slab allocator not functional yet */ + zone_pcp(zone, cpu) = &boot_pageset[cpu]; + setup_pageset(&boot_pageset[cpu],0); +#else + setup_pageset(zone_pcp(zone,cpu), batch); +#endif + } + if (zone->present_pages) + printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%lu\n", + zone->name, zone->present_pages, batch); +} + +__meminit int init_currently_empty_zone(struct zone *zone, + unsigned long zone_start_pfn, + unsigned long size, + enum memmap_context context) +{ + struct pglist_data *pgdat = zone->zone_pgdat; + int ret; + ret = zone_wait_table_init(zone, size); + if (ret) + return ret; + pgdat->nr_zones = zone_idx(zone) + 1; + + zone->zone_start_pfn = zone_start_pfn; + + mminit_dprintk(MMINIT_TRACE, "memmap_init", + "Initialising map node %d zone %lu pfns %lu -> %lu\n", + pgdat->node_id, + (unsigned long)zone_idx(zone), + zone_start_pfn, (zone_start_pfn + size)); + + zone_init_free_lists(zone); + + return 0; +} + +#ifdef CONFIG_ARCH_POPULATES_NODE_MAP +/* + * Basic iterator support. Return the first range of PFNs for a node + * Note: nid == MAX_NUMNODES returns first region regardless of node + */ +static int __meminit first_active_region_index_in_nid(int nid) +{ + int i; + + for (i = 0; i < nr_nodemap_entries; i++) + if (nid == MAX_NUMNODES || early_node_map[i].nid == nid) + return i; + + return -1; +} + +/* + * Basic iterator support. Return the next active range of PFNs for a node + * Note: nid == MAX_NUMNODES returns next region regardless of node + */ +static int __meminit next_active_region_index_in_nid(int index, int nid) +{ + for (index = index + 1; index < nr_nodemap_entries; index++) + if (nid == MAX_NUMNODES || early_node_map[index].nid == nid) + return index; + + return -1; +} + +#ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID +/* + * Required by SPARSEMEM. Given a PFN, return what node the PFN is on. + * Architectures may implement their own version but if add_active_range() + * was used and there are no special requirements, this is a convenient + * alternative + */ +int __meminit __early_pfn_to_nid(unsigned long pfn) +{ + int i; + + for (i = 0; i < nr_nodemap_entries; i++) { + unsigned long start_pfn = early_node_map[i].start_pfn; + unsigned long end_pfn = early_node_map[i].end_pfn; + + if (start_pfn <= pfn && pfn < end_pfn) + return early_node_map[i].nid; + } + /* This is a memory hole */ + return -1; +} +#endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */ + +int __meminit early_pfn_to_nid(unsigned long pfn) +{ + int nid; + + nid = __early_pfn_to_nid(pfn); + if (nid >= 0) + return nid; + /* just returns 0 */ + return 0; +} + +#ifdef CONFIG_NODES_SPAN_OTHER_NODES +bool __meminit early_pfn_in_nid(unsigned long pfn, int node) +{ + int nid; + + nid = __early_pfn_to_nid(pfn); + if (nid >= 0 && nid != node) + return false; + return true; +} +#endif + +/* Basic iterator support to walk early_node_map[] */ +#define for_each_active_range_index_in_nid(i, nid) \ + for (i = first_active_region_index_in_nid(nid); i != -1; \ + i = next_active_region_index_in_nid(i, nid)) + +/** + * free_bootmem_with_active_regions - Call free_bootmem_node for each active range + * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed. + * @max_low_pfn: The highest PFN that will be passed to free_bootmem_node + * + * If an architecture guarantees that all ranges registered with + * add_active_ranges() contain no holes and may be freed, this + * this function may be used instead of calling free_bootmem() manually. + */ +void __init free_bootmem_with_active_regions(int nid, + unsigned long max_low_pfn) +{ + int i; + + for_each_active_range_index_in_nid(i, nid) { + unsigned long size_pages = 0; + unsigned long end_pfn = early_node_map[i].end_pfn; + + if (early_node_map[i].start_pfn >= max_low_pfn) + continue; + + if (end_pfn > max_low_pfn) + end_pfn = max_low_pfn; + + size_pages = end_pfn - early_node_map[i].start_pfn; + free_bootmem_node(NODE_DATA(early_node_map[i].nid), + PFN_PHYS(early_node_map[i].start_pfn), + size_pages << PAGE_SHIFT); + } +} + +void __init work_with_active_regions(int nid, work_fn_t work_fn, void *data) +{ + int i; + int ret; + + for_each_active_range_index_in_nid(i, nid) { + ret = work_fn(early_node_map[i].start_pfn, + early_node_map[i].end_pfn, data); + if (ret) + break; + } +} +/** + * sparse_memory_present_with_active_regions - Call memory_present for each active range + * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used. + * + * If an architecture guarantees that all ranges registered with + * add_active_ranges() contain no holes and may be freed, this + * function may be used instead of calling memory_present() manually. + */ +void __init sparse_memory_present_with_active_regions(int nid) +{ + int i; + + for_each_active_range_index_in_nid(i, nid) + memory_present(early_node_map[i].nid, + early_node_map[i].start_pfn, + early_node_map[i].end_pfn); +} + +/** + * push_node_boundaries - Push node boundaries to at least the requested boundary + * @nid: The nid of the node to push the boundary for + * @start_pfn: The start pfn of the node + * @end_pfn: The end pfn of the node + * + * In reserve-based hot-add, mem_map is allocated that is unused until hotadd + * time. Specifically, on x86_64, SRAT will report ranges that can potentially + * be hotplugged even though no physical memory exists. This function allows + * an arch to push out the node boundaries so mem_map is allocated that can + * be used later. + */ +#ifdef CONFIG_MEMORY_HOTPLUG_RESERVE +void __init push_node_boundaries(unsigned int nid, + unsigned long start_pfn, unsigned long end_pfn) +{ + mminit_dprintk(MMINIT_TRACE, "zoneboundary", + "Entering push_node_boundaries(%u, %lu, %lu)\n", + nid, start_pfn, end_pfn); + + /* Initialise the boundary for this node if necessary */ + if (node_boundary_end_pfn[nid] == 0) + node_boundary_start_pfn[nid] = -1UL; + + /* Update the boundaries */ + if (node_boundary_start_pfn[nid] > start_pfn) + node_boundary_start_pfn[nid] = start_pfn; + if (node_boundary_end_pfn[nid] < end_pfn) + node_boundary_end_pfn[nid] = end_pfn; +} + +/* If necessary, push the node boundary out for reserve hotadd */ +static void __meminit account_node_boundary(unsigned int nid, + unsigned long *start_pfn, unsigned long *end_pfn) +{ + mminit_dprintk(MMINIT_TRACE, "zoneboundary", + "Entering account_node_boundary(%u, %lu, %lu)\n", + nid, *start_pfn, *end_pfn); + + /* Return if boundary information has not been provided */ + if (node_boundary_end_pfn[nid] == 0) + return; + + /* Check the boundaries and update if necessary */ + if (node_boundary_start_pfn[nid] < *start_pfn) + *start_pfn = node_boundary_start_pfn[nid]; + if (node_boundary_end_pfn[nid] > *end_pfn) + *end_pfn = node_boundary_end_pfn[nid]; +} +#else +void __init push_node_boundaries(unsigned int nid, + unsigned long start_pfn, unsigned long end_pfn) {} + +static void __meminit account_node_boundary(unsigned int nid, + unsigned long *start_pfn, unsigned long *end_pfn) {} +#endif + + +/** + * get_pfn_range_for_nid - Return the start and end page frames for a node + * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned. + * @start_pfn: Passed by reference. On return, it will have the node start_pfn. + * @end_pfn: Passed by reference. On return, it will have the node end_pfn. + * + * It returns the start and end page frame of a node based on information + * provided by an arch calling add_active_range(). If called for a node + * with no available memory, a warning is printed and the start and end + * PFNs will be 0. + */ +void __meminit get_pfn_range_for_nid(unsigned int nid, + unsigned long *start_pfn, unsigned long *end_pfn) +{ + int i; + *start_pfn = -1UL; + *end_pfn = 0; + + for_each_active_range_index_in_nid(i, nid) { + *start_pfn = min(*start_pfn, early_node_map[i].start_pfn); + *end_pfn = max(*end_pfn, early_node_map[i].end_pfn); + } + + if (*start_pfn == -1UL) + *start_pfn = 0; + + /* Push the node boundaries out if requested */ + account_node_boundary(nid, start_pfn, end_pfn); +} + +/* + * This finds a zone that can be used for ZONE_MOVABLE pages. The + * assumption is made that zones within a node are ordered in monotonic + * increasing memory addresses so that the "highest" populated zone is used + */ +static void __init find_usable_zone_for_movable(void) +{ + int zone_index; + for (zone_index = MAX_NR_ZONES - 1; zone_index >= 0; zone_index--) { + if (zone_index == ZONE_MOVABLE) + continue; + + if (arch_zone_highest_possible_pfn[zone_index] > + arch_zone_lowest_possible_pfn[zone_index]) + break; + } + + VM_BUG_ON(zone_index == -1); + movable_zone = zone_index; +} + +/* + * The zone ranges provided by the architecture do not include ZONE_MOVABLE + * because it is sized independant of architecture. Unlike the other zones, + * the starting point for ZONE_MOVABLE is not fixed. It may be different + * in each node depending on the size of each node and how evenly kernelcore + * is distributed. This helper function adjusts the zone ranges + * provided by the architecture for a given node by using the end of the + * highest usable zone for ZONE_MOVABLE. This preserves the assumption that + * zones within a node are in order of monotonic increases memory addresses + */ +static void __meminit adjust_zone_range_for_zone_movable(int nid, + unsigned long zone_type, + unsigned long node_start_pfn, + unsigned long node_end_pfn, + unsigned long *zone_start_pfn, + unsigned long *zone_end_pfn) +{ + /* Only adjust if ZONE_MOVABLE is on this node */ + if (zone_movable_pfn[nid]) { + /* Size ZONE_MOVABLE */ + if (zone_type == ZONE_MOVABLE) { + *zone_start_pfn = zone_movable_pfn[nid]; + *zone_end_pfn = min(node_end_pfn, + arch_zone_highest_possible_pfn[movable_zone]); + + /* Adjust for ZONE_MOVABLE starting within this range */ + } else if (*zone_start_pfn < zone_movable_pfn[nid] && + *zone_end_pfn > zone_movable_pfn[nid]) { + *zone_end_pfn = zone_movable_pfn[nid]; + + /* Check if this whole range is within ZONE_MOVABLE */ + } else if (*zone_start_pfn >= zone_movable_pfn[nid]) + *zone_start_pfn = *zone_end_pfn; + } +} + +/* + * Return the number of pages a zone spans in a node, including holes + * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node() + */ +static unsigned long __meminit zone_spanned_pages_in_node(int nid, + unsigned long zone_type, + unsigned long *ignored) +{ + unsigned long node_start_pfn, node_end_pfn; + unsigned long zone_start_pfn, zone_end_pfn; + + /* Get the start and end of the node and zone */ + get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn); + zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type]; + zone_end_pfn = arch_zone_highest_possible_pfn[zone_type]; + adjust_zone_range_for_zone_movable(nid, zone_type, + node_start_pfn, node_end_pfn, + &zone_start_pfn, &zone_end_pfn); + + /* Check that this node has pages within the zone's required range */ + if (zone_end_pfn < node_start_pfn || zone_start_pfn > node_end_pfn) + return 0; + + /* Move the zone boundaries inside the node if necessary */ + zone_end_pfn = min(zone_end_pfn, node_end_pfn); + zone_start_pfn = max(zone_start_pfn, node_start_pfn); + + /* Return the spanned pages */ + return zone_end_pfn - zone_start_pfn; +} + +/* + * Return the number of holes in a range on a node. If nid is MAX_NUMNODES, + * then all holes in the requested range will be accounted for. + */ +static unsigned long __meminit __absent_pages_in_range(int nid, + unsigned long range_start_pfn, + unsigned long range_end_pfn) +{ + int i = 0; + unsigned long prev_end_pfn = 0, hole_pages = 0; + unsigned long start_pfn; + + /* Find the end_pfn of the first active range of pfns in the node */ + i = first_active_region_index_in_nid(nid); + if (i == -1) + return 0; + + prev_end_pfn = min(early_node_map[i].start_pfn, range_end_pfn); + + /* Account for ranges before physical memory on this node */ + if (early_node_map[i].start_pfn > range_start_pfn) + hole_pages = prev_end_pfn - range_start_pfn; + + /* Find all holes for the zone within the node */ + for (; i != -1; i = next_active_region_index_in_nid(i, nid)) { + + /* No need to continue if prev_end_pfn is outside the zone */ + if (prev_end_pfn >= range_end_pfn) + break; + + /* Make sure the end of the zone is not within the hole */ + start_pfn = min(early_node_map[i].start_pfn, range_end_pfn); + prev_end_pfn = max(prev_end_pfn, range_start_pfn); + + /* Update the hole size cound and move on */ + if (start_pfn > range_start_pfn) { + BUG_ON(prev_end_pfn > start_pfn); + hole_pages += start_pfn - prev_end_pfn; + } + prev_end_pfn = early_node_map[i].end_pfn; + } + + /* Account for ranges past physical memory on this node */ + if (range_end_pfn > prev_end_pfn) + hole_pages += range_end_pfn - + max(range_start_pfn, prev_end_pfn); + + return hole_pages; +} + +/** + * absent_pages_in_range - Return number of page frames in holes within a range + * @start_pfn: The start PFN to start searching for holes + * @end_pfn: The end PFN to stop searching for holes + * + * It returns the number of pages frames in memory holes within a range. + */ +unsigned long __init absent_pages_in_range(unsigned long start_pfn, + unsigned long end_pfn) +{ + return __absent_pages_in_range(MAX_NUMNODES, start_pfn, end_pfn); +} + +/* Return the number of page frames in holes in a zone on a node */ +static unsigned long __meminit zone_absent_pages_in_node(int nid, + unsigned long zone_type, + unsigned long *ignored) +{ + unsigned long node_start_pfn, node_end_pfn; + unsigned long zone_start_pfn, zone_end_pfn; + + get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn); + zone_start_pfn = max(arch_zone_lowest_possible_pfn[zone_type], + node_start_pfn); + zone_end_pfn = min(arch_zone_highest_possible_pfn[zone_type], + node_end_pfn); + + adjust_zone_range_for_zone_movable(nid, zone_type, + node_start_pfn, node_end_pfn, + &zone_start_pfn, &zone_end_pfn); + return __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn); +} + +#else +static inline unsigned long __meminit zone_spanned_pages_in_node(int nid, + unsigned long zone_type, + unsigned long *zones_size) +{ + return zones_size[zone_type]; +} + +static inline unsigned long __meminit zone_absent_pages_in_node(int nid, + unsigned long zone_type, + unsigned long *zholes_size) +{ + if (!zholes_size) + return 0; + + return zholes_size[zone_type]; +} + +#endif + +static void __meminit calculate_node_totalpages(struct pglist_data *pgdat, + unsigned long *zones_size, unsigned long *zholes_size) +{ + unsigned long realtotalpages, totalpages = 0; + enum zone_type i; + + for (i = 0; i < MAX_NR_ZONES; i++) + totalpages += zone_spanned_pages_in_node(pgdat->node_id, i, + zones_size); + pgdat->node_spanned_pages = totalpages; + + realtotalpages = totalpages; + for (i = 0; i < MAX_NR_ZONES; i++) + realtotalpages -= + zone_absent_pages_in_node(pgdat->node_id, i, + zholes_size); + pgdat->node_present_pages = realtotalpages; + printk(KERN_DEBUG "On node %d totalpages: %lu\n", pgdat->node_id, + realtotalpages); +} + +#ifndef CONFIG_SPARSEMEM +/* + * Calculate the size of the zone->blockflags rounded to an unsigned long + * Start by making sure zonesize is a multiple of pageblock_order by rounding + * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally + * round what is now in bits to nearest long in bits, then return it in + * bytes. + */ +static unsigned long __init usemap_size(unsigned long zonesize) +{ + unsigned long usemapsize; + + usemapsize = roundup(zonesize, pageblock_nr_pages); + usemapsize = usemapsize >> pageblock_order; + usemapsize *= NR_PAGEBLOCK_BITS; + usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long)); + + return usemapsize / 8; +} + +static void __init setup_usemap(struct pglist_data *pgdat, + struct zone *zone, unsigned long zonesize) +{ + unsigned long usemapsize = usemap_size(zonesize); + zone->pageblock_flags = NULL; + if (usemapsize) { + zone->pageblock_flags = alloc_bootmem_node(pgdat, usemapsize); + memset(zone->pageblock_flags, 0, usemapsize); + } +} +#else +static void inline setup_usemap(struct pglist_data *pgdat, + struct zone *zone, unsigned long zonesize) {} +#endif /* CONFIG_SPARSEMEM */ + +#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE + +/* Return a sensible default order for the pageblock size. */ +static inline int pageblock_default_order(void) +{ + if (HPAGE_SHIFT > PAGE_SHIFT) + return HUGETLB_PAGE_ORDER; + + return MAX_ORDER-1; +} + +/* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */ +static inline void __init set_pageblock_order(unsigned int order) +{ + /* Check that pageblock_nr_pages has not already been setup */ + if (pageblock_order) + return; + + /* + * Assume the largest contiguous order of interest is a huge page. + * This value may be variable depending on boot parameters on IA64 + */ + pageblock_order = order; +} +#else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ + +/* + * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order() + * and pageblock_default_order() are unused as pageblock_order is set + * at compile-time. See include/linux/pageblock-flags.h for the values of + * pageblock_order based on the kernel config + */ +static inline int pageblock_default_order(unsigned int order) +{ + return MAX_ORDER-1; +} +#define set_pageblock_order(x) do {} while (0) + +#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ + +/* + * Set up the zone data structures: + * - mark all pages reserved + * - mark all memory queues empty + * - clear the memory bitmaps + */ +static void __paginginit free_area_init_core(struct pglist_data *pgdat, + unsigned long *zones_size, unsigned long *zholes_size) +{ + enum zone_type j; + int nid = pgdat->node_id; + unsigned long zone_start_pfn = pgdat->node_start_pfn; + int ret; + + pgdat_resize_init(pgdat); + pgdat->nr_zones = 0; + init_waitqueue_head(&pgdat->kswapd_wait); + pgdat->kswapd_max_order = 0; + pgdat_page_cgroup_init(pgdat); + + for (j = 0; j < MAX_NR_ZONES; j++) { + struct zone *zone = pgdat->node_zones + j; + unsigned long size, realsize, memmap_pages; + enum lru_list l; + + size = zone_spanned_pages_in_node(nid, j, zones_size); + realsize = size - zone_absent_pages_in_node(nid, j, + zholes_size); + + /* + * Adjust realsize so that it accounts for how much memory + * is used by this zone for memmap. This affects the watermark + * and per-cpu initialisations + */ + memmap_pages = + PAGE_ALIGN(size * sizeof(struct page)) >> PAGE_SHIFT; + if (realsize >= memmap_pages) { + realsize -= memmap_pages; + printk(KERN_DEBUG + " %s zone: %lu pages used for memmap\n", + zone_names[j], memmap_pages); + } else + printk(KERN_WARNING + " %s zone: %lu pages exceeds realsize %lu\n", + zone_names[j], memmap_pages, realsize); + + /* Account for reserved pages */ + if (j == 0 && realsize > dma_reserve) { + realsize -= dma_reserve; + printk(KERN_DEBUG " %s zone: %lu pages reserved\n", + zone_names[0], dma_reserve); + } + + if (!is_highmem_idx(j)) + nr_kernel_pages += realsize; + nr_all_pages += realsize; + + zone->spanned_pages = size; + zone->present_pages = realsize; +#ifdef CONFIG_NUMA + zone->node = nid; + zone->min_unmapped_pages = (realsize*sysctl_min_unmapped_ratio) + / 100; + zone->min_slab_pages = (realsize * sysctl_min_slab_ratio) / 100; +#endif + zone->name = zone_names[j]; + spin_lock_init(&zone->lock); + spin_lock_init(&zone->lru_lock); + zone_seqlock_init(zone); + zone->zone_pgdat = pgdat; + + zone->prev_priority = DEF_PRIORITY; + + zone_pcp_init(zone); + for_each_lru(l) { + INIT_LIST_HEAD(&zone->lru[l].list); + zone->lru[l].nr_scan = 0; + } + zone->recent_rotated[0] = 0; + zone->recent_rotated[1] = 0; + zone->recent_scanned[0] = 0; + zone->recent_scanned[1] = 0; + zap_zone_vm_stats(zone); + zone->flags = 0; + if (!size) + continue; + + set_pageblock_order(pageblock_default_order()); + setup_usemap(pgdat, zone, size); + ret = init_currently_empty_zone(zone, zone_start_pfn, + size, MEMMAP_EARLY); + BUG_ON(ret); + memmap_init(size, nid, j, zone_start_pfn); + zone_start_pfn += size; + } +} + +static void __init_refok alloc_node_mem_map(struct pglist_data *pgdat) +{ + /* Skip empty nodes */ + if (!pgdat->node_spanned_pages) + return; + +#ifdef CONFIG_FLAT_NODE_MEM_MAP + /* ia64 gets its own node_mem_map, before this, without bootmem */ + if (!pgdat->node_mem_map) { + unsigned long size, start, end; + struct page *map; + + /* + * The zone's endpoints aren't required to be MAX_ORDER + * aligned but the node_mem_map endpoints must be in order + * for the buddy allocator to function correctly. + */ + start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1); + end = pgdat->node_start_pfn + pgdat->node_spanned_pages; + end = ALIGN(end, MAX_ORDER_NR_PAGES); + size = (end - start) * sizeof(struct page); + map = alloc_remap(pgdat->node_id, size); + if (!map) + map = alloc_bootmem_node(pgdat, size); + pgdat->node_mem_map = map + (pgdat->node_start_pfn - start); + } +#ifndef CONFIG_NEED_MULTIPLE_NODES + /* + * With no DISCONTIG, the global mem_map is just set as node 0's + */ + if (pgdat == NODE_DATA(0)) { + mem_map = NODE_DATA(0)->node_mem_map; +#ifdef CONFIG_ARCH_POPULATES_NODE_MAP + if (page_to_pfn(mem_map) != pgdat->node_start_pfn) + mem_map -= (pgdat->node_start_pfn - ARCH_PFN_OFFSET); +#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */ + } +#endif +#endif /* CONFIG_FLAT_NODE_MEM_MAP */ +} + +void __paginginit free_area_init_node(int nid, unsigned long *zones_size, + unsigned long node_start_pfn, unsigned long *zholes_size) +{ + pg_data_t *pgdat = NODE_DATA(nid); + + pgdat->node_id = nid; + pgdat->node_start_pfn = node_start_pfn; + calculate_node_totalpages(pgdat, zones_size, zholes_size); + + alloc_node_mem_map(pgdat); +#ifdef CONFIG_FLAT_NODE_MEM_MAP + printk(KERN_DEBUG "free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n", + nid, (unsigned long)pgdat, + (unsigned long)pgdat->node_mem_map); +#endif + + free_area_init_core(pgdat, zones_size, zholes_size); +} + +#ifdef CONFIG_ARCH_POPULATES_NODE_MAP + +#if MAX_NUMNODES > 1 +/* + * Figure out the number of possible node ids. + */ +static void __init setup_nr_node_ids(void) +{ + unsigned int node; + unsigned int highest = 0; + + for_each_node_mask(node, node_possible_map) + highest = node; + nr_node_ids = highest + 1; +} +#else +static inline void setup_nr_node_ids(void) +{ +} +#endif + +/** + * add_active_range - Register a range of PFNs backed by physical memory + * @nid: The node ID the range resides on + * @start_pfn: The start PFN of the available physical memory + * @end_pfn: The end PFN of the available physical memory + * + * These ranges are stored in an early_node_map[] and later used by + * free_area_init_nodes() to calculate zone sizes and holes. If the + * range spans a memory hole, it is up to the architecture to ensure + * the memory is not freed by the bootmem allocator. If possible + * the range being registered will be merged with existing ranges. + */ +void __init add_active_range(unsigned int nid, unsigned long start_pfn, + unsigned long end_pfn) +{ + int i; + + mminit_dprintk(MMINIT_TRACE, "memory_register", + "Entering add_active_range(%d, %#lx, %#lx) " + "%d entries of %d used\n", + nid, start_pfn, end_pfn, + nr_nodemap_entries, MAX_ACTIVE_REGIONS); + + mminit_validate_memmodel_limits(&start_pfn, &end_pfn); + + /* Merge with existing active regions if possible */ + for (i = 0; i < nr_nodemap_entries; i++) { + if (early_node_map[i].nid != nid) + continue; + + /* Skip if an existing region covers this new one */ + if (start_pfn >= early_node_map[i].start_pfn && + end_pfn <= early_node_map[i].end_pfn) + return; + + /* Merge forward if suitable */ + if (start_pfn <= early_node_map[i].end_pfn && + end_pfn > early_node_map[i].end_pfn) { + early_node_map[i].end_pfn = end_pfn; + return; + } + + /* Merge backward if suitable */ + if (start_pfn < early_node_map[i].end_pfn && + end_pfn >= early_node_map[i].start_pfn) { + early_node_map[i].start_pfn = start_pfn; + return; + } + } + + /* Check that early_node_map is large enough */ + if (i >= MAX_ACTIVE_REGIONS) { + printk(KERN_CRIT "More than %d memory regions, truncating\n", + MAX_ACTIVE_REGIONS); + return; + } + + early_node_map[i].nid = nid; + early_node_map[i].start_pfn = start_pfn; + early_node_map[i].end_pfn = end_pfn; + nr_nodemap_entries = i + 1; +} + +/** + * remove_active_range - Shrink an existing registered range of PFNs + * @nid: The node id the range is on that should be shrunk + * @start_pfn: The new PFN of the range + * @end_pfn: The new PFN of the range + * + * i386 with NUMA use alloc_remap() to store a node_mem_map on a local node. + * The map is kept near the end physical page range that has already been + * registered. This function allows an arch to shrink an existing registered + * range. + */ +void __init remove_active_range(unsigned int nid, unsigned long start_pfn, + unsigned long end_pfn) +{ + int i, j; + int removed = 0; + + printk(KERN_DEBUG "remove_active_range (%d, %lu, %lu)\n", + nid, start_pfn, end_pfn); + + /* Find the old active region end and shrink */ + for_each_active_range_index_in_nid(i, nid) { + if (early_node_map[i].start_pfn >= start_pfn && + early_node_map[i].end_pfn <= end_pfn) { + /* clear it */ + early_node_map[i].start_pfn = 0; + early_node_map[i].end_pfn = 0; + removed = 1; + continue; + } + if (early_node_map[i].start_pfn < start_pfn && + early_node_map[i].end_pfn > start_pfn) { + unsigned long temp_end_pfn = early_node_map[i].end_pfn; + early_node_map[i].end_pfn = start_pfn; + if (temp_end_pfn > end_pfn) + add_active_range(nid, end_pfn, temp_end_pfn); + continue; + } + if (early_node_map[i].start_pfn >= start_pfn && + early_node_map[i].end_pfn > end_pfn && + early_node_map[i].start_pfn < end_pfn) { + early_node_map[i].start_pfn = end_pfn; + continue; + } + } + + if (!removed) + return; + + /* remove the blank ones */ + for (i = nr_nodemap_entries - 1; i > 0; i--) { + if (early_node_map[i].nid != nid) + continue; + if (early_node_map[i].end_pfn) + continue; + /* we found it, get rid of it */ + for (j = i; j < nr_nodemap_entries - 1; j++) + memcpy(&early_node_map[j], &early_node_map[j+1], + sizeof(early_node_map[j])); + j = nr_nodemap_entries - 1; + memset(&early_node_map[j], 0, sizeof(early_node_map[j])); + nr_nodemap_entries--; + } +} + +/** + * remove_all_active_ranges - Remove all currently registered regions + * + * During discovery, it may be found that a table like SRAT is invalid + * and an alternative discovery method must be used. This function removes + * all currently registered regions. + */ +void __init remove_all_active_ranges(void) +{ + memset(early_node_map, 0, sizeof(early_node_map)); + nr_nodemap_entries = 0; +#ifdef CONFIG_MEMORY_HOTPLUG_RESERVE + memset(node_boundary_start_pfn, 0, sizeof(node_boundary_start_pfn)); + memset(node_boundary_end_pfn, 0, sizeof(node_boundary_end_pfn)); +#endif /* CONFIG_MEMORY_HOTPLUG_RESERVE */ +} + +/* Compare two active node_active_regions */ +static int __init cmp_node_active_region(const void *a, const void *b) +{ + struct node_active_region *arange = (struct node_active_region *)a; + struct node_active_region *brange = (struct node_active_region *)b; + + /* Done this way to avoid overflows */ + if (arange->start_pfn > brange->start_pfn) + return 1; + if (arange->start_pfn < brange->start_pfn) + return -1; + + return 0; +} + +/* sort the node_map by start_pfn */ +static void __init sort_node_map(void) +{ + sort(early_node_map, (size_t)nr_nodemap_entries, + sizeof(struct node_active_region), + cmp_node_active_region, NULL); +} + +/* Find the lowest pfn for a node */ +static unsigned long __init find_min_pfn_for_node(int nid) +{ + int i; + unsigned long min_pfn = ULONG_MAX; + + /* Assuming a sorted map, the first range found has the starting pfn */ + for_each_active_range_index_in_nid(i, nid) + min_pfn = min(min_pfn, early_node_map[i].start_pfn); + + if (min_pfn == ULONG_MAX) { + printk(KERN_WARNING + "Could not find start_pfn for node %d\n", nid); + return 0; + } + + return min_pfn; +} + +/** + * find_min_pfn_with_active_regions - Find the minimum PFN registered + * + * It returns the minimum PFN based on information provided via + * add_active_range(). + */ +unsigned long __init find_min_pfn_with_active_regions(void) +{ + return find_min_pfn_for_node(MAX_NUMNODES); +} + +/* + * early_calculate_totalpages() + * Sum pages in active regions for movable zone. + * Populate N_HIGH_MEMORY for calculating usable_nodes. + */ +static unsigned long __init early_calculate_totalpages(void) +{ + int i; + unsigned long totalpages = 0; + + for (i = 0; i < nr_nodemap_entries; i++) { + unsigned long pages = early_node_map[i].end_pfn - + early_node_map[i].start_pfn; + totalpages += pages; + if (pages) + node_set_state(early_node_map[i].nid, N_HIGH_MEMORY); + } + return totalpages; +} + +/* + * Find the PFN the Movable zone begins in each node. Kernel memory + * is spread evenly between nodes as long as the nodes have enough + * memory. When they don't, some nodes will have more kernelcore than + * others + */ +static void __init find_zone_movable_pfns_for_nodes(unsigned long *movable_pfn) +{ + int i, nid; + unsigned long usable_startpfn; + unsigned long kernelcore_node, kernelcore_remaining; + unsigned long totalpages = early_calculate_totalpages(); + int usable_nodes = nodes_weight(node_states[N_HIGH_MEMORY]); + + /* + * If movablecore was specified, calculate what size of + * kernelcore that corresponds so that memory usable for + * any allocation type is evenly spread. If both kernelcore + * and movablecore are specified, then the value of kernelcore + * will be used for required_kernelcore if it's greater than + * what movablecore would have allowed. + */ + if (required_movablecore) { + unsigned long corepages; + + /* + * Round-up so that ZONE_MOVABLE is at least as large as what + * was requested by the user + */ + required_movablecore = + roundup(required_movablecore, MAX_ORDER_NR_PAGES); + corepages = totalpages - required_movablecore; + + required_kernelcore = max(required_kernelcore, corepages); + } + + /* If kernelcore was not specified, there is no ZONE_MOVABLE */ + if (!required_kernelcore) + return; + + /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */ + find_usable_zone_for_movable(); + usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone]; + +restart: + /* Spread kernelcore memory as evenly as possible throughout nodes */ + kernelcore_node = required_kernelcore / usable_nodes; + for_each_node_state(nid, N_HIGH_MEMORY) { + /* + * Recalculate kernelcore_node if the division per node + * now exceeds what is necessary to satisfy the requested + * amount of memory for the kernel + */ + if (required_kernelcore < kernelcore_node) + kernelcore_node = required_kernelcore / usable_nodes; + + /* + * As the map is walked, we track how much memory is usable + * by the kernel using kernelcore_remaining. When it is + * 0, the rest of the node is usable by ZONE_MOVABLE + */ + kernelcore_remaining = kernelcore_node; + + /* Go through each range of PFNs within this node */ + for_each_active_range_index_in_nid(i, nid) { + unsigned long start_pfn, end_pfn; + unsigned long size_pages; + + start_pfn = max(early_node_map[i].start_pfn, + zone_movable_pfn[nid]); + end_pfn = early_node_map[i].end_pfn; + if (start_pfn >= end_pfn) + continue; + + /* Account for what is only usable for kernelcore */ + if (start_pfn < usable_startpfn) { + unsigned long kernel_pages; + kernel_pages = min(end_pfn, usable_startpfn) + - start_pfn; + + kernelcore_remaining -= min(kernel_pages, + kernelcore_remaining); + required_kernelcore -= min(kernel_pages, + required_kernelcore); + + /* Continue if range is now fully accounted */ + if (end_pfn <= usable_startpfn) { + + /* + * Push zone_movable_pfn to the end so + * that if we have to rebalance + * kernelcore across nodes, we will + * not double account here + */ + zone_movable_pfn[nid] = end_pfn; + continue; + } + start_pfn = usable_startpfn; + } + + /* + * The usable PFN range for ZONE_MOVABLE is from + * start_pfn->end_pfn. Calculate size_pages as the + * number of pages used as kernelcore + */ + size_pages = end_pfn - start_pfn; + if (size_pages > kernelcore_remaining) + size_pages = kernelcore_remaining; + zone_movable_pfn[nid] = start_pfn + size_pages; + + /* + * Some kernelcore has been met, update counts and + * break if the kernelcore for this node has been + * satisified + */ + required_kernelcore -= min(required_kernelcore, + size_pages); + kernelcore_remaining -= size_pages; + if (!kernelcore_remaining) + break; + } + } + + /* + * If there is still required_kernelcore, we do another pass with one + * less node in the count. This will push zone_movable_pfn[nid] further + * along on the nodes that still have memory until kernelcore is + * satisified + */ + usable_nodes--; + if (usable_nodes && required_kernelcore > usable_nodes) + goto restart; + + /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */ + for (nid = 0; nid < MAX_NUMNODES; nid++) + zone_movable_pfn[nid] = + roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES); +} + +/* Any regular memory on that node ? */ +static void check_for_regular_memory(pg_data_t *pgdat) +{ +#ifdef CONFIG_HIGHMEM + enum zone_type zone_type; + + for (zone_type = 0; zone_type <= ZONE_NORMAL; zone_type++) { + struct zone *zone = &pgdat->node_zones[zone_type]; + if (zone->present_pages) + node_set_state(zone_to_nid(zone), N_NORMAL_MEMORY); + } +#endif +} + +/** + * free_area_init_nodes - Initialise all pg_data_t and zone data + * @max_zone_pfn: an array of max PFNs for each zone + * + * This will call free_area_init_node() for each active node in the system. + * Using the page ranges provided by add_active_range(), the size of each + * zone in each node and their holes is calculated. If the maximum PFN + * between two adjacent zones match, it is assumed that the zone is empty. + * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed + * that arch_max_dma32_pfn has no pages. It is also assumed that a zone + * starts where the previous one ended. For example, ZONE_DMA32 starts + * at arch_max_dma_pfn. + */ +void __init free_area_init_nodes(unsigned long *max_zone_pfn) +{ + unsigned long nid; + int i; + + /* Sort early_node_map as initialisation assumes it is sorted */ + sort_node_map(); + + /* Record where the zone boundaries are */ + memset(arch_zone_lowest_possible_pfn, 0, + sizeof(arch_zone_lowest_possible_pfn)); + memset(arch_zone_highest_possible_pfn, 0, + sizeof(arch_zone_highest_possible_pfn)); + arch_zone_lowest_possible_pfn[0] = find_min_pfn_with_active_regions(); + arch_zone_highest_possible_pfn[0] = max_zone_pfn[0]; + for (i = 1; i < MAX_NR_ZONES; i++) { + if (i == ZONE_MOVABLE) + continue; + arch_zone_lowest_possible_pfn[i] = + arch_zone_highest_possible_pfn[i-1]; + arch_zone_highest_possible_pfn[i] = + max(max_zone_pfn[i], arch_zone_lowest_possible_pfn[i]); + } + arch_zone_lowest_possible_pfn[ZONE_MOVABLE] = 0; + arch_zone_highest_possible_pfn[ZONE_MOVABLE] = 0; + + /* Find the PFNs that ZONE_MOVABLE begins at in each node */ + memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn)); + find_zone_movable_pfns_for_nodes(zone_movable_pfn); + + /* Print out the zone ranges */ + printk("Zone PFN ranges:\n"); + for (i = 0; i < MAX_NR_ZONES; i++) { + if (i == ZONE_MOVABLE) + continue; + printk(" %-8s %0#10lx -> %0#10lx\n", + zone_names[i], + arch_zone_lowest_possible_pfn[i], + arch_zone_highest_possible_pfn[i]); + } + + /* Print out the PFNs ZONE_MOVABLE begins at in each node */ + printk("Movable zone start PFN for each node\n"); + for (i = 0; i < MAX_NUMNODES; i++) { + if (zone_movable_pfn[i]) + printk(" Node %d: %lu\n", i, zone_movable_pfn[i]); + } + + /* Print out the early_node_map[] */ + printk("early_node_map[%d] active PFN ranges\n", nr_nodemap_entries); + for (i = 0; i < nr_nodemap_entries; i++) + printk(" %3d: %0#10lx -> %0#10lx\n", early_node_map[i].nid, + early_node_map[i].start_pfn, + early_node_map[i].end_pfn); + + /* Initialise every node */ + mminit_verify_pageflags_layout(); + setup_nr_node_ids(); + for_each_online_node(nid) { + pg_data_t *pgdat = NODE_DATA(nid); + free_area_init_node(nid, NULL, + find_min_pfn_for_node(nid), NULL); + + /* Any memory on that node */ + if (pgdat->node_present_pages) + node_set_state(nid, N_HIGH_MEMORY); + check_for_regular_memory(pgdat); + } +} + +static int __init cmdline_parse_core(char *p, unsigned long *core) +{ + unsigned long long coremem; + if (!p) + return -EINVAL; + + coremem = memparse(p, &p); + *core = coremem >> PAGE_SHIFT; + + /* Paranoid check that UL is enough for the coremem value */ + WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX); + + return 0; +} + +/* + * kernelcore=size sets the amount of memory for use for allocations that + * cannot be reclaimed or migrated. + */ +static int __init cmdline_parse_kernelcore(char *p) +{ + return cmdline_parse_core(p, &required_kernelcore); +} + +/* + * movablecore=size sets the amount of memory for use for allocations that + * can be reclaimed or migrated. + */ +static int __init cmdline_parse_movablecore(char *p) +{ + return cmdline_parse_core(p, &required_movablecore); +} + +early_param("kernelcore", cmdline_parse_kernelcore); +early_param("movablecore", cmdline_parse_movablecore); + +#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */ + +/** + * set_dma_reserve - set the specified number of pages reserved in the first zone + * @new_dma_reserve: The number of pages to mark reserved + * + * The per-cpu batchsize and zone watermarks are determined by present_pages. + * In the DMA zone, a significant percentage may be consumed by kernel image + * and other unfreeable allocations which can skew the watermarks badly. This + * function may optionally be used to account for unfreeable pages in the + * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and + * smaller per-cpu batchsize. + */ +void __init set_dma_reserve(unsigned long new_dma_reserve) +{ + dma_reserve = new_dma_reserve; +} + +#ifndef CONFIG_NEED_MULTIPLE_NODES +struct pglist_data __refdata contig_page_data = { .bdata = &bootmem_node_data[0] }; +EXPORT_SYMBOL(contig_page_data); +#endif + +void __init free_area_init(unsigned long *zones_size) +{ + free_area_init_node(0, zones_size, + __pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL); +} + +static int page_alloc_cpu_notify(struct notifier_block *self, + unsigned long action, void *hcpu) +{ + int cpu = (unsigned long)hcpu; + + if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) { + drain_pages(cpu); + + /* + * Spill the event counters of the dead processor + * into the current processors event counters. + * This artificially elevates the count of the current + * processor. + */ + vm_events_fold_cpu(cpu); + + /* + * Zero the differential counters of the dead processor + * so that the vm statistics are consistent. + * + * This is only okay since the processor is dead and cannot + * race with what we are doing. + */ + refresh_cpu_vm_stats(cpu); + } + return NOTIFY_OK; +} + +void __init page_alloc_init(void) +{ + hotcpu_notifier(page_alloc_cpu_notify, 0); +} + +/* + * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio + * or min_free_kbytes changes. + */ +static void calculate_totalreserve_pages(void) +{ + struct pglist_data *pgdat; + unsigned long reserve_pages = 0; + enum zone_type i, j; + + for_each_online_pgdat(pgdat) { + for (i = 0; i < MAX_NR_ZONES; i++) { + struct zone *zone = pgdat->node_zones + i; + unsigned long max = 0; + + /* Find valid and maximum lowmem_reserve in the zone */ + for (j = i; j < MAX_NR_ZONES; j++) { + if (zone->lowmem_reserve[j] > max) + max = zone->lowmem_reserve[j]; + } + + /* we treat pages_high as reserved pages. */ + max += zone->pages_high; + + if (max > zone->present_pages) + max = zone->present_pages; + reserve_pages += max; + } + } + totalreserve_pages = reserve_pages; +} + +/* + * setup_per_zone_lowmem_reserve - called whenever + * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone + * has a correct pages reserved value, so an adequate number of + * pages are left in the zone after a successful __alloc_pages(). + */ +static void setup_per_zone_lowmem_reserve(void) +{ + struct pglist_data *pgdat; + enum zone_type j, idx; + + for_each_online_pgdat(pgdat) { + for (j = 0; j < MAX_NR_ZONES; j++) { + struct zone *zone = pgdat->node_zones + j; + unsigned long present_pages = zone->present_pages; + + zone->lowmem_reserve[j] = 0; + + idx = j; + while (idx) { + struct zone *lower_zone; + + idx--; + + if (sysctl_lowmem_reserve_ratio[idx] < 1) + sysctl_lowmem_reserve_ratio[idx] = 1; + + lower_zone = pgdat->node_zones + idx; + lower_zone->lowmem_reserve[j] = present_pages / + sysctl_lowmem_reserve_ratio[idx]; + present_pages += lower_zone->present_pages; + } + } + } + + /* update totalreserve_pages */ + calculate_totalreserve_pages(); +} + +/** + * setup_per_zone_pages_min - called when min_free_kbytes changes. + * + * Ensures that the pages_{min,low,high} values for each zone are set correctly + * with respect to min_free_kbytes. + */ +void setup_per_zone_pages_min(void) +{ + unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10); + unsigned long lowmem_pages = 0; + struct zone *zone; + unsigned long flags; + + /* Calculate total number of !ZONE_HIGHMEM pages */ + for_each_zone(zone) { + if (!is_highmem(zone)) + lowmem_pages += zone->present_pages; + } + + for_each_zone(zone) { + u64 tmp; + + spin_lock_irqsave(&zone->lock, flags); + tmp = (u64)pages_min * zone->present_pages; + do_div(tmp, lowmem_pages); + if (is_highmem(zone)) { + /* + * __GFP_HIGH and PF_MEMALLOC allocations usually don't + * need highmem pages, so cap pages_min to a small + * value here. + * + * The (pages_high-pages_low) and (pages_low-pages_min) + * deltas controls asynch page reclaim, and so should + * not be capped for highmem. + */ + int min_pages; + + min_pages = zone->present_pages / 1024; + if (min_pages < SWAP_CLUSTER_MAX) + min_pages = SWAP_CLUSTER_MAX; + if (min_pages > 128) + min_pages = 128; + zone->pages_min = min_pages; + } else { + /* + * If it's a lowmem zone, reserve a number of pages + * proportionate to the zone's size. + */ + zone->pages_min = tmp; + } + + zone->pages_low = zone->pages_min + (tmp >> 2); + zone->pages_high = zone->pages_min + (tmp >> 1); + setup_zone_migrate_reserve(zone); + spin_unlock_irqrestore(&zone->lock, flags); + } + + /* update totalreserve_pages */ + calculate_totalreserve_pages(); +} + +/** + * setup_per_zone_inactive_ratio - called when min_free_kbytes changes. + * + * The inactive anon list should be small enough that the VM never has to + * do too much work, but large enough that each inactive page has a chance + * to be referenced again before it is swapped out. + * + * The inactive_anon ratio is the target ratio of ACTIVE_ANON to + * INACTIVE_ANON pages on this zone's LRU, maintained by the + * pageout code. A zone->inactive_ratio of 3 means 3:1 or 25% of + * the anonymous pages are kept on the inactive list. + * + * total target max + * memory ratio inactive anon + * ------------------------------------- + * 10MB 1 5MB + * 100MB 1 50MB + * 1GB 3 250MB + * 10GB 10 0.9GB + * 100GB 31 3GB + * 1TB 101 10GB + * 10TB 320 32GB + */ +void setup_per_zone_inactive_ratio(void) +{ + struct zone *zone; + + for_each_zone(zone) { + unsigned int gb, ratio; + + /* Zone size in gigabytes */ + gb = zone->present_pages >> (30 - PAGE_SHIFT); + ratio = int_sqrt(10 * gb); + if (!ratio) + ratio = 1; + + zone->inactive_ratio = ratio; + } +} + +/* + * Initialise min_free_kbytes. + * + * For small machines we want it small (128k min). For large machines + * we want it large (64MB max). But it is not linear, because network + * bandwidth does not increase linearly with machine size. We use + * + * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy: + * min_free_kbytes = sqrt(lowmem_kbytes * 16) + * + * which yields + * + * 16MB: 512k + * 32MB: 724k + * 64MB: 1024k + * 128MB: 1448k + * 256MB: 2048k + * 512MB: 2896k + * 1024MB: 4096k + * 2048MB: 5792k + * 4096MB: 8192k + * 8192MB: 11584k + * 16384MB: 16384k + */ +static int __init init_per_zone_pages_min(void) +{ + unsigned long lowmem_kbytes; + + lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10); + + min_free_kbytes = int_sqrt(lowmem_kbytes * 16); + if (min_free_kbytes < 128) + min_free_kbytes = 128; + if (min_free_kbytes > 65536) + min_free_kbytes = 65536; + setup_per_zone_pages_min(); + setup_per_zone_lowmem_reserve(); + setup_per_zone_inactive_ratio(); + return 0; +} +module_init(init_per_zone_pages_min) + +/* + * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so + * that we can call two helper functions whenever min_free_kbytes + * changes. + */ +int min_free_kbytes_sysctl_handler(ctl_table *table, int write, + struct file *file, void __user *buffer, size_t *length, loff_t *ppos) +{ + proc_dointvec(table, write, file, buffer, length, ppos); + if (write) + setup_per_zone_pages_min(); + return 0; +} + +#ifdef CONFIG_NUMA +int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table *table, int write, + struct file *file, void __user *buffer, size_t *length, loff_t *ppos) +{ + struct zone *zone; + int rc; + + rc = proc_dointvec_minmax(table, write, file, buffer, length, ppos); + if (rc) + return rc; + + for_each_zone(zone) + zone->min_unmapped_pages = (zone->present_pages * + sysctl_min_unmapped_ratio) / 100; + return 0; +} + +int sysctl_min_slab_ratio_sysctl_handler(ctl_table *table, int write, + struct file *file, void __user *buffer, size_t *length, loff_t *ppos) +{ + struct zone *zone; + int rc; + + rc = proc_dointvec_minmax(table, write, file, buffer, length, ppos); + if (rc) + return rc; + + for_each_zone(zone) + zone->min_slab_pages = (zone->present_pages * + sysctl_min_slab_ratio) / 100; + return 0; +} +#endif + +/* + * lowmem_reserve_ratio_sysctl_handler - just a wrapper around + * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve() + * whenever sysctl_lowmem_reserve_ratio changes. + * + * The reserve ratio obviously has absolutely no relation with the + * pages_min watermarks. The lowmem reserve ratio can only make sense + * if in function of the boot time zone sizes. + */ +int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write, + struct file *file, void __user *buffer, size_t *length, loff_t *ppos) +{ + proc_dointvec_minmax(table, write, file, buffer, length, ppos); + setup_per_zone_lowmem_reserve(); + return 0; +} + +/* + * percpu_pagelist_fraction - changes the pcp->high for each zone on each + * cpu. It is the fraction of total pages in each zone that a hot per cpu pagelist + * can have before it gets flushed back to buddy allocator. + */ + +int percpu_pagelist_fraction_sysctl_handler(ctl_table *table, int write, + struct file *file, void __user *buffer, size_t *length, loff_t *ppos) +{ + struct zone *zone; + unsigned int cpu; + int ret; + + ret = proc_dointvec_minmax(table, write, file, buffer, length, ppos); + if (!write || (ret == -EINVAL)) + return ret; + for_each_zone(zone) { + for_each_online_cpu(cpu) { + unsigned long high; + high = zone->present_pages / percpu_pagelist_fraction; + setup_pagelist_highmark(zone_pcp(zone, cpu), high); + } + } + return 0; +} + +int hashdist = HASHDIST_DEFAULT; + +#ifdef CONFIG_NUMA +static int __init set_hashdist(char *str) +{ + if (!str) + return 0; + hashdist = simple_strtoul(str, &str, 0); + return 1; +} +__setup("hashdist=", set_hashdist); +#endif + +/* + * allocate a large system hash table from bootmem + * - it is assumed that the hash table must contain an exact power-of-2 + * quantity of entries + * - limit is the number of hash buckets, not the total allocation size + */ +void *__init alloc_large_system_hash(const char *tablename, + unsigned long bucketsize, + unsigned long numentries, + int scale, + int flags, + unsigned int *_hash_shift, + unsigned int *_hash_mask, + unsigned long limit) +{ + unsigned long long max = limit; + unsigned long log2qty, size; + void *table = NULL; + + /* allow the kernel cmdline to have a say */ + if (!numentries) { + /* round applicable memory size up to nearest megabyte */ + numentries = nr_kernel_pages; + numentries += (1UL << (20 - PAGE_SHIFT)) - 1; + numentries >>= 20 - PAGE_SHIFT; + numentries <<= 20 - PAGE_SHIFT; + + /* limit to 1 bucket per 2^scale bytes of low memory */ + if (scale > PAGE_SHIFT) + numentries >>= (scale - PAGE_SHIFT); + else + numentries <<= (PAGE_SHIFT - scale); + + /* Make sure we've got at least a 0-order allocation.. */ + if (unlikely((numentries * bucketsize) < PAGE_SIZE)) + numentries = PAGE_SIZE / bucketsize; + } + numentries = roundup_pow_of_two(numentries); + + /* limit allocation size to 1/16 total memory by default */ + if (max == 0) { + max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4; + do_div(max, bucketsize); + } + + if (numentries > max) + numentries = max; + + log2qty = ilog2(numentries); + + do { + size = bucketsize << log2qty; + if (flags & HASH_EARLY) + table = alloc_bootmem_nopanic(size); + else if (hashdist) + table = __vmalloc(size, GFP_ATOMIC, PAGE_KERNEL); + else { + unsigned long order = get_order(size); + table = (void*) __get_free_pages(GFP_ATOMIC, order); + /* + * If bucketsize is not a power-of-two, we may free + * some pages at the end of hash table. + */ + if (table) { + unsigned long alloc_end = (unsigned long)table + + (PAGE_SIZE << order); + unsigned long used = (unsigned long)table + + PAGE_ALIGN(size); + split_page(virt_to_page(table), order); + while (used < alloc_end) { + free_page(used); + used += PAGE_SIZE; + } + } + } + } while (!table && size > PAGE_SIZE && --log2qty); + + if (!table) + panic("Failed to allocate %s hash table\n", tablename); + + printk(KERN_INFO "%s hash table entries: %d (order: %d, %lu bytes)\n", + tablename, + (1U << log2qty), + ilog2(size) - PAGE_SHIFT, + size); + + if (_hash_shift) + *_hash_shift = log2qty; + if (_hash_mask) + *_hash_mask = (1 << log2qty) - 1; + + return table; +} + +#ifdef CONFIG_OUT_OF_LINE_PFN_TO_PAGE +struct page *pfn_to_page(unsigned long pfn) +{ + return __pfn_to_page(pfn); +} +unsigned long page_to_pfn(struct page *page) +{ + return __page_to_pfn(page); +} +EXPORT_SYMBOL(pfn_to_page); +EXPORT_SYMBOL(page_to_pfn); +#endif /* CONFIG_OUT_OF_LINE_PFN_TO_PAGE */ + +/* Return a pointer to the bitmap storing bits affecting a block of pages */ +static inline unsigned long *get_pageblock_bitmap(struct zone *zone, + unsigned long pfn) +{ +#ifdef CONFIG_SPARSEMEM + return __pfn_to_section(pfn)->pageblock_flags; +#else + return zone->pageblock_flags; +#endif /* CONFIG_SPARSEMEM */ +} + +static inline int pfn_to_bitidx(struct zone *zone, unsigned long pfn) +{ +#ifdef CONFIG_SPARSEMEM + pfn &= (PAGES_PER_SECTION-1); + return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS; +#else + pfn = pfn - zone->zone_start_pfn; + return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS; +#endif /* CONFIG_SPARSEMEM */ +} + +/** + * get_pageblock_flags_group - Return the requested group of flags for the pageblock_nr_pages block of pages + * @page: The page within the block of interest + * @start_bitidx: The first bit of interest to retrieve + * @end_bitidx: The last bit of interest + * returns pageblock_bits flags + */ +unsigned long get_pageblock_flags_group(struct page *page, + int start_bitidx, int end_bitidx) +{ + struct zone *zone; + unsigned long *bitmap; + unsigned long pfn, bitidx; + unsigned long flags = 0; + unsigned long value = 1; + + zone = page_zone(page); + pfn = page_to_pfn(page); + bitmap = get_pageblock_bitmap(zone, pfn); + bitidx = pfn_to_bitidx(zone, pfn); + + for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1) + if (test_bit(bitidx + start_bitidx, bitmap)) + flags |= value; + + return flags; +} + +/** + * set_pageblock_flags_group - Set the requested group of flags for a pageblock_nr_pages block of pages + * @page: The page within the block of interest + * @start_bitidx: The first bit of interest + * @end_bitidx: The last bit of interest + * @flags: The flags to set + */ +void set_pageblock_flags_group(struct page *page, unsigned long flags, + int start_bitidx, int end_bitidx) +{ + struct zone *zone; + unsigned long *bitmap; + unsigned long pfn, bitidx; + unsigned long value = 1; + + zone = page_zone(page); + pfn = page_to_pfn(page); + bitmap = get_pageblock_bitmap(zone, pfn); + bitidx = pfn_to_bitidx(zone, pfn); + VM_BUG_ON(pfn < zone->zone_start_pfn); + VM_BUG_ON(pfn >= zone->zone_start_pfn + zone->spanned_pages); + + for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1) + if (flags & value) + __set_bit(bitidx + start_bitidx, bitmap); + else + __clear_bit(bitidx + start_bitidx, bitmap); +} + +/* + * This is designed as sub function...plz see page_isolation.c also. + * set/clear page block's type to be ISOLATE. + * page allocater never alloc memory from ISOLATE block. + */ + +int set_migratetype_isolate(struct page *page) +{ + struct zone *zone; + unsigned long flags; + int ret = -EBUSY; + + zone = page_zone(page); + spin_lock_irqsave(&zone->lock, flags); + /* + * In future, more migrate types will be able to be isolation target. + */ + if (get_pageblock_migratetype(page) != MIGRATE_MOVABLE) + goto out; + set_pageblock_migratetype(page, MIGRATE_ISOLATE); + move_freepages_block(zone, page, MIGRATE_ISOLATE); + ret = 0; +out: + spin_unlock_irqrestore(&zone->lock, flags); + if (!ret) + drain_all_pages(); + return ret; +} + +void unset_migratetype_isolate(struct page *page) +{ + struct zone *zone; + unsigned long flags; + zone = page_zone(page); + spin_lock_irqsave(&zone->lock, flags); + if (get_pageblock_migratetype(page) != MIGRATE_ISOLATE) + goto out; + set_pageblock_migratetype(page, MIGRATE_MOVABLE); + move_freepages_block(zone, page, MIGRATE_MOVABLE); +out: + spin_unlock_irqrestore(&zone->lock, flags); +} + +#ifdef CONFIG_MEMORY_HOTREMOVE +/* + * All pages in the range must be isolated before calling this. + */ +void +__offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) +{ + struct page *page; + struct zone *zone; + int order, i; + unsigned long pfn; + unsigned long flags; + /* find the first valid pfn */ + for (pfn = start_pfn; pfn < end_pfn; pfn++) + if (pfn_valid(pfn)) + break; + if (pfn == end_pfn) + return; + zone = page_zone(pfn_to_page(pfn)); + spin_lock_irqsave(&zone->lock, flags); + pfn = start_pfn; + while (pfn < end_pfn) { + if (!pfn_valid(pfn)) { + pfn++; + continue; + } + page = pfn_to_page(pfn); + BUG_ON(page_count(page)); + BUG_ON(!PageBuddy(page)); + order = page_order(page); +#ifdef CONFIG_DEBUG_VM + printk(KERN_INFO "remove from free list %lx %d %lx\n", + pfn, 1 << order, end_pfn); +#endif + list_del(&page->lru); + rmv_page_order(page); + zone->free_area[order].nr_free--; + __mod_zone_page_state(zone, NR_FREE_PAGES, + - (1UL << order)); + for (i = 0; i < (1 << order); i++) + SetPageReserved((page+i)); + pfn += (1 << order); + } + spin_unlock_irqrestore(&zone->lock, flags); +} +#endif |
