litmus-rt.git - The LITMUS^RT kernel.

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author	Roel Kluin <12o3l@tiscali.nl>	2008-04-28 05:15:10 -0400
committer	Linus Torvalds <torvalds@linux-foundation.org>	2008-04-28 11:58:37 -0400
commit	af2afd247f0fae25d66f210fb800fe6a2958366e (patch)
tree	0245418583bca2eba725090331f6c8fec29766e1 /drivers
parent	9e3f0ca812ab8fa3f4e65ade41bf6fb936f14e15 (diff)

drivers/video/aty/aty128fb.c: fix incorrect usage of strncat in aty128_init()

Fix incorrect length for strncat by replacing it with strlcat Signed-off-by: Roel Kluin <12o3l@tiscali.nl> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Diffstat (limited to 'drivers')

-rw-r--r--

drivers/video/aty/aty128fb.c

1 files changed, 1 insertions, 1 deletions


diff --git a/drivers/video/aty/aty128fb.c b/drivers/video/aty/aty128fb.c index cbd3308b6690..27faffdee11b 100644 --- a/drivers/video/aty/aty128fb.c +++ b/drivers/video/aty/aty128fb.c
@@ -1885,7 +1885,7 @@ static int __devinit aty128_init(struct pci_dev *pdev, const struct pci_device_i
1885		1885
1886	/* range check to make sure */	1886	/* range check to make sure */
1887	if (ent->driver_data < ARRAY_SIZE(r128_family))	1887	if (ent->driver_data < ARRAY_SIZE(r128_family))
1888	strncat(video_card, r128_family[ent->driver_data], sizeof(video_card));	1888	strlcat(video_card, r128_family[ent->driver_data], sizeof(video_card));
1889		1889
1890	printk(KERN_INFO "aty128fb: %s [chip rev 0x%x] ", video_card, chip_rev);	1890	printk(KERN_INFO "aty128fb: %s [chip rev 0x%x] ", video_card, chip_rev);
1891		1891

/* * 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/memblock.h> #include <linux/compiler.h> #include <linux/kernel.h> #include <linux/kmemcheck.h> #include <linux/module.h> #include <linux/suspend.h> #include <linux/pagevec.h> #include <linux/blkdev.h> #include <linux/slab.h> #include <linux/ratelimit.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/vmstat.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 <linux/kmemleak.h> #include <linux/compaction.h> #include <trace/events/kmem.h> #include <linux/ftrace_event.h> #include <linux/memcontrol.h> #include <linux/prefetch.h> #include <linux/mm_inline.h> #include <linux/migrate.h> #include <linux/page-debug-flags.h> #include <linux/hugetlb.h> #include <linux/sched/rt.h> #include <asm/sections.h> #include <asm/tlbflush.h> #include <asm/div64.h> #include "internal.h" /* prevent >1 _updater_ of zone percpu pageset ->high and ->batch fields */ static DEFINE_MUTEX(pcp_batch_high_lock); #ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID DEFINE_PER_CPU(int, numa_node); EXPORT_PER_CPU_SYMBOL(numa_node); #endif #ifdef CONFIG_HAVE_MEMORYLESS_NODES /* * N.B., Do NOT reference the '_numa_mem_' per cpu variable directly. * It will not be defined when CONFIG_HAVE_MEMORYLESS_NODES is not defined. * Use the accessor functions set_numa_mem(), numa_mem_id() and cpu_to_mem() * defined in <linux/topology.h>. */ DEFINE_PER_CPU(int, _numa_mem_); /* Kernel "local memory" node */ EXPORT_PER_CPU_SYMBOL(_numa_mem_); #endif /* * 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 #ifdef CONFIG_MOVABLE_NODE [N_MEMORY] = { { [0] = 1UL } }, #endif [N_CPU] = { { [0] = 1UL } }, #endif /* NUMA */ }; EXPORT_SYMBOL(node_states); /* Protect totalram_pages and zone->managed_pages */ static DEFINE_SPINLOCK(managed_page_count_lock); unsigned long totalram_pages __read_mostly; unsigned long totalreserve_pages __read_mostly; /* * When calculating the number of globally allowed dirty pages, there * is a certain number of per-zone reserves that should not be * considered dirtyable memory. This is the sum of those reserves * over all existing zones that contribute dirtyable memory. */ unsigned long dirty_balance_reserve __read_mostly; int percpu_pagelist_fraction; gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK; #ifdef CONFIG_PM_SLEEP /* * The following functions are used by the suspend/hibernate code to temporarily * change gfp_allowed_mask in order to avoid using I/O during memory allocations * while devices are suspended. To avoid races with the suspend/hibernate code, * they should always be called with pm_mutex held (gfp_allowed_mask also should * only be modified with pm_mutex held, unless the suspend/hibernate code is * guaranteed not to run in parallel with that modification). */ static gfp_t saved_gfp_mask; void pm_restore_gfp_mask(void) { WARN_ON(!mutex_is_locked(&pm_mutex)); if (saved_gfp_mask) { gfp_allowed_mask = saved_gfp_mask; saved_gfp_mask = 0; } } void pm_restrict_gfp_mask(void) { WARN_ON(!mutex_is_locked(&pm_mutex)); WARN_ON(saved_gfp_mask); saved_gfp_mask = gfp_allowed_mask; gfp_allowed_mask &= ~GFP_IOFS; } bool pm_suspended_storage(void) { if ((gfp_allowed_mask & GFP_IOFS) == GFP_IOFS) return false; return true; } #endif /* CONFIG_PM_SLEEP */ #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; int user_min_free_kbytes; static unsigned long __meminitdata nr_kernel_pages; static unsigned long __meminitdata nr_all_pages; static unsigned long __meminitdata dma_reserve; #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP static unsigned long __meminitdata arch_zone_lowest_possible_pfn[MAX_NR_ZONES]; static unsigned long __meminitdata arch_zone_highest_possible_pfn[MAX_NR_ZONES]; 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_HAVE_MEMBLOCK_NODE_MAP */ #if MAX_NUMNODES > 1 int nr_node_ids __read_mostly = MAX_NUMNODES; int nr_online_nodes __read_mostly = 1; EXPORT_SYMBOL(nr_node_ids); EXPORT_SYMBOL(nr_online_nodes); #endif int page_group_by_mobility_disabled __read_mostly; void set_pageblock_migratetype(struct page *page, int migratetype) { if (unlikely(page_group_by_mobility_disabled)) migratetype = MIGRATE_UNMOVABLE; set_pageblock_flags_group(page, (unsigned long)migratetype, PB_migrate, PB_migrate_end); } bool oom_killer_disabled __read_mostly; #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); unsigned long sp, start_pfn; do { seq = zone_span_seqbegin(zone); start_pfn = zone->zone_start_pfn; sp = zone->spanned_pages; if (!zone_spans_pfn(zone, pfn)) ret = 1; } while (zone_span_seqretry(zone, seq)); if (ret) pr_err("page %lu outside zone [ %lu - %lu ]\n", pfn, start_pfn, start_pfn + sp); 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) { static unsigned long resume; static unsigned long nr_shown; static unsigned long nr_unshown; /* Don't complain about poisoned pages */ if (PageHWPoison(page)) { page_mapcount_reset(page); /* remove PageBuddy */ return; } /* * Allow a burst of 60 reports, then keep quiet for that minute; * or allow a steady drip of one report per second. */ if (nr_shown == 60) { if (time_before(jiffies, resume)) { nr_unshown++; goto out; } if (nr_unshown) { printk(KERN_ALERT "BUG: Bad page state: %lu messages suppressed\n", nr_unshown); nr_unshown = 0; } nr_shown = 0; } if (nr_shown++ == 0) resume = jiffies + 60 * HZ; printk(KERN_ALERT "BUG: Bad page state in process %s pfn:%05lx\n", current->comm, page_to_pfn(page)); dump_page(page); print_modules(); dump_stack(); out: /* Leave bad fields for debug, except PageBuddy could make trouble */ page_mapcount_reset(page); /* remove PageBuddy */ add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); } /* * 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 tail pages have their ->first_page * pointing at the head page. * * 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); set_page_count(p, 0); p->first_page = page; } } /* update __split_huge_page_refcount if you change this function */ static int destroy_compound_page(struct page *page, unsigned long order) { int i; int nr_pages = 1 << order; int bad = 0; if (unlikely(compound_order(page) != order)) { bad_page(page); bad++; } __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); bad++; } __ClearPageTail(p); } return bad; } 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); } #ifdef CONFIG_DEBUG_PAGEALLOC unsigned int _debug_guardpage_minorder; static int __init debug_guardpage_minorder_setup(char *buf) { unsigned long res; if (kstrtoul(buf, 10, &res) < 0 || res > MAX_ORDER / 2) { printk(KERN_ERR "Bad debug_guardpage_minorder value\n"); return 0; } _debug_guardpage_minorder = res; printk(KERN_INFO "Setting debug_guardpage_minorder to %lu\n", res); return 0; } __setup("debug_guardpage_minorder=", debug_guardpage_minorder_setup); static inline void set_page_guard_flag(struct page *page) { __set_bit(PAGE_DEBUG_FLAG_GUARD, &page->debug_flags); } static inline void clear_page_guard_flag(struct page *page) { __clear_bit(PAGE_DEBUG_FLAG_GUARD, &page->debug_flags); } #else static inline void set_page_guard_flag(struct page *page) { } static inline void clear_page_guard_flag(struct page *page) { } #endif 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 unsigned long __find_buddy_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 set ->_mapcount * PAGE_BUDDY_MAPCOUNT_VALUE. * Setting, clearing, and testing _mapcount PAGE_BUDDY_MAPCOUNT_VALUE 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 (page_is_guard(buddy) && page_order(buddy) == order) { VM_BUG_ON(page_count(buddy) != 0); return 1; } if (PageBuddy(buddy) && page_order(buddy) == order) { VM_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 _mapcount * PAGE_BUDDY_MAPCOUNT_VALUE. 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. * * -- nyc */ static inline void __free_one_page(struct page *page, struct zone *zone, unsigned int order, int migratetype) { unsigned long page_idx; unsigned long combined_idx; unsigned long uninitialized_var(buddy_idx); struct page *buddy; VM_BUG_ON(!zone_is_initialized(zone)); if (unlikely(PageCompound(page))) if (unlikely(destroy_compound_page(page, order))) return; VM_BUG_ON(migratetype == -1); page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1); VM_BUG_ON(page_idx & ((1 << order) - 1)); VM_BUG_ON(bad_range(zone, page)); while (order < MAX_ORDER-1) { buddy_idx = __find_buddy_index(page_idx, order); buddy = page + (buddy_idx - page_idx); if (!page_is_buddy(page, buddy, order)) break; /* * Our buddy is free or it is CONFIG_DEBUG_PAGEALLOC guard page, * merge with it and move up one order. */ if (page_is_guard(buddy)) { clear_page_guard_flag(buddy); set_page_private(page, 0); __mod_zone_freepage_state(zone, 1 << order, migratetype); } else { list_del(&buddy->lru); zone->free_area[order].nr_free--; rmv_page_order(buddy); } combined_idx = buddy_idx & page_idx; page = page + (combined_idx - page_idx); page_idx = combined_idx; order++; } set_page_order(page, order); /* * If this is not the largest possible page, check if the buddy * of the next-highest order is free. If it is, it's possible * that pages are being freed that will coalesce soon. In case, * that is happening, add the free page to the tail of the list * so it's less likely to be used soon and more likely to be merged * as a higher order page */ if ((order < MAX_ORDER-2) && pfn_valid_within(page_to_pfn(buddy))) { struct page *higher_page, *higher_buddy; combined_idx = buddy_idx & page_idx; higher_page = page + (combined_idx - page_idx); buddy_idx = __find_buddy_index(combined_idx, order + 1); higher_buddy = higher_page + (buddy_idx - combined_idx); if (page_is_buddy(higher_page, higher_buddy, order + 1)) { list_add_tail(&page->lru, &zone->free_area[order].free_list[migratetype]); goto out; } } list_add(&page->lru, &zone->free_area[order].free_list[migratetype]); out: zone->free_area[order].nr_free++; } static inline int free_pages_check(struct page *page) { if (unlikely(page_mapcount(page) | (page->mapping != NULL) | (atomic_read(&page->_count) != 0) | (page->flags & PAGE_FLAGS_CHECK_AT_FREE) | (mem_cgroup_bad_page_check(page)))) { bad_page(page); return 1; } page_cpupid_reset_last(page); if (page->flags & PAGE_FLAGS_CHECK_AT_PREP) page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP; return 0; } /* * Frees a number of pages from the PCP lists * 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_pcppages_bulk(struct zone *zone, int count, struct per_cpu_pages *pcp) { int migratetype = 0; int batch_free = 0; int to_free = count; spin_lock(&zone->lock); zone->pages_scanned = 0; while (to_free) { struct page *page; struct list_head *list; /* * Remove pages from lists in a round-robin fashion. A * batch_free count is maintained that is incremented when an * empty list is encountered. This is so more pages are freed * off fuller lists instead of spinning excessively around empty * lists */ do { batch_free++; if (++migratetype == MIGRATE_PCPTYPES) migratetype = 0; list = &pcp->lists[migratetype]; } while (list_empty(list)); /* This is the only non-empty list. Free them all. */ if (batch_free == MIGRATE_PCPTYPES) batch_free = to_free; do { int mt; /* migratetype of the to-be-freed page */ page = list_entry(list->prev, struct page, lru); /* must delete as __free_one_page list manipulates */ list_del(&page->lru); mt = get_freepage_migratetype(page); /* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */ __free_one_page(page, zone, 0, mt); trace_mm_page_pcpu_drain(page, 0, mt); if (likely(!is_migrate_isolate_page(page))) { __mod_zone_page_state(zone, NR_FREE_PAGES, 1); if (is_migrate_cma(mt)) __mod_zone_page_state(zone, NR_FREE_CMA_PAGES, 1); } } while (--to_free && --batch_free && !list_empty(list)); } spin_unlock(&zone->lock); } static void free_one_page(struct zone *zone, struct page *page, int order, int migratetype) { spin_lock(&zone->lock); zone->pages_scanned = 0; __free_one_page(page, zone, order, migratetype); if (unlikely(!is_migrate_isolate(migratetype))) __mod_zone_freepage_state(zone, 1 << order, migratetype); spin_unlock(&zone->lock); } static bool free_pages_prepare(struct page *page, unsigned int order) { int i; int bad = 0; trace_mm_page_free(page, order); kmemcheck_free_shadow(page, order); if (PageAnon(page)) page->mapping = NULL; for (i = 0; i < (1 << order); i++) bad += free_pages_check(page + i); if (bad) return false; 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); return true; } static void __free_pages_ok(struct page *page, unsigned int order) { unsigned long flags; int migratetype; if (!free_pages_prepare(page, order)) return; local_irq_save(flags); __count_vm_events(PGFREE, 1 << order); migratetype = get_pageblock_migratetype(page); set_freepage_migratetype(page, migratetype); free_one_page(page_zone(page), page, order, migratetype); local_irq_restore(flags); } void __init __free_pages_bootmem(struct page *page, unsigned int order) { unsigned int nr_pages = 1 << order; struct page *p = page; unsigned int loop; prefetchw(p); for (loop = 0; loop < (nr_pages - 1); loop++, p++) { prefetchw(p + 1); __ClearPageReserved(p); set_page_count(p, 0); } __ClearPageReserved(p); set_page_count(p, 0); page_zone(page)->managed_pages += nr_pages; set_page_refcounted(page); __free_pages(page, order); } #ifdef CONFIG_CMA /* Free whole pageblock and set its migration type to MIGRATE_CMA. */ void __init init_cma_reserved_pageblock(struct page *page) { unsigned i = pageblock_nr_pages; struct page *p = page; do { __ClearPageReserved(p); set_page_count(p, 0); } while (++p, --i); set_page_refcounted(page); set_pageblock_migratetype(page, MIGRATE_CMA); __free_pages(page, pageblock_order); adjust_managed_page_count(page, pageblock_nr_pages); } #endif /* * 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. * * -- nyc */ 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])); #ifdef CONFIG_DEBUG_PAGEALLOC if (high < debug_guardpage_minorder()) { /* * Mark as guard pages (or page), that will allow to * merge back to allocator when buddy will be freed. * Corresponding page table entries will not be touched, * pages will stay not present in virtual address space */ INIT_LIST_HEAD(&page[size].lru); set_page_guard_flag(&page[size]); set_page_private(&page[size], high); /* Guard pages are not available for any usage */ __mod_zone_freepage_state(zone, -(1 << high), migratetype); continue; } #endif 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 inline int check_new_page(struct page *page) { if (unlikely(page_mapcount(page) | (page->mapping != NULL) | (atomic_read(&page->_count) != 0) | (page->flags & PAGE_FLAGS_CHECK_AT_PREP) | (mem_cgroup_bad_page_check(page)))) { bad_page(page); return 1; } return 0; } static int prep_new_page(struct page *page, int order, gfp_t gfp_flags) { int i; for (i = 0; i < (1 << order); i++) { struct page *p = page + i; if (unlikely(check_new_page(p))) return 1; } 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 inline 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--; 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][4] = { [MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE }, [MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE }, #ifdef CONFIG_CMA [MIGRATE_MOVABLE] = { MIGRATE_CMA, MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE }, [MIGRATE_CMA] = { MIGRATE_RESERVE }, /* Never used */ #else [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE }, #endif [MIGRATE_RESERVE] = { MIGRATE_RESERVE }, /* Never used */ #ifdef CONFIG_MEMORY_ISOLATION [MIGRATE_ISOLATE] = { MIGRATE_RESERVE }, /* Never used */ #endif }; /* * 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() */ 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_move(&page->lru, &zone->free_area[order].free_list[migratetype]); set_freepage_migratetype(page, migratetype); page += 1 << order; pages_moved += 1 << order; } return pages_moved; } 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 (!zone_spans_pfn(zone, start_pfn)) start_page = page; if (!zone_spans_pfn(zone, end_pfn)) return 0; return move_freepages(zone, start_page, end_page, migratetype); } static void change_pageblock_range(struct page *pageblock_page, int start_order, int migratetype) { int nr_pageblocks = 1 << (start_order - pageblock_order); while (nr_pageblocks--) { set_pageblock_migratetype(pageblock_page, migratetype); pageblock_page += pageblock_nr_pages; } } /* * 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 aggressive about taking ownership of free pages. * * On the other hand, never change migration type of MIGRATE_CMA pageblocks * nor move CMA pages to different free lists. We don't want unmovable pages * to be allocated from MIGRATE_CMA areas. * * Returns the new migratetype of the pageblock (or the same old migratetype * if it was unchanged). */ static int try_to_steal_freepages(struct zone *zone, struct page *page, int start_type, int fallback_type) { int current_order = page_order(page); if (is_migrate_cma(fallback_type)) return fallback_type; /* Take ownership for orders >= pageblock_order */ if (current_order >= pageblock_order) { change_pageblock_range(page, current_order, start_type); return start_type; } if (current_order >= pageblock_order / 2 || start_type == MIGRATE_RECLAIMABLE || page_group_by_mobility_disabled) { int pages; pages = move_freepages_block(zone, page, start_type); /* Claim the whole block if over half of it is free */ if (pages >= (1 << (pageblock_order-1)) || page_group_by_mobility_disabled) { set_pageblock_migratetype(page, start_type); return start_type; } } return fallback_type; } /* Remove an element from the buddy allocator from the fallback list */ static inline struct page * __rmqueue_fallback(struct zone *zone, int order, int start_migratetype) { struct free_area *area; int current_order; struct page *page; int migratetype, new_type, 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++) { migratetype = fallbacks[start_migratetype][i]; /* MIGRATE_RESERVE handled later if necessary */ if (migratetype == MIGRATE_RESERVE) break; 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--; new_type = try_to_steal_freepages(zone, page, start_migratetype, migratetype); /* Remove the page from the freelists */ list_del(&page->lru); rmv_page_order(page); /* * Borrow the excess buddy pages as well, irrespective * of whether we stole freepages, or took ownership of * the pageblock or not. * * Exception: When borrowing from MIGRATE_CMA, release * the excess buddy pages to CMA itself. */ expand(zone, page, order, current_order, area, is_migrate_cma(migratetype) ? migratetype : start_migratetype); trace_mm_page_alloc_extfrag(page, order, current_order, start_migratetype, migratetype, new_type == start_migratetype); return page; } } return NULL; } /* * 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; retry_reserve: page = __rmqueue_smallest(zone, order, migratetype); if (unlikely(!page) && migratetype != MIGRATE_RESERVE) { page = __rmqueue_fallback(zone, order, migratetype); /* * Use MIGRATE_RESERVE rather than fail an allocation. goto * is used because __rmqueue_smallest is an inline function * and we want just one call site */ if (!page) { migratetype = MIGRATE_RESERVE; goto retry_reserve; } } trace_mm_page_alloc_zone_locked(page, 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 cold) { int mt = migratetype, 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. */ if (likely(cold == 0)) list_add(&page->lru, list); else list_add_tail(&page->lru, list); if (IS_ENABLED(CONFIG_CMA)) { mt = get_pageblock_migratetype(page); if (!is_migrate_cma(mt) && !is_migrate_isolate(mt)) mt = migratetype; } set_freepage_migratetype(page, mt); list = &page->lru; if (is_migrate_cma(mt)) __mod_zone_page_state(zone, NR_FREE_CMA_PAGES, -(1 << order)); } __mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order)); 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; unsigned long batch; local_irq_save(flags); batch = ACCESS_ONCE(pcp->batch); if (pcp->count >= batch) to_drain = batch; else to_drain = pcp->count; if (to_drain > 0) { free_pcppages_bulk(zone, to_drain, pcp); 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_populated_zone(zone) { struct per_cpu_pageset *pset; struct per_cpu_pages *pcp; local_irq_save(flags); pset = per_cpu_ptr(zone->pageset, cpu); pcp = &pset->pcp; if (pcp->count) { free_pcppages_bulk(zone, pcp->count, pcp); 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. * * Note that this code is protected against sending an IPI to an offline * CPU but does not guarantee sending an IPI to newly hotplugged CPUs: * on_each_cpu_mask() blocks hotplug and won't talk to offlined CPUs but * nothing keeps CPUs from showing up after we populated the cpumask and * before the call to on_each_cpu_mask(). */ void drain_all_pages(void) { int cpu; struct per_cpu_pageset *pcp; struct zone *zone; /* * Allocate in the BSS so we wont require allocation in * direct reclaim path for CONFIG_CPUMASK_OFFSTACK=y */ static cpumask_t cpus_with_pcps; /* * We don't care about racing with CPU hotplug event * as offline notification will cause the notified * cpu to drain that CPU pcps and on_each_cpu_mask * disables preemption as part of its processing */ for_each_online_cpu(cpu) { bool has_pcps = false; for_each_populated_zone(zone) { pcp = per_cpu_ptr(zone->pageset, cpu); if (pcp->pcp.count) { has_pcps = true; break; } } if (has_pcps) cpumask_set_cpu(cpu, &cpus_with_pcps); else cpumask_clear_cpu(cpu, &cpus_with_pcps); } on_each_cpu_mask(&cpus_with_pcps, 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_is_empty(zone)) return; spin_lock_irqsave(&zone->lock, flags); max_zone_pfn = zone_end_pfn(zone); 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 * cold == 1 ? free a cold page : free a hot page */ void free_hot_cold_page(struct page *page, int cold) { struct zone *zone = page_zone(page); struct per_cpu_pages *pcp; unsigned long flags; int migratetype; if (!free_pages_prepare(page, 0)) return; migratetype = get_pageblock_migratetype(page); set_freepage_migratetype(page, migratetype); local_irq_save(flags); __count_vm_event(PGFREE); /* * We only track unmovable, reclaimable and movable on pcp lists. * Free ISOLATE pages back to the allocator because they are being * offlined but treat RESERVE as movable pages so we can get those * areas back if necessary. Otherwise, we may have to free * excessively into the page allocator */ if (migratetype >= MIGRATE_PCPTYPES) { if (unlikely(is_migrate_isolate(migratetype))) { free_one_page(zone, page, 0, migratetype); goto out; } migratetype = MIGRATE_MOVABLE; } pcp = &this_cpu_ptr(zone->pageset)->pcp; if (cold) list_add_tail(&page->lru, &pcp->lists[migratetype]); else list_add(&page->lru, &pcp->lists[migratetype]); pcp->count++; if (pcp->count >= pcp->high) { unsigned long batch = ACCESS_ONCE(pcp->batch); free_pcppages_bulk(zone, batch, pcp); pcp->count -= batch; } out: local_irq_restore(flags); } /* * Free a list of 0-order pages */ void free_hot_cold_page_list(struct list_head *list, int cold) { struct page *page, *next; list_for_each_entry_safe(page, next, list, lru) { trace_mm_page_free_batched(page, cold); free_hot_cold_page(page, cold); } } /* * 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)); #ifdef CONFIG_KMEMCHECK /* * Split shadow pages too, because free(page[0]) would * otherwise free the whole shadow. */ if (kmemcheck_page_is_tracked(page)) split_page(virt_to_page(page[0].shadow), order); #endif for (i = 1; i < (1 << order); i++) set_page_refcounted(page + i); } EXPORT_SYMBOL_GPL(split_page); static int __isolate_free_page(struct page *page, unsigned int order) { unsigned long watermark; struct zone *zone; int mt; BUG_ON(!PageBuddy(page)); zone = page_zone(page); mt = get_pageblock_migratetype(page); if (!is_migrate_isolate(mt)) { /* Obey watermarks as if the page was being allocated */ watermark = low_wmark_pages(zone) + (1 << order); if (!zone_watermark_ok(zone, 0, watermark, 0, 0)) return 0; __mod_zone_freepage_state(zone, -(1UL << order), mt); } /* Remove page from free list */ list_del(&page->lru); zone->free_area[order].nr_free--; rmv_page_order(page); /* Set the pageblock if the isolated page is at least a pageblock */ if (order >= pageblock_order - 1) { struct page *endpage = page + (1 << order) - 1; for (; page < endpage; page += pageblock_nr_pages) { int mt = get_pageblock_migratetype(page); if (!is_migrate_isolate(mt) && !is_migrate_cma(mt)) set_pageblock_migratetype(page, MIGRATE_MOVABLE); } } return 1UL << order; } /* * Similar to split_page except the page is already free. As this is only * being used for migration, the migratetype of the block also changes. * As this is called with interrupts disabled, the caller is responsible * for calling arch_alloc_page() and kernel_map_page() after interrupts * are enabled. * * Note: this is probably too low level an operation for use in drivers. * Please consult with lkml before using this in your driver. */ int split_free_page(struct page *page) { unsigned int order; int nr_pages; order = page_order(page); nr_pages = __isolate_free_page(page, order); if (!nr_pages) return 0; /* Split into individual pages */ set_page_refcounted(page); split_page(page, order); return nr_pages; } /* * 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 inline struct page *buffered_rmqueue(struct zone *preferred_zone, struct zone *zone, int order, gfp_t gfp_flags, int migratetype) { unsigned long flags; struct page *page; int cold = !!(gfp_flags & __GFP_COLD); again: if (likely(order == 0)) { struct per_cpu_pages *pcp; struct list_head *list; local_irq_save(flags); pcp = &this_cpu_ptr(zone->pageset)->pcp; list = &pcp->lists[migratetype]; if (list_empty(list)) { pcp->count += rmqueue_bulk(zone, 0, pcp->batch, list, migratetype, cold); if (unlikely(list_empty(list))) goto failed; } if (cold) page = list_entry(list->prev, struct page, lru); else page = list_entry(list->next, struct page, lru); list_del(&page->lru); pcp->count--; } else { if (unlikely(gfp_flags & __GFP_NOFAIL)) { /* * __GFP_NOFAIL is not to be used in new code. * * All __GFP_NOFAIL callers should be fixed so that they * properly detect and handle allocation failures. * * We most definitely don't want callers attempting to * allocate greater than order-1 page units with * __GFP_NOFAIL. */ WARN_ON_ONCE(order > 1); } spin_lock_irqsave(&zone->lock, flags); page = __rmqueue(zone, order, migratetype); spin_unlock(&zone->lock); if (!page) goto failed; __mod_zone_freepage_state(zone, -(1 << order), get_pageblock_migratetype(page)); } __mod_zone_page_state(zone, NR_ALLOC_BATCH, -(1 << order)); __count_zone_vm_events(PGALLOC, zone, 1 << order); zone_statistics(preferred_zone, zone, gfp_flags); local_irq_restore(flags); VM_BUG_ON(bad_range(zone, page)); if (prep_new_page(page, order, gfp_flags)) goto again; return page; failed: local_irq_restore(flags); return NULL; } #ifdef CONFIG_FAIL_PAGE_ALLOC static struct { struct fault_attr attr; u32 ignore_gfp_highmem; u32 ignore_gfp_wait; u32 min_order; } 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 bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) { if (order < fail_page_alloc.min_order) return false; if (gfp_mask & __GFP_NOFAIL) return false; if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM)) return false; if (fail_page_alloc.ignore_gfp_wait && (gfp_mask & __GFP_WAIT)) return false; return should_fail(&fail_page_alloc.attr, 1 << order); } #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS static int __init fail_page_alloc_debugfs(void) { umode_t mode = S_IFREG | S_IRUSR | S_IWUSR; struct dentry *dir; dir = fault_create_debugfs_attr("fail_page_alloc", NULL, &fail_page_alloc.attr); if (IS_ERR(dir)) return PTR_ERR(dir); if (!debugfs_create_bool("ignore-gfp-wait", mode, dir, &fail_page_alloc.ignore_gfp_wait)) goto fail; if (!debugfs_create_bool("ignore-gfp-highmem", mode, dir, &fail_page_alloc.ignore_gfp_highmem)) goto fail; if (!debugfs_create_u32("min-order", mode, dir, &fail_page_alloc.min_order)) goto fail; return 0; fail: debugfs_remove_recursive(dir); return -ENOMEM; } late_initcall(fail_page_alloc_debugfs); #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */ #else /* CONFIG_FAIL_PAGE_ALLOC */ static inline bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) { return false; } #endif /* CONFIG_FAIL_PAGE_ALLOC */ /* * Return true if free pages are above 'mark'. This takes into account the order * of the allocation. */ static bool __zone_watermark_ok(struct zone *z, int order, unsigned long mark, int classzone_idx, int alloc_flags, long free_pages) { /* free_pages my go negative - that's OK */ long min = mark; long lowmem_reserve = z->lowmem_reserve[classzone_idx]; int o; long free_cma = 0; free_pages -= (1 << order) - 1; if (alloc_flags & ALLOC_HIGH) min -= min / 2; if (alloc_flags & ALLOC_HARDER) min -= min / 4; #ifdef CONFIG_CMA /* If allocation can't use CMA areas don't use free CMA pages */ if (!(alloc_flags & ALLOC_CMA)) free_cma = zone_page_state(z, NR_FREE_CMA_PAGES); #endif if (free_pages - free_cma <= min + lowmem_reserve) return false; 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 false; } return true; } bool zone_watermark_ok(struct zone *z, int order, unsigned long mark, int classzone_idx, int alloc_flags) { return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags, zone_page_state(z, NR_FREE_PAGES)); } bool zone_watermark_ok_safe(struct zone *z, int order, unsigned long mark, int classzone_idx, int alloc_flags) { long free_pages = zone_page_state(z, NR_FREE_PAGES); if (z->percpu_drift_mark && free_pages < z->percpu_drift_mark) free_pages = zone_page_state_snapshot(z, NR_FREE_PAGES); return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags, free_pages); } #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_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_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); } /* * clear all zones full, called after direct reclaim makes progress so that * a zone that was recently full is not skipped over for up to a second */ static void zlc_clear_zones_full(struct zonelist *zonelist) { struct zonelist_cache *zlc; /* cached zonelist speedup info */ zlc = zonelist->zlcache_ptr; if (!zlc) return; bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST); } static bool zone_local(struct zone *local_zone, struct zone *zone) { return node_distance(local_zone->node, zone->node) == LOCAL_DISTANCE; } static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone) { return node_isset(local_zone->node, zone->zone_pgdat->reclaim_nodes); } static void __paginginit init_zone_allows_reclaim(int nid) { int i; for_each_online_node(i) if (node_distance(nid, i) <= RECLAIM_DISTANCE) node_set(i, NODE_DATA(nid)->reclaim_nodes); else zone_reclaim_mode = 1; } #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) { } static void zlc_clear_zones_full(struct zonelist *zonelist) { } static bool zone_local(struct zone *local_zone, struct zone *zone) { return true; } static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone) { return true; } static inline void init_zone_allows_reclaim(int nid) { } #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 zone *preferred_zone, int migratetype) { struct zoneref *z; struct page *page = NULL; int classzone_idx; struct zone *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 */ classzone_idx = zone_idx(preferred_zone); zonelist_scan: /* * Scan zonelist, looking for a zone with enough free. * See also __cpuset_node_allowed_softwall() comment in kernel/cpuset.c. */ for_each_zone_zonelist_nodemask(zone, z, zonelist, high_zoneidx, nodemask) { unsigned long mark; if (IS_ENABLED(CONFIG_NUMA) && zlc_active && !zlc_zone_worth_trying(zonelist, z, allowednodes)) continue; if ((alloc_flags & ALLOC_CPUSET) && !cpuset_zone_allowed_softwall(zone, gfp_mask)) continue; BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK); if (unlikely(alloc_flags & ALLOC_NO_WATERMARKS)) goto try_this_zone; /* * Distribute pages in proportion to the individual * zone size to ensure fair page aging. The zone a * page was allocated in should have no effect on the * time the page has in memory before being reclaimed. * * When zone_reclaim_mode is enabled, try to stay in * local zones in the fastpath. If that fails, the * slowpath is entered, which will do another pass * starting with the local zones, but ultimately fall * back to remote zones that do not partake in the * fairness round-robin cycle of this zonelist. */ if (alloc_flags & ALLOC_WMARK_LOW) { if (zone_page_state(zone, NR_ALLOC_BATCH) <= 0) continue; if (zone_reclaim_mode && !zone_local(preferred_zone, zone)) continue; } /* * When allocating a page cache page for writing, we * want to get it from a zone that is within its dirty * limit, such that no single zone holds more than its * proportional share of globally allowed dirty pages. * The dirty limits take into account the zone's * lowmem reserves and high watermark so that kswapd * should be able to balance it without having to * write pages from its LRU list. * * This may look like it could increase pressure on * lower zones by failing allocations in higher zones * before they are full. But the pages that do spill * over are limited as the lower zones are protected * by this very same mechanism. It should not become * a practical burden to them. * * XXX: For now, allow allocations to potentially * exceed the per-zone dirty limit in the slowpath * (ALLOC_WMARK_LOW unset) before going into reclaim, * which is important when on a NUMA setup the allowed * zones are together not big enough to reach the * global limit. The proper fix for these situations * will require awareness of zones in the * dirty-throttling and the flusher threads. */ if ((alloc_flags & ALLOC_WMARK_LOW) && (gfp_mask & __GFP_WRITE) && !zone_dirty_ok(zone)) goto this_zone_full; mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK]; if (!zone_watermark_ok(zone, order, mark, classzone_idx, alloc_flags)) { int ret; if (IS_ENABLED(CONFIG_NUMA) && !did_zlc_setup && nr_online_nodes > 1) { /* * we do zlc_setup if there are multiple nodes * and before considering the first zone allowed * by the cpuset. */ allowednodes = zlc_setup(zonelist, alloc_flags); zlc_active = 1; did_zlc_setup = 1; } if (zone_reclaim_mode == 0 || !zone_allows_reclaim(preferred_zone, zone)) goto this_zone_full; /* * As we may have just activated ZLC, check if the first * eligible zone has failed zone_reclaim recently. */ if (IS_ENABLED(CONFIG_NUMA) && zlc_active && !zlc_zone_worth_trying(zonelist, z, allowednodes)) continue; ret = zone_reclaim(zone, gfp_mask, order); switch (ret) { case ZONE_RECLAIM_NOSCAN: /* did not scan */ continue; case ZONE_RECLAIM_FULL: /* scanned but unreclaimable */ continue; default: /* did we reclaim enough */ if (zone_watermark_ok(zone, order, mark, classzone_idx, alloc_flags)) goto try_this_zone; /* * Failed to reclaim enough to meet watermark. * Only mark the zone full if checking the min * watermark or if we failed to reclaim just * 1<<order pages or else the page allocator * fastpath will prematurely mark zones full * when the watermark is between the low and * min watermarks. */ if (((alloc_flags & ALLOC_WMARK_MASK) == ALLOC_WMARK_MIN) || ret == ZONE_RECLAIM_SOME) goto this_zone_full; continue; } } try_this_zone: page = buffered_rmqueue(preferred_zone, zone, order, gfp_mask, migratetype); if (page) break; this_zone_full: if (IS_ENABLED(CONFIG_NUMA)) zlc_mark_zone_full(zonelist, z); } if (unlikely(IS_ENABLED(CONFIG_NUMA) && page == NULL && zlc_active)) { /* Disable zlc cache for second zonelist scan */ zlc_active = 0; goto zonelist_scan; } if (page) /* * page->pfmemalloc is set when ALLOC_NO_WATERMARKS was * necessary to allocate the page. The expectation is * that the caller is taking steps that will free more * memory. The caller should avoid the page being used * for !PFMEMALLOC purposes. */ page->pfmemalloc = !!(alloc_flags & ALLOC_NO_WATERMARKS); return page; } /* * Large machines with many possible nodes should not always dump per-node * meminfo in irq context. */ static inline bool should_suppress_show_mem(void) { bool ret = false; #if NODES_SHIFT > 8 ret = in_interrupt(); #endif return ret; } static DEFINE_RATELIMIT_STATE(nopage_rs, DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST); void warn_alloc_failed(gfp_t gfp_mask, int order, const char *fmt, ...) { unsigned int filter = SHOW_MEM_FILTER_NODES; if ((gfp_mask & __GFP_NOWARN) || !__ratelimit(&nopage_rs) || debug_guardpage_minorder() > 0) return; /* * Walking all memory to count page types is very expensive and should * be inhibited in non-blockable contexts. */ if (!(gfp_mask & __GFP_WAIT)) filter |= SHOW_MEM_FILTER_PAGE_COUNT; /* * This documents exceptions given to allocations in certain * contexts that are allowed to allocate outside current's set * of allowed nodes. */ if (!(gfp_mask & __GFP_NOMEMALLOC)) if (test_thread_flag(TIF_MEMDIE) || (current->flags & (PF_MEMALLOC | PF_EXITING))) filter &= ~SHOW_MEM_FILTER_NODES; if (in_interrupt() || !(gfp_mask & __GFP_WAIT)) filter &= ~SHOW_MEM_FILTER_NODES; if (fmt) { struct va_format vaf; va_list args; va_start(args, fmt); vaf.fmt = fmt; vaf.va = &args; pr_warn("%pV", &vaf); va_end(args); } pr_warn("%s: page allocation failure: order:%d, mode:0x%x\n", current->comm, order, gfp_mask); dump_stack(); if (!should_suppress_show_mem()) show_mem(filter); } static inline int should_alloc_retry(gfp_t gfp_mask, unsigned int order, unsigned long did_some_progress, unsigned long pages_reclaimed) { /* Do not loop if specifically requested */ if (gfp_mask & __GFP_NORETRY) return 0; /* Always retry if specifically requested */ if (gfp_mask & __GFP_NOFAIL) return 1; /* * Suspend converts GFP_KERNEL to __GFP_WAIT which can prevent reclaim * making forward progress without invoking OOM. Suspend also disables * storage devices so kswapd will not help. Bail if we are suspending. */ if (!did_some_progress && pm_suspended_storage()) return 0; /* * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER * means __GFP_NOFAIL, but that may not be true in other * implementations. */ if (order <= PAGE_ALLOC_COSTLY_ORDER) return 1; /* * 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. */ if (gfp_mask & __GFP_REPEAT && pages_reclaimed < (1 << order)) return 1; return 0; } static inline struct page * __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order, struct zonelist *zonelist, enum zone_type high_zoneidx, nodemask_t *nodemask, struct zone *preferred_zone, int migratetype) { struct page *page; /* Acquire the OOM killer lock for the zones in zonelist */ if (!try_set_zonelist_oom(zonelist, gfp_mask)) { schedule_timeout_uninterruptible(1); return NULL; } /* * 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, preferred_zone, migratetype); if (page) goto out; if (!(gfp_mask & __GFP_NOFAIL)) { /* The OOM killer will not help higher order allocs */ if (order > PAGE_ALLOC_COSTLY_ORDER) goto out; /* The OOM killer does not needlessly kill tasks for lowmem */ if (high_zoneidx < ZONE_NORMAL) goto out; /* * GFP_THISNODE contains __GFP_NORETRY and we never hit this. * Sanity check for bare calls of __GFP_THISNODE, not real OOM. * The caller should handle page allocation failure by itself if * it specifies __GFP_THISNODE. * Note: Hugepage uses it but will hit PAGE_ALLOC_COSTLY_ORDER. */ if (gfp_mask & __GFP_THISNODE) goto out; } /* Exhausted what can be done so it's blamo time */ out_of_memory(zonelist, gfp_mask, order, nodemask, false); out: clear_zonelist_oom(zonelist, gfp_mask); return page; } #ifdef CONFIG_COMPACTION /* Try memory compaction for high-order allocations before reclaim */ static struct page * __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, struct zonelist *zonelist, enum zone_type high_zoneidx, nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone, int migratetype, bool sync_migration, bool *contended_compaction, bool *deferred_compaction, unsigned long *did_some_progress) { if (!order) return NULL; if (compaction_deferred(preferred_zone, order)) { *deferred_compaction = true; return NULL; } current->flags |= PF_MEMALLOC; *did_some_progress = try_to_compact_pages(zonelist, order, gfp_mask, nodemask, sync_migration, contended_compaction); current->flags &= ~PF_MEMALLOC; if (*did_some_progress != COMPACT_SKIPPED) { struct page *page; /* Page migration frees to the PCP lists but we want merging */ drain_pages(get_cpu()); put_cpu(); page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist, high_zoneidx, alloc_flags & ~ALLOC_NO_WATERMARKS, preferred_zone, migratetype); if (page) { preferred_zone->compact_blockskip_flush = false; preferred_zone->compact_considered = 0; preferred_zone->compact_defer_shift = 0; if (order >= preferred_zone->compact_order_failed) preferred_zone->compact_order_failed = order + 1; count_vm_event(COMPACTSUCCESS); return page; } /* * It's bad if compaction run occurs and fails. * The most likely reason is that pages exist, * but not enough to satisfy watermarks. */ count_vm_event(COMPACTFAIL); /* * As async compaction considers a subset of pageblocks, only * defer if the failure was a sync compaction failure. */ if (sync_migration) defer_compaction(preferred_zone, order); cond_resched(); } return NULL; } #else static inline struct page * __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, struct zonelist *zonelist, enum zone_type high_zoneidx, nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone, int migratetype, bool sync_migration, bool *contended_compaction, bool *deferred_compaction, unsigned long *did_some_progress) { return NULL; } #endif /* CONFIG_COMPACTION */ /* Perform direct synchronous page reclaim */ static int __perform_reclaim(gfp_t gfp_mask, unsigned int order, struct zonelist *zonelist, nodemask_t *nodemask) { struct reclaim_state reclaim_state; int progress; cond_resched(); /* We now go into synchronous reclaim */ cpuset_memory_pressure_bump(); current->flags |= PF_MEMALLOC; lockdep_set_current_reclaim_state(gfp_mask); reclaim_state.reclaimed_slab = 0; current->reclaim_state = &reclaim_state; progress = try_to_free_pages(zonelist, order, gfp_mask, nodemask); current->reclaim_state = NULL; lockdep_clear_current_reclaim_state(); current->flags &= ~PF_MEMALLOC; cond_resched(); return progress; } /* The really slow allocator path where we enter direct reclaim */ static inline struct page * __alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order, struct zonelist *zonelist, enum zone_type high_zoneidx, nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone, int migratetype, unsigned long *did_some_progress) { struct page *page = NULL; bool drained = false; *did_some_progress = __perform_reclaim(gfp_mask, order, zonelist, nodemask); if (unlikely(!(*did_some_progress))) return NULL; /* After successful reclaim, reconsider all zones for allocation */ if (IS_ENABLED(CONFIG_NUMA)) zlc_clear_zones_full(zonelist); retry: page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist, high_zoneidx, alloc_flags & ~ALLOC_NO_WATERMARKS, preferred_zone, migratetype); /* * If an allocation failed after direct reclaim, it could be because * pages are pinned on the per-cpu lists. Drain them and try again */ if (!page && !drained) { drain_all_pages(); drained = true; goto retry; } return page; } /* * This is called in the allocator slow-path if the allocation request is of * sufficient urgency to ignore watermarks and take other desperate measures */ static inline struct page * __alloc_pages_high_priority(gfp_t gfp_mask, unsigned int order, struct zonelist *zonelist, enum zone_type high_zoneidx, nodemask_t *nodemask, struct zone *preferred_zone, int migratetype) { struct page *page; do { page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist, high_zoneidx, ALLOC_NO_WATERMARKS, preferred_zone, migratetype); if (!page && gfp_mask & __GFP_NOFAIL) wait_iff_congested(preferred_zone, BLK_RW_ASYNC, HZ/50); } while (!page && (gfp_mask & __GFP_NOFAIL)); return page; } static void prepare_slowpath(gfp_t gfp_mask, unsigned int order, struct zonelist *zonelist, enum zone_type high_zoneidx, struct zone *preferred_zone) { struct zoneref *z; struct zone *zone; for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) { if (!(gfp_mask & __GFP_NO_KSWAPD)) wakeup_kswapd(zone, order, zone_idx(preferred_zone)); /* * Only reset the batches of zones that were actually * considered in the fast path, we don't want to * thrash fairness information for zones that are not * actually part of this zonelist's round-robin cycle. */ if (zone_reclaim_mode && !zone_local(preferred_zone, zone)) continue; mod_zone_page_state(zone, NR_ALLOC_BATCH, high_wmark_pages(zone) - low_wmark_pages(zone) - zone_page_state(zone, NR_ALLOC_BATCH)); } } static inline int gfp_to_alloc_flags(gfp_t gfp_mask) { int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET; const gfp_t wait = gfp_mask & __GFP_WAIT; /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */ BUILD_BUG_ON(__GFP_HIGH != (__force gfp_t) ALLOC_HIGH); /* * 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 |= (__force int) (gfp_mask & __GFP_HIGH); if (!wait) { /* * Not worth trying to allocate harder for * __GFP_NOMEMALLOC even if it can't schedule. */ if (!(gfp_mask & __GFP_NOMEMALLOC)) alloc_flags |= ALLOC_HARDER; /* * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc. * See also cpuset_zone_allowed() comment in kernel/cpuset.c. */ alloc_flags &= ~ALLOC_CPUSET; } else if (unlikely(rt_task(current)) && !in_interrupt()) alloc_flags |= ALLOC_HARDER; if (likely(!(gfp_mask & __GFP_NOMEMALLOC))) { if (gfp_mask & __GFP_MEMALLOC) alloc_flags |= ALLOC_NO_WATERMARKS; else if (in_serving_softirq() && (current->flags & PF_MEMALLOC)) alloc_flags |= ALLOC_NO_WATERMARKS; else if (!in_interrupt() && ((current->flags & PF_MEMALLOC) || unlikely(test_thread_flag(TIF_MEMDIE)))) alloc_flags |= ALLOC_NO_WATERMARKS; } #ifdef CONFIG_CMA if (allocflags_to_migratetype(gfp_mask) == MIGRATE_MOVABLE) alloc_flags |= ALLOC_CMA; #endif return alloc_flags; } bool gfp_pfmemalloc_allowed(gfp_t gfp_mask) { return !!(gfp_to_alloc_flags(gfp_mask) & ALLOC_NO_WATERMARKS); } static inline struct page * __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, struct zonelist *zonelist, enum zone_type high_zoneidx, nodemask_t *nodemask, struct zone *preferred_zone, int migratetype) { const gfp_t wait = gfp_mask & __GFP_WAIT; struct page *page = NULL; int alloc_flags; unsigned long pages_reclaimed = 0; unsigned long did_some_progress; bool sync_migration = false; bool deferred_compaction = false; bool contended_compaction = false; /* * In the slowpath, we sanity check order to avoid ever trying to * reclaim >= MAX_ORDER areas which will never succeed. Callers may * be using allocators in order of preference for an area that is * too large. */ if (order >= MAX_ORDER) { WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN)); return NULL; } /* * 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 (IS_ENABLED(CONFIG_NUMA) && (gfp_mask & GFP_THISNODE) == GFP_THISNODE) goto nopage; restart: prepare_slowpath(gfp_mask, order, zonelist, high_zoneidx, preferred_zone); /* * 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. */ alloc_flags = gfp_to_alloc_flags(gfp_mask); /* * Find the true preferred zone if the allocation is unconstrained by * cpusets. */ if (!(alloc_flags & ALLOC_CPUSET) && !nodemask) first_zones_zonelist(zonelist, high_zoneidx, NULL, &preferred_zone); rebalance: /* This is the last chance, in general, before the goto nopage. */ page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist, high_zoneidx, alloc_flags & ~ALLOC_NO_WATERMARKS, preferred_zone, migratetype); if (page) goto got_pg; /* Allocate without watermarks if the context allows */ if (alloc_flags & ALLOC_NO_WATERMARKS) { /* * Ignore mempolicies if ALLOC_NO_WATERMARKS on the grounds * the allocation is high priority and these type of * allocations are system rather than user orientated */ zonelist = node_zonelist(numa_node_id(), gfp_mask); page = __alloc_pages_high_priority(gfp_mask, order, zonelist, high_zoneidx, nodemask, preferred_zone, migratetype); if (page) { goto got_pg; } } /* Atomic allocations - we can't balance anything */ if (!wait) goto nopage; /* Avoid recursion of direct reclaim */ if (current->flags & PF_MEMALLOC) goto nopage; /* Avoid allocations with no watermarks from looping endlessly */ if (test_thread_flag(TIF_MEMDIE) && !(gfp_mask & __GFP_NOFAIL)) goto nopage; /* * Try direct compaction. The first pass is asynchronous. Subsequent * attempts after direct reclaim are synchronous */ page = __alloc_pages_direct_compact(gfp_mask, order, zonelist, high_zoneidx, nodemask, alloc_flags, preferred_zone, migratetype, sync_migration, &contended_compaction, &deferred_compaction, &did_some_progress); if (page) goto got_pg; sync_migration = true; /* * If compaction is deferred for high-order allocations, it is because * sync compaction recently failed. In this is the case and the caller * requested a movable allocation that does not heavily disrupt the * system then fail the allocation instead of entering direct reclaim. */ if ((deferred_compaction || contended_compaction) && (gfp_mask & __GFP_NO_KSWAPD)) goto nopage; /* Try direct reclaim and then allocating */ page = __alloc_pages_direct_reclaim(gfp_mask, order, zonelist, high_zoneidx, nodemask, alloc_flags, preferred_zone, migratetype, &did_some_progress); if (page) goto got_pg; /* * If we failed to make any progress reclaiming, then we are * running out of options and have to consider going OOM */ if (!did_some_progress) { if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) { if (oom_killer_disabled) goto nopage; /* Coredumps can quickly deplete all memory reserves */ if ((current->flags & PF_DUMPCORE) && !(gfp_mask & __GFP_NOFAIL)) goto nopage; page = __alloc_pages_may_oom(gfp_mask, order, zonelist, high_zoneidx, nodemask, preferred_zone, migratetype); if (page) goto got_pg; if (!(gfp_mask & __GFP_NOFAIL)) { /* * The oom killer is not called for high-order * allocations that may fail, so if no progress * is being made, there are no other options and * retrying is unlikely to help. */ if (order > PAGE_ALLOC_COSTLY_ORDER) goto nopage; /* * The oom killer is not called for lowmem * allocations to prevent needlessly killing * innocent tasks. */ if (high_zoneidx < ZONE_NORMAL) goto nopage; } goto restart; } } /* Check if we should retry the allocation */ pages_reclaimed += did_some_progress; if (should_alloc_retry(gfp_mask, order, did_some_progress, pages_reclaimed)) { /* Wait for some write requests to complete then retry */ wait_iff_congested(preferred_zone, BLK_RW_ASYNC, HZ/50); goto rebalance; } else { /* * High-order allocations do not necessarily loop after * direct reclaim and reclaim/compaction depends on compaction * being called after reclaim so call directly if necessary */ page = __alloc_pages_direct_compact(gfp_mask, order, zonelist, high_zoneidx, nodemask, alloc_flags, preferred_zone, migratetype, sync_migration, &contended_compaction, &deferred_compaction, &did_some_progress); if (page) goto got_pg; } nopage: warn_alloc_failed(gfp_mask, order, NULL); return page; got_pg: if (kmemcheck_enabled) kmemcheck_pagealloc_alloc(page, order, gfp_mask); return page; } /* * This is the 'heart' of the zoned buddy allocator. */ struct page * __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, struct zonelist *zonelist, nodemask_t *nodemask) { enum zone_type high_zoneidx = gfp_zone(gfp_mask); struct zone *preferred_zone; struct page *page = NULL; int migratetype = allocflags_to_migratetype(gfp_mask); unsigned int cpuset_mems_cookie; int alloc_flags = ALLOC_WMARK_LOW|ALLOC_CPUSET; struct mem_cgroup *memcg = NULL; gfp_mask &= gfp_allowed_mask; lockdep_trace_alloc(gfp_mask); might_sleep_if(gfp_mask & __GFP_WAIT); if (should_fail_alloc_page(gfp_mask, order)) return NULL; /* * Check the zones suitable for the gfp_mask contain at least one * valid zone. It's possible to have an empty zonelist as a result * of GFP_THISNODE and a memoryless node */ if (unlikely(!zonelist->_zonerefs->zone)) return NULL; /* * Will only have any effect when __GFP_KMEMCG is set. This is * verified in the (always inline) callee */ if (!memcg_kmem_newpage_charge(gfp_mask, &memcg, order)) return NULL; retry_cpuset: cpuset_mems_cookie = get_mems_allowed(); /* The preferred zone is used for statistics later */ first_zones_zonelist(zonelist, high_zoneidx, nodemask ? : &cpuset_current_mems_allowed, &preferred_zone); if (!preferred_zone) goto out; #ifdef CONFIG_CMA if (allocflags_to_migratetype(gfp_mask) == MIGRATE_MOVABLE) alloc_flags |= ALLOC_CMA; #endif /* First allocation attempt */ page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order, zonelist, high_zoneidx, alloc_flags, preferred_zone, migratetype); if (unlikely(!page)) { /* * Runtime PM, block IO and its error handling path * can deadlock because I/O on the device might not * complete. */ gfp_mask = memalloc_noio_flags(gfp_mask); page = __alloc_pages_slowpath(gfp_mask, order, zonelist, high_zoneidx, nodemask, preferred_zone, migratetype); } trace_mm_page_alloc(page, order, gfp_mask, migratetype); out: /* * When updating a task's mems_allowed, it is possible to race with * parallel threads in such a way that an allocation can fail while * the mask is being updated. If a page allocation is about to fail, * check if the cpuset changed during allocation and if so, retry. */ if (unlikely(!put_mems_allowed(cpuset_mems_cookie) && !page)) goto retry_cpuset; memcg_kmem_commit_charge(page, memcg, order); return page; } EXPORT_SYMBOL(__alloc_pages_nodemask); /* * Common helper functions. */ unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order) { struct page *page; /* * __get_free_pages() returns a 32-bit address, which cannot represent * a highmem page */ VM_BUG_ON((gfp_mask & __GFP_HIGHMEM) != 0); 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) { return __get_free_pages(gfp_mask | __GFP_ZERO, 0); } EXPORT_SYMBOL(get_zeroed_page); void __free_pages(struct page *page, unsigned int order) { if (put_page_testzero(page)) { if (order == 0) free_hot_cold_page(page, 0); 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); /* * __free_memcg_kmem_pages and free_memcg_kmem_pages will free * pages allocated with __GFP_KMEMCG. * * Those pages are accounted to a particular memcg, embedded in the * corresponding page_cgroup. To avoid adding a hit in the allocator to search * for that information only to find out that it is NULL for users who have no * interest in that whatsoever, we provide these functions. * * The caller knows better which flags it relies on. */ void __free_memcg_kmem_pages(struct page *page, unsigned int order) { memcg_kmem_uncharge_pages(page, order); __free_pages(page, order); } void free_memcg_kmem_pages(unsigned long addr, unsigned int order) { if (addr != 0) { VM_BUG_ON(!virt_addr_valid((void *)addr)); __free_memcg_kmem_pages(virt_to_page((void *)addr), order); } } static void *make_alloc_exact(unsigned long addr, unsigned order, size_t size) { if (addr) { unsigned long alloc_end = addr + (PAGE_SIZE << order); unsigned long used = addr + PAGE_ALIGN(size); split_page(virt_to_page((void *)addr), order); while (used < alloc_end) { free_page(used); used += PAGE_SIZE; } } return (void *)addr; } /** * 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); return make_alloc_exact(addr, order, size); } EXPORT_SYMBOL(alloc_pages_exact); /** * alloc_pages_exact_nid - allocate an exact number of physically-contiguous * pages on a node. * @nid: the preferred node ID where memory should be allocated * @size: the number of bytes to allocate * @gfp_mask: GFP flags for the allocation * * Like alloc_pages_exact(), but try to allocate on node nid first before falling * back. * Note this is not alloc_pages_exact_node() which allocates on a specific node, * but is not exact. */ void *alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask) { unsigned order = get_order(size); struct page *p = alloc_pages_node(nid, gfp_mask, order); if (!p) return NULL; return make_alloc_exact((unsigned long)page_address(p), order, size); } EXPORT_SYMBOL(alloc_pages_exact_nid); /** * 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); /** * nr_free_zone_pages - count number of pages beyond high watermark * @offset: The zone index of the highest zone * * nr_free_zone_pages() counts the number of counts pages which are beyond the * high watermark within all zones at or below a given zone index. For each * zone, the number of pages is calculated as: * managed_pages - high_pages */ static unsigned long nr_free_zone_pages(int offset) { struct zoneref *z; struct zone *zone; /* Just pick one node, since fallback list is circular */ unsigned long sum = 0; struct zonelist *zonelist = node_zonelist(numa_node_id(), GFP_KERNEL); for_each_zone_zonelist(zone, z, zonelist, offset) { unsigned long size = zone->managed_pages; unsigned long high = high_wmark_pages(zone); if (size > high) sum += size - high; } return sum; } /** * nr_free_buffer_pages - count number of pages beyond high watermark * * nr_free_buffer_pages() counts the number of pages which are beyond the high * watermark within ZONE_DMA and ZONE_NORMAL. */ unsigned long nr_free_buffer_pages(void) { return nr_free_zone_pages(gfp_zone(GFP_USER)); } EXPORT_SYMBOL_GPL(nr_free_buffer_pages); /** * nr_free_pagecache_pages - count number of pages beyond high watermark * * nr_free_pagecache_pages() counts the number of pages which are beyond the * high watermark within all zones. */ unsigned long nr_free_pagecache_pages(void) { return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE)); } static inline void show_node(struct zone *zone) { if (IS_ENABLED(CONFIG_NUMA)) 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) { int zone_type; /* needs to be signed */ unsigned long managed_pages = 0; pg_data_t *pgdat = NODE_DATA(nid); for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) managed_pages += pgdat->node_zones[zone_type].managed_pages; val->totalram = managed_pages; val->freeram = node_page_state(nid, NR_FREE_PAGES); #ifdef CONFIG_HIGHMEM val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].managed_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 /* * Determine whether the node should be displayed or not, depending on whether * SHOW_MEM_FILTER_NODES was passed to show_free_areas(). */ bool skip_free_areas_node(unsigned int flags, int nid) { bool ret = false; unsigned int cpuset_mems_cookie; if (!(flags & SHOW_MEM_FILTER_NODES)) goto out; do { cpuset_mems_cookie = get_mems_allowed(); ret = !node_isset(nid, cpuset_current_mems_allowed); } while (!put_mems_allowed(cpuset_mems_cookie)); out: return ret; } #define K(x) ((x) << (PAGE_SHIFT-10)) static void show_migration_types(unsigned char type) { static const char types[MIGRATE_TYPES] = { [MIGRATE_UNMOVABLE] = 'U', [MIGRATE_RECLAIMABLE] = 'E', [MIGRATE_MOVABLE] = 'M', [MIGRATE_RESERVE] = 'R', #ifdef CONFIG_CMA [MIGRATE_CMA] = 'C', #endif #ifdef CONFIG_MEMORY_ISOLATION [MIGRATE_ISOLATE] = 'I', #endif }; char tmp[MIGRATE_TYPES + 1]; char *p = tmp; int i; for (i = 0; i < MIGRATE_TYPES; i++) { if (type & (1 << i)) *p++ = types[i]; } *p = '\0'; printk("(%s) ", tmp); } /* * 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. * Suppresses nodes that are not allowed by current's cpuset if * SHOW_MEM_FILTER_NODES is passed. */ void show_free_areas(unsigned int filter) { int cpu; struct zone *zone; for_each_populated_zone(zone) { if (skip_free_areas_node(filter, zone_to_nid(zone))) continue; show_node(zone); printk("%s per-cpu:\n", zone->name); for_each_online_cpu(cpu) { struct per_cpu_pageset *pageset; pageset = per_cpu_ptr(zone->pageset, 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 inactive_anon:%lu isolated_anon:%lu\n" " active_file:%lu inactive_file:%lu isolated_file:%lu\n" " unevictable:%lu" " dirty:%lu writeback:%lu unstable:%lu\n" " free:%lu slab_reclaimable:%lu slab_unreclaimable:%lu\n" " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n" " free_cma:%lu\n", global_page_state(NR_ACTIVE_ANON), global_page_state(NR_INACTIVE_ANON), global_page_state(NR_ISOLATED_ANON), global_page_state(NR_ACTIVE_FILE), global_page_state(NR_INACTIVE_FILE), global_page_state(NR_ISOLATED_FILE), global_page_state(NR_UNEVICTABLE), 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_SHMEM), global_page_state(NR_PAGETABLE), global_page_state(NR_BOUNCE), global_page_state(NR_FREE_CMA_PAGES)); for_each_populated_zone(zone) { int i; if (skip_free_areas_node(filter, zone_to_nid(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" " unevictable:%lukB" " isolated(anon):%lukB" " isolated(file):%lukB" " present:%lukB" " managed:%lukB" " mlocked:%lukB" " dirty:%lukB" " writeback:%lukB" " mapped:%lukB" " shmem:%lukB" " slab_reclaimable:%lukB" " slab_unreclaimable:%lukB" " kernel_stack:%lukB" " pagetables:%lukB" " unstable:%lukB" " bounce:%lukB" " free_cma:%lukB" " writeback_tmp:%lukB" " pages_scanned:%lu" " all_unreclaimable? %s" "\n", zone->name, K(zone_page_state(zone, NR_FREE_PAGES)), K(min_wmark_pages(zone)), K(low_wmark_pages(zone)), K(high_wmark_pages(zone)), 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)), K(zone_page_state(zone, NR_UNEVICTABLE)), K(zone_page_state(zone, NR_ISOLATED_ANON)), K(zone_page_state(zone, NR_ISOLATED_FILE)), K(zone->present_pages), K(zone->managed_pages), K(zone_page_state(zone, NR_MLOCK)), K(zone_page_state(zone, NR_FILE_DIRTY)), K(zone_page_state(zone, NR_WRITEBACK)), K(zone_page_state(zone, NR_FILE_MAPPED)), K(zone_page_state(zone, NR_SHMEM)), K(zone_page_state(zone, NR_SLAB_RECLAIMABLE)), K(zone_page_state(zone, NR_SLAB_UNRECLAIMABLE)), zone_page_state(zone, NR_KERNEL_STACK) * THREAD_SIZE / 1024, K(zone_page_state(zone, NR_PAGETABLE)), K(zone_page_state(zone, NR_UNSTABLE_NFS)), K(zone_page_state(zone, NR_BOUNCE)), K(zone_page_state(zone, NR_FREE_CMA_PAGES)), K(zone_page_state(zone, NR_WRITEBACK_TEMP)), zone->pages_scanned, (!zone_reclaimable(zone) ? "yes" : "no") ); printk("lowmem_reserve[]:"); for (i = 0; i < MAX_NR_ZONES; i++) printk(" %lu", zone->lowmem_reserve[i]); printk("\n"); } for_each_populated_zone(zone) { unsigned long nr[MAX_ORDER], flags, order, total = 0; unsigned char types[MAX_ORDER]; if (skip_free_areas_node(filter, zone_to_nid(zone))) continue; show_node(zone); printk("%s: ", zone->name); spin_lock_irqsave(&zone->lock, flags); for (order = 0; order < MAX_ORDER; order++) { struct free_area *area = &zone->free_area[order]; int type; nr[order] = area->nr_free; total += nr[order] << order; types[order] = 0; for (type = 0; type < MIGRATE_TYPES; type++) { if (!list_empty(&area->free_list[type])) types[order] |= 1 << type; } } spin_unlock_irqrestore(&zone->lock, flags); for (order = 0; order < MAX_ORDER; order++) { printk("%lu*%lukB ", nr[order], K(1UL) << order); if (nr[order]) show_migration_types(types[order]); } printk("= %lukB\n", K(total)); } hugetlb_show_meminfo(); 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) { struct zone *zone; enum zone_type zone_type = MAX_NR_ZONES; 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) { int ret; if (!s) return 0; ret = __parse_numa_zonelist_order(s); if (ret == 0) strlcpy(numa_zonelist_order, s, NUMA_ZONELIST_ORDER_LEN); return ret; } 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, void __user *buffer, size_t *length, loff_t *ppos) { char saved_string[NUMA_ZONELIST_ORDER_LEN]; int ret; static DEFINE_MUTEX(zl_order_mutex); mutex_lock(&zl_order_mutex); if (write) { if (strlen((char *)table->data) >= NUMA_ZONELIST_ORDER_LEN) { ret = -EINVAL; goto out; } strcpy(saved_string, (char *)table->data); } ret = proc_dostring(table, write, buffer, length, ppos); if (ret) goto out; if (write) { int oldval = user_zonelist_order; ret = __parse_numa_zonelist_order((char *)table->data); if (ret) { /* * 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) { mutex_lock(&zonelists_mutex); build_all_zonelists(NULL, NULL); mutex_unlock(&zonelists_mutex); } } out: mutex_unlock(&zl_order_mutex); return ret; } #define MAX_NODE_LOAD (nr_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 = NUMA_NO_NODE; const struct cpumask *tmp = cpumask_of_node(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_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 */ tmp = cpumask_of_node(n); if (!cpumask_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); 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); 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 system. * If they are really small and used heavily, the system can fall * into OOM very easily. * This function detect ZONE_DMA/DMA32 size and configures 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->managed_pages; total_size += z->managed_pages; } else if (zone_type == ZONE_NORMAL) { /* * If any node has only lowmem, then node order * is preferred to allow kernel allocations * locally; otherwise, they can easily infringe * on other nodes when there is an abundance of * lowmem available to allocate from. */ return ZONELIST_ORDER_NODE; } } } 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_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 = nr_online_nodes; prev_node = local_node; nodes_clear(used_mask); memset(node_order, 0, sizeof(node_order)); j = 0; while ((node = find_next_best_node(local_node, &used_mask)) >= 0) { /* * 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 (node_distance(local_node, node) != 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); } #ifdef CONFIG_HAVE_MEMORYLESS_NODES /* * Return node id of node used for "local" allocations. * I.e., first node id of first zone in arg node's generic zonelist. * Used for initializing percpu 'numa_mem', which is used primarily * for kernel allocations, so use GFP_KERNEL flags to locate zonelist. */ int local_memory_node(int node) { struct zone *zone; (void)first_zones_zonelist(node_zonelist(node, GFP_KERNEL), gfp_zone(GFP_KERNEL), NULL, &zone); return zone->node; } #endif #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); /* * 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); } for (node = 0; node < local_node; node++) { if (!node_online(node)) continue; j = build_zonelists_node(NODE_DATA(node), zonelist, j); } 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 */ /* * 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. * * 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 void setup_pageset(struct per_cpu_pageset *p, unsigned long batch); static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset); static void setup_zone_pageset(struct zone *zone); /* * Global mutex to protect against size modification of zonelists * as well as to serialize pageset setup for the new populated zone. */ DEFINE_MUTEX(zonelists_mutex); /* return values int ....just for stop_machine() */ static int __build_all_zonelists(void *data) { int nid; int cpu; pg_data_t *self = data; #ifdef CONFIG_NUMA memset(node_load, 0, sizeof(node_load)); #endif if (self && !node_online(self->node_id)) { build_zonelists(self); build_zonelist_cache(self); } for_each_online_node(nid) { pg_data_t *pgdat = NODE_DATA(nid); build_zonelists(pgdat); build_zonelist_cache(pgdat); } /* * Initialize the boot_pagesets that are going to be used * for bootstrapping processors. The real pagesets for * each zone will be allocated later when the per cpu * allocator is available. * * boot_pagesets are used also for bootstrapping offline * cpus if the system is already booted because the pagesets * are needed to initialize allocators on a specific cpu too. * F.e. the percpu allocator needs the page allocator which * needs the percpu allocator in order to allocate its pagesets * (a chicken-egg dilemma). */ for_each_possible_cpu(cpu) { setup_pageset(&per_cpu(boot_pageset, cpu), 0); #ifdef CONFIG_HAVE_MEMORYLESS_NODES /* * We now know the "local memory node" for each node-- * i.e., the node of the first zone in the generic zonelist. * Set up numa_mem percpu variable for on-line cpus. During * boot, only the boot cpu should be on-line; we'll init the * secondary cpus' numa_mem as they come on-line. During * node/memory hotplug, we'll fixup all on-line cpus. */ if (cpu_online(cpu)) set_cpu_numa_mem(cpu, local_memory_node(cpu_to_node(cpu))); #endif } return 0; } /* * Called with zonelists_mutex held always * unless system_state == SYSTEM_BOOTING. */ void __ref build_all_zonelists(pg_data_t *pgdat, struct zone *zone) { set_zonelist_order(); if (system_state == SYSTEM_BOOTING) { __build_all_zonelists(NULL); mminit_verify_zonelist(); cpuset_init_current_mems_allowed(); } else { #ifdef CONFIG_MEMORY_HOTPLUG if (zone) setup_zone_pageset(zone); #endif /* we have to stop all cpus to guarantee there is no user of zonelist */ stop_machine(__build_all_zonelists, pgdat, 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", nr_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)) /* * Check if a pageblock contains reserved pages */ static int pageblock_is_reserved(unsigned long start_pfn, unsigned long end_pfn) { unsigned long pfn; for (pfn = start_pfn; pfn < end_pfn; pfn++) { if (!pfn_valid_within(pfn) || PageReserved(pfn_to_page(pfn))) return 1; } return 0; } /* * Mark a number of pageblocks as MIGRATE_RESERVE. The number * of blocks reserved is based on min_wmark_pages(zone). 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, block_end_pfn; struct page *page; unsigned long block_migratetype; int reserve; /* * Get the start pfn, end pfn and the number of blocks to reserve * We have to be careful to be aligned to pageblock_nr_pages to * make sure that we always check pfn_valid for the first page in * the block. */ start_pfn = zone->zone_start_pfn; end_pfn = zone_end_pfn(zone); start_pfn = roundup(start_pfn, pageblock_nr_pages); reserve = roundup(min_wmark_pages(zone), pageblock_nr_pages) >> pageblock_order; /* * Reserve blocks are generally in place to help high-order atomic * allocations that are short-lived. A min_free_kbytes value that * would result in more than 2 reserve blocks for atomic allocations * is assumed to be in place to help anti-fragmentation for the * future allocation of hugepages at runtime. */ reserve = min(2, reserve); 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; block_migratetype = get_pageblock_migratetype(page); /* Only test what is necessary when the reserves are not met */ if (reserve > 0) { /* * Blocks with reserved pages will never free, skip * them. */ block_end_pfn = min(pfn + pageblock_nr_pages, end_pfn); if (pageblock_is_reserved(pfn, block_end_pfn)) continue; /* If this block is reserved, account for it */ if (block_migratetype == MIGRATE_RESERVE) { reserve--; continue; } /* Suitable for reserving if this block is movable */ if (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; if (highest_memmap_pfn < end_pfn - 1) highest_memmap_pfn = end_pfn - 1; 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); page_mapcount_reset(page); page_cpupid_reset_last(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 < zone_end_pfn(z)) && !(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 __meminit zone_batchsize(struct zone *zone) { #ifdef CONFIG_MMU 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->managed_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 = rounddown_pow_of_two(batch + batch/2) - 1; return batch; #else /* The deferral and batching of frees should be suppressed under NOMMU * conditions. * * The problem is that NOMMU needs to be able to allocate large chunks * of contiguous memory as there's no hardware page translation to * assemble apparent contiguous memory from discontiguous pages. * * Queueing large contiguous runs of pages for batching, however, * causes the pages to actually be freed in smaller chunks. As there * can be a significant delay between the individual batches being * recycled, this leads to the once large chunks of space being * fragmented and becoming unavailable for high-order allocations. */ return 0; #endif } /* * pcp->high and pcp->batch values are related and dependent on one another: * ->batch must never be higher then ->high. * The following function updates them in a safe manner without read side * locking. * * Any new users of pcp->batch and pcp->high should ensure they can cope with * those fields changing asynchronously (acording the the above rule). * * mutex_is_locked(&pcp_batch_high_lock) required when calling this function * outside of boot time (or some other assurance that no concurrent updaters * exist). */ static void pageset_update(struct per_cpu_pages *pcp, unsigned long high, unsigned long batch) { /* start with a fail safe value for batch */ pcp->batch = 1; smp_wmb(); /* Update high, then batch, in order */ pcp->high = high; smp_wmb(); pcp->batch = batch; } /* a companion to pageset_set_high() */ static void pageset_set_batch(struct per_cpu_pageset *p, unsigned long batch) { pageset_update(&p->pcp, 6 * batch, max(1UL, 1 * batch)); } static void pageset_init(struct per_cpu_pageset *p) { struct per_cpu_pages *pcp; int migratetype; memset(p, 0, sizeof(*p)); pcp = &p->pcp; pcp->count = 0; for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++) INIT_LIST_HEAD(&pcp->lists[migratetype]); } static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch) { pageset_init(p); pageset_set_batch(p, batch); } /* * pageset_set_high() sets the high water mark for hot per_cpu_pagelist * to the value high for the pageset p. */ static void pageset_set_high(struct per_cpu_pageset *p, unsigned long high) { unsigned long batch = max(1UL, high / 4); if ((high / 4) > (PAGE_SHIFT * 8)) batch = PAGE_SHIFT * 8; pageset_update(&p->pcp, high, batch); } static void __meminit pageset_set_high_and_batch(struct zone *zone, struct per_cpu_pageset *pcp) { if (percpu_pagelist_fraction) pageset_set_high(pcp, (zone->managed_pages / percpu_pagelist_fraction)); else pageset_set_batch(pcp, zone_batchsize(zone)); } static void __meminit zone_pageset_init(struct zone *zone, int cpu) { struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu); pageset_init(pcp); pageset_set_high_and_batch(zone, pcp); } static void __meminit setup_zone_pageset(struct zone *zone) { int cpu; zone->pageset = alloc_percpu(struct per_cpu_pageset); for_each_possible_cpu(cpu) zone_pageset_init(zone, cpu); } /* * Allocate per cpu pagesets and initialize them. * Before this call only boot pagesets were available. */ void __init setup_per_cpu_pageset(void) { struct zone *zone; for_each_populated_zone(zone) setup_zone_pageset(zone); } 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_nopanic(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) { /* * per cpu subsystem is not up at this point. The following code * relies on the ability of the linker to provide the * offset of a (static) per cpu variable into the per cpu area. */ zone->pageset = &boot_pageset; if (populated_zone(zone)) printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%u\n", zone->name, zone->present_pages, zone_batchsize(zone)); } int __meminit 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_HAVE_MEMBLOCK_NODE_MAP #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) { unsigned long start_pfn, end_pfn; int nid; /* * NOTE: The following SMP-unsafe globals are only used early in boot * when the kernel is running single-threaded. */ static unsigned long __meminitdata last_start_pfn, last_end_pfn; static int __meminitdata last_nid; if (last_start_pfn <= pfn && pfn < last_end_pfn) return last_nid; nid = memblock_search_pfn_nid(pfn, &start_pfn, &end_pfn); if (nid != -1) { last_start_pfn = start_pfn; last_end_pfn = end_pfn; last_nid = nid; } return nid; } #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 /** * 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) { unsigned long start_pfn, end_pfn; int i, this_nid; for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, &this_nid) { start_pfn = min(start_pfn, max_low_pfn); end_pfn = min(end_pfn, max_low_pfn); if (start_pfn < end_pfn) free_bootmem_node(NODE_DATA(this_nid), PFN_PHYS(start_pfn), (end_pfn - start_pfn) << PAGE_SHIFT); } } /** * 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) { unsigned long start_pfn, end_pfn; int i, this_nid; for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, &this_nid) memory_present(this_nid, start_pfn, end_pfn); } /** * 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) { unsigned long this_start_pfn, this_end_pfn; int i; *start_pfn = -1UL; *end_pfn = 0; for_each_mem_pfn_range(i, nid, &this_start_pfn, &this_end_pfn, NULL) { *start_pfn = min(*start_pfn, this_start_pfn); *end_pfn = max(*end_pfn, this_end_pfn); } if (*start_pfn == -1UL) *start_pfn = 0; } /* * 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 independent 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 node_start_pfn, unsigned long node_end_pfn, unsigned long *ignored) { unsigned long zone_start_pfn, zone_end_pfn; /* Get the start and end of the zone */ 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. */ unsigned long __meminit __absent_pages_in_range(int nid, unsigned long range_start_pfn, unsigned long range_end_pfn) { unsigned long nr_absent = range_end_pfn - range_start_pfn; unsigned long start_pfn, end_pfn; int i; for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) { start_pfn = clamp(start_pfn, range_start_pfn, range_end_pfn); end_pfn = clamp(end_pfn, range_start_pfn, range_end_pfn); nr_absent -= end_pfn - start_pfn; } return nr_absent; } /** * 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 node_start_pfn, unsigned long node_end_pfn, unsigned long *ignored) { unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type]; unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type]; unsigned long zone_start_pfn, zone_end_pfn; zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high); zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high); 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 /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ static inline unsigned long __meminit zone_spanned_pages_in_node(int nid, unsigned long zone_type, unsigned long node_start_pfn, unsigned long node_end_pfn, 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 node_start_pfn, unsigned long node_end_pfn, unsigned long *zholes_size) { if (!zholes_size) return 0; return zholes_size[zone_type]; } #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ static void __meminit calculate_node_totalpages(struct pglist_data *pgdat, unsigned long node_start_pfn, unsigned long node_end_pfn, 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, node_start_pfn, node_end_pfn, 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, node_start_pfn, node_end_pfn, 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 zone_start_pfn, unsigned long zonesize) { unsigned long usemapsize; zonesize += zone_start_pfn & (pageblock_nr_pages-1); 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 zone_start_pfn, unsigned long zonesize) { unsigned long usemapsize = usemap_size(zone_start_pfn, zonesize); zone->pageblock_flags = NULL; if (usemapsize) zone->pageblock_flags = alloc_bootmem_node_nopanic(pgdat, usemapsize); } #else static inline void setup_usemap(struct pglist_data *pgdat, struct zone *zone, unsigned long zone_start_pfn, unsigned long zonesize) {} #endif /* CONFIG_SPARSEMEM */ #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */ void __paginginit set_pageblock_order(void) { unsigned int order; /* Check that pageblock_nr_pages has not already been setup */ if (pageblock_order) return; if (HPAGE_SHIFT > PAGE_SHIFT) order = HUGETLB_PAGE_ORDER; else order = MAX_ORDER - 1; /* * Assume the largest contiguous order of interest is a huge page. * This value may be variable depending on boot parameters on IA64 and * powerpc. */ pageblock_order = order; } #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ /* * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order() * is 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 */ void __paginginit set_pageblock_order(void) { } #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ static unsigned long __paginginit calc_memmap_size(unsigned long spanned_pages, unsigned long present_pages) { unsigned long pages = spanned_pages; /* * Provide a more accurate estimation if there are holes within * the zone and SPARSEMEM is in use. If there are holes within the * zone, each populated memory region may cost us one or two extra * memmap pages due to alignment because memmap pages for each * populated regions may not naturally algined on page boundary. * So the (present_pages >> 4) heuristic is a tradeoff for that. */ if (spanned_pages > present_pages + (present_pages >> 4) && IS_ENABLED(CONFIG_SPARSEMEM)) pages = present_pages; return PAGE_ALIGN(pages * sizeof(struct page)) >> PAGE_SHIFT; } /* * Set up the zone data structures: * - mark all pages reserved * - mark all memory queues empty * - clear the memory bitmaps * * NOTE: pgdat should get zeroed by caller. */ static void __paginginit free_area_init_core(struct pglist_data *pgdat, unsigned long node_start_pfn, unsigned long node_end_pfn, 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); #ifdef CONFIG_NUMA_BALANCING spin_lock_init(&pgdat->numabalancing_migrate_lock); pgdat->numabalancing_migrate_nr_pages = 0; pgdat->numabalancing_migrate_next_window = jiffies; #endif init_waitqueue_head(&pgdat->kswapd_wait); init_waitqueue_head(&pgdat->pfmemalloc_wait); pgdat_page_cgroup_init(pgdat); for (j = 0; j < MAX_NR_ZONES; j++) { struct zone *zone = pgdat->node_zones + j; unsigned long size, realsize, freesize, memmap_pages; size = zone_spanned_pages_in_node(nid, j, node_start_pfn, node_end_pfn, zones_size); realsize = freesize = size - zone_absent_pages_in_node(nid, j, node_start_pfn, node_end_pfn, zholes_size); /* * Adjust freesize 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 = calc_memmap_size(size, realsize); if (freesize >= memmap_pages) { freesize -= memmap_pages; if (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 freesize %lu\n", zone_names[j], memmap_pages, freesize); /* Account for reserved pages */ if (j == 0 && freesize > dma_reserve) { freesize -= dma_reserve; printk(KERN_DEBUG " %s zone: %lu pages reserved\n", zone_names[0], dma_reserve); } if (!is_highmem_idx(j)) nr_kernel_pages += freesize; /* Charge for highmem memmap if there are enough kernel pages */ else if (nr_kernel_pages > memmap_pages * 2) nr_kernel_pages -= memmap_pages; nr_all_pages += freesize; zone->spanned_pages = size; zone->present_pages = realsize; /* * Set an approximate value for lowmem here, it will be adjusted * when the bootmem allocator frees pages into the buddy system. * And all highmem pages will be managed by the buddy system. */ zone->managed_pages = is_highmem_idx(j) ? realsize : freesize; #ifdef CONFIG_NUMA zone->node = nid; zone->min_unmapped_pages = (freesize*sysctl_min_unmapped_ratio) / 100; zone->min_slab_pages = (freesize * 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_pcp_init(zone); /* For bootup, initialized properly in watermark setup */ mod_zone_page_state(zone, NR_ALLOC_BATCH, zone->managed_pages); lruvec_init(&zone->lruvec); if (!size) continue; set_pageblock_order(); setup_usemap(pgdat, zone, zone_start_pfn, 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_end_pfn(pgdat); 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_nopanic(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_HAVE_MEMBLOCK_NODE_MAP if (page_to_pfn(mem_map) != pgdat->node_start_pfn) mem_map -= (pgdat->node_start_pfn - ARCH_PFN_OFFSET); #endif /* CONFIG_HAVE_MEMBLOCK_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); unsigned long start_pfn = 0; unsigned long end_pfn = 0; /* pg_data_t should be reset to zero when it's allocated */ WARN_ON(pgdat->nr_zones || pgdat->classzone_idx); pgdat->node_id = nid; pgdat->node_start_pfn = node_start_pfn; init_zone_allows_reclaim(nid); #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP get_pfn_range_for_nid(nid, &start_pfn, &end_pfn); #endif calculate_node_totalpages(pgdat, start_pfn, end_pfn, 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, start_pfn, end_pfn, zones_size, zholes_size); } #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP #if MAX_NUMNODES > 1 /* * Figure out the number of possible node ids. */ 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; } #endif /** * node_map_pfn_alignment - determine the maximum internode alignment * * This function should be called after node map is populated and sorted. * It calculates the maximum power of two alignment which can distinguish * all the nodes. * * For example, if all nodes are 1GiB and aligned to 1GiB, the return value * would indicate 1GiB alignment with (1 << (30 - PAGE_SHIFT)). If the * nodes are shifted by 256MiB, 256MiB. Note that if only the last node is * shifted, 1GiB is enough and this function will indicate so. * * This is used to test whether pfn -> nid mapping of the chosen memory * model has fine enough granularity to avoid incorrect mapping for the * populated node map. * * Returns the determined alignment in pfn's. 0 if there is no alignment * requirement (single node). */ unsigned long __init node_map_pfn_alignment(void) { unsigned long accl_mask = 0, last_end = 0; unsigned long start, end, mask; int last_nid = -1; int i, nid; for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, &nid) { if (!start || last_nid < 0 || last_nid == nid) { last_nid = nid; last_end = end; continue; } /* * Start with a mask granular enough to pin-point to the * start pfn and tick off bits one-by-one until it becomes * too coarse to separate the current node from the last. */ mask = ~((1 << __ffs(start)) - 1); while (mask && last_end <= (start & (mask << 1))) mask <<= 1; /* accumulate all internode masks */ accl_mask |= mask; } /* convert mask to number of pages */ return ~accl_mask + 1; } /* Find the lowest pfn for a node */ static unsigned long __init find_min_pfn_for_node(int nid) { unsigned long min_pfn = ULONG_MAX; unsigned long start_pfn; int i; for_each_mem_pfn_range(i, nid, &start_pfn, NULL, NULL) min_pfn = min(min_pfn, 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_MEMORY for calculating usable_nodes. */ static unsigned long __init early_calculate_totalpages(void) { unsigned long totalpages = 0; unsigned long start_pfn, end_pfn; int i, nid; for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) { unsigned long pages = end_pfn - start_pfn; totalpages += pages; if (pages) node_set_state(nid, N_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(void) { int i, nid; unsigned long usable_startpfn; unsigned long kernelcore_node, kernelcore_remaining; /* save the state before borrow the nodemask */ nodemask_t saved_node_state = node_states[N_MEMORY]; unsigned long totalpages = early_calculate_totalpages(); int usable_nodes = nodes_weight(node_states[N_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) goto out; /* 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_MEMORY) { unsigned long start_pfn, end_pfn; /* * 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_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) { unsigned long size_pages; start_pfn = max(start_pfn, zone_movable_pfn[nid]); 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 * satisfied */ 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 * satisfied */ 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); out: /* restore the node_state */ node_states[N_MEMORY] = saved_node_state; } /* Any regular or high memory on that node ? */ static void check_for_memory(pg_data_t *pgdat, int nid) { enum zone_type zone_type; if (N_MEMORY == N_NORMAL_MEMORY) return; for (zone_type = 0; zone_type <= ZONE_MOVABLE - 1; zone_type++) { struct zone *zone = &pgdat->node_zones[zone_type]; if (populated_zone(zone)) { node_set_state(nid, N_HIGH_MEMORY); if (N_NORMAL_MEMORY != N_HIGH_MEMORY && zone_type <= ZONE_NORMAL) node_set_state(nid, N_NORMAL_MEMORY); break; } } } /** * 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 start_pfn, end_pfn; int i, nid; /* 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(); /* Print out the zone ranges */ printk("Zone ranges:\n"); for (i = 0; i < MAX_NR_ZONES; i++) { if (i == ZONE_MOVABLE) continue; printk(KERN_CONT " %-8s ", zone_names[i]); if (arch_zone_lowest_possible_pfn[i] == arch_zone_highest_possible_pfn[i]) printk(KERN_CONT "empty\n"); else printk(KERN_CONT "[mem %0#10lx-%0#10lx]\n", arch_zone_lowest_possible_pfn[i] << PAGE_SHIFT, (arch_zone_highest_possible_pfn[i] << PAGE_SHIFT) - 1); } /* Print out the PFNs ZONE_MOVABLE begins at in each node */ printk("Movable zone start for each node\n"); for (i = 0; i < MAX_NUMNODES; i++) { if (zone_movable_pfn[i]) printk(" Node %d: %#010lx\n", i, zone_movable_pfn[i] << PAGE_SHIFT); } /* Print out the early node map */ printk("Early memory node ranges\n"); for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) printk(" node %3d: [mem %#010lx-%#010lx]\n", nid, start_pfn << PAGE_SHIFT, (end_pfn << PAGE_SHIFT) - 1); /* 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_MEMORY); check_for_memory(pgdat, nid); } } 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_HAVE_MEMBLOCK_NODE_MAP */ void adjust_managed_page_count(struct page *page, long count) { spin_lock(&managed_page_count_lock); page_zone(page)->managed_pages += count; totalram_pages += count; #ifdef CONFIG_HIGHMEM if (PageHighMem(page)) totalhigh_pages += count; #endif spin_unlock(&managed_page_count_lock); } EXPORT_SYMBOL(adjust_managed_page_count); unsigned long free_reserved_area(void *start, void *end, int poison, char *s) { void *pos; unsigned long pages = 0; start = (void *)PAGE_ALIGN((unsigned long)start); end = (void *)((unsigned long)end & PAGE_MASK); for (pos = start; pos < end; pos += PAGE_SIZE, pages++) { if ((unsigned int)poison <= 0xFF) memset(pos, poison, PAGE_SIZE); free_reserved_page(virt_to_page(pos)); } if (pages && s) pr_info("Freeing %s memory: %ldK (%p - %p)\n", s, pages << (PAGE_SHIFT - 10), start, end); return pages; } EXPORT_SYMBOL(free_reserved_area); #ifdef CONFIG_HIGHMEM void free_highmem_page(struct page *page) { __free_reserved_page(page); totalram_pages++; page_zone(page)->managed_pages++; totalhigh_pages++; } #endif void __init mem_init_print_info(const char *str) { unsigned long physpages, codesize, datasize, rosize, bss_size; unsigned long init_code_size, init_data_size; physpages = get_num_physpages(); codesize = _etext - _stext; datasize = _edata - _sdata;


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